Kiniksa Pharmaceuticals (KNSA) 10-Q 4 Aug 22 2022 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2022	Jul. 31, 2022
Document information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2022
Entity File Number	001-38492
Entity Registrant Name	Kiniksa Pharmaceuticals, Ltd.
Entity Incorporation, State or Country Code	D0
Entity Tax Identification Number	98-1327726
Entity Address, Address Line One	Clarendon House
Entity Address, Address Line Two	2 Church Street
Entity Address, City or Town	Hamilton
Entity Address, Country	BM
Entity Address, Postal Zip Code	HM11
City Area Code	808
Local Phone Number	451-3453
Title of 12(b) Security	Class A Common Shares
Trading Symbol	KNSA
Security Exchange Name	NASDAQ
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
Entity Shell Company	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001730430
Amendment Flag	false
Common Shares
Document information
Entity Common Stock, Shares Outstanding		69,471,099
Class A common shares
Document information
Entity Common Stock, Shares Outstanding		34,470,421
Class B common shares
Document information
Entity Common Stock, Shares Outstanding		1,813,457
Class A1 common shares
Document information
Entity Common Stock, Shares Outstanding		17,129,603
Class B1 common shares
Document information
Entity Common Stock, Shares Outstanding		16,057,618

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 94,307	$ 122,470
Short-term investments	43,901	59,731
Accounts receivable, net	7,808	3,985
Inventory	19,916	3,675
Prepaid expenses and other current assets	14,006	6,585
Total current assets	179,938	196,446
Property and equipment, net	2,150	2,834
Operating lease right-of-use assets	4,069	5,550
Other long-term assets	5,669	8,720
Intangible asset, net	18,750	19,250
Total assets	210,576	232,800
Current liabilities:
Accounts payable	2,522	1,868
Accrued expenses	34,500	38,031
Operating lease liabilities	3,336	3,381
Other current liabilities	3,186	1,544
Total current liabilities	43,544	44,824
Non-current liabilities:
Non-current operating lease liabilities	1,278	2,669
Deferred revenue	12,000
Other long-term liabilities	260	270
Total liabilities	57,082	47,763
Commitments and contingencies (Note 14)
Shareholders' equity:
Additional paid-in capital	874,153	860,482
Accumulated other comprehensive income	(90)	(66)
Accumulated deficit	(720,588)	(675,397)
Total shareholders' equity	153,494	185,037
Total liabilities and shareholders' equity	210,576	232,800
Class A common shares
Shareholders' equity:
Common stock value	9	8
Class B common shares
Shareholders' equity:
Common stock value	1	1
Class A1 common shares
Shareholders' equity:
Common stock value	5	5
Class B1 common shares
Shareholders' equity:
Common stock value	$ 4	$ 4

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2022	Dec. 31, 2021
Class A common shares
Common stock, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Common stock, shares issued (in shares)	34,426,089	34,059,725
Common stock, shares outstanding (in shares)	34,426,089	34,059,725
Class B common shares
Common stock, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Common stock, shares issued (in shares)	1,813,457	1,813,457
Common stock, shares outstanding (in shares)	1,813,457	1,813,457
Class A1 common shares
Common stock, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Common stock, shares issued (in shares)	17,129,603	17,129,603
Common stock, shares outstanding (in shares)	17,129,603	17,129,603
Class B1 common shares
Common stock, par value (in dollars per share)	$ 0.000273235	$ 0.000273235
Common stock, shares issued (in shares)	16,057,618	16,057,618
Common stock, shares outstanding (in shares)	16,057,618	16,057,618

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue:
Product revenue, net	$ 26,972	$ 7,704	$ 59,161	$ 7,704
Costs and operating expenses:
Research and development	13,798	23,945	34,615	52,628
Selling, general and administrative	23,841	21,848	46,059	42,448
Total operating expenses	46,340	48,259	101,848	97,542
Loss from operations	(19,368)	(40,555)	(42,687)	(89,838)
Interest income	103	6	137	15
Loss before provision for income taxes	(19,265)	(40,549)	(42,550)	(89,823)
Provision for income taxes	(716)	(1,014)	(2,641)	(1,224)
Net loss	$ (19,981)	$ (41,563)	$ (45,191)	$ (91,047)
Net loss per share attributable to common shareholders-basic	$ (0.29)	$ (0.61)	$ (0.65)	$ (1.33)
Net loss per share attributable to common shareholders-diluted	$ (0.29)	$ (0.61)	$ (0.65)	$ (1.33)
Weighted average common shares outstanding-basic	69,289,972	68,395,703	69,213,860	68,332,943
Weighted average common shares outstanding-diluted	69,289,972	68,395,703	69,213,860	68,332,943
Comprehensive loss:
Net loss	$ (19,981)	$ (41,563)	$ (45,191)	$ (91,047)
Other comprehensive loss:
Unrealized gain (loss) on short-term investments and currency translation adjustments, net of tax	13	48	(24)	61
Total other comprehensive gain (loss)	13	48	(24)	61
Total comprehensive loss	(19,968)	(41,515)	(45,215)	(90,986)
Product revenue, net
Revenue:
Product revenue, net	26,972	7,704	49,161	7,704
Costs and operating expenses:
Cost of goods sold	5,029	$ 2,466	9,248	$ 2,466
Collaboration revenue
Revenue:
Product revenue, net			10,000
Costs and operating expenses:
Cost of goods sold	$ 3,672		$ 11,926

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Common Shares	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Total
Balance at the beginning of the period at Dec. 31, 2020	$ 18	$ 829,424	$ (34)	$ (517,473)	$ 311,935
Balance at the beginning of the period (in shares) at Dec. 31, 2020	68,215,022
Changes in equity
Issuance of Class A shares under incentive award plans and employee share purchase plan		1,106			1,106
Issuance of Class A shares under incentive award plans and employee share purchase plan (in shares)	115,012
Share-based compensation expense		7,126			7,126
Unrealized gain on short-term investments and currency translation adjustments			13		13
Net loss				(49,484)	(49,484)
Balance at the end of the period at Mar. 31, 2021	$ 18	837,656	(21)	(566,957)	270,696
Balance at the end of the period (in shares) at Mar. 31, 2021	68,330,034
Balance at the beginning of the period at Dec. 31, 2020	$ 18	829,424	(34)	(517,473)	311,935
Balance at the beginning of the period (in shares) at Dec. 31, 2020	68,215,022
Changes in equity
Unrealized gain on short-term investments and currency translation adjustments					61
Net loss					(91,047)
Balance at the end of the period at Jun. 30, 2021	$ 18	844,260	27	(608,520)	235,785
Balance at the end of the period (in shares) at Jun. 30, 2021	68,464,749
Balance at the beginning of the period at Mar. 31, 2021	$ 18	837,656	(21)	(566,957)	270,696
Balance at the beginning of the period (in shares) at Mar. 31, 2021	68,330,034
Changes in equity
Issuance of Class A shares under incentive award plans and employee share purchase plan		887			887
Issuance of Class A shares under incentive award plans and employee share purchase plan (in shares)	134,715
Share-based compensation expense		5,717			5,717
Unrealized gain on short-term investments and currency translation adjustments			48		48
Net loss				(41,563)	(41,563)
Balance at the end of the period at Jun. 30, 2021	$ 18	844,260	27	(608,520)	235,785
Balance at the end of the period (in shares) at Jun. 30, 2021	68,464,749
Balance at the beginning of the period at Dec. 31, 2021	$ 18	860,482	(66)	(675,397)	185,037
Balance at the beginning of the period (in shares) at Dec. 31, 2021	69,060,403
Changes in equity
Issuance of Class A shares under incentive award plans and employee share purchase plan	$ 1	422			423
Issuance of Class A shares under incentive award plans and employee share purchase plan (in shares)	210,720
Share-based compensation expense		6,031			6,031
Unrealized gain on short-term investments and currency translation adjustments			(37)		(37)
Net loss				(25,210)	(25,210)
Balance at the end of the period at Mar. 31, 2022	$ 19	866,935	(103)	(700,607)	166,244
Balance at the end of the period (in shares) at Mar. 31, 2022	69,271,123
Balance at the beginning of the period at Dec. 31, 2021	$ 18	860,482	(66)	(675,397)	185,037
Balance at the beginning of the period (in shares) at Dec. 31, 2021	69,060,403
Changes in equity
Unrealized gain on short-term investments and currency translation adjustments					(24)
Net loss					(45,191)
Balance at the end of the period at Jun. 30, 2022	$ 19	874,153	(90)	(720,588)	153,494
Balance at the end of the period (in shares) at Jun. 30, 2022	69,426,767
Balance at the beginning of the period at Mar. 31, 2022	$ 19	866,935	(103)	(700,607)	166,244
Balance at the beginning of the period (in shares) at Mar. 31, 2022	69,271,123
Changes in equity
Issuance of Class A shares under incentive award plans and employee share purchase plan		542			542
Issuance of Class A shares under incentive award plans and employee share purchase plan (in shares)	155,644
Share-based compensation expense		6,676			6,676
Unrealized gain on short-term investments and currency translation adjustments			13		13
Net loss				(19,981)	(19,981)
Balance at the end of the period at Jun. 30, 2022	$ 19	$ 874,153	$ (90)	$ (720,588)	$ 153,494
Balance at the end of the period (in shares) at Jun. 30, 2022	69,426,767

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (45,191)	$ (91,047)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,307	1,029
Share-based compensation expense	12,707	12,843
Non-cash lease expense	1,481	1,193
Amortization of premiums and accretion of discounts on short-term investments	240	603
Loss on disposal of property and equipment	34
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(7,421)	(196)
Accounts receivable, net	(3,823)	(2,551)
Inventory	(16,241)	(6,381)
Other long-term assets	2,918	(279)
Accounts payable	654	3,654
Accrued expenses and other liabilities	(1,889)	2,753
Operating lease liabilities	(1,436)	(863)
Deferred revenue	12,000
Other long-term liabilities	(10)	337
Net cash used in operating activities	(44,670)	(78,905)
Cash flows from investing activities:
Proceeds from sale of property and equipment	91
Purchases of property and equipment	(115)	(113)
Purchases of short-term investments	(55,734)	(97,460)
Proceeds from the maturities of short-term investments	71,300	248,400
Intangible asset acquired		(20,000)
Net cash provided by investing activities	15,542	130,827
Cash flows from financing activities:
Proceeds from issuance of Class A common shares under incentive award plans and employee share purchase plans	1,558	1,993
Payments in connection with Common Stock tendered for employee tax obligations	(593)
Net cash provided by financing activities	965	1,993
Net increase (decrease) in cash, cash equivalents and restricted cash	(28,163)	53,915
Cash, cash equivalents and restricted cash at beginning of period	122,470	114,248
Cash, cash equivalents and restricted cash at end of period	94,307	$ 168,163
Supplemental information:
Cash paid for income taxes	$ 3,293

