0001447028-24-000035 | 10-K | XBRL Viewer

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Fair value measurements - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair value of contingent consideration	$ 7,600	$ 7,531	$ 5,298
Increase in fair value of contingent consideration	$ 69	$ 2,233

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Revenue
Revenues	$ 18,141	$ 39,019
Operating expenses
Research and development	73,700	84,408
General and administrative	22,475	17,834
Change in fair value of contingent consideration	69	2,233
Total operating expenses	96,244	104,475
Loss from operations	(78,103)	(65,456)
Other income
Interest income	5,688	2,192
Interest expense	(459)	(1,726)
Foreign exchange (loss) gain	25	(22)
Total other income	5,254	444
Loss before income taxes	(72,849)	(65,012)
Income tax expense	0	4,444
Net loss	$ (72,849)	$ (69,456)
Loss per share
Basic (in USD per share)	$ (0.44)	$ (0.46)
Diluted (in USD per share)	$ (0.44)	$ (0.46)
Weighted average number of common shares
Basic (in shares)	165,960,379	150,939,337
Diluted (in shares)	165,960,379	150,939,337
Comprehensive loss
Unrealized gain/(loss) on available-for-sale securities	$ 2,067	$ (2,153)
Comprehensive loss	$ (70,782)	(71,609)
Stock Option
Comprehensive loss
Number of additional shares authorized (in shares)	7,672,299
Collaborations and licenses
Revenue
Revenues	$ 14,274	31,366
Non-cash royalty revenue
Revenue
Revenues	$ 3,867	$ 7,653

Property and equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property and equipment

The Company’s property and equipment balances as of the years ended December 31, 2023 and 2022 are as follows:


	Cost		Accumulated depreciation		Net book value
December 31, 2023	(in thousands)
Lab equipment	$	7,593	$	(5,892)	$	1,701
Leasehold improvements	8,590		(5,618)		2,972
Computer hardware and software	391		(390)		1
	$	16,574	$	(11,900)	$	4,674


	Cost		Accumulated depreciation		Net book value
December 31, 2022	(in thousands)
Lab equipment	$	6,890	$	(5,679)	$	1,211
Leasehold improvements	8,590		(4,749)		3,841
Computer hardware and software	391		(373)		18
	$	15,871	$	(10,801)	$	5,070

Depreciation expense for the years ended December 31, 2023 and 2022 was $1.4 million for both years.

Collaborations and royalty entitlements (Tables)

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Schedule of revenue recognized under collaborations, contracts and licensing agreements

Revenues from the Company’s royalty entitlements are summarized in the following table:


	Year ended December 31,
	2023		2022
	(in thousands)
Revenue from collaborations and licenses
Royalties from sales of Onpattro	$	3,608	$	5,316
Qilu Pharmaceutical Co., Ltd.	10,666		26,015
Other milestone and royalty payments	—		35
Non-cash royalty revenue
Royalties from sales of Onpattro	3,867		7,653
Total revenue	$	18,141	$	39,019

Stock-based compensation - Stock option activity for liability-classified options (Details) - Liability classified stock options	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Number of optioned common shares
Balance - Number of optioned common shares (in shares) \| shares	20,000
Weighted average exercise price
Balance - Weighted average exercise price (in CAD and USD per share) \| $ / shares	$ 12.10

Leases - Lease cost (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease cost (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Weighted-average remaining lease term (years)	3 years 3 months 18 days
Weighted average discount rate	9.00%
Cash paid for amounts included in the measurement of lease liabilities	$ 598	$ 641

Contingencies and commitments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 31, 2014
Contingencies and Commitments [Line Items]
Contingent consideration	$ 7,600	$ 7,531	$ 5,298
Fair Value, Measurements, Recurring
Contingencies and Commitments [Line Items]
Contingent consideration	7,600	$ 7,531
Fair Value, Measurements, Recurring \| Enantigen's Selling Shareholders
Contingencies and Commitments [Line Items]
Contingent consideration	7,600
Blumberg and Drexel \| Fair Value, Measurements, Recurring \| Enantigen
Contingencies and Commitments [Line Items]
Contingent consideration	$ 0
Blumberg and Drexel \| Arbutus Inc.
Contingencies and Commitments [Line Items]
Development and regulatory milestones payment per licensed compound series, maximum				$ 102,500
Maximum royalty payment				$ 1,000

Stock-based compensation - Activity related to stock options (Details) - $ / shares	1 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2023
Arbutus Plans \| Employee Stock Option [Member]
Number of optioned common shares
Balance - Number of optioned common shares (in shares)		15,349,998
Options granted (in shares)		5,082,640
Options exercised (in shares)		(101,356)
Options forfeited, canceled or expired (in shares)		(1,267,117)
Options vested (in shares)		0
Balance - Number of optioned common shares (in shares)		19,064,165
Weighted average exercise price
Balance - Weighted average exercise price (in CAD and USD per share)		$ 3.76
Options granted - Weighted average exercise price (in CAD and USD per share)		2.78
Options exercised - Weighted average exercise price (in CAD and USD per share)		2.56
Options forfeited, canceled or expired - Weighted average exercise price (in CAD and USD per share)		4.39
Options vested (USD per share)		0
Balance - Weighted average exercise price (in CAD and USD per share)		$ 3.47
Arbutus Plans \| Vested [Member]
Number of optioned common shares
Balance - Number of optioned common shares (in shares)		9,631,779
Options granted (in shares)		0
Options exercised (in shares)		(101,356)
Options forfeited, canceled or expired (in shares)		(698,937)
Options vested (in shares)		3,500,403
Balance - Number of optioned common shares (in shares)		12,331,889
Arbutus Plans \| Non-Vested Stock Options
Number of optioned common shares
Balance - Number of optioned common shares (in shares)		5,718,219
Options granted (in shares)		5,082,640
Options exercised (in shares)		0
Options forfeited, canceled or expired (in shares)		(568,180)
Options vested (in shares)		3,500,403
Balance - Number of optioned common shares (in shares)		6,732,276
Weighted average exercise price
Balance - Weighted average exercise price (in CAD and USD per share)		$ 2.39
Options granted - Weighted average exercise price (in CAD and USD per share)		2.15
Options exercised - Weighted average exercise price (in CAD and USD per share)		0
Options forfeited, canceled or expired - Weighted average exercise price (in CAD and USD per share)		2.24
Options vested (USD per share)		2.33
Balance - Weighted average exercise price (in CAD and USD per share)		$ 2.25
Collier Plan
Number of optioned common shares
Options granted (in shares)	1,112,000

Significant accounting policies - Estimated useful lives of property and equipment (Details)	Dec. 31, 2023
Laboratory equipment
Property, Plant and Equipment [Line Items]
Useful lives	5 years
Computer and office equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful lives	2 years
Computer and office equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful lives	5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful lives	5 years

Stock-based compensation - Restricted Stock Units (Details)	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Number
Balance at end of period (in shares)	1,231,450
Restricted Stock Units (RSUs)
Number
Balance at beginning of period (in shares)	0
Balance at end of period (in shares)	1,231,450
Number
Balance at beginning of period (in shares)	0
Balance at end of period (in shares)	1,231,450
Arbutus Plans \| Restricted Stock Units (RSUs)
Number
Restricted stock units granted (in shares)	1,344,550
Restricted stock units forfeited, canceled or expired (in shares)	(113,100)
Weighted-Average Grant-Date Fair Value
Balance at beginning of period (in dollars per share) \| $ / shares	$ 0
Restricted stock units granted (in dollars per share) \| $ / shares	2.90
Restricted stock units forfeited, canceled or expired (in dollars per share) \| $ / shares	2.90
Balance at end of period (in dollars per share) \| $ / shares	$ 2.90
Number
Restricted stock units granted (in shares)	1,344,550
Restricted stock units vested (in shares)	0
Restricted stock units forfeited, canceled or expired (in shares)	113,100

Stock-based compensation - Valuation assumptions for stock options under the Arbutus Plan (Details) - Arbutus Plans	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected average option term	5 years 7 months 6 days	5 years 6 months
Expected volatility	97.10%	97.00%
Expected dividends	0.00%	0.00%
Risk-free interest rate	3.57%	1.77%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Shareholders’ equity (Details) - USD ($) $ in Thousands	12 Months Ended
Shareholders’ equity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Oct. 22, 2023	Mar. 03, 2022	Nov. 04, 2021	Oct. 08, 2021	Mar. 04, 2021	Oct. 22, 2020	Aug. 07, 2020	Jan. 10, 2020
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	1,164,000
Stock Option
Class of Stock [Line Items]
Number of additional shares authorized (in shares)	7,672,299
Common Shares \| Jan 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price										$ 150,000
Common Shares \| Oct 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price								$ 200,000
Common Shares \| Nov 2021 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price					$ 250,000
Jefferies LLC \| Common Shares \| October 2021 Prospectus Supplement \| Oct 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price						$ 75,000
Common Stock, Value, Subscriptions Expired			$ 29,300
Jefferies LLC \| Common Shares \| Sale Agreement
Class of Stock [Line Items]
Number of shares issued under agreement	12,020,257	8,645,426
Proceeds from issuance of common stock	$ 29,900	$ 20,300
Jefferies LLC \| Common Shares \| Aug 2020 Prospectus Supplement \| Jan 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price									$ 75,000
Jefferies LLC \| Common Shares \| Mar 2021 Prospectus Supplement Agreement \| Oct 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price							$ 75,000
Jefferies LLC \| Common Shares \| March 2022 Prospectus Supplement
Class of Stock [Line Items]
Aggregate share sales price	70,900
Jefferies LLC \| Common Shares \| March 2022 Prospectus Supplement \| Jan 2020 Oct 2020 and Nov 2021 Registration Stmts
Class of Stock [Line Items]
Aggregate share sales price				$ 100,000
Jefferies LLC \| Common Shares \| Jan 2020 Prospectus Supplement \| Jan 2020 Registration Stmt
Class of Stock [Line Items]
Aggregate share sales price										$ 50,000
Qilu Pharmaceutical Co, LTD.
Class of Stock [Line Items]
Income Taxes Paid	$ 4,400	$ 4,400

Accounts payable and accrued liabilities

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Accounts payable and accrued liabilities

Accounts payable and accrued liabilities are comprised of the following:


	December 31, 2023		December 31, 2022
	(in thousands)
Trade accounts payable	$	3,223	$	3,520
Payroll accruals	3,349		3,730
Research and development accruals	2,884		8,261
Professional fee accruals	815		512
Other accrued liabilities	—		6
Total	$	10,271	$	16,029

In connection with the Company’s decision in September 2023 to focus its pipeline on its HBV clinical stage compounds and discontinue certain research programs, the Company took steps to streamline the organization and reduced its workforce by 24% in November 2023, primarily affecting the research function. As a result, the Company incurred a one-time restructuring charge of approximately $1.1 million in the fourth quarter 2023, of which $0.2 million was accrued and included in payroll accruals as of December 31, 2023.

Leases - Narrative (Details) $ in Millions	12 Months Ended
Leases - Narrative (Details) $ in Millions	Dec. 31, 2023 USD ($) lease renewal_option	Dec. 31, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Number of operating leases \| lease	1
Renewal term	5 years
Fixed lease payment	$ 0.5	$ 0.6
Variable lease payment	0.1	0.1
Operating Lease, Cost	$ 0.6	$ 0.7
Corporate Headquarters Located 701 Veterans Circle, Warminster, Pennsylvania
Lessee, Lease, Description [Line Items]
Number of renewal options \| renewal_option	2
Discount rate	9.00%
Offices Located at 626 Jacksonville Rd., Warminster, Pennsylvania
Lessee, Lease, Description [Line Items]
Discount rate	7.60%

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net loss	$ (72,849)	$ (69,456)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Organization	12 Months Ended
Organization	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Description of the Business Arbutus Biopharma Corporation (“Arbutus” or the “Company”) is a clinical-stage biopharmaceutical company leveraging its extensive virology expertise to identify and develop novel therapeutics with distinct mechanisms of action, which can potentially be combined to provide a functional cure for patients with chronic hepatitis B virus (cHBV) infection. The Company believes the key to success in developing a functional cure involves suppressing HBV DNA, reducing surface antigen and boosting HBV-specific immune responses. The Company’s pipeline of internally developed, proprietary compounds includes an RNAi therapeutic, imdusiran (AB-729), and an oral PD-L1 inhibitor, AB-101. Imdusiran has generated meaningful clinical data demonstrating an impact on both surface antigen reduction and reawakening of the HBV-specific immune response. Imdusiran is currently in two Phase 2a combination clinical trials. AB-101 is currently being evaluated in a Phase 1a/1b clinical trial. Liquidity At December 31, 2023, the Company had an aggregate of $132.3 million in cash, cash equivalents and investments in marketable securities. The Company had no outstanding debt as of December 31, 2023. The Company believes it has sufficient cash, cash equivalents and investments in marketable securities to fund its operations for at least the next 12 months. The success of the Company is dependent on obtaining the necessary regulatory approvals to bring its products to market and achieve profitable operations. The Company’s research and development activities and the commercialization of its products are dependent on its ability to successfully complete these activities and to obtain adequate financing through a combination of financing activities and operations. It is not possible to predict either the outcome of the Company’s existing or future research and development programs or the Company’s ability to continue to fund these programs in the future.

