CRISPR Therapeutics (CRSP) 10-Q 11 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	May 08, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Trading Symbol	CRSP
Entity Registrant Name	CRISPR THERAPEUTICS AG
Entity Central Index Key	1,674,416
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		39,997,525

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash	$ 288,872	$ 315,520
Accounts receivable, including related party amounts of $1,057 and $752 as of March 31, 2017 and December 31, 2016, respectively	5,672	3,157
Prepaid expenses and other current assets including related party amounts of $577 and $0 as of March 31, 2017 and December 31, 2016, respectively	1,918	1,511
Total current assets	296,462	320,188
Property and equipment, net	22,165	21,027
Intangible assets, net	385	399
Restricted cash	3,151	3,150
Other non-current assets	183	198
Total assets	322,346	344,962
Current liabilities:
Accounts payable	3,937	4,569
Accrued expenses, including related party amounts of $219 and $537 as of March 31, 2017 and December 31, 2016, respectively	11,699	16,320
Accrued tax liabilities	190	23
Deferred rent	1,027	1,027
Other current liabilities	62	59
Total current liabilities	16,915	21,998
Deferred revenue, including related party amounts of $420 and $527 as of March 31, 2017 and December 31, 2016, respectively	78,311	77,646
Deferred rent non-current	11,768	12,283
Other non-current liabilities	177	189
Total liabilities	107,171	112,116
Commitments and contingencies (Note 6)
Shareholders' equity:
Common shares, CHF 0.03 par value	1,216	1,216
Treasury shares, at cost, 444,873 shares at March 31, 2017 and December 31, 2016	0	0
Additional paid-in capital	292,519	288,739
Accumulated deficit	(78,558)	(57,083)
Accumulated other comprehensive loss	(2)	(26)
Total shareholders' equity	215,175	232,846
Total liabilities and shareholders' equity	$ 322,346	$ 344,962

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) $ in Thousands	Mar. 31, 2017USD ($)shares	Dec. 31, 2016USD ($)shares
Statement of Financial Position [Abstract]
Accounts receivable, related party amount, current	$ 1,057	$ 752
Prepaid expenses and other current assets, related party amount	577	0
Accrued expenses related party amount, current	219	537
Deferred revenue related party amount	$ 420	$ 527
Treasury stock, shares | shares	444,873	444,873

Condensed Consolidated Statemen

Condensed Consolidated Statement of Operations and Comprehensive Loss - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Collaboration revenue	[1]	$ 2,703	$ 476
Operating expenses:
Research and development	[2]	14,805	6,012
General and administrative		8,642	6,116
Total operating expenses		23,447	12,128
Loss from operations		(20,744)	(11,652)
Other (expense) income:
Interest expense			(8,050)
Loss from equity method investment		(446)
Gain on extinguishment of convertible loan			11,482
Other expense, net		(6)	(146)
Total other (expense) income, net		(452)	3,286
Net loss before income taxes		(21,196)	(8,366)
Provision for income taxes		(279)	(76)
Net loss		(21,475)	(8,442)
Foreign currency translation adjustment		24	(4)
Comprehensive loss		(21,451)	(8,446)
Reconciliation of net loss to net loss attributable to common shareholders:
Net loss		(21,475)	(8,442)
Loss attributable to noncontrolling interest			3
Net loss attributable to common shareholders		$ (21,475)	$ (8,439)
Net loss per share attributable to common shareholders-basic and diluted		$ (0.54)	$ (1.53)
Weighted-average common shares outstanding used in net loss per share attributable to common shareholders-basic and diluted		39,725,947	5,528,079
[1]	Including the following amounts of revenue from a related party, see Note 11:
[2]	Including the following amounts of research and development expense with a related party, see Note 11:

Condensed Consolidated Stateme5

Condensed Consolidated Statement of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Revenue from related party	$ 1,164
Research and development expense with a related party	$ 1,136	$ 269

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities:
Net loss	$ (21,475)	$ (8,442)
Reconciliation of net loss to net cash used in operating activities:
Depreciation and amortization	720	106
Equity-based compensation	3,746	1,022
Non-cash interest expense		8,050
Loss from disposal of property and equipment		28
Unrealized foreign currency remeasurement loss	1	11
Gain on extinguishment of convertible loan		(11,482)
Changes in:
Restricted cash	(1)	(2)
Accounts receivable	(2,515)	(626)
Prepaid expenses and other assets	(394)	(993)
Accounts payable and accrued expenses	(3,648)	1,956
Deferred revenue	665	151
Deferred rent	(515)	172
Other liabilities, net	4	35
Net cash used in operating activities	(23,412)	(10,014)
Investing activities:
Purchase of property and equipment	(3,285)	(232)
Proceeds from contribution of intellectual property to equity method investee		20,000
Cash investment in equity method investee		(100)
Net cash (used in) provided by investing activities	(3,285)	19,668
Financing activities:
Proceeds from exercise of options	20
Proceeds from issuance of convertible loans		35,000
Net cash provided by financing activities	20	35,000
Effect of exchange rate changes on cash	29	(15)
(Decrease) increase in cash	(26,648)	44,639
Cash, beginning of period	315,520	155,961
Cash, end of period	288,872	200,600
Supplemental disclosure of non-cash investing and financing activities
Property and equipment purchases in accounts payable and accrued expenses	$ 973	116
Conversion of Vertex convertible loan and accrued interest		61,929
Noncash contribution of intellectual property to Casebia LLP		$ 36,372