Nature of the Business and Basi

Nature of the Business and Basis of Presentation	6 Months Ended
	Jun. 30, 2022
Nature of the Business and Basis of Presentation
Nature of the Business and Basis of Presentation	1. Nature of the Business and Basis of Presentation Kiniksa Pharmaceuticals, Ltd. (the “Company”) is a biopharmaceutical company focused on discovering, acquiring, developing and commercializing therapeutic medicines for patients suffering from debilitating diseases with significant unmet medical need. The Company’s portfolio of assets is based on strong biologic rationale or validated mechanisms, target underserved conditions and offer the potential for differentiation. The Company is subject to risks and uncertainties common to early, commercial stage companies in the biopharmaceutical industry and global health, societal, economic and market conditions, including adverse impact from the coronavirus disease 2019 (“COVID-19”) pandemic, the ongoing war in Ukraine, the Company’s dependence on third parties, including CROs and CMOs, the Company’s limited experience obtaining regulatory approvals, the potential failure of the Company to successfully complete research and development of its current or future product candidates, the potential inability of the Company to adequately protect its technology, potential competition, and the uncertainty that any current or future product candidates will obtain necessary government regulatory approval, that ARCALYST will continue to be commercially viable, and that any of the Company’s current or future product candidates, if approved, will be commercially viable. Such risks and uncertainties, especially those risks and uncertainties arising from the ongoing COVID-19 pandemic, may be subject to substantial and uncertain changes, which may cause significant disruption to the Company’s business and operations, preclinical studies and clinical trials, the business and operations of the third parties with whom the Company conducts business and the national and global economies, all of which may have material impacts on the Company’s business, financial condition and results of operations. Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries, Kiniksa Pharmaceuticals Corp. (“Kiniksa US”), Primatope Therapeutics, Inc. (“Primatope”) and Kiniksa Pharmaceuticals (UK), Ltd. (“Kiniksa UK”) as well as the subsidiaries of Kiniksa UK, Kiniksa Pharmaceuticals (Germany) GmbH (“Kiniksa Germany”), Kiniksa Pharmaceuticals (France) SARL (“Kiniksa France”), and Kiniksa Pharmaceuticals GmbH (“Kiniksa Switzerland”), after elimination of all significant intercompany accounts and transactions. Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the recognition of revenue, the capitalization of inventory, the accrual for research and development expenses and the valuation of share-based awards. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. Unaudited Interim Consolidated Financial Information The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information. The accompanying unaudited consolidated financial statements do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (the “2021 Form 10-K”). The Company’s accounting policies are described in the Notes to Consolidated Financial Statements in the Company’s 2021 Form 10-K and updated, as necessary, in this report. The accompanying year-end consolidated balance sheet was derived from audited financial statements but does not include all disclosures required by GAAP. The unaudited interim consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2022 and the results of its operations for the three and six months ended June 30, 2022 and 2021, the changes in its shareholders’ equity for the three and six months ended June 30, 2022 and 2021 and its cash flows for the six months ended June 30, 2022 and 2021. The results for the three and six months ended June 30, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods or any future year or period. Liquidity The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. As of June 30, 2022, the Company had an accumulated deficit of $720,588. During the six months ended June 30, 2022, the Company incurred a net loss of $45,191 and used $44,670 cash in operating activities. The Company expects to continue to generate operating losses and cash used in operations for the foreseeable future. As of June 30, 2022, the Company had cash, cash equivalents and short-term investments of $138,208. Based on its current operating plan, the Company expects that its cash, cash equivalents and short-term investments will be sufficient to fund its operations and capital expenditure requirements for at least twelve months from the issuance date of these consolidated financial statements. The future viability of the Company beyond that point is dependent on its ability to fund its operations through sales of ARCALYST and/or raise additional capital, as needed. If the Company is unable to grow sales of ARCALYST in future periods, the Company would need to seek additional financing through public or private securities offerings, debt financings, government funding or grants, or other sources, which may include licensing, collaborations or other strategic transactions or arrangements. Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its commercialization efforts, research and development programs for product candidates or product portfolio expansion, which could adversely affect its business prospects, or the Company may be unable to continue operations. ​ ​

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2022
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Revenue Recognition ​ ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”) outlines a five-step process for recognizing revenue from contracts with customers: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the separate performance obligations in the contract, and (v) recognize revenue associated with the performance obligations as they are satisfied. ​ The Company only applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. Once a contract is determined to be within the scope of ASC 606, the Company determines the performance obligations that are distinct. The Company recognizes as revenues the amount of the transaction price that is allocated to each respective performance obligation when the performance obligation is satisfied. Generally, the Company’s performance obligations are transferred to customers at a point in time, typically upon delivery of the product to the customer. ​ ASC 606 requires entities to record a contract asset when a performance obligation has been satisfied or partially satisfied, but the amount of consideration has not yet been received because the receipt of the consideration is conditioned on something other than the passage of time. ASC 606 also requires an entity to present a revenue contract as a contract liability in instances when a customer pays consideration, or an entity has a right to an amount of consideration that is unconditional (e.g., receivable), before the entity transfers a good or service to the customer. Collaboration Revenue The Company analyzes its collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (“Topic 808”). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of Topic 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of Topic 808 and which elements of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of Topic 606. For elements of collaboration arrangements that are accounted for pursuant to ASC 606, we identify the performance obligations and allocate the total consideration we expect to receive on a relative standalone selling price basis to each performance obligation. Variable consideration such as performance-based milestones will be included in the total consideration if we expect to receive such consideration and if it is probable that the inclusion of the variable consideration will not result in a significant reversal in the cumulative amount of revenue recognized under the arrangement. Our estimate of the total consideration we expect to receive under each collaboration arrangement is updated for each reporting period, and any adjustments to revenue are recorded on a cumulative catch-up basis. We exclude sales-based royalty and milestone payments from the total consideration we expect to receive until the underlying sales occur because the license to our intellectual property is deemed to be the predominant item to which the royalties or milestones relate as it is the primary driver of value in our collaboration arrangements. Key assumptions to determine the standalone selling price may include forecasted revenues, development timelines, reimbursement rates for personnel costs, discount rates and probabilities of technical and regulatory success. We recognize revenue associated with each performance obligation as the control over the promised goods or services transfer to our collaboration partner which occurs either at a point in time or over time. If control transfers over time, revenue is recognized by using a method of measuring progress that best depicts the transfer of goods or services. We evaluate the measure of progress and related inputs each reporting period and any resulting adjustments to revenue are recorded on a cumulative catch-up basis. Consideration received that does not meet the requirements to satisfy ASC 808 or ASC 606 revenue recognition criteria is recorded as deferred revenue in the accompanying consolidated balance sheets, classified as either short-term (less than 12 months) or long-term (more than 12 months) deferred revenue based on our best estimate of when such revenue will be recognized. There have been no other material changes to the significant accounting policies previously disclosed in the Company’s 2021 Form 10-K. Recently Adopted Accounting Pronouncements ​ ​

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	6 Months Ended
	Jun. 30, 2022
Fair Value of Financial Assets and Liabilities
Fair Value of Financial Assets and Liabilities	3. Fair Value of Financial Assets and Liabilities Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ● Level 1—Quoted prices in active markets for identical assets or liabilities. ● Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ● Level 3—Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The following tables present information about the Company’s financial instruments measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of June 30, 2022 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents — money market funds ​ $ 33,238 ​ $ — ​ $ — ​ $ 33,238 Cash equivalents — U.S. Treasury notes ​ ​ — ​ ​ 6,997 ​ ​ — ​ ​ 6,997 Short-term investments — U.S. Treasury notes ​ ​ — ​ ​ 43,901 ​ ​ — ​ ​ 43,901 ​ ​ $ 33,238 ​ $ 50,898 ​ $ — ​ $ 84,136 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of December 31, 2021 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents — money market funds ​ $ 94,324 ​ $ — ​ $ — ​ $ 94,324 Short-term investments — U.S. Treasury notes ​ ​ — ​ ​ 59,731 ​ ​ — ​ ​ 59,731 ​ ​ $ 94,324 ​ $ 59,731 ​ $ — ​ $ 154,055 ​ During the six months ended June 30, 2022 and the year ended December 31, 2021 there were no transfers between Level 1, Level 2 and Level 3. The money market funds were valued using quoted prices in active markets, which represent a Level 1 measurement in the fair value hierarchy. The Company’s cash equivalents and short-term investments as of June 30, 2022 and December 31, 2021 included U.S. Treasury notes, which are not traded on a daily basis and, therefore, represent a Level 2 measurement in the fair value hierarchy at each period end. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Credit ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Losses ​ Value June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash Equivalents - U.S. Treasury notes ​ $ 6,998 ​ $ — ​ $ (1) ​ $ — ​ $ 6,997 Short-term investments — U.S. Treasury notes ​ ​ 43,939 ​ ​ — ​ ​ (38) ​ ​ — ​ ​ 43,901 ​ ​ $ 50,937 ​ $ — ​ $ (39) ​ $ — ​ $ 50,898 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Credit ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Losses ​ Value December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments — U.S. Treasury notes ​ $ 59,745 ​ $ 1 ​ $ (15) ​ $ — ​ $ 59,731 ​ ​ $ 59,745 ​ $ 1 ​ $ (15) ​ $ — ​ $ 59,731 ​ As of June 30, 2022, the Company held 14 securities that were in an unrealized loss position. The aggregate fair value of securities held by the Company in an unrealized loss position was $43,901 at June 30, 2022. As of December 31, 2021, the Company held 11 securities that were in an unrealized loss position. The aggregate fair value of securities held by the Company in an unrealized loss position was $49,739 at December 31, 2021. As of June 30, 2022 and December 31, 2021, these securities were held by the Company in an unrealized loss position for less than 12 months. The Company determined that there was no material change in the credit risk of these securities. As a result, the Company determined it did not hold any investments with an other-than-temporary impairment as of June 30, 2022 and December 31, 2021.

Product Revenue, Net

Product Revenue, Net	6 Months Ended
	Jun. 30, 2022
Product Revenue, Net
Product Revenue, Net	4. Product Revenue, Net ARCALYST ​ Following the approval by the U.S. Food and Drug Administration (“FDA”) of ARCALYST on March 18, 2021, the Company began generating product revenue from sales of ARCALYST in April 2021. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ ​ 2022 ​ 2021 ​ 2022 ​ 2021 Product revenue, net ​ $ 26,972 ​ $ 7,704 ​ $ 49,161 ​ $ 7,704 ​ The following table summarizes balances and activity in each of the product revenue allowance and reserve categories for the six months ended June 30, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contractual ​ Government ​ ​ ​ ​ ​ ​ Adjustments ​ Rebates ​ Returns ​ Total Balance at December 31, 2021 ​ $ 515 ​ $ 719 ​ $ 101 ​ $ 1,335 Current provisions relating to sales in the current year ​ ​ 3,303 ​ ​ 1,621 ​ ​ 135 ​ ​ 5,059 Payments/returns relating to sales in the current year ​ ​ (2,255) ​ ​ (448) ​ ​ — ​ ​ (2,703) Payments/returns relating to sales in the prior years ​ ​ (301) ​ ​ (621) ​ ​ — ​ ​ (922) Balance at June 30, 2022 ​ $ 1,262 ​ $ 1,271 ​ $ 236 ​ $ 2,769 ​ ​ Total revenue-related reserves as of June 30, 2022 and December 31, 2021, included in our consolidated balance sheets, are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ ​ 2022 ​ 2021 Reduction of accounts receivable ​ $ (130) ​ $ (50) Components of other current liabilities ​ ​ 2,899 ​ ​ 1385 Total revenue-related reserves ​ $ 2,769 ​ $ 1,335 ​ Accounts receivable, net as of June 30, 2022 and December 31, 2021 related to product revenue was $7,632 and $3,910, respectively.