Collaborations and royalty entitlements - Narrative (Details)					12 Months Ended		42 Months Ended
	Jan. 06, 2022 USD ($)	Jan. 05, 2022 USD ($)	Jul. 02, 2019 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2023 USD ($) product shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2022 USD ($) shares	Dec. 13, 2021 USD ($) $ / shares shares	Apr. 11, 2018
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Common shares, shares issued (in shares) \| shares					169,867,414	157,455,363	157,455,363
Number of royalty entitlements \| product					2
Non-cash royalty revenue					$ 3,867,000	$ 7,653,000
Total revenue					18,141,000	39,019,000
Total deferred revenue					11,791,000
License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Equity method investment, percentage or revenue entitled									50.00%
Non-cash royalty revenue
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue					3,867,000	7,653,000
Common Shares \| Qilu
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners								2.50%
Qilu
Research and Development Arrangement, Contract to Perform for Others [Line Items]
License Agreement Milestone payment maximum								$ 245,000,000
Qilu \| Common Shares
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Common shares, shares issued (in shares) \| shares								3,579,952
Shares price (in USD per share) \| $ / shares								$ 4.19
Premium percentage on closing stock price								15.00%
Issuance of common shares pursuant to Share Purchase Agreement	$ 15,000,000
Qilu \| One-Time Upfront Cash Payment
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Cash payment for collaborations		$ 40,000,000
Assembly
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Costs related to collaboration					1,300,000	2,800,000
Barinthus
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Costs related to collaboration					$ 1,800,000	800,000
Percent of Costs related to Collaboration					50.00%
OMERS
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty interest sold, percentage of sales, annual revenue threshold of highest tier			$ 500,000,000
Gross proceeds from royalty interest sold				$ 20,000,000
Royalty interest sold, maximum royalties for buyer			$ 30,000,000
Royalty guarantees commitments percentage			100.00%
Royalty payable			$ 30,000,000
Non-cash royalty revenue					$ 3,900,000	7,700,000	$ (22,700,000)
OMERS \| Minimum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty, percentage of interest sold			1.00%
OMERS \| Maximum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty, percentage of interest sold			2.33%
Onpattro - Cash Royalty [Member] \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue					3,608,000	5,316,000
Qilu Pharmaceutical Co, LTD.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total deferred revenue					11,800,000
Revenue, Remaining Performance Obligation, Amount					13,764,000			$ 50,445,000
Qilu Pharmaceutical Co, LTD. \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue					10,666,000	26,015,000
Qilu Pharmaceutical Co, LTD. \| One-Time Upfront Cash Payment
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Cash payment for collaborations					40,000,000
Other Milestones and Royalty Payments [Member] \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue					0	35,000
Onpattro - Non-cash Royalty [Member] \| Non-cash royalty revenue
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue					$ 3,867,000	$ 7,653,000

Income taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of effective income tax rate reconciliation

Income tax expense varies from the amounts that would be computed by applying the combined Canadian federal and provincial income tax rate of 27% (2022 - 27%) to the loss before income taxes as shown in the following tables:


	Year ended December 31,
	2023		2022
	(in thousands)
Computed taxes (benefits) at Canadian federal and provincial tax rates	$	(19,668)	$	(17,554)
Withholding taxes	—		4,444
Other	(2,108)		761
Permanent and other differences	198		869
Federal R&D credit	(1,741)		—
Foreign tax credit applied	—		(4,444)
Federal and Provincial ITCs applied	(179)		(324)
Change in valuation allowance	18,425		14,563
Difference due to income taxed at foreign rates	5,260		5,625
Stock-based compensation	(187)		504
Income tax expense	$	—	$	4,444

Schedule of components of deferred tax assets

Significant components of the Company’s deferred tax assets and liabilities are shown below:


	As of December 31,
	2023		2022
	(in thousands)
Deferred tax assets (liabilities):
Operating loss carryforwards	$	89,090	$	83,564
Canadian research and development deductions	16,726		16,791
Book amortization in excess of tax	(451)		(461)
Revenue recognized for tax purposes in excess of revenue recognized for accounting purposes	1,878		2,799
Tax value in excess of accounting value in lease inducements	74		93
Deferred revenue	3,184		6,063
Canadian Federal investment tax credits	5,147		5,278
Canadian Provincial investment tax credits	1,953		1,953
Equity method investment	3,375		3,375
U.S. Federal research and development credits	7,254		3,633
Deductible stock options	6,058		3,681
U.S. research and experimental expenditures capitalization	27,265		16,471
Accrued interest payable	1,722		1,507
Amortization	322		387
Other	114		153
Total deferred tax assets	$	163,711	$	145,287
Valuation allowance	(163,711)		(145,287)
Net deferred tax assets (liabilities)	$	—	$	—

Significant accounting policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Significant accounting policies

Basis of presentation and principles of consolidation

These consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and include the accounts of Arbutus Biopharma Corporation and its one wholly-owned subsidiary, Arbutus Biopharma, Inc. All intercompany balances and transactions have been eliminated. Certain prior year amounts have been reclassified to conform to the current year presentation.

Use of estimates

The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions about future events that affect the reported amounts of assets, liabilities, revenue, expenses and contingent liabilities as of the end or during the reporting period. Actual results could significantly differ from those estimates. Significant estimates in the accompanying consolidated financial statements impact contingent consideration, stock-based compensation, clinical trial accruals and the sale of future royalties liability.

Cash and cash equivalents

Cash and cash equivalents are all highly liquid instruments with an original maturity of three months or less when purchased. Cash equivalents are recorded at cost plus accrued interest. The carrying value of these cash equivalents approximates their fair value.

Investments in marketable securities

The Company’s short-term investments consist of marketable securities that have original maturities exceeding three months and remaining maturities of less than one year. The Company classifies investments with remaining maturities of one year or longer as non-current. These investments are accounted for as available-for-sale securities and are reported at fair value, with unrealized gains and losses reported in other comprehensive loss until their disposition. Realized gains and losses from the sale of marketable securities, if any, are calculated using the specific-identification method, and are recorded as a component of other income or loss. The Company reviews its available-for-sale securities at each period end to determine if they remain available-for-sale based on the Company’s current intent and ability to sell the security if it is required to do so. Declines in value judged to be other-than-temporary are included in interest expense in the Company’s statements of operations and comprehensive loss. As of December 31, 2023, the recorded value of the Company’s investments in marketable securities was deemed to be recoverable in all respects.

All investments are governed by the Company’s Investment Policy approved by the Company’s board of directors.

Foreign currency translation and functional currency conversion

The Company’s functional currency is the United States dollar. Monetary assets and liabilities denominated in foreign currencies are translated into United States dollars using exchange rates in effect at the balance sheet date. Opening balances related to non-monetary assets and liabilities are based on prior period translated amounts, and non-monetary assets and non-monetary liabilities are translated at the approximate exchange rate prevailing at the date of the transaction. Revenue and expense transactions are translated at the approximate exchange rate in effect at the time of the transaction. Foreign exchange gains and losses are included in the statement of operations and comprehensive loss as foreign exchange gains or losses.

Investment in Genevant

Arbutus accounts for its interest in Genevant as equity securities without readily determinable fair values. Accordingly, an estimate of the fair value of the securities is based on the original cost less previously recognized equity method losses, less impairments, plus or minus changes resulting from observable price changes in orderly transactions for identical or similar Genevant securities. As of December 31, 2023, Arbutus owned approximately 16% of the common equity of Genevant and the carrying value of Arbutus’ investment in Genevant was zero.

See note 5 for more information.

Property and equipment

Property and equipment is recorded at cost less impairment losses and accumulated depreciation. The Company records depreciation using the straight-line method over the estimated useful lives of the capital assets as follows:


	Useful Life (Years)
Laboratory equipment		5
Computer and office equipment	2	to	5
Furniture and fixtures		5

Leasehold improvements are depreciated over their estimated useful lives but in no case longer than the lease term, except where lease renewal is reasonably assured.

Property and equipment is reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. If such a review should indicate that the carrying amount of long-lived assets is not recoverable, then such assets are written down to their fair values.

Revenue from collaborations and licenses

The Company generates revenue primarily through collaboration agreements and license agreements. Such agreements may require the Company to deliver various rights and/or services, including intellectual property rights or licenses and research, development and manufacturing services. Under such agreements, the Company is generally eligible to receive non-refundable upfront payments, funding for research, development and manufacturing services, milestone payments, and royalties.

The Company’s collaboration agreements fall under the scope of Accounting Standards Codification (ASC) Topic 808, Collaborative Arrangements (ASC 808), when both parties are active participants in the arrangement and are exposed to significant risks and rewards. For certain arrangements under the scope of ASC 808, the Company analogizes to ASC Topic 606, Revenue from Contracts with Customers (ASC 606), for some aspects, including for the delivery of a good or service (i.e., a unit of account).

ASC 606 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers under a five-step model: (i) identify contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as a performance obligation is satisfied.

In contracts where the Company has more than one performance obligation to provide its customer with goods or services, each performance obligation is evaluated to determine whether it is distinct based on whether: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available; and (ii) the good or service is separately identifiable from other promises in the contract. The consideration under the contract is then allocated between the distinct performance obligations based on their respective relative stand-alone selling prices. The estimated stand-alone selling price of each deliverable reflects the Company’s best estimate of what the selling price would be if the deliverable was regularly sold on a stand-alone basis and is determined by reference to market rates for the good or service when sold to others or by using an adjusted market assessment approach if the selling price on a stand-alone basis is not available.

The consideration allocated to each distinct performance obligation is recognized as revenue when control is transferred to the customer for the related goods or services. Consideration associated with at-risk substantive performance milestones, including sales-based milestones, is recognized as revenue when it is probable that a significant reversal of the cumulative revenue recognized will not occur. Sales-based royalties received in connection with licenses of intellectual property are subject to a specific exception in the revenue standards, whereby the consideration is not included in the transaction price and recognized in revenue until the customer’s subsequent sales or usages occur.

Leases

The Company accounts for its lease under ASC 842, Leases, which generally requires the recognition of operating and financing lease liabilities with corresponding right-of-use assets on the balance sheet. See note 6 for more information.

Research and development costs

Research and development costs include compensation and benefits for research and development employees, an allocation of overhead expenses and costs associated with materials and supplies used in clinical trials and research and development, outside contracted services including clinical and preclinical study costs, legal, regulatory compliance and fees paid to consultants or outside parties for research and development activities performed on the Company’s behalf. Such costs are charged to expense in the period in which they are incurred.

Research and development costs that are paid in advance of performance or receipt are recorded as prepaid expense and are amortized over the period that the services are performed.

Net loss per share

Net loss per share is calculated based on the weighted average number of common shares outstanding. Diluted net loss per share does not differ from basic net loss per share for the years ended December 31, 2023 and 2022, since the effect of including potential common shares would be anti-dilutive. For the year ended December 31, 2023, potential common shares of 20.4 million pertaining to outstanding stock options and unvested restricted stock units were excluded from the calculation of net loss per share. A total of approximately 15.5 million outstanding stock options were excluded from the calculation for the year ended December 31, 2022.

See note 12 and note 13 for more information about the Company’s common shares.

Deferred income taxes

Income taxes are accounted for using the asset and liability method of accounting. Deferred income taxes are recognized for the future income tax consequences attributable to differences between the carrying values of assets and liabilities and their respective income tax bases and for loss carry-forwards. Deferred income tax assets and liabilities are measured using enacted income tax rates expected to apply to taxable income in the periods in which temporary differences are expected to be recovered or settled. The effect on deferred income tax assets and liabilities of a change in tax laws or rates is included in earnings in the period that includes the enactment date. When realization of deferred income tax assets does not meet the more-likely-than-not criterion for recognition, a valuation allowance is provided.

Stock-based compensation

The Company measures and recognizes compensation expense for all share-based compensation arrangements based on estimated fair values. The Company uses the Black-Scholes option valuation model to estimate the fair value of stock options at the date of grant. The Black-Scholes option valuation model requires the input of subjective assumptions to calculate the value of stock options. For those assumptions, the Company uses historical data and other information to estimate the expected price volatility and risk-free interest rate for all awards. The expected life of stock options granted are estimated to be five years for employees and six years for directors and executives, based on the Company’s historical experience. Assumptions on the dividend yield are based on the fact that the Company has never paid cash dividends and has no present intention to pay cash dividends. The restricted stock units granted by the Company are measured at the grant-date price of the Company’s common shares. Expense is recognized over the vesting period for all awards and commences at the grant date for time-based awards. Forfeitures are recognized as they occur.