Organization and Operations

Organization and Operations	3 Months Ended
	Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Operations	1. Organization and Operations The Company CRISPR Therapeutics AG (“CRISPR” or the “Company”) was formed on October 28, 2013 in Basel, Switzerland. The Company was established to translate CRISPR/Cas9, a genome editing technology, into transformative gene-based medicines for the treatment of serious human diseases. The foundational intellectual property underlying the Company’s operations was licensed to the Company and its subsidiaries in April 2014. The Company devotes substantially all of its efforts to product research and development activities, initial market development and raising capital. The Company’s principal offices are located in Basel, Switzerland and its principal research operations are in Cambridge, Massachusetts. On January 23, 2014, the founders of the Company formed TRACR Hematology Limited (“TRACR”) in the United Kingdom, to further the development of the CRISPR/Cas9 technology into medicines for the treatment of blood-borne illnesses. As the Company was funding and managing TRACR’s operations in 2014, it has been consolidated by the Company from the date that the Company established a variable interest in TRACR in April 2014. In March 2015, the Company acquired 82.1% of the outstanding equity of TRACR in a share exchange transaction. Concurrent with its initial public offering (“IPO”) in October 2016, the Company acquired the outstanding non-controlling interest in TRACR, and as such, as of March 31, 2017, TRACR is a wholly-owned subsidiary of the Company. On February 7, 2014, the Company formed a wholly-owned subsidiary in the United Kingdom, CRISPR Therapeutics Limited (“CRISPR Ltd.”), and on February 16, 2015, the Company formed a wholly-owned subsidiary in the United States, CRISPR Therapeutics, Inc. (“CRISPR Inc.”), as its principal research and development operation. The Company is subject to risks common to companies in the biotechnology industry, including but not limited to, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval for any drug product candidate that it may identify and develop, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations and ability to transition from pilot-scale manufacturing to large-scale production of products. The Company had an accumulated deficit of $78.6 million as of March 31, 2017 and has financed its operations to date from proceeds obtained from its IPO, a series of preferred shares and convertible loan issuances, and upfront fees received under its collaboration and joint venture arrangements. The Company will require substantial additional capital to fund its research and development and ongoing operating expenses. Liquidity The Company expects its cash of $288.9 million at March 31, 2017 to be sufficient to fund its current operating plan for at least the next 24 months. Thereafter, the Company may be required to obtain additional funding. There can be no assurance that the Company will be able to obtain additional debt or equity financing or generate product revenue or revenues from collaborative partners, on terms acceptable to the Company, on a timely basis or at all. The failure of the Company to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on the Company’s business, results of operations, and financial condition.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note 2, “Summary of Significant Accounting Policies,” in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016 (the “Annual Report”). There have been no material changes to the significant accounting policies during the three months ended March 31, 2017. Unaudited Interim Financial Information The condensed consolidated financial statements of the Company included herein have been prepared, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted from this report, as is permitted by such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Annual Report. Basis of Presentation and Use of Estimates The accompanying condensed consolidated financial statements have been prepared in conformity with GAAP, and include the accounts of (i) the Company, and (ii) its wholly-owned subsidiaries, CRISPR Ltd., CRISPR Inc., and TRACR. All intercompany accounts and transactions have been eliminated. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) of the Financial Accounting Standards Board (“FASB”). The Company accounts for its 50% investment in Casebia Therapeutics LLP (“Casebia”) under the equity method of accounting. See Note 7 for further details. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. On an ongoing basis, the Company’s management evaluates its estimates, which include, but are not limited to, equity-based compensation expense, revenue recognition, equity method investments, and reported amounts of expenses during the period. Significant estimates in these condensed consolidated financial statements have been made in connection with the calculation of revenues, research and development expenses, equity-based compensation expense, fair value of intangible assets, and the provision for or benefit from income taxes. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable under the circumstances. Actual results may differ from those estimates or assumptions. Net Loss Per Share Attributable to Common Shareholders Basic net income (loss) per share is calculated by dividing net income (loss) attributable to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted net income per share is calculated by dividing the net income attributable to common shareholders by the weighted-average number of common equivalent shares outstanding for the period, including any dilutive effect from outstanding stock options and warrants using the treasury stock method. The following common share equivalents, presented on an as converted basis, were excluded from the calculation of net loss per share for the periods presented, due to their anti-dilutive effect (in common stock equivalent shares): Three Months Ended March 31, 2017 2016 Convertible preferred shares — 24,301,632 Dr. Emmanuelle Charpentier call option — 328,017 Outstanding options 4,829,891 2,384,908 Unvested unissued restricted common shares 80,987 142,794 Total 4,910,878 27,157,351 Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers Revenue from Contracts with Customers Revenue from Contracts with Customers Principal versus Agent Considerations Revenue from Contracts with Customers Identifying Performance Obligations and Licensing Revenue from Contracts with Customers Narrow-Scope Improvements and Practical Expedients The Revenue ASUs noted above provide an accounting standard for a single comprehensive model for use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. The accounting standard is effective for interim and annual periods beginning after December 15, 2017, with an option to early adopt for interim and annual periods beginning after December 15, 2016. The guidance permits two methods of adoption: retrospectively to each prior reporting period presented (the full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (the modified retrospective method). The Company currently anticipates adopting the new standard effective January 1, 2018 under the full retrospective method. The Company is in the process of determining the impact of the Revenue ASUs on its financial statements as it relates to their two revenue generating collaboration agreements. In February 2016, the FASB issued ASU No. 2016-02, Leases In October 2016, the FASB issued ASU No. 2016-16, Income Taxes Intra-Entity Transfers of Assets Other Than Inventory In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows Restricted Cash In January 2017, the FASB issued ASU No. 2017-01, Business Combinations In January 2017, the FASB issued ASU No. 2017-03, Accounting Changes and Error Corrections and Investments—Equity Method and Joint Ventures Measurement of Credit Losses on Financial Instruments, 606 – Revenue from Contracts with Customers, Leases In January 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other

Property and Equipment, net

Property and Equipment, net	3 Months Ended
	Mar. 31, 2017
Property, Plant and Equipment [Abstract]
Property and Equipment, net	3. Property and Equipment, net Property and equipment, net, consists of the following (in thousands): As of March 31, December 31, 2017 2016 Computer equipment and software $ 110 $ 110 Furniture, fixtures, and other 2,044 2,044 Laboratory equipment 4,728 2,970 Leasehold improvements 15,765 15,780 Construction work in process 1,165 1,065 23,812 21,969 Accumulated Depreciation (1,647 ) (942 ) Property and equipment, net $ 22,165 $ 21,027 Depreciation expense was $0.7 million, and $0.1 million, for the three months ended March 31, 2017 and 2016, respectively.