Inventory

Inventory	6 Months Ended
	Jun. 30, 2022
Inventory
Inventory	5. Inventory Inventory consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Raw materials ​ $ — ​ $ — Work-in-process ​ — ​ — Finished Goods ​ ​ 19,916 ​ ​ 3,675 ​ ​ $ 19,916 ​ $ 3,675 ​

Property and Equipment, Net

Property and Equipment, Net	6 Months Ended
	Jun. 30, 2022
Property and Equipment, Net
Property and Equipment, Net	6. Property and Equipment, Net Property and equipment, net consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Furniture, fixtures and vehicles ​ $ 225 ​ $ 62 Computer hardware and software ​ 345 ​ 341 Leasehold improvements ​ ​ 3,931 ​ ​ 3,931 Lab equipment ​ ​ 4,068 ​ ​ 4,249 Construction in progress ​ 10 ​ 166 Total property and equipment ​ ​ 8,579 ​ ​ 8,749 Less: Accumulated depreciation ​ (6,429) ​ (5,915) Total property and equipment, net ​ $ 2,150 ​ $ 2,834 ​ Depreciation expense was $350 and $416 during the three months ended June 30, 2022 and 2021, respectively, and $709 and $706 during the six months ended June 30, 2022 and 2021, respectively. ​

Intangible Assets

Intangible Assets	6 Months Ended
	Jun. 30, 2022
Intangible Assets
Intangible Assets	7. Intangible Assets Intangible assets, net of accumulated amortization, impairment charges and adjustments as of June 30, 2022 and December 31, 2021 are summarized in the following table. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, 2022 ​ As of December 31, 2021 ​ ​ Estimated ​ ​ ​ Accumulated ​ ​ ​ ​ ​ Accumulated ​ ​ ​ life Cost Amortization Net ​ Cost Amortization Net Regulatory milestone ​ 20 years ​ $ 20,000 ​ $ 1,250 ​ $ 18,750 ​ $ 20,000 ​ $ 750 ​ $ 19,250 ​ ​ ​ ​ $ 20,000 ​ $ 1,250 ​ $ 18,750 ​ $ 20,000 ​ $ 750 ​ $ 19,250 ​

Accrued Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2022
Accrued Expenses
Accrued Expenses	8. Accrued Expenses Accrued expenses consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Accrued research and development expenses ​ $ 14,374 ​ $ 24,977 Accrued employee compensation and benefits ​ ​ 7,410 ​ ​ 8,916 Accrued collaboration expenses ​ ​ 9,612 ​ ​ 835 Accrued legal, commercial and professional fees ​ 2,734 ​ 2,933 Other ​ 370 ​ 370 ​ ​ $ 34,500 ​ $ 38,031 ​

Share-Based Compensation

Share-Based Compensation	6 Months Ended
	Jun. 30, 2022
Share-Based Compensation
Share-Based Compensation	9. Share-Based Compensation The Company maintains several equity compensation plans, including the 2018 Incentive Award Plan (the “2018 Plan”), 2018 Employee Share Purchase Plan (the “2018 ESPP”), and Rilonacept Long-Term Incentive Plan (“RLTIP”) which was approved under the 2018 Plan. Upon the effectiveness of the 2018 Plan, the Company ceased granting awards under its 2015 Equity Incentive Plan (as amended, the “2015 Plan” and together with the 2018 Plan, the “Plans”). 2015 Plan As of June 30, 2022, there were 2,050,155 Class A common shares subject to outstanding awards under the 2015 Plan and reserved for issuance thereunder pursuant to such awards. 2018 Plan In May 2018, the Company’s board of directors and shareholders approved the 2018 Plan, which became effective on May 23, 2018. The 2018 Plan provides for the grant of incentive share options, nonqualified share options, share appreciation rights, restricted shares, dividend equivalents, restricted share units (“RSUs”) and other share- or cash- based awards. As of June 30, 2022, 2,659,928 shares remained available for future grant under the 2018 Plan. 2018 ESPP In December 2021, pursuant to the 2018 ESPP’s evergreen provision, the Company’s board of directors approved an increase in the number of shares available for future issuance under the 2018 ESPP, as of January 1, 2022, of 90,000 shares. As of June 30, 2022, 644,801 Class A common shares were available for future issuance under the 2018 ESPP. Options Share option activity under the Plans is summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average ​ ​ Shares ​ Exercise Price Outstanding as of December 31, 2021 9,226,846 ​ $ 14.14 Granted 1,561,160 ​ $ 10.74 Exercised (207,972) ​ $ 5.45 Forfeited (1,006,491) ​ $ 15.60 Outstanding as of June 30, 2022 9,573,543 ​ $ 13.62 Share options exercisable as of June 30, 2022 5,246,401 ​ $ 13.54 Share options unvested as of June 30, 2022 4,327,142 ​ $ 13.72 ​ As of June 30, 2022, total unrecognized compensation expense related to the unvested share option awards was $37,588 which is expected to be recognized over a weighted average remaining period of 2.53 years. ​ Restricted Share Units ​ Beginning in March 2021, the Company began granting RSUs with service conditions (“Time-Based RSUs”) to eligible employees as part of its equity incentive compensation. The Time-Based RSUs vest 25% on each of the first, second, third and fourth anniversaries of the date of grant, subject to continued employment through such dates. During the years ended December 31, 2020 and 2019, the Company granted the first RSU awards (“First RLTIP RSU Awards”) as part of the RLTIP to eligible employees. During the year ended December 31, 2021, the FDA Milestone (as defined in RLTIP) was achieved (the date of such achievement, the “Achievement Date”) and (1) the number of Class A common shares issuable under the First RLTIP RSU Awards were determined in accordance with the RLTIP and vested in one installment on the first anniversary of the Achievement Date, subject to continued employment through such date, and (2) the Company granted a second set of RSU awards to eligible employees on the Achievement Date with respect to a number of shares determined in accordance with the RLTIP, which will vest on the second anniversary of the Achievement Date, subject to continued employment through such date. During the three months ended June 30, 2022 and 2021, the Company recognized compensation expense of $932 and $526, respectively, related to RSUs including those granted in connection with the RLTIP. During the six months ended June 30, 2022 and 2021, the Company recognized compensation expense of $1,551 and $2,030, respectively, related to RSUs including those granted in connection with the RLTIP. ​ The following table summarizes RSU activity, including the RSUs outstanding under the RLTIP for the six months ended June 30, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ Number of ​ Grant Date ​ ​ Shares ​ Fair Value Unvested RSUs as of December 31, 2021 ​ 885,021 ​ $ 15.72 Granted ​ 655,099 ​ $ 10.71 Vested ​ (170,254) ​ $ 15.79 Forfeited ​ (211,122) ​ $ 14.08 Unvested RSUs as of June 30, 2022 ​ 1,158,744 ​ $ 13.17 As of June 30, 2022, total unrecognized compensation cost related to the RSU awards was $12,743 which is expected to be recognized over a weighted average remaining period of 3.24 years. Share-Based Compensation Share-based compensation expense was classified in the consolidated statements of operations and comprehensive loss as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ 2022 2021 ​ 2022 2021 Cost of goods sold ​ $ 112 ​ $ 39 ​ $ 292 ​ $ 39 Research and development expenses ​ ​ 1,608 ​ ​ 1,923 ​ ​ 3,584 ​ ​ 4,557 Selling, general and administrative expenses ​ 4,956 ​ 3,755 ​ 8,831 ​ 8,247 ​ ​ $ 6,676 ​ $ 5,717 ​ $ 12,707 ​ $ 12,843 ​