For the Company’s Employee Stock Purchase Plan, the fair value of the right to acquire stock at a discounted price under the plan is calculated using the Black-Scholes valuation model. Expense is recognized over the period the employee contributes to the plan through payroll deductions.

Segment information

As of December 31, 2023, the Company viewed its operations and managed its business as one operating segment consistent with how its chief operating decision-maker, the Chief Executive Officer, makes decisions regarding resource allocation and assessing performance. Substantially all of the Company’s premises, property and equipment are located in the United States.

Comprehensive loss

Comprehensive loss is comprised of net loss and adjustments for the change in unrealized gains and losses on investments in available-for-sale marketable securities. The Company includes comprehensive loss and its components in the consolidated statements of operations and comprehensive loss, net of tax effects if any.

Concentrations of Credit Risk

Financial instruments which potentially subject the Company to credit risk consist primarily of cash, cash equivalents and marketable securities. The Company holds these investments in highly rated financial institutions, and, by policy, limits the amounts of credit exposure to any one financial institution. These amounts at times may exceed federally insured limits. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds. The Company has no off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements.

Recent accounting pronouncements

In June 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments (ASC 326), which changes how entities account for credit losses on financial assets and other instruments that are not measured at fair value through net income, including available-for-sale debt securities. The Company implemented the guidance as of January 1, 2023 and there was not a material impact on its results of operations or financial position.

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (ASC 2023-07), which requires disclosure of significant segment expenses and other segment items on an annual and interim basis under ASC 280. ASU 2023-07 is effective for fiscal years beginning after December 15, 2023, and for interim periods beginning after December 15, 2024. Early adoption is permitted and the amendments in this ASU should be applied on a retrospective basis to all periods presented. The Company has not determined the impact ASU 2023-07 may have on the Company’s financial statement disclosures.

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (ASU 2023-09), which improves income tax disclosures by requiring: (1) consistent categories and greater disaggregation of information in the rate reconciliation, and (2) income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. ASU 2023-09 is effective for annual periods beginning after December 15, 2024. Early adoption is permitted. The ASU indicates that all entities will apply the guidance prospectively with an option for retroactive application to each period presented in the financial statements. The Company has not determined the impact ASU 2023-09 may have on the Company’s financial statement disclosures.

Investments in marketable securities

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Investments in marketable securities

Investments in marketable securities and cash equivalents consisted of the following:


	Amortized Cost		Gross Unrealized Gain(1)		Gross Unrealized Loss(1)		Fair Value
As of December 31, 2023	(in thousands)
Cash equivalents
Money market fund	$	18,029	$	—	$	—	$	18,029
Total	$	18,029	$	—	$	—	$	18,029
Investments in marketable short-term securities
US government agency bonds	$	17,918	$	—	$	(44)	$	17,874
US corporate bonds	71,045		30		(189)		70,886
Yankee bonds	2,000		—		(17)		1,983
US government bonds	9,001		—		(26)		8,975
Total	$	99,964	$	30	$	(276)	$	99,718
Investments in marketable long-term securities

US corporate bonds	$	6,273	$	18	$	(7)	$	6,284

Total	$	6,273	$	18	$	(7)	$	6,284

(1) Gross unrealized gain (loss) is pre-tax and is reported in accumulated other comprehensive loss.


	Amortized Cost		Gross Unrealized Gain(1)		Gross Unrealized Loss(1)		Fair Value
As of December 31, 2022	(in thousands)
Cash equivalents
Money market fund	$	23,218	$	—	$	—	$	23,218
Total	$	23,218	$	—	$	—	$	23,218
Investments in marketable short-term securities
US government agency bonds	$	26,686	$	—	$	(424)	$	26,262
US corporate bonds	27,144		—		$	(303)	$	26,841
US treasury bills	8,483		—		$	(16)	8,467
US government bonds	55,361		—		(794)		54,567
Total	$	117,674	$	—	$	(1,537)	$	116,137
Investments in marketable long-term securities
US government agency bonds	$	3,724	$	—	$	(130)	$	3,594
US corporate bonds	25,433		—		(336)		25,097
US government bonds	8,972		—		(300)		8,672
Total	$	38,129	$	—	$	(766)	$	37,363

(1) Gross unrealized gain (loss) is pre-tax and is reported in accumulated other comprehensive loss.

The contractual maturity of the $99.7 million of short-term marketable securities held by the Company as of December 31, 2023 is less than one year. As of December 31, 2023, the Company held $6.3 million of long-term marketable securities with contractual maturities of more than one year, but less than five years. As of December 31, 2022, the Company’s $116.1 million of short-term marketable securities had contractual maturities of less than one year, while the Company’s $37.4 million of long-term marketable securities had maturities of more than one year, but less than five years.

At December 31, 2023 and December 31, 2022, the Company had 37 and 53, respectively, available-for-sale investment debt securities in an unrealized loss position without an allowance for credit losses. Unrealized losses on the Company’s investments in debt securities have not been recognized into income as the issuers’ bonds are of high credit quality and the decline in fair value is largely due to market conditions and/or changes in interest rates. The Company does not intend to sell and it is more likely than not that the Company will not be required to sell the securities prior to the anticipated recovery of their amortized cost basis. The issuers continue to make timely interest payments on the bonds. The fair value is expected to recover as the bonds approach maturity.

Accrued interest receivable on investments in marketable securities of $0.6 million at both December 31, 2023 and December 31, 2022 is included in prepaid expenses and other current assets.

The Company had realized gains on investments of less than $0.1 million and zero for the years ended December 31, 2023 and 2022,

Fair value measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of assets and liabilities measured at fair value on a recurring basis

The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis, and indicates the fair value hierarchy of the valuation techniques used to determine such fair value:


	Level 1		Level 2		Level 3		Total
As of December 31, 2023	(in thousands)
Assets
Cash and cash equivalents	$	26,285	$	—	$	—	$	26,285
Investments in marketable securities, current	—		99,718		—		99,718
Investments in marketable securities, non-current	—		6,284		—		6,284
Total	$	26,285	$	106,002	$	—	$	132,287
Liabilities
Contingent consideration	—		—		7,600		7,600
Total	$	—	$	—	$	7,600	$	7,600


	Level 1		Level 2		Level 3		Total
As of December 31, 2022	(in thousands)
Assets
Cash and cash equivalents	$	30,776	$	—	$	—	$	30,776
Investments in marketable securities, current	—		116,137		—		116,137
Investments in marketable securities, non-current	—		37,363		—		37,363
Total	$	30,776	$	153,500	$	—	$	184,276
Liabilities
Contingent consideration	—		—		7,531		7,531
Total	$	—	$	—	$	7,531	$	7,531

Schedule of changes in fair value of contingent consideration

The following table presents the changes in fair value of the Company’s contingent consideration:


	Liability at beginning of the period		Increase in fair value of liability		Liability at end of the period
	(in thousands)
Year ended December 31, 2023	$	7,531	$	69	$	7,600
Year ended December 31, 2022	$	5,298	$	2,233	$	7,531

Stock-based compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of stock option activity

The following table summarizes activity related to the Company’s restricted stock units, for the year ended December 31, 2023:


	Restricted Stock Units Outstanding			Vested Restricted Stock Units	Non-Vested Restricted Stock Units
	Number	Weighted-Average Grant-Date Fair Value		Number	Number	Weighted-Average Grant-Date Fair Value
Balance as of December 31, 2022	—	$	—	—	—	$	—
Restricted stock units granted	1,344,550	$	2.90	—	1,344,550	$	2.90
Restricted stock units vested	—	$	—	—	—	$	—
Restricted stock units forfeited, canceled or expired	(113,100)	$	—	—	(113,100)	$	2.90
Restricted stock units vested	—	$	—	—	—	$	—
Balance as of December 31, 2023	1,231,450	$	2.90	—	1,231,450	$	2.90

Schedule of allocation of stock-based compensation

Stock-based compensation has been recorded in the consolidated statement of operations and comprehensive loss as follows:


	Year Ended December 31,
	2023		2022
	(in thousands)
Research and development	$	3,684	$	2,912
General and administrative	5,617		4,270
Total	$	9,301	$	7,182

Liability classified stock options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of stock option activity

Arbutus Plans

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Schedule of stock option activity

The following table summarizes activity related to the Company’s equity-classified stock options, including its performance options, for the year ended December 31, 2023:


	Stock Options Outstanding			Vested Stock Options	Non-Vested Stock Options
	Number	Weighted-Average Exercise Price		Number	Number	Weighted-Average Grant-Date Fair Value
Balance as of December 31, 2022	15,349,998	$	3.76	9,631,779	5,718,219	$	2.39
Options granted	5,082,640	$	2.78	—	5,082,640	$	2.15
Options exercised	(101,356)	$	2.56	(101,356)	—	$	—
Options forfeited, canceled or expired	(1,267,117)	$	4.39	(698,937)	(568,180)	$	2.24
Options vested	—	$	—	3,500,403	(3,500,403)	$	2.33
Balance as of December 31, 2023	19,064,165	$	3.47	12,331,889	6,732,276	$	2.25

The following table summarizes additional information related to the Company’s equity-classified stock options, including its performance options, as of December 31, 2023:


	As of December 31, 2023
Options outstanding and expected to vest
Number of stock options outstanding	19,064,165
Weighted-average exercise price	$	3.47
Intrinsic value (in $000s)	$	857
Weighted-average term remaining	7.0 years
Vested stock options
Number of vested stock options	12,331,889
Weighted-average exercise price	$	3.74
Intrinsic value (in $000s)	$	657
Weighted-average term remaining	6.2 years

Schedule of weighted average Black-Scholes option-pricing assumptions and resultant fair values

The assumptions used in the Black-Scholes option-pricing for grants made during the years ended December 31, 2023 and 2022 are as follows:


	December 31, 2023		December 31, 2022
Expected average option term	5.6 years		5.5 years
Expected volatility	97.1	%	97.0	%
Expected dividends	—	%	—	%
Risk-free interest rate	3.57	%	1.77	%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Investment in Genevant (Details)	12 Months Ended
Investment in Genevant (Details)	Dec. 31, 2023 USD ($)
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 0
Genevant
Schedule of Equity Method Investments [Line Items]
Sub-licensing revenue, percentage	20.00%
Bona fide collaboration Percentage [Member]	14.00%
Equity method investments	$ 0
Ownership interest in equity method investment (as a percent)	16.00%

Contingencies and commitments	12 Months Ended
Contingencies and commitments	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Contingencies and commitments	Contingencies and commitments Stock Purchase Agreement with Enantigen In October 2014, Arbutus Inc., the Company’s wholly-owned subsidiary, acquired all of the outstanding shares of Enantigen Therapeutics, Inc. (Enantigen) pursuant to a stock purchase agreement. The amount paid to Enantigen’s selling shareholders could be up to an additional $102.5 million in sales performance milestones in connection with the sale of the first commercialized product by Arbutus for the treatment of HBV, regardless of whether such product is based upon assets acquired under this agreement, and a low single-digit royalty on net sales of such first commercialized HBV product, up to a maximum royalty payment of $1.0 million that, if paid, would be offset against Arbutus’ milestone payment obligations. Certain other development milestones related to the acquisition were tied to programs which are no longer under development by Arbutus, and therefore the contingency related to those development milestones is zero. The contingent consideration is a financial liability and is measured at its fair value at each reporting period, with any changes in fair value from the previous reporting period recorded in the statement of operations and comprehensive loss (note 3). The fair value of the contingent consideration was $7.6 million as of December 31, 2023.