Accrued Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2017
Payables and Accruals [Abstract]
Accrued Expenses	4. Accrued Expenses Accrued expenses consist of the following (in thousands): As of March 31, December 31, Payroll and employee-related costs $ 1,570 $ 2,585 Research costs 490 996 Licensing fees 1,111 492 Professional fees 1,873 2,715 Intellectual property costs 1,700 3,372 Accrued property and equipment 4,697 5,081 Other 258 1,079 Total $ 11,699 $ 16,320

Convertible Loans

Convertible Loans	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Convertible Loans	5. Convertible Loans 2015 Convertible Loan Agreement with Vertex and certain existing shareholders On October 26, 2015, the Company entered into a convertible loan agreement with Vertex Pharmaceuticals Incorporated (“Vertex”) and certain existing shareholders (the “Vertex Convertible Loan”) under which the Company borrowed $38.2 million. The Vertex Convertible Loan accrued interest at 2.5% per annum and had an initial maturity date of April 26, 2016 subject to acceleration upon the occurrence of certain conditions. The Vertex Convertible Loan included various embedded conversion, redemption and other features, none of which required separate accounting from the host instrument under ASC Topic 815: Derivatives and Hedging The conversion terms, redemption terms, and other features of the Vertex Convertible Loan are included in the Annual Report. Convertible Loan with Bayer Global Investments B.V. On January 29, 2016, concurrent with the execution of an agreement to establish a Joint Venture (“JV”) with Bayer HealthCare LLC (“Bayer HealthCare”), the Company entered into a Convertible Loan Agreement (the “Bayer Convertible Loan”) with Bayer Global Investments B.V. (“Bayer BV”) under which the Company borrowed $35.0 million. The Bayer Convertible Loan accrued interest at 2.0% per annum and matured on January 29, 2016. The Bayer Convertible Loan included various embedded conversion, redemption and other features, none of which required separate accounting from the host instrument under ASC 815. The conversion terms, redemption terms, and other features of the Bayer Convertible Loan are included in the Annual Report. Conversion of Convertible Loans to Series B Preferred Shares On January 29, 2016, concurrent with the issuance of the Bayer Convertible Loan, all of the outstanding principal under the $35.0 million Bayer Convertible Loan automatically converted into 2,605,330 Series B Redeemable Convertible Preferred Shares (“Series B Preferred Shares”) at $13.43 per share. The Company determined the fair value of the Bayer Convertible Loan to be $24.5 million based on the fair value of the underlying Series B Preferred Shares that were exchanged as part of the immediate conversion. As the Bayer Convertible Loan was executed in contemplation of the joint venture agreement with Bayer, the Company evaluated the Bayer Convertible Loan as part of one multiple-element arrangement and, using a relative fair value allocation method, allocated $27.0 million of aggregate arrangement consideration to the Bayer Convertible Loan upon issuance. Upon conversion, the Company accreted the Bayer Convertible Loan to its face value of $35.0 million through a charge to interest expense of $8.0 million and converted the $35.0 million to Series B Preferred Shares under the conversion model. The receipt of $35.0 million in proceeds under the Bayer Convertible Loan in exchange for equity securities, combined with the $38.2 million in proceeds from Vertex Convertible Loan, triggered an automatic conversion provision of the Vertex Convertible Loan Agreement. Accordingly, on January 29, 2016, the Vertex Convertible Loan, including loans from existing shareholders, plus accrued interest also converted into 2,859,278 of Series B Preferred Shares at $13.43 per share. The Company determined the fair value of the Vertex Convertible Loan to be $26.9 million based on the fair value of the underlying Series B Preferred Shares that were exchanged as part of the conversion. Upon extinguishment, the Company recorded a gain on extinguishment of $11.5 million for the difference between the carrying value of the debt and the fair value of the Series B Preferred Shares issued to settle the debt under the general extinguishment model.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies Operating Leases In March 2017, the Company entered into a sublease for a portion of one research and office facility effective April 1, 2017. The sublease term is less than the remaining term under the original lease, and as a result, the Company does not believe it has met a cease use date as it may re-enter the space following the sublease. Net payments to be received under the sublease are consistent with scheduled rent payments under the original lease. Litigation The Company licenses a U.S. patent application that is currently subject to interference proceedings declared by the Patent Trial and Appeal Board (“PTAB”) of the U.S. Patent and Trademark Office. Following motions by the parties and other procedural matters, the PTAB concluded in February 2017 that the declared interference should be dismissed because the claim sets of the two parties were not directed to the same patentable invention in accordance with the PTAB’s two-way test for patent interferences. In April 2017, the Regents of the University of California (“California”) appealed the PTAB decision to the U.S. Court of Appeals for the Federal Circuit. In the appeal, California is seeking review and reversal of the PTAB’s February 2017 decision, which terminated the interference without determining which inventors actually invented the use of the CRISPR/Cas9 genome editing technology in eukaryotic cells. Under the Invention Management Agreement signed on December 15, 2016, the Company is obligated to share costs related to patent maintenance, defense and prosecution. The Company incurred $0.5 million and $0.6 million, for the three months ended March 31, 2017 and 2016, respectively, in shared costs. The Company recorded accrued legal costs from the cost sharing of $0.9 million and $2.8 million as of March 31, 2017 and December 31, 2016, respectively.