Out-Licensing Agreements

Out-Licensing Agreements	6 Months Ended
	Jun. 30, 2022
Out-licensing Agreements
Out-licensing Agreements	10. Huadong Collaboration Agreements On February 21, 2022 (the “Effective Date”), the Company entered into two collaboration and license agreements (each, a “Collaboration Agreement” and together, the “Collaboration Agreements”) with Hangzhou Zhongmei Huadong Pharmaceutical Co., Ltd. (“Huadong”), pursuant to which the Company granted Huadong exclusive rights to develop and commercialize rilonacept and develop, manufacture and commercialize mavrilimumab (each, a “Licensed Product” and together, the “Licensed Products”) in the following countries: People’s Republic of China, Hong Kong SAR, Macao SAR, Taiwan Region, South Korea, Indonesia, Singapore, The Philippines, Thailand, Australia, Bangladesh, Bhutan, Brunei, Burma, Cambodia, India, Laos, Malaysia, Maldives, Mongolia, Nepal, New Zealand, Sri Lanka, and Vietnam (collectively, the “Territory”). Under the Collaboration Agreements, the Company received a total upfront cash payment of $22,000, which includes $12,000 for the Territory license of rilonacept and $10,000 for the Territory license of mavrilimumab. The Company will be eligible to receive up to approximately $70,000 in payments for rilonacept, and up to approximately $576,000 in payments for mavrilimumab, including specified development, regulatory and sales-based milestones. Huadong will also be obligated to pay the Company tiered percentage royalties on a Licensed Product-by-Licensed Product basis ranging from the low-teens to low-twenties on annual net sales of each Licensed Product in the Territory, subject to certain reductions tied to rilonacept manufacturing costs and certain other customary reductions, with an aggregate minimum floor. Royalties will be payable on a Licensed Product-by-Licensed Product and country-by-country or region-by-region basis until the later of (i) 12 years after the first commercial sale of the applicable Licensed Product in such country or region in the Territory, (ii) the date of expiration of the last valid patent claim of the Company’s patent rights or any joint collaboration patent rights that covers the applicable Licensed Product in such country or region in the Territory, and (iii) the expiration of the last regulatory exclusivity for the applicable Licensed Product in such country or region in the Territory. Pursuant and subject to the terms of the Collaboration Agreements, Huadong has the exclusive right to conduct Territory-specific development activities for the Licensed Products in the Territory, the first right to support global development of the Licensed Products by serving as the sponsor of the global clinical trials conducted in the Territory and the exclusive right to commercialize the Licensed Products in the Territory. Huadong will be responsible for all costs of development activities and commercialization in the Territory. Both the Company and Huadong participate in a Joint Steering Committee (“JSC”), which coordinates and oversees the exploitation of the Licensed Products in the Territory. The Company will supply certain materials to support development and commercialization activities for both mavrilimumab and rilonacept. Under the Collaboration Agreement for mavrilimumab, Huadong has the right to assume manufacturing responsibilities for materials in the Territory. Under the Collaboration Agreement for rilonacept, Huadong does not have rights to perform manufacturing activities in the Territory. Absent early termination, each Collaboration Agreement will continue on a country-by-country or region-by-region basis until there are no more royalty payments owed to the Company in such country or region for the applicable Licensed Product. Huadong has the right to terminate each Collaboration Agreement at its discretion upon 12 months’ notice and either party may terminate the applicable Collaboration Agreement in the event of an uncured material breach of the other party or in the case of insolvency of the other party. In addition, the Company may terminate the applicable Collaboration Agreement if Huadong or its affiliates or sublicensees challenges the scope, validity, or enforceability of the Company’s patent rights being licensed to Huadong. If Huadong and its affiliates do not conduct any material development or commercialization activities with respect to a Licensed Product in the People’s Republic of China for a continuous period of longer than six months, then, subject to certain exceptions, the Company may terminate the Collaboration Agreement applicable to such Licensed Product with 60 days’ prior written notice. In addition, Huadong’s rights under each Collaboration Agreement in certain regions within the Territory may be subject to termination upon failure by Huadong to perform certain clinical, development or commercialization activities, as applicable, with respect to the applicable Licensed Product in such regions. The Company concluded that Huadong is a customer in these Collaboration Agreements, and as such, each Collaboration Agreement falls within the scope of the revenue recognition guidance in ASC 606. The Company concluded that the Collaboration Agreements should not be combined and treated as a single arrangement for accounting purposes as the Collaboration Agreements were negotiated separately with separate and distinct commercial objectives, the amount of consideration in one Collaboration Agreement is not dependent on the price or performance of the other Collaboration Agreement, and the goods and services promised in the Collaboration Agreements are not a single performance obligation. Accounting for Mavrilimumab Collaboration Agreement As of the Effective Date, the Company identified the following material promises in the mavrilimumab Collaboration Agreement that were evaluated under the scope of ASC 606: delivery of (i) exclusive license for mavrilimumab in the Territory and (ii) clinical manufacturing supply of certain materials for mavrilimumab products in the Territory. The Company also evaluated whether certain options outlined within the mavrilimumab Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options convey a material right to Huadong and therefore are not considered separate performance obligations within the mavrilimumab Collaboration Agreement. The Company assessed the above promises and determined that the exclusive license for mavrilimumab in the Territory is reflective of a vendor-customer relationship and therefore represents a performance obligation within the scope of ASC 606. The exclusive license for mavrilimumab in the Territory is considered functional intellectual property and distinct from other promises under the Collaboration Agreement as Huadong can benefit from the license on its own or together with other readily available resources and the license is separately identifiable from the other promises. The clinical manufacturing supply of certain materials for mavrilimumab products in the Territory is considered distinct from the exclusive license for mavrilimumab as Huadong can benefit from the manufacturing services together with the license transferred by the Company at the inception of the Collaboration Agreement. Therefore, each represents a separate performance obligation within a contract with a customer under the scope of ASC 606 at contract inception. The Company determined the transaction price under ASC 606 at the inception of the mavrilimumab Collaboration Agreement which includes $10,000, consisting of the upfront payment. The Company also includes an estimate of variable consideration associated with the clinical manufacturing supply of certain materials when those materials are shipped. The Company determined that any variable consideration related to development and regulatory milestones is deemed fully constrained and therefore excluded from the transaction price due to the high degree of uncertainty and risk associated with these potential payments, as the Company determined that it could not assert that it was probable that a significant reversal in the amount of cumulative revenue recognized will not occur. The Company also determined that royalties and sales milestones relate solely to the licenses of intellectual property. Revenue related to these royalties and sales milestones will only be recognized when the associated sales occur, and relevant thresholds are met, under the sales or usage-based royalty exception of Topic 606. As noted above, the Company identified two performance obligations in the mavrilimumab Collaboration Agreement: (i) the delivery of the exclusive license for mavrilimumab in the Territory; and (ii) the clinical manufacturing supply of certain materials for mavrilimumab products in the Territory. The selling price of each performance obligation in the mavrilimumab Collaboration Agreement was determined based on the Company’s standalone selling price (“SSP”) with the objective of determining the price at which it would sell such an item if it were to be sold regularly on a standalone basis. The Company allocated the variable consideration related to the manufacturing obligations to the future clinical supply of mavrilimumab products in the Territory and the remaining fixed and variable consideration to the license obligation. The Company recognizes revenue for the license performance obligations at a point in time, that is upon transfer of the license to Huadong. As control of the license was transferred on the Effective Date and Huadong could begin to use and benefit from the license, the Company recognized $10,000 of collaboration revenue during the six months ended June 30, 2022 under the mavrilimumab Collaboration Agreement. The Company will recognize revenue for the clinical manufacturing supply obligations at a point in time, that is upon each delivery of the supply to Huadong. ​ Accounting for Rilonacept Collaboration Agreement As of the Effective Date, the Company identified the following material promises in the rilonacept Collaboration Agreement that were evaluated under the scope of ASC 606: delivery of (i) exclusive license for rilonacept in the Territory; (ii) clinical manufacturing supply of certain materials for rilonacept products in the Territory; and (iii) commercial manufacturing supply of certain material for rilonacept products in the Territory. The Company also evaluated whether certain options outlined within the rilonacept Collaboration Agreement represented material rights that would give rise to a performance obligation and concluded that none of the options convey a material right to Huadong and therefore are not considered separate performance obligations within the rilonacept Collaboration Agreement. The Company assessed the above promises and determined that there is one combined performance obligation for the exclusive license for rilonacept and clinical and commercial manufacturing obligations for rilonacept products in the Territory. Huadong cannot exploit the value of the exclusive license for rilonacept products in the Territory without receipt of supply as the exclusive license for rilonacept products in the Territory does not convey to Huadong the right to manufacture and therefore the Company has combined the exclusive license for rilonacept products in the Territory and the manufacturing obligations into one performance obligation. ​ The Company determined the transaction price under ASC 606 at the inception of the rilonacept Collaboration Agreement which includes $12,000, consisting of the upfront payment. The Company also includes an estimate of variable consideration associated with the clinical manufacturing supply of certain materials when those materials are shipped. The Company determined that any variable consideration related to development and regulatory milestones, sales milestones and royalties are deemed fully constrained and therefore excluded from the transaction price due to the high degree of uncertainty and risk associated with these potential payments, as the Company determined that it could not assert that it was probable that a significant reversal in the amount of cumulative revenue recognized will not occur. Royalties and sales milestones will be recognized as the Company delivers the commercial manufactured product to Huadong. Any changes in estimates may result in a cumulative catch-up based on the number of units of manufactured product delivered. ​ As noted above, the Company identified a single combined performance obligation in the rilonacept Collaboration Agreement consisting of the exclusive license for rilonacept and clinical and commercial manufacturing obligations for rilonacept products in the Territory. The Company recognizes revenue for the combined performance obligation consisting of the exclusive license for rilonacept and clinical and commercial manufacturing obligations for rilonacept products in the Territory at a point in time, upon which control of materials are transferred to Huadong for each delivery of the associated materials. The Company currently expects to recognize the revenue over the life of the agreement. This estimate considers the timing of development and commercial activities under the rilonacept License Agreement and may be reduced or increased based on changes in the various activities. ​ The Company has not recognized any revenue under the rilonacept License Agreement for the three months and six months ended June 30, 2022 as there has been no delivery of materials under the rilonacept License Agreement to date. The full transaction price of $12,000 is recorded in long-term deferred revenue, based upon timing of anticipated future shipments. ​ The following table summarizes deferred revenue in connection with collaboration agreements for the six months ended June 30, 2022: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at ​ ​ ​ ​ ​ ​ Balance at End ​ ​ Beginning of Period ​ Additions ​ Deductions ​ of Period Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Huadong rilonacept ​ $ — ​ $ 12,000 ​ $ — ​ $ 12,000 Deferred revenue ​ $ — ​ $ 12,000 ​ $ — ​ $ 12,000 ​