Investments in marketable securities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) numberOfSegments	Dec. 31, 2022 USD ($) numberOfSegments
Debt Securities, Available-for-sale [Line Items]
Cash Equivalents, Amortized Cost	$ 26,285	$ 30,776
Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent	6,273	38,129
Debt Securities, Noncurrent	(6,300)	(37,400)
Debt Securities, Realized Gain (Loss)	$ 100	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions \| numberOfSegments	37	53
Accrued Investment Income Receivable	$ 600	$ 600
Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	99,964	117,674
Gross Unrealized Gain	30	0
Gross Unrealized Loss	(276)	(1,537)
Fair Value	99,718	116,137
Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gain	18	0
Gross Unrealized Loss	(7)	(766)
Debt Securities, Noncurrent	(6,284)	(37,363)
Money market fund
Debt Securities, Available-for-sale [Line Items]
Cash Equivalents, Amortized Cost	18,029	23,218
Cash Equivalents, Fair Value	18,029	23,218
US government agency bonds
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent		3,724
US government agency bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	17,918	26,686
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(44)	(424)
Fair Value	17,874	26,262
US government agency bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gain		0
Gross Unrealized Loss		(130)
Debt Securities, Noncurrent		(3,594)
US corporate bonds
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent	6,273	25,433
US corporate bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	71,045	27,144
Gross Unrealized Gain	30	0
Gross Unrealized Loss	(189)	(303)
Fair Value	70,886	26,841
US corporate bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gain	18	0
Gross Unrealized Loss	(7)	(336)
Debt Securities, Noncurrent	(6,284)	(25,097)
Yankee Bonds [Member] \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	2,000
Gross Unrealized Gain	0
Gross Unrealized Loss	(17)
Fair Value	1,983
US government bonds
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Loss		(300)
Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent		8,972
Debt Securities, Noncurrent		(8,672)
US government bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current	9,001	55,361
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(26)	(794)
Fair Value	$ 8,975	54,567
US government bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gain		0
US Treasury Bill Securities [Member] \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Amortized Cost, Current		8,483
Gross Unrealized Gain		0
Gross Unrealized Loss		(16)
Fair Value		$ 8,467

Stock-based compensation - Outstanding options under the Oncore Option Plan (Details) - OnCore Option Plan	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Number of optioned common shares
Balance - Number of optioned common shares (in shares) \| shares	80,600
Weighted average exercise price
Balance - Weighted average exercise price (in CAD and USD per share) \| $ / shares	$ 0.56

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	Ernst & Young LLP
Auditor Location	Philadelphia, Pennsylvania
Auditor Firm ID	42

Collaborations and royalty entitlements

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

Collaborations and royalty entitlements

Collaborations

Qilu Pharmaceuticals Co, Ltd.

In December 2021, the Company entered into a technology transfer and exclusive licensing agreement (the License Agreement) with Qilu, pursuant to which the Company granted Qilu an exclusive (except as to certain retained rights), sublicensable, royalty-bearing license, under certain intellectual property owned by the Company, to develop, manufacture and commercialize imdusiran, including pharmaceutical products that include imdusiran, for the treatment or prevention of hepatitis B in China, Hong Kong, Macau and Taiwan (the Territory).

In partial consideration for the rights granted by the Company, Qilu paid the Company a one-time upfront cash payment of $40.0 million on January 5, 2022 and agreed to pay the Company milestone payments totaling up to $245 million, net of withholding taxes, upon the achievement of certain technology transfer, development, regulatory and commercialization milestones (the Milestone Payments). Qilu paid $4.4 million of withholding taxes to the Chinese taxing authority on the Company’s behalf, related to the upfront cash payment. In addition, Qilu also agreed to pay the Company double digit royalties into the low twenties percent based upon annual net sales of imdusiran in the Territory. The royalties are payable on a product-by-product and region-by-region basis, subject to certain limitations.

Qilu is responsible for all costs related to developing, obtaining regulatory approval for, and commercializing imdusiran for the treatment or prevention of hepatitis B in the Territory. Qilu is required to use commercially reasonable efforts to develop, seek regulatory approval for, and commercialize at least one imdusiran product candidate in the Territory. A joint development committee has been established between the Company and Qilu to coordinate and review the development, manufacturing and commercialization plans. Both parties also have entered into a supply agreement and related quality agreement pursuant to which the Company will manufacture or have manufactured and supply Qilu with all quantities of imdusiran necessary for Qilu to develop and commercialize in the Territory until the Company has completed manufacturing technology transfer to Qilu and Qilu has received all approvals required for it or its designated contract manufacturing organization to manufacture imdusiran in the Territory.

Concurrent with the execution of the license agreement, the Company entered into a Share Purchase Agreement (the Share Purchase Agreement) with Anchor Life Limited, a company established pursuant to the applicable laws and regulations of Hong Kong and an affiliate of Qilu (the Investor), pursuant to which the Investor purchased 3,579,952 of the Company’s common shares, without par value (the Common Shares), at a purchase price of USD $4.19 per share, which was a 15% premium on the thirty-day average closing price of the Common Shares as of the close of trading on December 10, 2021 (the Share Transaction). The Company received $15.0 million of gross proceeds from the Share Transaction on January 6, 2022. The Common Shares sold to the Investor in the Share Transaction represented approximately 2.5% of the Common Shares outstanding immediately prior to the execution of the Share Purchase Agreement.

The License Agreement falls under the scope of ASC 808 as both parties are active participants in the arrangement and are exposed to significant risks and rewards. While this arrangement is in the scope of ASC 808, the Company analogizes to ASC 606 for some aspects of this arrangement, including for the delivery of a good or service (i.e., a unit of account). In accordance with the guidance, the Company identified the following commitments under the arrangement: (i) rights to develop, use, sell, have sold, offer for sale and import any product comprised of Licensed Product (the Qilu License); and (ii) drug supply

obligations and manufacturing technology transfer (the Manufacturing Obligations). The Company determined that these two commitments are not distinct performance obligations for purposes of recognizing revenue as the manufacturing process is highly specialized and Qilu would not be able to benefit from the Qilu License without the Company’s involvement in the manufacturing activities until the transfer of the manufacturing know-how is complete. As such, the Company will combine these commitments into one performance obligation to which the transaction price will be allocated to and will recognize this transaction price associated with the bundled performance obligation over time using an inputs method based on labor hours expended by the Company on its Manufacturing Obligations.

The Company determined the initial transaction price of the combined performance obligation to be $50.4 million, which includes the $40.0 million upfront fee, $4.4 million of withholding taxes paid by Qilu on behalf of the Company and the premium paid for the Share Transaction of $4.1 million. The Company determined the Milestone Payments to be variable consideration subject to constraint at inception. At the end of each subsequent reporting period, the Company will reevaluate the probability of achievement of the future development, regulatory, and sales milestones subject to constraint and, if necessary, will adjust its estimate of the overall transaction price. Any such adjustments will be recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment.

The following table outlines the transaction price and the changes to the related liability balance:


	Transaction Price		Cumulative Collaboration Revenue Recognized		Deferred License Revenue
	(in thousands)
Combined performance obligation	$	50,445	$	36,681	$	13,764
Less contract asset					$	(1,973)
Total deferred license revenue					$	11,791

The Company recognized $10.7 million of revenue based on labor hours expended by the Company on its Manufacturing Obligations during the twelve months ended December 31, 2023, and $26.0 million during the twelve months ended December 31, 2022.

As of December 31, 2023, the balance of the deferred license revenue was $11.8 million. The $4.4 million of withholding taxes paid by Qilu on behalf of the Company was recorded as income tax expense during the twelve months ended December 31, 2022.

The Company incurred $0.6 million of incremental costs in obtaining the Qilu License, which the Company capitalized in other current assets and other assets and amortizes as a component of general and administrative expense commensurate with the recognition of the combined performance obligation. The Company recognized $0.1 million of related amortization expense for the twelve months ended December 31, 2023.

The Company reevaluates the transaction price and the total estimated labor hours expected to be incurred to satisfy the performance obligations and adjusts the deferred revenue at the end of each reporting period. Such changes will result in a change to the amount of collaboration revenue recognized and deferred revenue.

Assembly Biosciences, Inc.

In August 2020, the Company entered into a clinical collaboration agreement with Assembly Biosciences, Inc. (Assembly) to evaluate imdusiran in combination with Assembly’s first-generation HBV core inhibitor (capsid inhibitor) candidate vebicorvir (VBR) and standard-of-care NA therapy for the treatment of patients with HBV infection. Assembly has completed enrollment in the clinical trial. In July 2022, Assembly announced its plan to discontinue development of VBR. Despite this, in consultation with Assembly, the Company continued dosing patients in this Phase 2a proof-of-concept clinical trial in order to fully and accurately assess the results. Preliminary data from 65 patients indicated that adding VBR to imdusiran and NA therapy does not positively or negatively impact the reduction of HBsAg compared to imdusiran and NA therapy alone. Accordingly, the Company and Assembly mutually agreed to discontinue the clinical trial following completion of the final, on-

treatment visit at week 48. The Company and Assembly shared in the costs of the collaboration. The Company incurred $1.3 million and $2.8 million of costs related to the collaboration during the years ended December 31, 2023 and 2022, respectively, and reflected those costs in research and development in the statements of operations and comprehensive loss. Except to the extent necessary to carry out Assembly’s responsibilities with respect to the collaboration trial, the Company has not provided any license grant to Assembly for use of the Company’s imdusiran compound.

Barinthus Biotherapeutics plc

In July 2021, the Company entered into a clinical collaboration agreement with Barinthus Biotherapeutics plc (Barinthus), formerly Vaccitech plc, to evaluate imdusiran followed by Barinthus’ VTP-300, an HBV antigen specific immunotherapy, and ongoing nucleos(t)ide analogue therapy in patients with cHBV infection. Recently, the clinical trial was amended and is now dosing patients in an additional treatment arm that includes an approved PD-1 monoclonal antibody inhibitor, nivolumab (Opdivo®).

The Company is responsible for managing this Phase 2a proof-of-concept clinical trial, subject to oversight by a joint development committee comprised of representatives from the Company and Barinthus. The Company and Barinthus retain full rights to their respective product candidates and will split all costs associated with the clinical trial. The Company incurred $1.8 million and $0.8 million of costs related to the collaboration, net of Barinthus’s 50% share, during the years ended December 31, 2023 and 2022, respectively, and reflected those net costs in research and development in the statements of operations and comprehensive loss.

Royalty Entitlements

Alnylam Pharmaceuticals, Inc. and Acuitas Therapeutics, Inc.

The Company has two royalty entitlements to Alnylam’s global net sales of ONPATTRO.

In 2012, the Company entered into a license agreement with Alnylam Pharmaceuticals, Inc. (Alnylam) that entitles Alnylam to develop and commercialize products with the Company’s LNP technology. Alnylam’s ONPATTRO, which represents the first approved application of the Company’s LNP technology, was launched by Alnylam in 2018. Under the terms of this license agreement, the Company is entitled to tiered royalty payments on global net sales of ONPATTRO ranging from 1.00% - 2.33% after offsets, with the highest tier applicable to annual net sales above $500 million. This royalty interest was sold to OMERS, effective as of January 1, 2019, for $20 million in gross proceeds before advisory fees. OMERS will retain this entitlement until it has received $30 million in royalties, at which point 100% of this royalty entitlement on future global net sales of ONPATTRO will revert back to the Company. OMERS has assumed the risk of collecting up to $30.0 million of future royalty payments from Alnylam and the Company is not obligated to reimburse OMERS if they fail to collect any such future royalties. If this royalty entitlement reverts to the Company, it has the potential to provide an active royalty stream or to be otherwise monetized again in full or in part. From the inception of the royalty sale through December 31, 2023, an aggregate of $22.7 million of royalties have been earned by OMERS. See note 9 for further details.

The Company also has rights to a second royalty interest ranging from 0.75% to 1.125% on global net sales of ONPATTRO, with 0.75% applying to sales greater than $500 million, originating from a settlement agreement and subsequent license agreement with Acuitas Therapeutics, Inc. (Acuitas). This royalty entitlement from Acuitas has been retained by the Company and was not part of the royalty entitlement sale to OMERS.

Gritstone Oncology, Inc.

On October 16, 2017, the Company entered into a license agreement with Gritstone that granted them worldwide access to its portfolio of proprietary and clinically validated LNP technology and associated intellectual property to deliver Gritstone’s self-replicating, non-mRNA, RNA-based neoantigen immunotherapy products. Gritstone paid the Company an upfront payment, and will make payments for achievement of development, regulatory, and commercial milestones and royalties. As a result of the Company’s agreement with Genevant (see note 5 for details), from April 11, 2018 going forward, Genevant is entitled to 50% of the revenues earned by the Company from Gritstone. The Company is the agent in this arrangement and records revenue on a net basis. Milestone payments that are not within the control of the Company or the licensee, such as those that require regulatory approvals, are not considered probable of being achieved until those approvals are received. The Company did not receive any payments from Gritstone during the years ended December 31, 2023 or 2022.