Significant Contracts

Significant Contracts	3 Months Ended
	Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Significant Contracts	7. Significant Contracts Intellectual Property Agreements CRISPR Therapeutics AG—Charpentier License Agreement In April 2014, the Company entered into a technology license agreement with Dr. Charpentier pursuant to which the Company licensed certain intellectual property rights under joint ownership from Dr. Charpentier to develop and commercialize products for the treatment or prevention of human diseases other than hemoglobinopathies (“CRISPR—Charpentier License Agreement”). In consideration for the granting of the license, the Company paid Dr. Charpentier an upfront fee of CHF 0.1 million ($0.1 million), and agreed to pay an immaterial annual license maintenance fee if Dr. Charpentier is not otherwise engaged in a service arrangement with the Company. During the years ended December 31, 2016 and 2015, and three months ended March 31, 2017 and 2016, Dr. Charpentier has been in a consulting arrangement with the Company, as such, no annual payments have been made under this provision. Dr. Charpentier is entitled to receive nominal clinical milestone payments. The Company is also obligated to pay Dr. Charpentier a low single digit percentage of sublicensing payments received under any sublicense agreement with a third party. In addition, the Company is also obligated to pay to Dr. Charpentier a low single-digit percentage royalty based on annual net sales of licensed products and licensed services by the Company and its affiliates and sublicensees. During the three months ended March 31, 2017 and 2016, the Company recorded $0 and $0.3 million, respectively, of sublicensing fees due to Dr. Charpentier. These expenses were under the terms of the CRISPR—Charpentier License Agreement that was triggered by the execution of the Bayer Agreement (“Bayer Agreement”). TRACR Hematology Limited—Charpentier License Agreement In April 2014, TRACR entered into a technology license agreement (“TRACR—Charpentier License Agreement”) with Dr. Charpentier pursuant to which TRACR licensed certain intellectual property rights under joint ownership from Dr. Charpentier to develop and commercialize products for the treatment or prevention of human diseases related to hemoglobinopathies. In consideration for the granting of the license, Dr. Charpentier is entitled to receive nominal clinical milestone payments. TRACR is also obligated to pay Dr. Charpentier a low single digit percentage of sublicensing payments received under any sublicense agreement with a third party. In addition, TRACR is obligated to pay to Dr. Charpentier low single digit percentage royalties based on annual net sales of licensed products and licensed services by the Company and its affiliates and sublicensees. During the three months ended March 31, 2017 and 2016, the Company did not record any sublicensing fees due to Dr. Charpentier under the terms of the TRACR—Charpentier License Agreement. Patent Assignment Agreement In November 2014, the Company entered into a patent assignment agreement (“Patent Assignment Agreement”) with Dr. Charpentier, Dr. Ines Fonfara, and the University of Vienna (collectively, the “Assignors”), pursuant to which the Company received from the assignors all rights, title and interest in and to certain patent rights claimed in the U.S. Patent Application No.61/905,835. In consideration for the assignment of such rights, the Assignors are entitled to receive clinical milestone payments totaling up to €0.3 million (approximately $0.4 million) in the aggregate for the first human therapeutic product. The Company is also obligated to pay to the Assignors low single digit royalties based on annual net sales of certain products and services by the Company and its affiliates and sublicensees. During the three months ended March 31, 2017 and 2016, the Company recorded $0 and $19 thousand, respectively, of sublicensing fees due to the Assignors under the terms of the Patent Assignment Agreement that was triggered under the Vertex collaboration agreement and by the execution of the Bayer Agreement. Collaboration Agreement with Vertex Pharmaceuticals, Incorporated On October 26, 2015, the Company entered into a strategic collaboration, option, and license agreement (“Collaboration Agreement”) with Vertex, focused on the use of CRISPR’s gene editing technology, CRISPR/Cas9, to discover and develop potential new treatments aimed at the underlying genetic causes of human disease. During the three months ended March 31, 2017 and 2016, the Company recognized $1.5 million and $0.5 million of revenue related to the collaboration with Vertex. Research and development expense incurred by the Company in relation to its performance under the Collaboration Agreement for the three months ended March 31, 2017 and 2016 was $2.6 million and $0.6 million, respectively. As of March 31, 2017 and December 31, 2016, there was $77.9 million and $77.1 million of non-current deferred revenue related to the Company’s collaboration with Vertex, respectively. Joint Venture with Bayer Healthcare LLC On December 19, 2015, the Company entered into an agreement with Bayer HealthCare LLC to establish the JV to discover, develop and commercialize new therapeutics to cure blood disorders, blindness, and congenital heart disease. On February 12, 2016, the Company and Bayer HealthCare completed the formation of the joint venture entity, Casebia. CRISPR contributed its proprietary CRISPR/Cas9 gene editing technology and intellectual property for selected disease indications and Bayer HealthCare contributed its protein engineering expertise and relevant disease know-how. At March 31, 2017 and December 31, 2016, the Company’s equity method investment in Casebia was zero. During the three months ended March 31, 2017 and 2016, the Company recognized $1.2 million and $0 of revenue, respectively, related to the collaboration with Casebia. During the three months ended March 31, 2017 and 2016, the Company recognized $1.1 million and $0 of research and development expense, respectively, in relation to its performance under the agreement. During the three months ended March 31, 2017 and 2016, the Company recognized $0.5 million and $0, respectively, of stock-based compensation expense related to Casebia employees. Non-current deferred revenue related to the Company’s collaboration with Casebia was $0.4 million and $0.5 million as of March 31, 2017 and December 31, 2016, respectively. Unrecognized equity method losses in excess of the Company’s equity investment in Casebia was $6.5 million and $4.0 million as of March 31, 2017 and December 31, 2016, respectively. Total operating expenses, and net loss of Casebia for the three months ended March 31, 2017 was $5.5 million. During the three months ended March 31, 2016, total operating expenses and net loss of Casebia was $73.8 million which included research and development expenses of $71.4 million for the fair value of the CRISPR license acquired.