In-license, Acquisition and Col

In-license, Acquisition and Collaboration Agreements	6 Months Ended
	Jun. 30, 2022
License, Acquisition and Collaboration Agreements
In-license, Acquisition and Collaboration Agreements	11. In-license, Acquisition and Collaboration Agreements Biogen Asset Purchase Agreement In September 2016, the Company entered into an asset purchase agreement (the “Biogen Agreement”) with Biogen MA Inc. (“Biogen”) to acquire all of Biogen’s right, title and interest in and to certain assets used in or relating to vixarelimab and other antibodies covered by certain patent rights, including patents and other intellectual property rights, clinical data, know-how, and clinical drug supply. In addition, Biogen granted to the Company a non-exclusive, sublicensable, worldwide license to certain background patent rights related to the vixarelimab program. The Company is obligated to use commercially reasonable efforts to develop and commercialize such acquired products. Under the Biogen Agreement, the Company is obligated to make milestone payments to Biogen of up to $179,000 upon the achievement of specified clinical and regulatory milestones in multiple indications in various territories, of which $165,000 remains as of June 30, 2022. Additionally, the Company could be obligated to make up to an aggregate of up to $150,000 of payments upon the achievement of specified annual net sales milestones and to pay tiered royalties on escalating tiers of annual net sales of licensed products starting in the high single-digit percentages and ending below the teens. The Company also agreed to pay certain obligations under third-party contracts retained by Biogen that relate to the vixarelimab program. Under these retained contracts, the Company paid a one-time upfront sublicense fee and is obligated to pay insignificant annual maintenance fees as well as clinical and regulatory milestone payments of up to an aggregate of $1,575. The Biogen Agreement will terminate upon the expiration of all payment obligations with respect to the last product in all countries in the territory. The Company has the right to terminate the agreement with 90 days’ prior written notice. Both parties may terminate by mutual written consent or in the event of material breach of the agreement by the other party that remains uncured for 90 days (or 30 days for payment-related breaches). During the three and six months ended June 30, 2022, the Company recorded research and development expense of $34, related to the annual maintenance in connection with the Biogen Agreement. During the three and six months ended June 30, 2021, the Company recorded research and development expense of $14 and $28 respectively, related to the annual maintenance fee in connection with the retained contracts. Beth Israel Deaconess Medical Center License Agreement In 2019, the Company exercised the call option under the stock purchase option agreement with Primatope and acquired all of the outstanding securities of Primatope (the “Primatope Acquisition”). As a result of the Primatope Acquisition, the Company acquired the rights to an exclusive license to certain intellectual property rights controlled by Beth Israel Deaconess Medical Center, Inc. (“BIDMC”) to make, use, develop and commercialize KPL-404 (the “BIDMC Agreement”). Under the BIDMC Agreement, the Company is solely responsible for all development, regulatory and commercial activities and costs. The Company is also responsible for costs related to filing, prosecuting and maintaining the licensed patent rights. Under the BIDMC Agreement, the Company is obligated to pay an insignificant annual maintenance fee as well as clinical and regulatory milestone payments of up to an aggregate of $1,200 to BIDMC. The Company is also obligated to pay a low single-digit royalty on annual net sales of products licensed under the agreement. During the three and six months ended June 30, 2022 and 2021, the Company did not record any research and development expense in connection with the BIDMC Agreement. Regeneron License Agreement In September 2017, the Company entered into a license agreement (the “Regeneron Agreement”) with Regeneron Pharmaceuticals, Inc. (“Regeneron”), pursuant to which the Company has been granted an exclusive license under certain intellectual property rights controlled by Regeneron to develop and commercialize ARCALYST worldwide, excluding the Middle East and North Africa, for all indications other than those in oncology and local administration to the eye or ear. Upon receiving positive data in RHAPSODY, the Company’s pivotal Phase 3 clinical trial of ARCALYST, Regeneron transferred the biologics license application, for ARCALYST to the Company. In March 2021, when the FDA granted approval of ARCALYST for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and children 12 years and older, the Company assumed the sales and distribution of ARCALYST for Cryopyrin-Associated Periodic Syndromes and Deficiency of Interleukin-1 Receptor Antagonist in the United States. ​ The Company made a $20,000 payment in the first quarter of 2021 in connection with the achievement of a specified regulatory milestone event. The $20,000 milestone was accounted for as an intangible asset and will be amortized over the life of the underlying asset. Related amortization expense will be recorded as cost of goods sold in the Company’s consolidated statement of operations and comprehensive loss. The Company evenly splits profits on sales of ARCALYST with Regeneron, where profits are determined after deducting from net sales of ARCALYST certain costs related to the manufacturing and commercialization of ARCALYST. Such costs include but are not limited to (i) the Company’s cost of goods sold for product used, sold or otherwise distributed for patient use by the Company; (ii) customary commercialization expenses, including the cost of the Company’s field force, and (iii) the Company’s cost to market, advertise and otherwise promote ARCALYST, with such costs identified in subsection (iii) subject to specified limits.  In addition, should there be a transfer of technology related to the manufacture of ARCALYST, then, to the extent permitted in accordance with the Regeneron Agreement, the fully-burdened costs incurred by each of the Company and Regeneron in performing (or having performed) such technology transfer shall also be deducted from net sales of ARCALYST to determine profit. The Company also evenly splits with Regeneron any proceeds received by the Company from any licensees, sublicensees and distributors in consideration for the sale, license or other disposition of rights with respect to ARCALYST, including upfront payments, milestone payments and royalties. For the three and six months ended June 30, 2022, the Company recognized $3,672 and $11,926 respectively, of expenses related to the profit sharing agreement presented within collaboration expenses. The Company recorded $6,000 of profit sharing expense in February 2022 related to the rilonacept Collaboration Agreement that is currently recorded in short-term liabilities. For the three and six months ended June 30, 2021 the Company did not recognize any collaboration expenses related to the profit sharing agreement. ​ Pursuant to the Regeneron Agreement, in September 2017, the parties entered into a clinical supply agreement under which Regeneron agreed to manufacture materials solely for the Company’s use in development activities. Pursuant to the Regeneron Agreement, during the year ended December 31, 2021, the Company entered into a commercial supply agreement under which Regeneron agreed to manufacture product for the Company’s use, including for commercial sales. The commercial supply agreement terminates upon the termination of the Regeneron Agreement or the date of completion of the transfer of technology related to the manufacture of ARCALYST. During the three and six months ended June 30, 2022 and 2021, the Company did not incur any research and development expense related to the purchase of drug materials under the clinical supply agreement. As of June 30, 2022 and December 31, 2021, the Company recorded inventory of $19,916 and $3,675, respectively, related to the purchase of commercial product under the commercial supply agreement (see Note 5). As of June 30, 2022, the Company had non-cancelable purchase commitments under the commercial supply agreement (see Note 14). The Regeneron Agreement will expire when the Company is no longer developing or commercializing any licensed product under the Regeneron Agreement. Either party may terminate the agreement upon the other party’s insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured for 90 days (or 30 days for payment related breaches). Regeneron has the right to terminate the agreement if the Company suspends its development or commercialization activities for a consecutive 12 month period or does not grant a sublicense to a third party to perform such activities, or if the Company challenges any of the licensed patent rights. The Company may terminate the agreement at any time with one year’s written notice. The Company may also terminate the agreement with three months’ written notice if the licensed product is determined to have certain safety concerns. MedImmune License Agreement In December 2017, the Company entered into a license agreement (as amended from time to time, the “MedImmune Agreement”) with MedImmune, Limited (“MedImmune”), pursuant to which MedImmune granted the Company an exclusive, sublicensable, worldwide license to certain intellectual property rights to make, use, develop and commercialize mavrilimumab. Under the MedImmune Agreement, the Company also acquired reference rights to relevant manufacturing and regulatory documents and MedImmune’s existing supply of mavrilimumab drug substance and product. The Company is obligated to use commercially reasonable efforts to develop and commercialize the licensed products. The Company is obligated to make clinical, regulatory and initial sales milestone payments of up to $72,500 in aggregate for the first two indications, of which $57,500 remain as of June 30, 2022. In addition, the Company is obligated to make clinical and regulatory milestone payments of up to $15,000 in the aggregate for each subsequent indication. In July 2020, the Company entered into an amendment to the MedImmune Agreement to establish a new coronavirus field and defer the payment of certain development and regulatory milestones as applied to the new coronavirus field. The Company is obligated to make milestone payments to MedImmune of up to $85,000 upon the achievement of annual net sales thresholds up to, but excluding, $1,000,000 in annual net sales as well as additional milestone payments aggregating up to $1,100,000 upon the achievement of additional specified annual net sales thresholds starting at $1,000,000 and higher. The Company has also agreed to pay tiered royalties on escalating tiers of annual net sales of licensed products starting in the low double-digit percentages and ending at twenty percent. Royalty rates are subject to reductions upon certain events. ​ The Company is solely responsible for all development, manufacturing, and commercial activities and costs of the licensed products, including clinical studies or other tests necessary to support the use of a licensed product. The Company is also responsible for costs related to the filing, prosecution and maintenance of the licensed patent rights. The MedImmune Agreement will expire upon the expiration of the royalty term in the last country for the last indication, as defined in the agreement. Either party may terminate the agreement upon the other party’s insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured for 90 days. MedImmune has the right to terminate the agreement if the Company challenges any of the licensed patent rights. The Company may terminate the agreement at any time upon 90 days’ prior written notice. During the three and six months ended June 30, 2022 and 2021, the Company did not record research and development expense in connection with milestone payments due under the MedImmune Agreement.

Net Loss per Share

Net Loss per Share	6 Months Ended
	Jun. 30, 2022
Net Loss per Share
Net Loss per Share	​ 12. Net Loss per Share The rights, including the liquidation and dividend rights, of the holders of Class A, Class B, Class A1 and Class B1 common shares are identical, except with respect to voting, transferability and conversion (see the Notes to Consolidated Financial Statements to our Form 10-K Basic and diluted net loss per share attributable to common shareholders was calculated as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ 2022 2021 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common shareholders ​ $ (19,981) ​ $ (41,563) ​ $ (45,191) ​ $ (91,047) Denominator: ​ ​ ​ ​ Weighted average common shares outstanding—basic and diluted ​ 69,289,972 ​ 68,395,703 ​ 69,213,860 ​ 68,332,943 Net loss per share attributable to common shareholders— basic and diluted ​ $ (0.29) ​ $ (0.61) ​ $ (0.65) ​ $ (1.33) ​ The Company’s unvested RSUs have been excluded from the computation of basic net loss per share attributable to common shareholders. The Company’s potentially dilutive securities, which include options and unvested RSUs, have been excluded from the computation of diluted net loss per share attributable to common shareholders as the effect would be to reduce the net loss per share attributable to common shareholders. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common shareholders is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common shareholders for the periods indicated because including them would have had an anti-dilutive effect: ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, ​ 2022 2021 Options to purchase common shares 9,573,543 9,448,244 Unvested RSUs 1,158,744 495,773 ​ 10,732,287 9,944,017 ​

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2022
Income Taxes
Income Taxes	13. Income Taxes The Company is an exempted company incorporated under the laws of Bermuda. Under the current laws of Bermuda, income tax is not charged or levied on an exempted company’s income. As a result, the Company has not recorded any income tax benefits from losses incurred in Bermuda during each reporting period, and no net operating loss carryforwards will be available to the Company for those losses. The Company’s wholly owned U.S. subsidiaries, Kiniksa US and Primatope, are subject to federal and state income taxes in the United States. The Company’s wholly owned subsidiary Kiniksa UK, and its wholly owned subsidiaries, Kiniksa Germany, Kiniksa France, and Kiniksa Switzerland are subject to taxation in their respective countries. Certain of the Company’s subsidiaries, primarily Kiniksa US, operate under cost plus arrangements. ​ Although Bermuda has no corporate income tax the Company’s income tax rate for the three and six months ended June 30, 2022 is due to income subject to United States taxation under the Kiniksa US cost plus arrangements with the Company, and U.S. federal and state research tax credits (“R&D credits). Income tax provision for the three and six months ended June 30, 2022 was $716 and $2,641, respectively primarily related to the tax impact from the current tax expense. The current income tax expense is primarily a result of the taxable income earned by Kiniksa US under its cost plus arrangement and required capitalization of R&D expenses offset in part by tax benefits from the U.S. federal and state research and development credits, the Foreign Derived Intangible Income (“FDII”) deduction and share-based compensation taxable events. ​ Management examines all positive and negative evidence to estimate whether sufficient future taxable income will be generated to realize existing deferred tax assets. The Company previously determined it was more likely than not that a majority of its net deferred tax assets would not be realized and concluded that a valuation allowance was required, which eliminated its net deferred tax assets recorded in its balance sheet. In the future, if the Company believes that it is more likely than not that it will realize the benefit of these deferred tax assets, it will adjust the valuation allowance and recognize an income tax benefit. As a result of the license agreement entered into with Genentech, Inc. and F. Hoffman-La Roche Ltd (collectively, “Genentech”) ​

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2022
Commitments and Contingencies
Commitments and Contingencies	14. Commitments and Contingencies License Agreements The Company entered into license agreements with various parties under which it is obligated to make contingent and non-contingent payments (see Note 11). Manufacturing Commitments The Company entered into a commercial supply agreement with Regeneron to provide both clinical supply and commercial product (see Note 11). The Company entered into agreements with several CMOs to provide the Company with preclinical and clinical trial materials. As of June 30, 2022, the Company had committed to minimum payments under these agreements totaling $37,211 all of which are due within one year. Indemnification Agreements The Company is not aware of any claims under indemnification arrangements that are expected to have a material effect on its financial position, results of operations or cash flows, and it has not accrued any liabilities related to such obligations in its consolidated financial statements as of June 30, 2022 or December 31, 2021. Legal Proceedings The Company is not a party to any material litigation and does not have contingency reserves established for any litigation liabilities.