Revenues from the Company’s royalty entitlements are summarized in the following table:


	Year ended December 31,
	2023		2022
	(in thousands)
Revenue from collaborations and licenses
Royalties from sales of Onpattro	$	3,608	$	5,316
Qilu Pharmaceutical Co., Ltd.	10,666		26,015
Other milestone and royalty payments	—		35
Non-cash royalty revenue
Royalties from sales of Onpattro	3,867		7,653
Total revenue	$	18,141	$	39,019

Significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Schedule of estimated useful lives of property and equipment

The Company records depreciation using the straight-line method over the estimated useful lives of the capital assets as follows:


	Useful Life (Years)
Laboratory equipment		5
Computer and office equipment	2	to	5
Furniture and fixtures		5

Consolidated Statement of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Shares	Additional paid-in capital	Deficit	Accumulated other comprehensive loss
Shares, Issued, Beginning Balance at Dec. 31, 2021		144,987,736
Beginning balance at Dec. 31, 2021	$ 169,439	$ 1,286,636	$ 65,485	$ (1,134,347)	$ (48,335)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	7,182		7,182
Certain fair value adjustments to liability stock option awards	26		26
Issuance of common shares pursuant to the Open Market Sales Agreement (in shares)		8,645,426
Issuance of common shares pursuant to the Open Market Sales Agreement	$ 20,324	$ 20,324
Issuance of common shares pursuant to exercise of ESPP options (in shares)	171,224	171,224
Issuance of common shares pursuant to exercise of ESPP	$ 395	$ 588	(193)
Issuance of common shares pursuant to Share Purchase Agreement (in shares)		3,579,952
Issuance of common shares pursuant to exercise of stock options	10,973	$ 10,973
Issuance of common shares pursuant to exercise of options (in shares)		71,025
Issuance of common shares pursuant to exercise of stock options	122	$ 216	(94)
Unrealized gain (loss) on available-for-sale securities	(2,153)				(2,153)
Net loss	(69,456)			(69,456)
Ending balance (in shares) at Dec. 31, 2022		157,455,363
Ending balance at Dec. 31, 2022	136,852	$ 1,318,737	72,406	(1,203,803)	(50,488)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	9,301		9,301
Issuance of common shares pursuant to the Open Market Sales Agreement (in shares)		12,020,257
Issuance of common shares pursuant to the Open Market Sales Agreement	$ 29,852	$ 29,852
Issuance of common shares pursuant to exercise of ESPP options (in shares)	290,438	290,438
Issuance of common shares pursuant to exercise of ESPP	$ 535	$ 774	(239)
Issuance of common shares pursuant to exercise of options (in shares)		101,356
Issuance of common shares pursuant to exercise of stock options	260	$ 458	(198)
Unrealized gain (loss) on available-for-sale securities	2,067				2,067
Net loss	(72,849)			(72,849)
Ending balance (in shares) at Dec. 31, 2023		169,867,414
Ending balance at Dec. 31, 2023	$ 106,018	$ 1,349,821	$ 81,270	$ (1,276,652)	$ (48,421)

Consolidated Balance Sheets (Parenthetical) - shares	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common shares, shares issued (in shares)	169,867,414	157,455,363
Common shares, shares outstanding (in shares)	169,867,414	157,455,363

Organization (Details) - USD ($)	Jan. 05, 2022	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash, cash equivalents and short-term investments		$ 132,300,000
Outstanding debt		$ 0
One-Time Upfront Cash Payment \| Qilu
Class of Stock [Line Items]
Cash payment for collaborations	$ 40,000,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 272
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-Section 45
-Paragraph 3
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-URI https://asc.fasb.org//1943274/2147483014/272-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-Subparagraph (SX 210.4-08(d))
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Income taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income taxes

The Company is subject to taxation and files income tax returns in Canadian federal and provincial, United States federal and several state jurisdictions. In December 2022, the United States Internal Revenue service completed its examination of the Company’s federal tax return for 2018. In May 2022, The Canada Revenue Agency completed its examination of the Company’s Canadian tax returns for 2018 and 2019, with no adjustments proposed.


	Year ended December 31,
	2023		2022
	(in thousands)
Computed taxes (benefits) at Canadian federal and provincial tax rates	$	(19,668)	$	(17,554)
Withholding taxes	—		4,444
Other	(2,108)		761
Permanent and other differences	198		869
Federal R&D credit	(1,741)		—
Foreign tax credit applied	—		(4,444)
Federal and Provincial ITCs applied	(179)		(324)
Change in valuation allowance	18,425		14,563
Difference due to income taxed at foreign rates	5,260		5,625
Stock-based compensation	(187)		504
Income tax expense	$	—	$	4,444

As of December 31, 2023, the Company had investment tax credits available to reduce Canadian federal income taxes of $7.1 million, versus $7.2 million as of December 31, 2022, which expire between 2031 and 2037, and provincial income taxes of $2.0 million as of both December 31, 2023 and 2022, which expire between 2024 and 2027. The investment tax credits are accounted for under a flow-through method. In addition, the Company had research and development credits of $7.3 million as of December 31, 2023, and $3.7 million as of December 31, 2022, which expire between 2031 and 2038 and which can be used to reduce future taxable income in the United States.

As of December 31, 2023, the Company had scientific research and experimental development expenditures of $61.9 million available for indefinite carry-forward, versus $62.2 million as of December 31, 2022. The Company also had net operating

losses of $148.1 million as of both December 31, 2023 and 2022, which are due to expire between 2035 and 2038 and which can be used to offset future taxable income in Canada.

As of December 31, 2023 and 2022, the Company had $11.7 million of net operating losses due to expire in 2035 which can be used to offset future taxable income in the United States. United States net operating loss carryforwards arising in 2019 and future periods have an indefinite carryforward period. As of December 31, 2023, the Company had $230.2 million of net operating losses subject to an indefinite carryforward period which can be used to offset future taxable income in the United States. Future use of a portion of the United States loss carryforwards are subject to limitations under Internal Revenue Code Section 382.

As a result of ownership changes occurring on October 1, 2014 and March 4, 2015, the Company’s ability to use these losses may be limited. Losses incurred to date may be further limited if a subsequent change in control occurs.

The Company generated $14.8 million of pre-tax domestic income and $87.7 million in pre-tax foreign losses, respectively, for the year ended December 31, 2023. The Company generated $28.7 million of pre-tax domestic income and $93.7 million in pre-tax foreign losses, respectively, for the year ended December 31, 2022. The Company used accumulated domestic net operating losses to offset the taxable income in both years.

As required by the 2017 Tax Cuts and Jobs Act and effective in 2022, the deferred tax asset as of December 31, 2023 and 2022 included $27.3 million and $16.5 million, respectively, related to the mandatory capitalization and amortization of research and development expenses.

Significant components of the Company’s deferred tax assets and liabilities are shown below:


	As of December 31,
	2023		2022
	(in thousands)
Deferred tax assets (liabilities):
Operating loss carryforwards	$	89,090	$	83,564
Canadian research and development deductions	16,726		16,791
Book amortization in excess of tax	(451)		(461)
Revenue recognized for tax purposes in excess of revenue recognized for accounting purposes	1,878		2,799
Tax value in excess of accounting value in lease inducements	74		93
Deferred revenue	3,184		6,063
Canadian Federal investment tax credits	5,147		5,278
Canadian Provincial investment tax credits	1,953		1,953
Equity method investment	3,375		3,375
U.S. Federal research and development credits	7,254		3,633
Deductible stock options	6,058		3,681
U.S. research and experimental expenditures capitalization	27,265		16,471
Accrued interest payable	1,722		1,507
Amortization	322		387
Other	114		153
Total deferred tax assets	$	163,711	$	145,287
Valuation allowance	(163,711)		(145,287)
Net deferred tax assets (liabilities)	$	—	$	—

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
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-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
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-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
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-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Fair value measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair value measurements

The Company measures certain financial instruments and other items at fair value.

To determine the fair value, the Company uses the fair value hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are inputs market participants would use to value an asset or liability and are developed based on market data obtained from independent sources. Unobservable inputs are inputs based on assumptions about the factors market participants would use to value an asset or liability. The three levels of inputs that may be used to measure fair value are as follows:

•Level 1 inputs are quoted market prices for identical instruments available in active markets. The Company’s cash and cash equivalents are measured using Level 1 inputs.

•Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability either directly or indirectly. If the asset or liability has a contractual term, the input must be observable for substantially the full term. An example includes quoted market prices for similar assets or liabilities in active markets. The Company’s investments in marketable securities are measured using Level 2 inputs.

•Level 3 inputs are unobservable inputs for the asset or liability and will reflect management’s assumptions about market assumptions that would be used to price the asset or liability. The Company’s liability-classified options and contingent consideration are measured using Level 3 inputs.

Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. Changes in the observability of valuation inputs may result in a reclassification of levels for certain securities within the fair value hierarchy.

The carrying values of cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximate their fair values due to the immediate or short-term maturity of these financial instruments.

To determine the fair value of the contingent consideration (note 10), the Company uses a probability weighted assessment that considers the likelihood of successfully commercializing a treatment for cHBV, the timing of future revenues related to commercial sales, and a probability adjusted discount rate that reflects the early stage nature of the development program, time to complete the program development, and overall biotech indices. The Company determined that the fair value of the contingent consideration was $7.6 million as of December 31, 2023 and the increase of $0.1 million has been recorded within operating expenses in the statement of operations and comprehensive loss for the year ended December 31, 2023. The assumptions used in the discounted cash flow model are level 3 inputs as defined above. The Company assessed the sensitivity of the fair value measurement to changes in these unobservable inputs, and determined that changes within a reasonable range would not result in a materially different assessment of fair value.


	Level 1		Level 2		Level 3		Total
As of December 31, 2023	(in thousands)
Assets
Cash and cash equivalents	$	26,285	$	—	$	—	$	26,285
Investments in marketable securities, current	—		99,718		—		99,718
Investments in marketable securities, non-current	—		6,284		—		6,284
Total	$	26,285	$	106,002	$	—	$	132,287
Liabilities
Contingent consideration	—		—		7,600		7,600
Total	$	—	$	—	$	7,600	$	7,600


	Level 1		Level 2		Level 3		Total
As of December 31, 2022	(in thousands)
Assets
Cash and cash equivalents	$	30,776	$	—	$	—	$	30,776
Investments in marketable securities, current	—		116,137		—		116,137
Investments in marketable securities, non-current	—		37,363		—		37,363
Total	$	30,776	$	153,500	$	—	$	184,276
Liabilities
Contingent consideration	—		—		7,531		7,531
Total	$	—	$	—	$	7,531	$	7,531

The following table presents the changes in fair value of the Company’s contingent consideration:


	Liability at beginning of the period		Increase in fair value of liability		Liability at end of the period
	(in thousands)
Year ended December 31, 2023	$	7,531	$	69	$	7,600
Year ended December 31, 2022	$	5,298	$	2,233	$	7,531

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Income taxes - Income tax reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Computed taxes (benefits) at Canadian federal and provincial tax rates	$ (19,668)	$ (17,554)
Withholding taxes	0	4,444
Other	(2,108)	761
Permanent and other differences	198	869
Federal R&D credit	(1,741)	0
Foreign tax credit applied	0	(4,444)
Federal and Provincial ITCs applied	(179)	(324)
Change in valuation allowance	18,425	14,563
Difference due to income taxed at foreign rates	5,260	5,625
Stock-based compensation	(187)	504
Income tax expense	0	4,444
Deferred tax assets, operating loss carryforwards, subject to expiration	$ 11,700	$ 11,700

Shareholders’ equity	12 Months Ended
Shareholders’ equity	Dec. 31, 2023
Equity [Abstract]
Shareholders' equity	Shareholders’ equity Authorized share capital The Company’s authorized share capital consists of an unlimited number of common shares and preferred shares, without par value, and 1,164,000 Series A participating convertible preferred shares, without par value. Open Market Sale Agreement The Company has an Open Market Sale Agreement with Jefferies LLC (Jefferies) dated December 20, 2018, as amended by Amendment No. 1, dated December 20, 2019, Amendment No. 2, dated August 7, 2020 and Amendment No. 3, dated March 4, 2021 (as amended, the Sale Agreement), under which the Company may issue and sell common shares, from time to time. On December 23, 2019, the Company filed a shelf registration statement on Form S-3 with the Securities and Exchange Commission (the SEC) (File No. 333-235674) and accompanying base prospectus, which was declared effective by the SEC on January 10, 2020 (the January 2020 Registration Statement), for the offer and sale of up to $150.0 million of the Company’s securities. The January 2020 Registration Statement also contained a prospectus supplement in connection with the offering of up to $50.0 million of the Company’s common shares pursuant to the Sale Agreement. This prospectus supplement was fully utilized during 2020. On August 7, 2020, the Company filed a prospectus supplement with the SEC (the August 2020 Prospectus Supplement) in connection with the offering of up to an additional $75.0 million of its common shares pursuant to the Sale Agreement under the January 2020 Registration Statement. The August 2020 Prospectus Supplement was fully utilized during 2020. The January 2020 Registration Statement expired in January 2023. On August 28, 2020, the Company filed a shelf registration statement on Form S-3 with the SEC (File No. 333-248467) and accompanying base prospectus, which was declared effective by the SEC on October 22, 2020 (the October 2020 Registration Statement), for the offer and sale of up to $200.0 million of the Company’s securities. On March 4, 2021, the Company filed a prospectus supplement with the SEC (the March 2021 Prospectus Supplement) in connection with the offering of up to an additional $75.0 million of its common shares pursuant to the Sale Agreement under October 2020 Registration Statement. The March 2021 Prospectus Supplement was fully utilized during 2021. On October 8, 2021, the Company filed a prospectus supplement with the SEC (the October 2021 Prospectus Supplement) in connection with the offering of up to an additional $75.0 million of its common shares pursuant to the Sale Agreement under the October 2020 Registration Statement. The October 2020 Registration Statement expired in October 2023 with $29.3 million that was not utilized under the October 2021 Prospectus Supplement. On November 4, 2021, the Company filed a shelf registration statement on Form S-3 with the SEC (File No. 333-260782) and accompanying base prospectus, declared effective by the SEC on November 18, 2021 (the November 2021 Registration Statement), for the offer and sale of up to $250.0 million of the Company’s securities. On March 3, 2022, the Company filed a prospectus supplement with the SEC (the March 2022 Prospectus Supplement) in connection with the offering of up to an additional $100.0 million of its common shares pursuant to the Sale Agreement under: (i) the January 2020 Registration Statement; (ii) the October 2020 Registration Statement; and (iii) the November 2021 Registration Statement, of which only the November 2021 Registration Statement remains active. During the years ended December 31, 2023 and 2022, the Company issued 12,020,257 and 8,645,426 common shares, respectively, under the Sale Agreement, resulting in net proceeds of approximately $29.9 million and $20.3 million, respectively. As of December 31, 2023, there was approximately $70.9 million remaining available under the March 2022 Prospectus Supplement, pursuant to the November 2021 Registration Statement.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

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+ Details

Significant accounting policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Basis of presentation

Principles of consolidation

All intercompany balances and transactions have been eliminated. Certain prior year amounts have been reclassified to conform to the current year presentation.