Share Capital

Share Capital	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Share Capital	8. Share Capital The Company had 40,258,364 registered common shares as of March 31, 2017, with a par value of CHF 0.03 per share, which includes 80,987 shares of unvested unissued restricted common stock and 444,873 treasury shares which are legally outstanding but not considered outstanding for accounting purposes. Conditional Capital Reserved for Future Issuance The Company had the following conditional capital reserved for future issuance: As of Conditional Capital March 31, 2017 December 31, 2016 Unvested unissued restricted stock 166,667 166,667 Outstanding stock options 4,829,891 4,535,371 Reserved for future issuance under stock option plans 4,996,123 5,290,643 Shares available for bonds and similar debt instruments 4,919,700 4,919,700 Shares available for employee purchase plans 413,226 413,226 Total 15,325,607 15,325,607

Equity-based Compensation

Equity-based Compensation	3 Months Ended
	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity-based Compensation	9. Equity-based Compensation The Company uses the straight-line attribution method to recognize stock-based compensation expense for stock options and restricted stock awards. Stock options and restricted stock awards generally vest over four years with 25% vesting on the first anniversary of service commencement and the remaining 75% vesting monthly thereafter. Effective January 1, 2017, the company adopted ASU No. 2016-09 (“ASU 2016-09”), and made an accounting policy election to account for the impact of pre-vesting forfeitures as they occur rather than applying an estimated forfeiture rate, as previously required. The following table presents stock-based compensation expense included in the Company’s Condensed Consolidated Statements of Operations and Comprehensive Loss: Three Months Ended March 31, 2017 2016 Research and development $ 1,730 $ 638 General and administrative 1,570 384 Loss from equity method investment 446 — Total $ 3,746 $ 1,022 Grant-Date Fair Value The Company estimated the fair value of each employee and non-employee stock option award on the grant date using the Black-Scholes option-pricing model based on the following assumptions: Three Months Ended March 31, 2017 2016 Employees: Weighted average expected volatility 73.0 % 77.5 % Expected term (in years) 6.0 6.0 Risk free interest rate 2.2 % 1.5 % Expected dividend yield 0.0 % 0.0 % Non-employees: Weighted average expected volatility 81.0 % n/a Expected term (in years) 10.0 n/a Risk free interest rate 2.4 % n/a Expected dividend yield 0.0 % n/a The fair value of the restricted stock awards was determined based on the fair value of the common shares on the grant date. Non-employee stock options and restricted stock awards are marked-to-market at each reporting period. Share Based Payment Activity Stock Option Awards The following table summarizes stock option activity for employees and non-employees (intrinsic value in thousands): Stock Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Aggregate Intrinsic Value Outstanding at December 31, 2016 4,535,371 $ 8.38 9.1 $ 53,966 Granted 440,032 $ 20.78 Exercised (4,690 ) $ 4.24 Cancelled or forfeited (140,822 ) $ 5.14 Outstanding at March 31, 2017 4,829,891 $ 9.59 9.0 $ 58,960 Exercisable at March 31, 2017 1,289,490 $ 4.27 8.6 $ 22,568 Vested or expected to vest at March 31, 2017 (1) 4,755,902 $ 9.51 9.0 $ 58,417 (1) Represents the number of vested options at March 31, 2017 plus options expected to vest in the future. As of March 31, 2017, total unrecognized compensation expense related to stock options was $28.9 million which the Company expects to recognize over a remaining weighted-average period of 3.2 years. During the three months ended March 31, 2017 and 2016, the Company granted options to purchase 15,000 and 13,333 common shares, respectively, subject to performance-based vesting conditions. As of March 31, 2017, options to purchase 284,372 common shares subject to performance-based vesting conditions were vested, as performance conditions were achieved, and no options to purchase common shares subject to performance-based vesting conditions were deemed probable of vesting. Restricted Stock Awards The following table summarizes restricted stock activity for employees and non-employees during the three months ended March 31, 2017: Reflected as outstanding upon vesting Reflected as outstanding upon grant date Total Weighted- Average Grant Date Fair Value Unvested restricted common shares as of December 31, 2016 89,367 650,856 740,223 $ 3.84 Vested (8,380 ) (106,000 ) (114,380 ) 4.02 Unvested restricted common shares as of March 31, 2017 80,987 544,856 625,843 $ 3.81 During the three months ended March 31, 2017, the total fair value of vested restricted common shares was $2.3 million. As of March 31, 2017, total unrecognized compensation expense related to unvested restricted common shares was $6.4 million which the Company expects to recognize over a remaining weighted-average period of 1.2 years. The Company did not grant any restricted common shares subject to performance-based vesting conditions during the three months ended March 31, 2017. As of March 31, 2017, 50,000 restricted common shares subject to performance-based vesting conditions were vested. During the year ended December 31, 2016, the Company and Fay Corp. transferred 290,400 common shares to a founder, 268,093 of which were subject to vesting conditions with a weighted average grant date fair value of $12.65 per share. The unvested common shares are subject to repurchase by the Company upon termination of the holder’s service relationship with the Company as well as upon certain triggering events such as termination for cause, material breach of agreement and insolvency of the holder. The Company recognized expense related to these common shares in the amount of $0.2 million and $0 during the three months ended March 31, 2017 and 2016, respectively.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes During the three months ended March 31, 2017 and 2016, the Company recorded an income tax provision of $0.3 million and $0.1 million, respectively, representing an effective tax rate of -1.3% and -0.9%, respectively. The income tax provision is primarily attributable to the year-to-date pre-tax income earned by the Company’s U.S. and U.K. subsidiaries. The difference in the statutory tax rate and effective tax rate is primarily a result of the jurisdictional mix of earnings and losses that are not benefited. The Company maintains a valuation allowance against certain deferred tax assets that are not more-likely-than-not realizable. As a result, the Company has not recognized a tax benefit related to the Swiss losses generated in the current periods.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	11. Related Party Transactions The Company is a party to intellectual property license agreements with Dr. Charpentier. As of March 31, 2017 and December 31, 2016, the Company owed Dr. Charpentier approximately $0.2 million and $0.5 million, respectively, of sublicense fees primarily related to the Bayer Agreement. During the three months ended March 31, 2017 and 2016, the Company recorded sublicensing fees of $0 and $0.3 million, respectively, due to Dr. Charpentier in research and development expense related to the Bayer Agreement. The Company is a party to the JV with Bayer HealthCare. During the three months ended March 31, 2017 and 2016, the Company recognized revenue of $1.2 million and $0, respectively, related to the collaboration with Casebia. During the three months ended March 31, 2017, and 2016, the Company recognized $1.1 million and $0 of research and development expense, respectively, related to the performance of services for Casebia. As of March 31, 2017 and December 31, 2016, the Company recorded accounts receivable of $1.1 million and $0.8 million, respectively, other current assets of $0.6 million and $0, respectively, and deferred revenue of $0.4 million and $0.5 million, respectively, related to Casebia.