Subsequent Event

Subsequent Event	6 Months Ended
	Jun. 30, 2022
Subsequent Event
Subsequent Event	15. Subsequent Event On August 2, 2022, the Company entered into a license agreement with Genentech, pursuant to which the Company agreed to grant Genentech exclusive rights, including the right to sublicense, to develop and commercialize vixarelimab and related antibodies worldwide. Under the license agreement, the Company will receive upfront and near-term cash payments of $100,000 and will be eligible to receive up to approximately $600,000 in contingent payments, including specified development, regulatory and sales-based milestones. The Company will be eligible to receive tiered royalties on escalating tiers of annual net sales of licensed products ranging from low double digits to mid-teens. The transaction is subject to certain closing conditions, including receipt of antitrust clearance.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2022
Summary of Significant Accounting Policies
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries, Kiniksa Pharmaceuticals Corp. (“Kiniksa US”), Primatope Therapeutics, Inc. (“Primatope”) and Kiniksa Pharmaceuticals (UK), Ltd. (“Kiniksa UK”) as well as the subsidiaries of Kiniksa UK, Kiniksa Pharmaceuticals (Germany) GmbH (“Kiniksa Germany”), Kiniksa Pharmaceuticals (France) SARL (“Kiniksa France”), and Kiniksa Pharmaceuticals GmbH (“Kiniksa Switzerland”), after elimination of all significant intercompany accounts and transactions.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the recognition of revenue, the capitalization of inventory, the accrual for research and development expenses and the valuation of share-based awards. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.
Unaudited Interim Consolidated Financial Information	Unaudited Interim Consolidated Financial Information The accompanying unaudited consolidated financial statements have been prepared in accordance with GAAP for interim financial information. The accompanying unaudited consolidated financial statements do not include all of the information and footnotes required by GAAP for complete consolidated financial statements. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s audited consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (the “2021 Form 10-K”). The Company’s accounting policies are described in the Notes to Consolidated Financial Statements in the Company’s 2021 Form 10-K and updated, as necessary, in this report. The accompanying year-end consolidated balance sheet was derived from audited financial statements but does not include all disclosures required by GAAP. The unaudited interim consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2022 and the results of its operations for the three and six months ended June 30, 2022 and 2021, the changes in its shareholders’ equity for the three and six months ended June 30, 2022 and 2021 and its cash flows for the six months ended June 30, 2022 and 2021. The results for the three and six months ended June 30, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods or any future year or period.
Liquidity	Liquidity The Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the consolidated financial statements are issued. As of June 30, 2022, the Company had an accumulated deficit of $720,588. During the six months ended June 30, 2022, the Company incurred a net loss of $45,191 and used $44,670 cash in operating activities. The Company expects to continue to generate operating losses and cash used in operations for the foreseeable future. As of June 30, 2022, the Company had cash, cash equivalents and short-term investments of $138,208. Based on its current operating plan, the Company expects that its cash, cash equivalents and short-term investments will be sufficient to fund its operations and capital expenditure requirements for at least twelve months from the issuance date of these consolidated financial statements. The future viability of the Company beyond that point is dependent on its ability to fund its operations through sales of ARCALYST and/or raise additional capital, as needed. If the Company is unable to grow sales of ARCALYST in future periods, the Company would need to seek additional financing through public or private securities offerings, debt financings, government funding or grants, or other sources, which may include licensing, collaborations or other strategic transactions or arrangements. Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its commercialization efforts, research and development programs for product candidates or product portfolio expansion, which could adversely affect its business prospects, or the Company may be unable to continue operations.
Revenue Recognition	​ ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”) outlines a five-step process for recognizing revenue from contracts with customers: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the separate performance obligations in the contract, and (v) recognize revenue associated with the performance obligations as they are satisfied. ​ The Company only applies the five-step model to contracts when it is probable that the Company will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. Once a contract is determined to be within the scope of ASC 606, the Company determines the performance obligations that are distinct. The Company recognizes as revenues the amount of the transaction price that is allocated to each respective performance obligation when the performance obligation is satisfied. Generally, the Company’s performance obligations are transferred to customers at a point in time, typically upon delivery of the product to the customer. ​ ASC 606 requires entities to record a contract asset when a performance obligation has been satisfied or partially satisfied, but the amount of consideration has not yet been received because the receipt of the consideration is conditioned on something other than the passage of time. ASC 606 also requires an entity to present a revenue contract as a contract liability in instances when a customer pays consideration, or an entity has a right to an amount of consideration that is unconditional (e.g., receivable), before the entity transfers a good or service to the customer.
Collaboration Revenue	Collaboration Revenue The Company analyzes its collaboration arrangements to assess whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities and therefore within the scope of ASC Topic 808, Collaborative Arrangements (“Topic 808”). This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of Topic 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of Topic 808 and which elements of the collaboration are more reflective of a vendor-customer relationship and therefore within the scope of Topic 606. For elements of collaboration arrangements that are accounted for pursuant to ASC 606, we identify the performance obligations and allocate the total consideration we expect to receive on a relative standalone selling price basis to each performance obligation. Variable consideration such as performance-based milestones will be included in the total consideration if we expect to receive such consideration and if it is probable that the inclusion of the variable consideration will not result in a significant reversal in the cumulative amount of revenue recognized under the arrangement. Our estimate of the total consideration we expect to receive under each collaboration arrangement is updated for each reporting period, and any adjustments to revenue are recorded on a cumulative catch-up basis. We exclude sales-based royalty and milestone payments from the total consideration we expect to receive until the underlying sales occur because the license to our intellectual property is deemed to be the predominant item to which the royalties or milestones relate as it is the primary driver of value in our collaboration arrangements. Key assumptions to determine the standalone selling price may include forecasted revenues, development timelines, reimbursement rates for personnel costs, discount rates and probabilities of technical and regulatory success. We recognize revenue associated with each performance obligation as the control over the promised goods or services transfer to our collaboration partner which occurs either at a point in time or over time. If control transfers over time, revenue is recognized by using a method of measuring progress that best depicts the transfer of goods or services. We evaluate the measure of progress and related inputs each reporting period and any resulting adjustments to revenue are recorded on a cumulative catch-up basis. Consideration received that does not meet the requirements to satisfy ASC 808 or ASC 606 revenue recognition criteria is recorded as deferred revenue in the accompanying consolidated balance sheets, classified as either short-term (less than 12 months) or long-term (more than 12 months) deferred revenue based on our best estimate of when such revenue will be recognized. There have been no other material changes to the significant accounting policies previously disclosed in the Company’s 2021 Form 10-K.
Recently Adopted and Recently Issued Accounting Pronouncements	Recently Adopted Accounting Pronouncements

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2022
Fair Value of Financial Assets and Liabilities
Schedule of financial assets and liabilities measured at fair value on a recurring basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of June 30, 2022 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents — money market funds ​ $ 33,238 ​ $ — ​ $ — ​ $ 33,238 Cash equivalents — U.S. Treasury notes ​ ​ — ​ ​ 6,997 ​ ​ — ​ ​ 6,997 Short-term investments — U.S. Treasury notes ​ ​ — ​ ​ 43,901 ​ ​ — ​ ​ 43,901 ​ ​ $ 33,238 ​ $ 50,898 ​ $ — ​ $ 84,136 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value Measurements ​ ​ as of December 31, 2021 Using: ​ Level 1 Level 2 Level 3 Total Assets: ​ ​ ​ ​ Cash equivalents — money market funds ​ $ 94,324 ​ $ — ​ $ — ​ $ 94,324 Short-term investments — U.S. Treasury notes ​ ​ — ​ ​ 59,731 ​ ​ — ​ ​ 59,731 ​ ​ $ 94,324 ​ $ 59,731 ​ $ — ​ $ 154,055
Schedule of short-term investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Credit ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Losses ​ Value June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Cash Equivalents - U.S. Treasury notes ​ $ 6,998 ​ $ — ​ $ (1) ​ $ — ​ $ 6,997 Short-term investments — U.S. Treasury notes ​ ​ 43,939 ​ ​ — ​ ​ (38) ​ ​ — ​ ​ 43,901 ​ ​ $ 50,937 ​ $ — ​ $ (39) ​ $ — ​ $ 50,898 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ Amortized ​ Unrealized ​ Unrealized ​ Credit ​ Fair ​ ​ Cost ​ Gains ​ Losses ​ Losses ​ Value December 31, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Short-term investments — U.S. Treasury notes ​ $ 59,745 ​ $ 1 ​ $ (15) ​ $ — ​ $ 59,731 ​ ​ $ 59,745 ​ $ 1 ​ $ (15) ​ $ — ​ $ 59,731

Product Revenue, Net (Tables)

Product Revenue, Net (Tables)	6 Months Ended
	Jun. 30, 2022
Product Revenue, Net
Schedule of product revenue, net	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ ​ 2022 ​ 2021 ​ 2022 ​ 2021 Product revenue, net ​ $ 26,972 ​ $ 7,704 ​ $ 49,161 ​ $ 7,704
Schedule of balances and activity of the product revenue allowance and reserve categories	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contractual ​ Government ​ ​ ​ ​ ​ ​ Adjustments ​ Rebates ​ Returns ​ Total Balance at December 31, 2021 ​ $ 515 ​ $ 719 ​ $ 101 ​ $ 1,335 Current provisions relating to sales in the current year ​ ​ 3,303 ​ ​ 1,621 ​ ​ 135 ​ ​ 5,059 Payments/returns relating to sales in the current year ​ ​ (2,255) ​ ​ (448) ​ ​ — ​ ​ (2,703) Payments/returns relating to sales in the prior years ​ ​ (301) ​ ​ (621) ​ ​ — ​ ​ (922) Balance at June 30, 2022 ​ $ 1,262 ​ $ 1,271 ​ $ 236 ​ $ 2,769 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ ​ 2022 ​ 2021 Reduction of accounts receivable ​ $ (130) ​ $ (50) Components of other current liabilities ​ ​ 2,899 ​ ​ 1385 Total revenue-related reserves ​ $ 2,769 ​ $ 1,335

Inventory (Tables)

Inventory (Tables)	6 Months Ended
	Jun. 30, 2022
Inventory
Schedule of inventory	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Raw materials ​ $ — ​ $ — Work-in-process ​ — ​ — Finished Goods ​ ​ 19,916 ​ ​ 3,675 ​ ​ $ 19,916 ​ $ 3,675

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	6 Months Ended
	Jun. 30, 2022
Property and Equipment, Net
Schedule of property and equipment, net	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Furniture, fixtures and vehicles ​ $ 225 ​ $ 62 Computer hardware and software ​ 345 ​ 341 Leasehold improvements ​ ​ 3,931 ​ ​ 3,931 Lab equipment ​ ​ 4,068 ​ ​ 4,249 Construction in progress ​ 10 ​ 166 Total property and equipment ​ ​ 8,579 ​ ​ 8,749 Less: Accumulated depreciation ​ (6,429) ​ (5,915) Total property and equipment, net ​ $ 2,150 ​ $ 2,834