Use of estimates

Cash and cash equivalents

Investments in marketable securities

All investments are governed by the Company’s Investment Policy approved by the Company’s board of directors.

Foreign currency translation and functional currency conversion

Investment in Genevant

Property and equipment


	Useful Life (Years)
Laboratory equipment		5
Computer and office equipment	2	to	5
Furniture and fixtures		5

Leasehold improvements are depreciated over their estimated useful lives but in no case longer than the lease term, except where lease renewal is reasonably assured.

Impairment of property and equipment

Revenue from collaborations and licenses

Leases

Research and development costs

Research and development costs that are paid in advance of performance or receipt are recorded as prepaid expense and are amortized over the period that the services are performed.

Net loss attributable to common shareholders per share

Net loss per share

Deferred income taxes

Stock-based compensation

Segment information

Comprehensive loss

Concentrations of Credit Risk

Recent accounting pronouncements

Leases - Maturity of lease liability (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Leases [Abstract]
2024	$ 616
2025	635
2026	654
2027	134
2028	0
Thereafter	0
Total lease payments	2,039
Less: interest	(271)
Present value of lease payments	$ 1,768

Stock-based compensation - Stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 9,301	$ 7,182
Stock-based compensation expense related to ESPP	200	200
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,684	2,912
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,617	$ 4,270

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Sale of future royalties

12 Months Ended

Dec. 31, 2023

Other Liabilities Disclosure [Abstract]

Sale of future royalties

On July 2, 2019, the Company entered into a Purchase and Sale Agreement (the Agreement) with the Ontario Municipal Employees Retirement System (OMERS), pursuant to which the Company sold to OMERS part of its royalty interest on future global net sales of ONPATTRO® (Patisiran) (ONPATTRO), an RNA interference therapeutic currently being sold by Alnylam Pharmaceuticals, Inc. (Alnylam).

ONPATTRO utilizes Arbutus’s LNP technology, which was licensed to Alnylam pursuant to the Cross-License Agreement, dated November 12, 2012, by and between the Company and Alnylam (the LNP License Agreement). Under the terms of the LNP License Agreement, the Company is entitled to tiered royalty payments on global net sales of ONPATTRO ranging from 1.00% to 2.33% after offsets, with the highest tier applicable to annual net sales above $500 million. This royalty interest was sold to OMERS, effective as of January 1, 2019, for $20 million in gross proceeds before advisory fees. OMERS will retain this entitlement until it has received $30 million in royalties, at which point 100% of such royalty interest on future global net sales of ONPATTRO will revert to the Company. OMERS has assumed the risk of collecting up to $30 million of future royalty payments from Alnylam and Arbutus is not obligated to reimburse OMERS if they fail to collect any such future royalties.

The $30 million in royalties to be paid to OMERS is accounted for as a liability, with the difference between the liability and the gross proceeds received accounted for as a discount. The discount, as well as $1.5 million of transaction costs, will be amortized as interest expense based on the projected balance of the liability as of the beginning of each period. As of December 31, 2023, the Company estimated an effective annual interest rate of approximately 2.1%. Over the course of the Agreement, the actual interest rate will be affected by the amount and timing of royalty revenue recognized and changes in the timing of forecasted royalty revenue. On a quarterly basis, the Company will reassess the expected timing of the royalty revenue, recalculate the amortization and effective interest rate and adjust the accounting prospectively as needed.

The Company recognizes non-cash royalty revenue related to the sales of ONPATTRO during the term of the Agreement. As royalties are remitted to OMERS from Alnylam, the balance of the recognized liability is effectively repaid over the life of the Agreement. From the inception of the royalty sale through December 31, 2023, an aggregate of $22.7 million of royalties have been collected by OMERS. There are a number of factors that could materially affect the amount and timing of royalty payments from Alnylam, none of which are within the Company’s control.

During the year ended December 31, 2023, the Company recognized non-cash royalty revenue of $3.9 million and $0.5 million of related non-cash interest expense. During the year ended December 31, 2022, the Company recognized non-cash royalty revenue of $7.7 million and related non-cash interest expense of $1.7 million.

The table below shows the activity related to the net liability for the years ended December 31, 2023 and December 31, 2022:


	Twelve Months Ended December 31,
	2023		2022
	(in thousands)
Net liability related to sale of future royalties - beginning balance	$	10,365	$	16,296
Non-cash royalty revenue	(3,867)		(7,653)
Non-cash interest expense	455		1,722
Net liability related to sale of future royalties - ending balance	$	6,953	$	10,365

In addition to the royalty from the LNP License Agreement, the Company is also receiving a second royalty interest ranging from 0.75% to 1.125% on global net sales of ONPATTRO, with 0.75% applying to sales greater than $500 million, originating from a settlement agreement and subsequent license agreement with Acuitas Therapeutics, Inc. (Acuitas). The royalty from Acuitas has been retained by the Company and was not part of the royalty sale to OMERS.

Stock-based compensation - Stock options outstanding under the Arbutus Plan (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares
Stock Option
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	19,164,765
Arbutus Plans \| Stock Option
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options outstanding (in shares)	19,064,165
Options outstanding, Weighted average exercise price (in USD per share) \| $ / shares	$ 3.47
Intrinsic value of stock options \| $	$ 857
Weighted-average term remaining	7 years
Arbutus Plans \| Vested [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options outstanding (in shares)	12,331,889
Options outstanding, Weighted average exercise price (in USD per share) \| $ / shares	$ 3.74
Intrinsic value of stock options \| $	$ 657
Weighted-average term remaining	6 years 2 months 12 days

Significant accounting policies - Narrative (Details) shares in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) subsidiary segment shares	Dec. 31, 2022 shares
Accounting Policies [Abstract]
Number of wholly-owned subsidiaries \| subsidiary	1
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Equity method investments \| $	$ 0
Number of operating segments \| segment	1
Anti-dilutive common shares excluded from calculation of income per common share (in shares) \| shares	20.4
Stock Option \| Directors and Executives
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Expected life	6 years
Stock Option \| Employee
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Expected life	5 years
Stock Option
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Anti-dilutive common shares excluded from calculation of income per common share (in shares) \| shares		15.5
Genevant
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Ownership interest in equity method investment (as a percent)	16.00%
Equity method investments \| $	$ 0

Stock-based compensation - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Jul. 10, 2023	Jun. 30, 2019	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares reserved for issuance			1,500,000
Discount rate on shares			15.00%
Issuance of common shares pursuant to exercise of ESPP options (in shares)			290,438	171,224
Number of shares remaining for issuance			842,001
Stock-based compensation expense related to ESPP			$ 200	$ 200
Stock-based compensation expense			$ 9,301	$ 7,182
Share-Based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.33%
Share-Based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.33%
Share-Based Payment Arrangement, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			33.33%
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation expense			$ 10,600
Unearned compensation expense, recognition period			2 years 3 months 18 days
Collier Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)		1,112,000
Naftzger Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	500,000
Arbutus Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life			5 years 7 months 6 days	5 years 6 months
Intrinsic value of options exercised			$ 100	$ 100
Arbutus Plans \| Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)			19,064,165	15,349,998
Options granted (in shares)			5,082,640
OnCore Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)			80,600
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation awards approved to be issued (in shares)			32,290,202
Number of options outstanding (in shares)			19,164,765
Number of additional shares authorized (in shares)			7,672,299
Stock Option \| 2016 and 2011 Plans \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life			10 years
Stock Option \| 2016 and 2011 Plans \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting period			4 years
Liability classified stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding (in shares)			20,000
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense			$ 0	$ 0
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)			7,672,299
Option vesting period			3 years
Unearned compensation expense			$ 1,900
Unearned compensation expense, recognition period				2 years 1 month 6 days

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 26,285	$ 30,776
Investments in marketable securities, current	99,718	116,137
Accounts receivable	1,776	1,352
Prepaid expenses and other current assets	4,248	2,874
Total current assets	132,027	151,139
Property and equipment, net of accumulated depreciation	4,674	5,070
Investments in marketable securities, non-current	6,284	37,363
Right of use asset	1,416	1,744
Other non-current assets	0	103
Total assets	144,401	195,419
Current liabilities:
Accounts payable and accrued liabilities	10,271	16,029
Deferred Revenue, Current	11,791	16,456
Lease liability, current	425	372
Total current liabilities	22,487	32,857
Liability related to sale of future royalties	6,953	10,365
Deferred Revenue, Noncurrent	0	5,999
Contingent consideration	7,600	7,531
Lease liability, non-current	1,343	1,815
Total liabilities	38,383	58,567
Stockholders’ equity
Common shares, Authorized: unlimited number without par value, Issued and outstanding: 144,987,736 (December 31, 2020: 89,678,722)	1,349,821	1,318,737
Additional paid-in capital	81,270	72,406
Deficit	(1,276,652)	(1,203,803)
Accumulated other comprehensive loss	(48,421)	(50,488)
Total stockholders' equity	106,018	136,852
Total liabilities and stockholders' equity	$ 144,401	$ 195,419

Cover - USD ($)	12 Months Ended
Cover - USD ($)	Dec. 31, 2023	Mar. 01, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-34949
Entity Registrant Name	Arbutus Biopharma Corp
Entity Incorporation, State or Country Code	A1
Entity Tax Identification Number	98-0597776
Entity Address, Address Line One	701 Veterans Circle
Entity Address, City or Town	Warminster
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18974
City Area Code	267
Local Phone Number	469-0914
Title of 12(b) Security	Common shares, without par value
Trading Symbol	ABUS
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 288,128,811
Entity Common Stock, Shares Outstanding		179,492,199
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant’s definitive proxy statement for its 2024 Annual Meeting of Shareholders, which the registrant intends to file pursuant to Regulation 14A with the Securities and Exchange Commission no later than 120 days after the registrant’s fiscal year ended December 31, 2023, are incorporated by reference into Part III of this Form 10-K.
Amendment Flag	false
Entity Central Index Key	0001447028
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Document Financial Statement Error Correction [Flag]	false

Significant accounting policies - Computation of basic and diluted net income (loss) per common share (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Weighted average number of common shares - basic (in shares)	165,960,379	150,939,337
Weighted average number of common shares - diluted (in shares)	165,960,379	150,939,337
Basic net loss attributable to common shareholders per share (in USD per share)	$ (0.44)	$ (0.46)
Diluted net loss attributable to common shareholders per share (in USD per share)	$ (0.44)	$ (0.46)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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-URI https://asc.fasb.org//1943274/2147480175/815-40-65-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-11

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-7

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-2

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 60B
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-60B

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 250
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483443/250-10-50-4

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482662/260-10-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(25))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(27))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(23))
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Reference 15: http://www.xbrl.org/2003/role/exampleRef
-Topic 260
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-Section 55
-Paragraph 52
-Publisher FASB
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482689/260-10-45-7

+ Details

Leases

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Leases

The Company had one operating lease for its office and laboratory space as of December 31, 2023. The Company’s corporate headquarters is located at 701 Veterans Circle, Warminster, Pennsylvania. The lease expires on April 30, 2027, and the Company has the option of extending the lease for two further five-year terms. The Company also previously leased office space located at 626 Jacksonville Road, Warminster, Pennsylvania under a lease that terminated on August 31, 2022.