Summary of Significant Accoun18

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Unaudited Interim Financial Information	Unaudited Interim Financial Information The condensed consolidated financial statements of the Company included herein have been prepared, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted from this report, as is permitted by such rules and regulations. Accordingly, these condensed consolidated financial statements should be read in conjunction with the financial statements and notes thereto included in the Annual Report.
Basis of Presentation and Use of Estimates	Basis of Presentation and Use of Estimates The accompanying condensed consolidated financial statements have been prepared in conformity with GAAP, and include the accounts of (i) the Company, and (ii) its wholly-owned subsidiaries, CRISPR Ltd., CRISPR Inc., and TRACR. All intercompany accounts and transactions have been eliminated. The Company considers events or transactions that occur after the balance sheet date but before the financial statements are issued to provide additional evidence relative to certain estimates or to identify matters that require additional disclosure. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASUs”) of the Financial Accounting Standards Board (“FASB”). The Company accounts for its 50% investment in Casebia Therapeutics LLP (“Casebia”) under the equity method of accounting. See Note 7 for further details. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. On an ongoing basis, the Company’s management evaluates its estimates, which include, but are not limited to, equity-based compensation expense, revenue recognition, equity method investments, and reported amounts of expenses during the period. Significant estimates in these condensed consolidated financial statements have been made in connection with the calculation of revenues, research and development expenses, equity-based compensation expense, fair value of intangible assets, and the provision for or benefit from income taxes. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable under the circumstances. Actual results may differ from those estimates or assumptions.
Net Loss Per Share Attributable to Common Shareholders	Net Loss Per Share Attributable to Common Shareholders Basic net income (loss) per share is calculated by dividing net income (loss) attributable to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted net income per share is calculated by dividing the net income attributable to common shareholders by the weighted-average number of common equivalent shares outstanding for the period, including any dilutive effect from outstanding stock options and warrants using the treasury stock method. The following common share equivalents, presented on an as converted basis, were excluded from the calculation of net loss per share for the periods presented, due to their anti-dilutive effect (in common stock equivalent shares): Three Months Ended March 31, 2017 2016 Convertible preferred shares — 24,301,632 Dr. Emmanuelle Charpentier call option — 328,017 Outstanding options 4,829,891 2,384,908 Unvested unissued restricted common shares 80,987 142,794 Total 4,910,878 27,157,351
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers Revenue from Contracts with Customers Revenue from Contracts with Customers Principal versus Agent Considerations Revenue from Contracts with Customers Identifying Performance Obligations and Licensing Revenue from Contracts with Customers Narrow-Scope Improvements and Practical Expedients The Revenue ASUs noted above provide an accounting standard for a single comprehensive model for use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance. The accounting standard is effective for interim and annual periods beginning after December 15, 2017, with an option to early adopt for interim and annual periods beginning after December 15, 2016. The guidance permits two methods of adoption: retrospectively to each prior reporting period presented (the full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (the modified retrospective method). The Company currently anticipates adopting the new standard effective January 1, 2018 under the full retrospective method. The Company is in the process of determining the impact of the Revenue ASUs on its financial statements as it relates to their two revenue generating collaboration agreements. In February 2016, the FASB issued ASU No. 2016-02, Leases In October 2016, the FASB issued ASU No. 2016-16, Income Taxes Intra-Entity Transfers of Assets Other Than Inventory In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows Restricted Cash In January 2017, the FASB issued ASU No. 2017-01, Business Combinations In January 2017, the FASB issued ASU No. 2017-03, Accounting Changes and Error Corrections and Investments—Equity Method and Joint Ventures Measurement of Credit Losses on Financial Instruments, 606 – Revenue from Contracts with Customers, Leases In January 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other

Summary of Significant Accoun19

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Schedule of Antidilutive Securities Excluded from Computation of Net Loss per Share	The following common share equivalents, presented on an as converted basis, were excluded from the calculation of net loss per share for the periods presented, due to their anti-dilutive effect (in common stock equivalent shares): Three Months Ended March 31, 2017 2016 Convertible preferred shares — 24,301,632 Dr. Emmanuelle Charpentier call option — 328,017 Outstanding options 4,829,891 2,384,908 Unvested unissued restricted common shares 80,987 142,794 Total 4,910,878 27,157,351

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	3 Months Ended
	Mar. 31, 2017
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net, consists of the following (in thousands): As of March 31, December 31, 2017 2016 Computer equipment and software $ 110 $ 110 Furniture, fixtures, and other 2,044 2,044 Laboratory equipment 4,728 2,970 Leasehold improvements 15,765 15,780 Construction work in process 1,165 1,065 23,812 21,969 Accumulated Depreciation (1,647 ) (942 ) Property and equipment, net $ 22,165 $ 21,027

Accrued Expenses (Tables)

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2017
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses consist of the following (in thousands): As of March 31, December 31, Payroll and employee-related costs $ 1,570 $ 2,585 Research costs 490 996 Licensing fees 1,111 492 Professional fees 1,873 2,715 Intellectual property costs 1,700 3,372 Accrued property and equipment 4,697 5,081 Other 258 1,079 Total $ 11,699 $ 16,320

Share Capital (Tables)

Share Capital (Tables)	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Schedule of Conditional Capital Reserved for Future Issuance	The Company had the following conditional capital reserved for future issuance: As of Conditional Capital March 31, 2017 December 31, 2016 Unvested unissued restricted stock 166,667 166,667 Outstanding stock options 4,829,891 4,535,371 Reserved for future issuance under stock option plans 4,996,123 5,290,643 Shares available for bonds and similar debt instruments 4,919,700 4,919,700 Shares available for employee purchase plans 413,226 413,226 Total 15,325,607 15,325,607