Intangible Assets (Tables)

Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2022
Intangible Assets
Schedule of intangible assets, net of accumulated amortization, impairment charges, and adjustments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, 2022 ​ As of December 31, 2021 ​ ​ Estimated ​ ​ ​ Accumulated ​ ​ ​ ​ ​ Accumulated ​ ​ ​ life Cost Amortization Net ​ Cost Amortization Net Regulatory milestone ​ 20 years ​ $ 20,000 ​ $ 1,250 ​ $ 18,750 ​ $ 20,000 ​ $ 750 ​ $ 19,250 ​ ​ ​ ​ $ 20,000 ​ $ 1,250 ​ $ 18,750 ​ $ 20,000 ​ $ 750 ​ $ 19,250

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2022
Accrued Expenses
Schedule of accrued expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 31, ​ 2022 2021 Accrued research and development expenses ​ $ 14,374 ​ $ 24,977 Accrued employee compensation and benefits ​ ​ 7,410 ​ ​ 8,916 Accrued collaboration expenses ​ ​ 9,612 ​ ​ 835 Accrued legal, commercial and professional fees ​ 2,734 ​ 2,933 Other ​ 370 ​ 370 ​ ​ $ 34,500 ​ $ 38,031

Share-Based Compensation (Table

Share-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2022
Share-Based Compensation
Schedule of share option activity under the Plans	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average ​ ​ Shares ​ Exercise Price Outstanding as of December 31, 2021 9,226,846 ​ $ 14.14 Granted 1,561,160 ​ $ 10.74 Exercised (207,972) ​ $ 5.45 Forfeited (1,006,491) ​ $ 15.60 Outstanding as of June 30, 2022 9,573,543 ​ $ 13.62 Share options exercisable as of June 30, 2022 5,246,401 ​ $ 13.54 Share options unvested as of June 30, 2022 4,327,142 ​ $ 13.72
Schedule of restricted share activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ Average ​ ​ Number of ​ Grant Date ​ ​ Shares ​ Fair Value Unvested RSUs as of December 31, 2021 ​ 885,021 ​ $ 15.72 Granted ​ 655,099 ​ $ 10.71 Vested ​ (170,254) ​ $ 15.79 Forfeited ​ (211,122) ​ $ 14.08 Unvested RSUs as of June 30, 2022 ​ 1,158,744 ​ $ 13.17
Schedule of share-based compensation expense was classified in the consolidated statements of operations and comprehensive loss	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ 2022 2021 ​ 2022 2021 Cost of goods sold ​ $ 112 ​ $ 39 ​ $ 292 ​ $ 39 Research and development expenses ​ ​ 1,608 ​ ​ 1,923 ​ ​ 3,584 ​ ​ 4,557 Selling, general and administrative expenses ​ 4,956 ​ 3,755 ​ 8,831 ​ 8,247 ​ ​ $ 6,676 ​ $ 5,717 ​ $ 12,707 ​ $ 12,843

Out-Licensing Agreements (Table

Out-Licensing Agreements (Tables)	6 Months Ended
	Jun. 30, 2022
Out-licensing Agreements
Schedule of deferred revenue in connection with collaboration agreements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance at ​ ​ ​ ​ ​ ​ Balance at End ​ ​ Beginning of Period ​ Additions ​ Deductions ​ of Period Six Months Ended June 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Huadong rilonacept ​ $ — ​ $ 12,000 ​ $ — ​ $ 12,000 Deferred revenue ​ $ — ​ $ 12,000 ​ $ — ​ $ 12,000

Net Loss per Share (Tables)

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2022
Net Loss per Share
Schedule of basic and diluted net loss per share attributable to common shareholders	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ ​ June 30, ​ June 30, ​ 2022 2021 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common shareholders ​ $ (19,981) ​ $ (41,563) ​ $ (45,191) ​ $ (91,047) Denominator: ​ ​ ​ ​ Weighted average common shares outstanding—basic and diluted ​ 69,289,972 ​ 68,395,703 ​ 69,213,860 ​ 68,332,943 Net loss per share attributable to common shareholders— basic and diluted ​ $ (0.29) ​ $ (0.61) ​ $ (0.65) ​ $ (1.33)
Schedule of anti-dilutive securities excluded from the computation of diluted net loss per share attributable to common shareholders	​ ​ ​ ​ ​ ​ ​ ​ As of June 30, ​ 2022 2021 Options to purchase common shares 9,573,543 9,448,244 Unvested RSUs 1,158,744 495,773 ​ 10,732,287 9,944,017

Nature of the Business and Ba_2

Nature of the Business and Basis of Presentation (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Liquidity
Accumulated deficit	$ 720,588				$ 720,588		$ 675,397
Net losses	19,981	$ 25,210	$ 41,563	$ 49,484	45,191	$ 91,047
Cash used in operations					44,670	$ 78,905
Cash, cash equivalents and short-term investments	$ 138,208				$ 138,208

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022 USD ($) security	Dec. 31, 2021 USD ($) security
Fair Value, Assets Transfers
Fair value of assets transferred from Level 1 to Level 2	$ 0	$ 0
Fair value of assets transferred from Level 2 to Level 1	0	0
Fair value of asset transfer into Level 3	0	0
Fair value of asset transfer out of Level 3	$ 0	$ 0
Number of securities in an unrealized loss position | security	14	11
Securities in unrealized loss position	$ 43,901	$ 49,739
U.S. Treasury Notes
Assets - Fair Value
Short-term investments	50,898	59,731
Short-term investments
Amortized Cost	50,937	59,745
Gross Unrealized Gains		1
Gross Unrealized Losses	(39)	(15)
U.S. Treasury Notes | Cash equivalents
Assets - Fair Value
Short-term investments	6,997
Short-term investments
Amortized Cost	6,998
Gross Unrealized Losses	(1)
U.S. Treasury Notes | Short-term Investments
Assets - Fair Value
Short-term investments	43,901	59,731
Short-term investments
Amortized Cost	43,939	59,745
Gross Unrealized Gains		1
Gross Unrealized Losses	(38)	(15)
Fair Value | Recurring basis
Assets - Fair Value
Assets	84,136	154,055
Fair Value | Recurring basis | Money Market Funds
Assets - Fair Value
Cash equivalents	33,238	94,324
Fair Value | Recurring basis | U.S. Treasury Notes
Assets - Fair Value
Cash equivalents	6,997
Short-term investments	43,901	59,731
Fair Value | Recurring basis | Level 1
Assets - Fair Value
Assets	33,238	94,324
Fair Value | Recurring basis | Level 1 | Money Market Funds
Assets - Fair Value
Cash equivalents	33,238	94,324
Fair Value | Recurring basis | Level 2
Assets - Fair Value
Assets	50,898	59,731
Fair Value | Recurring basis | Level 2 | U.S. Treasury Notes
Assets - Fair Value
Cash equivalents	6,997
Short-term investments	$ 43,901	$ 59,731

Product Revenue, Net (Details)

Product Revenue, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Product revenue
Product revenue, net	$ 26,972	$ 7,704	$ 59,161	$ 7,704
Contractual Adjustments
Balance at beginning of period			515
Current provisions relating to sales in the current year			3,303
Payments/returns relating to sales in the current year			(2,255)
Payments/returns relating to sales in the prior years			(301)
Balance at end of period	1,262		1,262
Government Rebates
Balance at beginning of period			719
Current provisions relating to sales in the current year			1,621
Payments/returns relating to sales in current year			(448)
Payments/returns relating to sales in the prior years			(621)
Balance at end of period	1,271		1,271
Returns
Balance at beginning of period			101
Current provision relating sales in the current year			135
Balance at end of period	236		236
Total
Balance at beginning of period			1,335
Current provisions relating to sales in the current year			5,059
Payments/returns relating to sales in the current year			(2,703)
Payments/returns relating to sales in the prior years			(922)
Balance at end of period	2,769		2,769
Product revenue, net
Product revenue
Product revenue, net	$ 26,972	$ 7,704	$ 49,161	$ 7,704

Product Revenue, Net - Revenue

Product Revenue, Net - Revenue Related Reserves in Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Revenue-related reserves
Revenue-related reserves	$ 2,769	$ 1,335
Accounts receivable, net	7,808	3,985
Accounts receivable, net
Revenue-related reserves
Revenue-related reserves	(130)	(50)
Other current liabilities
Revenue-related reserves
Revenue-related reserves	2,899	1,385
Product revenue, net
Revenue-related reserves
Accounts receivable, net	$ 7,632	$ 3,910

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Inventory
Finished goods	$ 19,916	$ 3,675
Total inventory	$ 19,916	$ 3,675

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Property and Equipment, Net
Total property and equipment	$ 8,579		$ 8,579		$ 8,749
Less: Accumulated depreciation	(6,429)		(6,429)		(5,915)
Total property and equipment, net	2,150		2,150		2,834
Depreciation expense	350	$ 416	709	$ 706
Furniture, fixtures, and vehicles
Property and Equipment, Net
Total property and equipment	225		225		62
Computer hardware and software
Property and Equipment, Net
Total property and equipment	345		345		341
Leasehold improvements
Property and Equipment, Net
Total property and equipment	3,931		3,931		3,931
Lab equipment
Property and Equipment, Net
Total property and equipment	4,068		4,068		4,249
Construction in progress
Property and Equipment, Net
Total property and equipment	$ 10		$ 10		$ 166

Intangible Assets - Finite-live

Intangible Assets - Finite-lived Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Finite-lived intangible asset
Cost	$ 20,000	$ 20,000
Accumulated Amortization	1,250	750
Net intangible assets	$ 18,750	19,250
Regulatory milestone
Finite-lived intangible asset
Estimated life	20 years
Cost	$ 20,000	20,000
Accumulated Amortization	1,250	750
Net intangible assets	$ 18,750	$ 19,250

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accrued Expenses
Accrued research and development expenses	$ 14,374	$ 24,977
Accrued employee compensation and benefits	7,410	8,916
Accrued legal and professional fees	2,734	2,933
Accrued collaboration expenses	9,612	835
Other	370	370
Accrued expenses	$ 34,500	$ 38,031

Share Based Compensation (Detai

Share Based Compensation (Details) - shares		6 Months Ended
	Jan. 01, 2022	Jun. 30, 2022	Dec. 31, 2021
Restricted Share Units (RSUs)
Share-based compensation
RSUs Granted		655,099
Stock options | Class A common shares
Share-based compensation
Shares outstanding (in shares)		9,573,543	9,226,846
Number of options granted		1,561,160
2018 Plan
Share-based compensation
Number of common shares available for future grant		2,659,928
2015 Plan | Class A common shares
Share-based compensation
Shares outstanding (in shares)		2,050,155
2018 ESPP | Class A common shares
Share-based compensation
Number of common shares available for future grant		644,801
2018 ESPP | Class A common shares | Maximum
Share-based compensation
Additional shares authorized	90,000