The Company accounts for its leases under ASC 842, Leases. Leases with an initial term of 12 months or less are not recorded on the balance sheet. The Company determines if an arrangement is a lease at inception. Right-of-use assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease right-of-use assets and lease liabilities are recognized based on the present value of lease payments over the lease term. The leases do not provide an implicit rate so in determining the present

value of lease payments, the Company utilized its incremental borrowing rate for the applicable lease, which was 9.0% for the 701 Veterans Circle lease and 7.6% for the 626 Jacksonville Road lease. The Company recognizes lease expense on a straight-line basis over the remaining lease term.

During the years ended December 31, 2023 and 2022, the Company incurred total operating lease expenses of $0.6 million and $0.7 million, respectively, which included lease expenses associated with fixed lease payments of $0.5 million and $0.6 million, respectively, and variable payments associated with common area maintenance and similar expenses were $0.1 million in both years.

Weighted average remaining lease term and discount rate were as follows:


			As of December 31, 2023
Weighted-average remaining lease term (years)			3.3
Weighted average discount rate			9.0%

The Company did not include options to extend its lease terms as part of its ROU asset and lease liabilities.

Supplemental cash flow information related to the Company’s operating leases was as follows:


	2023		2022
	(in thousands)
Cash paid for amounts included in the measurement of lease liabilities	$	598	$	641

Future minimum lease payments under operating leases that have remaining terms as of December 31, 2023 are as follows:


	As of December 31, 2023
	(in thousands)
2024	$	616
2025	635
2026	654
2027	134
2028	—
Thereafter	—
Total lease payments	$	2,039
Less: interest	(271)
Present value of lease payments	$	1,768

Collaborations and royalty entitlements - Summary of revenues (Details) - USD ($) $ in Thousands	12 Months Ended		25 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 13, 2021
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total deferred revenue	$ 11,791		$ 11,791
Deferred Revenue, Current	11,791	$ 16,456	11,791
Deferred Revenue, Noncurrent	0	5,999	0
Total revenue	$ 18,141	39,019
Minimum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty interest, Percent interest	75.00%
Qilu Pharmaceutical Co, LTD.
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total deferred revenue	$ 11,800		11,800
Income Taxes Paid	4,400	4,400
Premiums Earned, Net	4,100
Recovery of Direct Costs			1,973
Contract with Customer, Liability, Revenue Recognized			36,681
Other Deferred Costs, Gross	600		600
Amortization of Other Deferred Charges	100
Revenue, Remaining Performance Obligation, Amount	13,764		$ 13,764	$ 50,445
Qilu Pharmaceutical Co, LTD. \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue	10,666	26,015
Qilu Pharmaceutical Co, LTD. \| One-Time Upfront Cash Payment
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Cash payment for collaborations	40,000
Onpattro - Cash Royalty [Member] \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue	3,608	5,316
Other Milestones and Royalty Payments [Member] \| License
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Total revenue	0	35
Barinthus
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Costs related to collaboration	1,800	800
Costs related to collaboration	1,800	$ 800
ONPATTRO, global net sales [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Annual Revenue Threshold	$ 500,000
OMERS \| Minimum
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Royalty interest, Percent interest	0.75%

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Schedule of lease cost

Weighted average remaining lease term and discount rate were as follows:


			As of December 31, 2023
Weighted-average remaining lease term (years)			3.3
Weighted average discount rate			9.0%

The Company did not include options to extend its lease terms as part of its ROU asset and lease liabilities.

Supplemental cash flow information related to the Company’s operating leases was as follows:


	2023		2022
	(in thousands)
Cash paid for amounts included in the measurement of lease liabilities	$	598	$	641

Schedule of lease maturity

Future minimum lease payments under operating leases that have remaining terms as of December 31, 2023 are as follows:


	As of December 31, 2023
	(in thousands)
2024	$	616
2025	635
2026	654
2027	134
2028	—
Thereafter	—
Total lease payments	$	2,039
Less: interest	(271)
Present value of lease payments	$	1,768

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
OPERATING ACTIVITIES
Net loss	$ (72,849)	$ (69,456)
Non-cash items:
Depreciation	1,404	1,427
Gain on sale of property and equipment	(20)	0
Stock-based compensation expense	9,301	7,182
Change in fair value of contingent consideration	69	2,233
Non-cash royalty revenue	(3,867)	(7,653)
Non-cash interest expense	455	1,722
Net accretion and amortization of investments in marketable securities	(2,196)	(54)
Net change in operating items:
Accounts receivable	(424)	(453)
Prepaid expenses and other assets	(943)	2,430
Accounts payable and accrued liabilities	(5,758)	5,216
Deferred license revenue	(10,664)	22,455
Other liabilities	(444)	(405)
Net cash used in operating activities	(85,936)	(35,356)
INVESTING ACTIVITIES
Purchase of investments in marketable securities	(80,509)	(130,430)
Disposition of investments in marketable securities	132,270	56,000
Proceeds from sale of property and equipment	20	0
Acquisition of property and equipment	(1,008)	(512)
Net cash provided by/(used in) investing activities	50,773	(74,942)
FINANCING ACTIVITIES
Issuance of common shares pursuant to Share Purchase Agreement	0	10,973
Issuance of common shares pursuant to the Open Market Sale Agreement	29,852	20,324
Issuance of common shares pursuant to exercise of stock options	260	122
Issuance of common shares pursuant to exercise of ESPP	535	395
Net cash provided by financing activities	30,647	31,814
Effect of foreign exchange rate changes on cash and cash equivalents	25	(22)
Decrease in cash and cash equivalents	(4,491)	(78,506)
Cash and cash equivalents, beginning of period	30,776	109,282
Cash and cash equivalents, end of period	$ 26,285	$ 30,776

Investment in Genevant	12 Months Ended
Investment in Genevant	Dec. 31, 2023
Equity Method Investments and Joint Ventures [Abstract]
Investment in Genevant	Investment in Genevant In April 2018, the Company entered into an agreement with Roivant Sciences Ltd. (Roivant), its largest shareholder, to launch Genevant Sciences Ltd. (Genevant), a company focused on a broad range of RNA-based therapeutics enabled by the Company’s LNP and ligand conjugate delivery technologies. The Company licensed rights to its LNP and ligand conjugate delivery platforms to Genevant for RNA-based applications outside of HBV, except to the extent certain rights had already been licensed to other third parties (the Genevant License). The Company retained all rights to its LNP and conjugate delivery platforms for HBV. Under the Genevant License, as amended, if a third party sublicensee of intellectual property licensed by Genevant from the Company commercializes a sublicensed product, the Company becomes entitled to receive a specified percentage of certain revenue that may be received by Genevant for such sublicense, including royalties, commercial milestones and other sales-related revenue, or, if less, tiered low single-digit royalties on net sales of the sublicensed product. The specified percentage is 20% in the case of a mere sublicense (i.e., naked sublicense) by Genevant without additional contribution and 14% in the case of a bona fide collaboration with Genevant. Additionally, if Genevant receives proceeds from an action for infringement by any third parties of the Company’s intellectual property licensed to Genevant, the Company would be entitled to receive, after deduction of litigation costs, 20% of the proceeds received by Genevant or, if less, tiered low single-digit royalties on net sales of the infringing product (inclusive of the proceeds from litigation or settlement, which would be treated as net sales). The Company accounts for its interest in Genevant as equity securities without readily determinable fair values. Accordingly, an estimate of the fair value of the securities is based on the original cost less previously recognized equity method losses, less impairments, plus or minus changes resulting from observable price changes in orderly transactions for identical or a similar Genevant securities. As of December 31, 2023, the carrying value of the Company’s investment in Genevant was zero and the Company owned approximately 16% of the common equity of Genevant.

Investments in marketable securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Investments in marketable securities

Investments in marketable securities and cash equivalents consisted of the following:


	Amortized Cost		Gross Unrealized Gain(1)		Gross Unrealized Loss(1)		Fair Value
As of December 31, 2023	(in thousands)
Cash equivalents
Money market fund	$	18,029	$	—	$	—	$	18,029
Total	$	18,029	$	—	$	—	$	18,029
Investments in marketable short-term securities
US government agency bonds	$	17,918	$	—	$	(44)	$	17,874
US corporate bonds	71,045		30		(189)		70,886
Yankee bonds	2,000		—		(17)		1,983
US government bonds	9,001		—		(26)		8,975
Total	$	99,964	$	30	$	(276)	$	99,718
Investments in marketable long-term securities

US corporate bonds	$	6,273	$	18	$	(7)	$	6,284

Total	$	6,273	$	18	$	(7)	$	6,284

(1) Gross unrealized gain (loss) is pre-tax and is reported in accumulated other comprehensive loss.


	Amortized Cost		Gross Unrealized Gain(1)		Gross Unrealized Loss(1)		Fair Value
As of December 31, 2022	(in thousands)
Cash equivalents
Money market fund	$	23,218	$	—	$	—	$	23,218
Total	$	23,218	$	—	$	—	$	23,218
Investments in marketable short-term securities
US government agency bonds	$	26,686	$	—	$	(424)	$	26,262
US corporate bonds	27,144		—		$	(303)	$	26,841
US treasury bills	8,483		—		$	(16)	8,467
US government bonds	55,361		—		(794)		54,567
Total	$	117,674	$	—	$	(1,537)	$	116,137
Investments in marketable long-term securities
US government agency bonds	$	3,724	$	—	$	(130)	$	3,594
US corporate bonds	25,433		—		(336)		25,097
US government bonds	8,972		—		(300)		8,672
Total	$	38,129	$	—	$	(766)	$	37,363

(1) Gross unrealized gain (loss) is pre-tax and is reported in accumulated other comprehensive loss.

Income taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Income taxes - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
Canadian federal and provincial income tax rate	27.00%	27.00%
Research and development credits	$ 7,300	$ 3,700
Scientific research and experimental development expenditures available for indefinite carry-forward	89,090	83,564
Deferred tax assets, operating loss carryforwards, subject to expiration	11,700	11,700
Pre-tax domestic losses	14,800	28,700
Pre-tax foreign losses	87,700	93,700
U.S. research and experimental expenditures capitalization	27,265	16,471
United States
Income Taxes [Line Items]
Net operating losses	230,200
Investment tax credit carryforward
Income Taxes [Line Items]
Investment tax credits available to reduce Canadian federal income taxes	7,100	7,200
Investment tax credits available to reduce provincial income taxes	2,000	2,000
Research tax credit carryforward
Income Taxes [Line Items]
Scientific research and experimental development expenditures available for indefinite carry-forward	61,900	62,200
Deferred tax assets, operating loss carryforwards, subject to expiration	$ 148,100	$ 148,100

Property and equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Cost	$ 16,574	$ 15,871
Accumulated depreciation	(11,900)	(10,801)
Net book value	4,674	5,070
Depreciation	1,404	1,427
Lab equipment
Property, Plant and Equipment [Line Items]
Cost	7,593	6,890
Accumulated depreciation	(5,892)	(5,679)
Net book value	1,701	1,211
Leasehold improvements
Property, Plant and Equipment [Line Items]
Cost	8,590	8,590
Accumulated depreciation	(5,618)	(4,749)
Net book value	2,972	3,841
Computer hardware and software
Property, Plant and Equipment [Line Items]
Cost	391	391
Accumulated depreciation	(390)	(373)
Net book value	$ 1	$ 18

Property and equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Schedule of property and equipment

The Company’s property and equipment balances as of the years ended December 31, 2023 and 2022 are as follows:


	Cost		Accumulated depreciation		Net book value
December 31, 2023	(in thousands)
Lab equipment	$	7,593	$	(5,892)	$	1,701
Leasehold improvements	8,590		(5,618)		2,972
Computer hardware and software	391		(390)		1
	$	16,574	$	(11,900)	$	4,674


	Cost		Accumulated depreciation		Net book value
December 31, 2022	(in thousands)
Lab equipment	$	6,890	$	(5,679)	$	1,211
Leasehold improvements	8,590		(4,749)		3,841
Computer hardware and software	391		(373)		18
	$	15,871	$	(10,801)	$	5,070

Stock-based compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Stock-based compensation

Awards outstanding and available for issuance

During the year ended December 31, 2023, the Company had stock options outstanding under the following plans (collectively, the Plans): the 2016 Omnibus Share and Incentive Plan (the 2016 Plan), the 2011 Omnibus Share Compensation Plan (the 2011 Plan); the 2023 and 2019 inducement grants; and the OnCore Option Plan. During the year ended December 31, 2023, the Company had restricted stock units outstanding under the 2016 Plan.