Equity-based Compensation (Tabl

Equity-based Compensation (Tables)	3 Months Ended
	Mar. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Stock-Based Compensation Expense	The Company uses the straight-line attribution method to recognize stock-based compensation expense for stock options and restricted stock awards. Stock options and restricted stock awards generally vest over four years with 25% vesting on the first anniversary of service commencement and the remaining 75% vesting monthly thereafter. Effective January 1, 2017, the company adopted ASU No. 2016-09 (“ASU 2016-09”), and made an accounting policy election to account for the impact of pre-vesting forfeitures as they occur rather than applying an estimated forfeiture rate, as previously required. The following table presents stock-based compensation expense included in the Company’s Condensed Consolidated Statements of Operations and Comprehensive Loss: Three Months Ended March 31, 2017 2016 Research and development $ 1,730 $ 638 General and administrative 1,570 384 Loss from equity method investment 446 — Total $ 3,746 $ 1,022
Fair Value of Employee and Non-employee Stock Option Award on the Grant Date Using the Black-Scholes Option-Pricing Model	The Company estimated the fair value of each employee and non-employee stock option award on the grant date using the Black-Scholes option-pricing model based on the following assumptions: Three Months Ended March 31, 2017 2016 Employees: Weighted average expected volatility 73.0 % 77.5 % Expected term (in years) 6.0 6.0 Risk free interest rate 2.2 % 1.5 % Expected dividend yield 0.0 % 0.0 % Non-employees: Weighted average expected volatility 81.0 % n/a Expected term (in years) 10.0 n/a Risk free interest rate 2.4 % n/a Expected dividend yield 0.0 % n/a
Summary of Stock Option Activity for Employees and Non-employees	The following table summarizes stock option activity for employees and non-employees (intrinsic value in thousands): Stock Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Aggregate Intrinsic Value Outstanding at December 31, 2016 4,535,371 $ 8.38 9.1 $ 53,966 Granted 440,032 $ 20.78 Exercised (4,690 ) $ 4.24 Cancelled or forfeited (140,822 ) $ 5.14 Outstanding at March 31, 2017 4,829,891 $ 9.59 9.0 $ 58,960 Exercisable at March 31, 2017 1,289,490 $ 4.27 8.6 $ 22,568 Vested or expected to vest at March 31, 2017 (1) 4,755,902 $ 9.51 9.0 $ 58,417 (1) Represents the number of vested options at March 31, 2017 plus options expected to vest in the future.
Summary of the Company's Restricted Stock Activity	The following table summarizes restricted stock activity for employees and non-employees during the three months ended March 31, 2017: Reflected as outstanding upon vesting Reflected as outstanding upon grant date Total Weighted- Average Grant Date Fair Value Unvested restricted common shares as of December 31, 2016 89,367 650,856 740,223 $ 3.84 Vested (8,380 ) (106,000 ) (114,380 ) 4.02 Unvested restricted common shares as of March 31, 2017 80,987 544,856 625,843 $ 3.81

Organization and Operations - A

Organization and Operations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 24, 2015
Organization and operations [Line Items]
Company formation date	Oct. 28, 2013
Company formation country name	Basel, Switzerland
Accumulated deficit	$ (78,558)	$ (57,083)
Cash	$ 288,872	$ 315,520
CRISPR Therapeutics Limited [Member] | United Kingdom [Member]
Organization and operations [Line Items]
Subsidiary formation date	Feb. 7, 2014
CRISPR Therapeutics, Inc. [Member] | United States [Member]
Organization and operations [Line Items]
Subsidiary formation date	Feb. 16, 2015
TRACR Hematology Limited [Member]
Organization and operations [Line Items]
Formation date, VIE	Jan. 23, 2014
Relationship nature and extent of involvement in VIE	On January 23, 2014, the founders of the Company formed TRACR Hematology Limited (“TRACR”) in the United Kingdom, to further the development of the CRISPR/Cas9 technology into medicines for the treatment of blood-borne illnesses. As the Company was funding and managing TRACR’s operations in 2014, it has been consolidated by the Company from the date that the Company established a variable interest in TRACR in April 2014. In March 2015, the Company acquired 82.1% of the outstanding equity of TRACR in a share exchange transaction. Concurrent with its initial public offering (“IPO”) in October 2016, the Company acquired the outstanding non-controlling interest in TRACR, and as such, as of March 31, 2017, TRACR is a wholly-owned subsidiary of the Company.
Purpose of VIE	To further the development of the CRISPR/Cas9 technology into medicines for the treatment of blood-borne illnesses.
Percentage of outstanding equity acquired			82.10%

Summary of Significant Accoun25

Summary of Significant Accounting Policies - Additional Information (Detail)	Mar. 31, 2017
Casebia Therapeutics LLP [Member]
Summary Of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	50.00%

Summary of Significant Accoun26

Summary of Significant Accounting Policies - Schedule of Antidilutive Securities Excluded from Computation of Net Loss per Share (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share	4,910,878	27,157,351
Convertible Preferred Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share		24,301,632
Dr. Emmanuelle Charpentier Call Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share		328,017
Stock Option Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share	4,829,891	2,384,908
Unvested Unissued Restricted Common Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of net loss per share	80,987	142,794

Property and Equipment, net - S

Property and Equipment, net - Summary of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 23,812	$ 21,969
Accumulated Depreciation	(1,647)	(942)
Property and equipment, net	22,165	21,027
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	110	110
Furniture, Fixtures, and Other [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	2,044	2,044
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	4,728	2,970
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	15,765	15,780
Construction Work in Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 1,165	$ 1,065

Property and Equipment, net - A

Property and Equipment, net - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 0.7	$ 0.1

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accrued Liabilities, Current [Abstract]
Payroll and employee-related costs	$ 1,570	$ 2,585
Research costs	490	996
Licensing fees	1,111	492
Professional fees	1,873	2,715
Intellectual property costs	1,700	3,372
Accrued property and equipment	4,697	5,081
Other	258	1,079
Total	$ 11,699	$ 16,320