Share-Based Compensation - Opti

Share-Based Compensation - Options (Details) - Class A common shares - Stock options	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Number of Shares
Outstanding, beginning of the period | shares	9,226,846
Granted | shares	1,561,160
Exercised | shares	(207,972)
Forfeited | shares	(1,006,491)
Outstanding, end of the period | shares	9,573,543
Options exercisable | shares	5,246,401
Options unvested | shares	4,327,142
Weighted Average Grant Date Fair Value
Outstanding, beginning of the period | $ / shares	$ 14.14
Granted | $ / shares	10.74
Exercised | $ / shares	5.45
Forfeited | $ / shares	15.60
Outstanding, end of the period | $ / shares	13.62
Options exercisable | $ / shares	13.54
Options unvested | $ / shares	$ 13.72

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Shares and RSUs (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based compensation
Share-based compensation expense		$ 6,676	$ 5,717	$ 12,707	$ 12,843
Restricted Share Units (RSUs)
Share-based compensation
Share-based compensation expense		$ 932	$ 526	$ 1,551	$ 2,030
Number of shares
Beginning of the period				885,021
Granted				655,099
Vested				(170,254)
Forfeited				(211,122)
End of the period		1,158,744		1,158,744
Weighted Average Fair Value at Issuance
Beginning of the period				$ 15.72
Granted				10.71
Vested				15.79
Forfeited				14.08
End of the period		$ 13.17		$ 13.17
Time-based RSUs
Share-based compensation
Vesting percentage	25%

Share-Based Compensation - Clas

Share-Based Compensation - Classification of Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based compensation
Share-based compensation expense	$ 6,676	$ 5,717	$ 12,707	$ 12,843
Cost of goods sold
Share-based compensation
Share-based compensation expense	112	39	292	39
Research and development expenses
Share-based compensation
Share-based compensation expense	1,608	1,923	3,584	4,557
Selling, general and administrative expenses
Share-based compensation
Share-based compensation expense	4,956	3,755	8,831	8,247
Stock options
Share-based compensation
Total unrecognized compensation cost	37,588		$ 37,588
Expenses expected to be recognized over a weighted average remaining period			2 years 6 months 10 days
Restricted Share Units (RSUs)
Share-based compensation
Share-based compensation expense	932	$ 526	$ 1,551	$ 2,030
Total unrecognized compensation cost	$ 12,743		$ 12,743
Expenses expected to be recognized over a weighted average remaining period			3 years 2 months 26 days

Out-Licensing Agreements (Detai

Out-Licensing Agreements (Details) $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 21, 2022 USD ($) item agreement	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Collaborative agreements
Product revenue, net		$ 26,972	$ 7,704	$ 59,161	$ 7,704
Collaboration revenue
Collaborative agreements
Product revenue, net				10,000
Collaboration Agreements | Huadong rilonacept
Collaborative agreements
Notice period to terminate the agreement	12 months
Collaboration Agreements | Huadong rilonacept
Collaborative agreements
Number of agreements entered into | agreement	2
Upfront payments received	$ 22,000
Term of agreement for royalty payments	12 years
Notice period to terminate the agreement if there is no material development or commercialization activities with respect to the licensed product in China	60 days
Collaboration Agreements | Huadong rilonacept | Minimum
Collaborative agreements
Time period threshold of continuous material development or commercialization activities in China that, if not met, can trigger the right for the Company to terminate the agreement	6 months
Territory License - Rilonacept | Huadong rilonacept
Collaborative agreements
Upfront payments received	$ 12,000
Number of performance obligations in an agreement | item	1
Transaction price				12,000
Territory License - Rilonacept | Huadong rilonacept | Maximum
Collaborative agreements
Payments to be received by the company upon the achievement of specified development, regulatory and sales milestones	$ 70
Territory License - Mavrilimumab | Collaboration revenue
Collaborative agreements
Product revenue, net				10,000
Territory License - Mavrilimumab | Huadong rilonacept
Collaborative agreements
Upfront payments received	$ 10,000
Number of performance obligations in an agreement | item	2
Transaction price				$ 10,000
Territory License - Mavrilimumab | Huadong rilonacept | Maximum
Collaborative agreements
Payments to be received by the company upon the achievement of specified development, regulatory and sales milestones	$ 576

Out-Licensing Agreements - Defe

Out-Licensing Agreements - Deferred Revenue (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($)
Collaborative agreements
Additions	$ 12,000
Balance at end of period	12,000
Territory License - Rilonacept | Huadong rilonacept
Collaborative agreements
Additions	12,000
Balance at end of period	12,000
Territory License - Rilonacept | Huadong rilonacept | Collaboration revenue
Collaborative agreements
Revenue recognized	$ 0

In-license, Acquisition and C_2

In-license, Acquisition and Collaboration Agreements - Biogen Asset Purchase Agreement (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
License and Acquisition Agreements
Uncured period which causes termination of the agreement, due to insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured	90 days
Notice period to terminate the agreement under payment-related breaches	30 days
Research and development			$ 13,798	$ 23,945	$ 34,615	$ 52,628
Asset Purchase Agreement | Biogen
License and Acquisition Agreements
Remaining milestone payments to be paid upon clinical and regulatory milestone achievement			$ 165,000		165,000
Maximum aggregate obligation to pay insignificant annual maintenance fees as well as clinical and regulatory milestone payments		$ 1,575
Notice period to terminate the agreement		90 days
Uncured period which causes termination of the agreement, due to insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured		90 days
Notice period to terminate the agreement under payment-related breaches		30 days
Research and development				$ 14	$ 34	$ 28
Asset Purchase Agreement | Biogen | Maximum
License and Acquisition Agreements
Milestone payment to be paid upon clinical and regulatory milestone achievement		$ 179,000
Milestone payment to be paid upon net sales milestone achievement		$ 150,000

In-license, Acquisition and C_3

In-license, Acquisition and Collaboration Agreements - Beth Israel Deaconess Medical Center License Agreement (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
License and Acquisition Agreements
Research and development	$ 13,798	$ 23,945	$ 34,615	$ 52,628
License Agreement | BIDMC
License and Acquisition Agreements
Research and development	0	$ 0	0	$ 0
License Agreement | BIDMC | Maximum
License and Acquisition Agreements
Milestone payment to be paid upon clinical and regulatory milestone achievement	$ 1,200		$ 1,200

In-license, Acquisition and C_4

In-license, Acquisition and Collaboration Agreements - Regeneron License Agreement (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended			6 Months Ended
	Feb. 28, 2022	Sep. 30, 2017	Jun. 30, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
License and Acquisition Agreements
Research and development			$ 13,798	$ 23,945		$ 34,615	$ 52,628
Uncured period which causes termination of the agreement, due to insolvency or bankruptcy or for material breach of the agreement by the other party that remains uncured		90 days
Notice period to terminate the agreement under payment-related breaches		30 days
Consecutive suspension of activities period for termination of agreement		12 months
Notice period to terminate the agreement		1 year
Notice period to terminate the agreement if products are having safety concerns		3 months
Intangible asset - Regulatory milestone			20,000			20,000		$ 20,000
Commercial product inventory			19,916			19,916		3,675
Regulatory milestone
License and Acquisition Agreements
Intangible asset - Regulatory milestone			20,000			20,000		20,000
Regeneron | License Agreement
License and Acquisition Agreements
Regulatory milestone payment					$ 20,000
Profit sharing recognized			3,672			11,926	$ 0
Regeneron | License Agreement | Regulatory milestone
License and Acquisition Agreements
Intangible asset - Regulatory milestone			20,000			20,000
Regeneron | License Agreement | Short-term liabilities
License and Acquisition Agreements
Profit sharing recognized	$ 6,000
Regeneron | Clinical Supply Agreement
License and Acquisition Agreements
Commercial product inventory			$ 19,916			$ 19,916		$ 3,675

In-license, Acquisition and C_5

In-license, Acquisition and Collaboration Agreements - MedImmune License Agreement (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Jul. 31, 2020	Sep. 30, 2017	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2017
License and Acquisition Agreements
Notice period to terminate the agreement by both parties for material breaches		90 days
Research and development			$ 13,798	$ 23,945	$ 34,615	$ 52,628
MedImmune | License Agreement
License and Acquisition Agreements
Remaining milestone payments to be paid upon clinical and regulatory milestone achievement			57,500		57,500
Annual net sales excluded from calculation of specified annual net sales thresholds	$ 1,000,000
Maximum percentage of royalty payable on annual net sales of licensed products	20%
Notice period to terminate the agreement by both parties for material breaches	90 days
Notice period to terminate the agreement	90 days
Research and development			$ 0	$ 0	$ 0	$ 0
Minimum | MedImmune | License Agreement
License and Acquisition Agreements
Additional specified annual net sales threshold for additional milestone payment.	$ 1,000,000
Maximum | MedImmune | License Agreement
License and Acquisition Agreements
Milestone payment to be paid upon specified milestone achievements for first two indications							$ 72,500
Milestone payment to be paid upon clinical and regulatory milestone achievement							$ 15,000
Milestone payment to be paid upon specified annual sales milestone achievements	85,000
Additional specified annual net sales threshold for additional milestone payment.	$ 1,100,000

Net Loss per Share (Details)

Net Loss per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Numerator:
Net loss attributable to common shareholders	$ (19,981)	$ (25,210)	$ (41,563)	$ (49,484)	$ (45,191)	$ (91,047)
Denominator:
Weighted average common shares outstanding-basic	69,289,972		68,395,703		69,213,860	68,332,943
Weighted average common shares outstanding-diluted	69,289,972		68,395,703		69,213,860	68,332,943
Net loss per share attributable to common shareholders-basic	$ (0.29)		$ (0.61)		$ (0.65)	$ (1.33)
Net loss per share attributable to common shareholders-diluted	$ (0.29)		$ (0.61)		$ (0.65)	$ (1.33)

Net Loss per Share - Anti-Dilut

Net Loss per Share - Anti-Dilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Anti-dilutive securities excluded from computation of earnings per share
Total, anti-dilutive securities excluded from computation of earnings per share	10,732,287	9,944,017
Stock options
Anti-dilutive securities excluded from computation of earnings per share
Total, anti-dilutive securities excluded from computation of earnings per share	9,573,543	9,448,244
Restricted Share Units (RSUs)
Anti-dilutive securities excluded from computation of earnings per share
Total, anti-dilutive securities excluded from computation of earnings per share	1,158,744	495,773

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Income Taxes
Bermuda statutory income tax rate			0%
Net operating loss carryforwards - Bermuda	$ 0	$ 0	$ 0	$ 0
Income tax expense	$ 716	$ 1,014	$ 2,641	$ 1,224

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	Jun. 30, 2022 USD ($)
Manufacturing commitments
Non-cancelable purchase commitments	$ 37,211

Subsequent Event (Details)

Subsequent Event (Details) - Subsequent event - Collaborative Arrangement, Transaction with Party to Collaborative Arrangement [Member] - Genentech $ in Thousands	Aug. 02, 2022 USD ($)
Subsequent event
Upfront payment due per agreement	$ 100,000
Maximum
Subsequent event
Milestone receipts	$ 600,000