As of December 31, 2023, the aggregate number of shares authorized for awards under all Plans was 32,290,202. As of December 31, 2023, the Company had 19,164,765 options and 1,231,450 restricted stock units outstanding and 7,672,299 awards available for issuance under the Plans.

The Company issues new common shares of stock to settle options exercised.

The 2011 Plan expired in June 2021. Under the 2016 Plan, the Company’s board of directors may grant options, and other types of awards, to employees, directors and consultants of the Company. The exercise price of the options is determined by the Company’s board of directors but will be at least equal to the closing market price of the common shares on the date of grant and the term may not exceed 10 years. Options granted generally vest over four years for employees and for directors’ initial grants, and immediately for directors’ annual grants.

In June 2019, the Company provided an inducement grant of 1,112,000 options to its newly hired Chief Executive Officer. These options were awarded in a separate plan as non-qualified awards and are governed by the substantially the same terms as the 2016 Plan. In July 2023, the Company provided an inducement grant of 500,000 options to its newly hired General Counsel and Chief Compliance Officer and are governed by substantially the same terms as the 2016 Plan.

Hereafter, information on options governed by the 2016 Plan, the 2011 Plan and the 2023 and 2019 inducement grants (the Arbutus Plans) is presented on a consolidated basis as the terms of the plans are similar. Information on the OnCore Option Plan is presented separately.

Stock options under the Arbutus Plans

The following table summarizes activity related to the Company’s equity-classified stock options, including its performance options, for the year ended December 31, 2023:


	Stock Options Outstanding			Vested Stock Options	Non-Vested Stock Options
	Number	Weighted-Average Exercise Price		Number	Number	Weighted-Average Grant-Date Fair Value
Balance as of December 31, 2022	15,349,998	$	3.76	9,631,779	5,718,219	$	2.39
Options granted	5,082,640	$	2.78	—	5,082,640	$	2.15
Options exercised	(101,356)	$	2.56	(101,356)	—	$	—
Options forfeited, canceled or expired	(1,267,117)	$	4.39	(698,937)	(568,180)	$	2.24
Options vested	—	$	—	3,500,403	(3,500,403)	$	2.33
Balance as of December 31, 2023	19,064,165	$	3.47	12,331,889	6,732,276	$	2.25

The intrinsic value of options exercised under the Arbutus Plans during 2023 and 2022 are less than $0.1 million and $0.1 million, respectively.

The following table summarizes additional information related to the Company’s equity-classified stock options, including its performance options, as of December 31, 2023:


	As of December 31, 2023
Options outstanding and expected to vest
Number of stock options outstanding	19,064,165
Weighted-average exercise price	$	3.47
Intrinsic value (in $000s)	$	857
Weighted-average term remaining	7.0 years
Vested stock options
Number of vested stock options	12,331,889
Weighted-average exercise price	$	3.74
Intrinsic value (in $000s)	$	657
Weighted-average term remaining	6.2 years

The assumptions used in the Black-Scholes option-pricing for grants made during the years ended December 31, 2023 and 2022 are as follows:


	December 31, 2023		December 31, 2022
Expected average option term	5.6 years		5.5 years
Expected volatility	97.1	%	97.0	%
Expected dividends	—	%	—	%
Risk-free interest rate	3.57	%	1.77	%

The Company considers all available information when estimating the fair value of its stock option grants.

Stock options under the other plans

As of December 31, 2023, the Company also has 20,000 liability option awards outstanding with a weighted average exercise price of $12.10 and 80,600 stock option awards outstanding under the OnCore Option Plan with a weighted average exercise price of $0.56.

Restricted Stock Units under the Arbutus Plans

The following table summarizes activity related to the Company’s restricted stock units, for the year ended December 31, 2023:


	Restricted Stock Units Outstanding			Vested Restricted Stock Units	Non-Vested Restricted Stock Units
	Number	Weighted-Average Grant-Date Fair Value		Number	Number	Weighted-Average Grant-Date Fair Value
Balance as of December 31, 2022	—	$	—	—	—	$	—
Restricted stock units granted	1,344,550	$	2.90	—	1,344,550	$	2.90
Restricted stock units vested	—	$	—	—	—	$	—
Restricted stock units forfeited, canceled or expired	(113,100)	$	—	—	(113,100)	$	2.90
Restricted stock units vested	—	$	—	—	—	$	—
Balance as of December 31, 2023	1,231,450	$	2.90	—	1,231,450	$	2.90

The restricted stock units vest over three years in equal annual installments beginning one year from the grant date.

Employee Stock Purchase Plan

In May 2020, the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the ESPP) which became effective on May 28, 2020. A total of 1,500,000 common shares were reserved for issuance under the ESPP. Company employees contribute funds via payroll deductions, which are used to buy Company common shares at a discount of up to 15% based on the lower of the price at the start of the offering period and at the end of the relevant purchase period within such offering period. The initial offering period under the ESPP was September 1, 2020 through August 31, 2021 with purchase dates set on February 26, 2021 and August 31, 2021, with subsequent offering periods beginning on September 1 and ending on August 31. The Company issued 290,438 and 171,224 shares under its ESPP for the years ended December 31, 2023 and 2022, respectively. As of December 31, 2023, there were 842,001 shares remaining for issuance under the ESPP. For both of the years ended December 31, 2023 and 2022, the Company recognized $0.2 million of stock-based compensation expense related to the ESPP. The fair value of the right to acquire stock at a discounted price under the ESPP is calculated using the Black-Scholes valuation model and recorded as stock-based compensation. Expense is recognized over the period the employee contributes to the plan through payroll deductions.

Stock-based compensation expense

Total stock-based compensation expense was comprised of vesting of options and restricted stock units awarded to employees under the Arbutus and OnCore Plans calculated in accordance with the fair value method as described above and amortization of compensation cost related to the ESPP.

The Company recognizes forfeitures as they occur, and the effects of forfeitures are reflected in stock-based compensation expense.

Stock-based compensation has been recorded in the consolidated statement of operations and comprehensive loss as follows:


	Year Ended December 31,
	2023		2022
	(in thousands)
Research and development	$	3,684	$	2,912
General and administrative	5,617		4,270
Total	$	9,301	$	7,182

At December 31, 2023, there remained $10.6 million and $1.9 million of unrecognized compensation expense related to unvested equity employee stock options and restricted stock units, respectively, to be recognized as expense over a weighted-average periods of approximately 2.3 years and 2.1 years, respectively.

For each of the years ended December 31, 2023 and 2022, the Company had zero performance-based stock compensation expense.

Accounts payable and accrued liabilities (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Trade accounts payable		$ 3,223	$ 3,520
Payroll accruals		3,349	3,730
Research and development accruals		2,884	8,261
Professional fee accruals		815	512
Other accrued liabilities		0	6
Accounts payable and accrued liabilities		10,271	$ 16,029
Eliminated positions (as a percent)	24.00%
Restructuring Charges		1,100
Accrual payroll costs		$ 200

Sale of future royalties - Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Liability Related To Future Royalties [Roll Forward]
Net liability related to sale of future royalties - beginning balance	$ 10,365	$ 16,296
Non-cash royalty revenue	(3,867)	(7,653)
Non-cash interest expense	455	1,722
Net liability related to sale of future royalties - ending balance	6,953	$ 10,365
ONPATTRO, global net sales [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Annual Revenue Threshold	500,000
Annual Revenue Threshold	$ 500,000

Accounts payable and accrued liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Payables and Accruals [Abstract]

Schedule of accounts payable and accrued liabilities

Accounts payable and accrued liabilities are comprised of the following:


	December 31, 2023		December 31, 2022
	(in thousands)
Trade accounts payable	$	3,223	$	3,520
Payroll accruals	3,349		3,730
Research and development accruals	2,884		8,261
Professional fee accruals	815		512
Other accrued liabilities	—		6
Total	$	10,271	$	16,029

Fair value measurements - Changes in fair value of contingent consideration (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Liabilities Measured on Recurring Basis [Roll Forward]
Liability at beginning of the period	$ 7,531	$ 5,298
Increase in fair value of liability	69	2,233
Liability at end of the period	$ 7,600	$ 7,531

Sale of future royalties (Tables)

12 Months Ended

Dec. 31, 2023

Other Liabilities Disclosure [Abstract]

Activity related to net liability

The table below shows the activity related to the net liability for the years ended December 31, 2023 and December 31, 2022:


	Twelve Months Ended December 31,
	2023		2022
	(in thousands)
Net liability related to sale of future royalties - beginning balance	$	10,365	$	16,296
Non-cash royalty revenue	(3,867)		(7,653)
Non-cash interest expense	455		1,722
Net liability related to sale of future royalties - ending balance	$	6,953	$	10,365

Sale of future royalties - Narrative (Details) - USD ($)			12 Months Ended		42 Months Ended
	Jul. 02, 2019	Jan. 01, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2022
Other Liabilities Disclosure [Line Items]
Non-cash royalty revenue			$ 3,867,000	$ 7,653,000
Non-cash interest expense			$ 455,000	1,722,000
Minimum
Other Liabilities Disclosure [Line Items]
Royalty interest, Percent interest			75.00%
Maximum
Other Liabilities Disclosure [Line Items]
Royalty interest, Percent interest			112.50%
OMERS
Other Liabilities Disclosure [Line Items]
Royalty interest sold, percentage of sales, annual revenue threshold of highest tier	$ 500,000,000
Gross proceeds from royalty interest sold		$ 20,000,000
Royalty interest sold, maximum royalties for buyer	$ 30,000,000
Royalty guarantees commitments percentage	100.00%
Royalty payable	$ 30,000,000
Non-cash royalty revenue			$ 3,900,000	7,700,000	$ (22,700,000)
Transaction costs related to sale of future royalties	$ 1,500,000
Effective annual interest rate of royalty liability			2.10%
Non-cash interest expense			$ 500,000	$ 1,700,000
OMERS \| Minimum
Other Liabilities Disclosure [Line Items]
Royalty, percentage of interest sold	1.00%
Royalty interest, Percent interest			0.75%
OMERS \| Maximum
Other Liabilities Disclosure [Line Items]
Royalty, percentage of interest sold	2.33%
Royalty interest, Percent interest			1.125%

Fair value measurements - Assets and liabilities measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Liabilities
Contingent consideration	$ 7,600	$ 7,531	$ 5,298
Investments in marketable securities, non-current	6,284	37,363
Fair Value, Measurements, Recurring
Assets
Cash and cash equivalents	26,285	30,776
Investments in marketable securities, current	99,718	116,137
Total	132,287	184,276
Liabilities
Contingent consideration	7,600	7,531
Total	7,600	7,531
Investments in marketable securities, non-current	6,284	37,363
Fair Value, Measurements, Recurring \| Level 1
Assets
Cash and cash equivalents	26,285	30,776
Investments in marketable securities, current	0	0
Total	26,285	30,776
Liabilities
Contingent consideration	0	0
Total	0	0
Investments in marketable securities, non-current	0	0
Fair Value, Measurements, Recurring \| Level 2
Assets
Cash and cash equivalents	0	0
Investments in marketable securities, current	99,718	116,137
Total	106,002	153,500
Liabilities
Contingent consideration	0	0
Total	0	0
Investments in marketable securities, non-current	6,284	37,363
Fair Value, Measurements, Recurring \| Level 3
Assets
Cash and cash equivalents	0	0
Investments in marketable securities, current	0	0
Total	0	0
Liabilities
Contingent consideration	7,600	7,531
Total	7,600	7,531
Investments in marketable securities, non-current	$ 0	$ 0

Income taxes - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Components of Deferred Tax Assets [Line Items]
Operating loss carryforwards	$ 89,090	$ 83,564
Canadian research and development deductions	16,726	16,791
Book amortization in excess of tax	(451)	(461)
Revenue recognized for tax purposes in excess of revenue recognized for accounting purposes	1,878	2,799
Tax value in excess of accounting value in lease inducements	74	93
Equity method investment	3,375	3,375
U.S. Federal research and development credits	7,254	3,633
Deductible stock options	6,058	3,681
U.S. research and experimental expenditures capitalization	27,265	16,471
Deferred Tax Asset, Interest Carryforward	1,722	1,507
Deferred Tax Assets, Tax Deferred Expense, Other	322	387
Deferred revenue	114	153
Total deferred tax assets	163,711	145,287
Valuation allowance	(163,711)	(145,287)
Net deferred tax assets (liabilities)	0	0
Qilu Pharmaceutical Co, LTD.
Components of Deferred Tax Assets [Line Items]
Deferred revenue	3,184	6,063
Federal
Components of Deferred Tax Assets [Line Items]
Investment tax credits	5,147	5,278
Provincial
Components of Deferred Tax Assets [Line Items]
Investment tax credits	$ 1,953	$ 1,953