Convertible Loans - Additional

Convertible Loans - Additional Information (Detail) - USD ($)	Jan. 29, 2016	Oct. 26, 2015	Mar. 31, 2017	Mar. 31, 2016
Debt Conversion [Line Items]
Borrowings under loan agreement				$ 35,000,000
Conversion of convertible loans to Series B Preferred Shares				61,929,000
Gain on extinguishment of debt				$ 11,482,000
Bayer Convertible Loans [Member]
Debt Conversion [Line Items]
Loan agreement maturity date			Jan. 29, 2016
Borrowings under loan agreement	$ 35,000,000
Loan, accrued interest rate	2.00%
Borrowings under loan agreement	$ 35,000,000
Vertex Convertible Loans [Member]
Debt Conversion [Line Items]
Borrowings under loan agreement		$ 38,200,000
Loan, accrued interest rate		2.50%
Loan agreement maturity date			Apr. 26, 2016
Series B Redeemable Convertible Preferred Shares [Member] | Bayer Convertible Loans [Member]
Debt Conversion [Line Items]
Preferred shares, shares issued upon conversion	2,605,330
Preferred shares, conversion price per share	$ 13.43
Fair value of convertible loan	$ 24,500,000
Allocated to convertible loan	27,000,000
Interest expense	8,000,000
Conversion of convertible loans to Series B Preferred Shares	$ 35,000,000
Series B Redeemable Convertible Preferred Shares [Member] | Vertex Convertible Loans [Member]
Debt Conversion [Line Items]
Preferred shares, shares issued upon conversion	2,859,278
Preferred shares, conversion price per share	$ 13.43
Fair value of convertible loan	$ 26,900,000
Gain on extinguishment of debt	$ 11,500,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017USD ($)Sublease	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)
Contingencies And Commitments [Line Items]
Cost sharing expensed relating to patent maintenance, defense and prosecution, incurred	$ 0.5	$ 0.6
Cost sharing expensed relating to patent maintenance, defense and prosecution, accrued	$ 0.9		$ 2.8
Research and Office Facility [Member]
Contingencies And Commitments [Line Items]
Operating lease number of sublet portions | Sublease	1

Significant Contracts - Additio

Significant Contracts - Additional Information (Detail) € in Millions, SFr in Millions		1 Months Ended		3 Months Ended		12 Months Ended
		Apr. 30, 2014USD ($)	Apr. 30, 2014CHF (SFr)	Mar. 31, 2017USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Nov. 30, 2014EUR (€)	Nov. 30, 2014USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense	[1]			$ 14,805,000	$ 6,012,000
Non-current deferred revenue				$ 78,311,000		$ 77,646,000
Date of joint venture agreement				Dec. 19, 2015
Equity method investment				$ 0		0
Stock-based compensation expense				3,746,000	1,022,000
Casebia Therapeutics LLP [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense				1,100,000	0
Revenue from collaboration agreement				1,200,000	0
Non-current deferred revenue				$ 400,000		500,000
Date of formation of joint venture entity				Feb. 12, 2016
Unrecognized equity method losses in excess of Company's interest				$ 6,500,000		4,000,000
Stock-based compensation expense				500,000	0
Net loss of joint venture				5,500,000	73,800,000
Casebia Therapeutics LLP [Member] | Fair Value of CRISPR License Acquired [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense					71,400,000
Vertex Pharmaceuticals Inc [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense				2,600,000	600,000
Revenue from collaboration agreement				1,500,000	500,000
Non-current deferred revenue				77,900,000		77,100,000
Patent Assignment Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense				0	19,000
Clinical milestone payment payable								€ 0.3	$ 400,000
CRISPR-Charpentier License Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Upfront fees paid for license		$ 100,000	SFr 0.1
Annual payments for consulting agreement				0	0	$ 0	$ 0
Research and development expense				0	300,000
TRACR-Charpentier License Agreement [Member]
Research and Development Arrangement, Contract to Perform for Others [Line Items]
Research and development expense				$ 0	$ 0
[1]	Including the following amounts of research and development expense with a related party, see Note 11:

Share Capital - Additional Info

Share Capital - Additional Information (Detail) - SFr / shares	Mar. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Common stock, shares authorized	40,258,364
Common shares, par value	SFr 0.03	SFr 0.03
Treasury stock, shares	444,873	444,873
Unvested Unissued Restricted Share Awards [Member]
Class of Stock [Line Items]
Unvested unissued restricted common stock	80,987

Share Capital - Schedule of Con

Share Capital - Schedule of Conditional Capital Reserved for Future Issuance (Detail) - shares	Mar. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Conditional capital reserved for future issuance	15,325,607	15,325,607
Employee Purchase Plans [Member]
Class of Stock [Line Items]
Conditional capital reserved for future issuance	413,226	413,226
Bonds and Similar Debt Instruments [Member]
Class of Stock [Line Items]
Conditional capital reserved for future issuance	4,919,700	4,919,700
Unvested Unissued Restricted Stock [Member]
Class of Stock [Line Items]
Conditional capital reserved for future issuance	166,667	166,667
Outstanding Stock Options [Member]
Class of Stock [Line Items]
Conditional capital reserved for future issuance	4,829,891	4,535,371
Stock Option Plan [Member]
Class of Stock [Line Items]
Conditional capital reserved for future issuance	4,996,123	5,290,643

Equity-based Compensation - Equ

Equity-based Compensation - Equity-based Compensation Expense - Additional Information (Detail) - Stock Options and Restricted Stock Awards [Member]	3 Months Ended
	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, options, vesting period	4 years
Share-based Compensation, options, vesting terms	Vest over four years with 25% vesting on the first anniversary of service commencement and the remaining 75% vesting monthly thereafter
Vesting Percentage on First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, options, vesting percentage	25.00%
Vesting Percentage after First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, options, vesting percentage	75.00%

Equity-based Compensation - Sch

Equity-based Compensation - Schedule of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 3,746	$ 1,022
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	1,730	638
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	1,570	$ 384
Loss from Equity Method Investment [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Equity-based compensation expense	$ 446

Equity-based Compensation - Fai

Equity-based Compensation - Fair Value of Employee and Non-employee Stock Option Award on the Grant Date Using the Black-Scholes Option-Pricing Model (Detail)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average expected volatility	73.00%	77.50%
Expected term (in years)	6 years	6 years
Risk free interest rate	2.20%	1.50%
Expected dividend yield	0.00%	0.00%
Non-Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average expected volatility	81.00%
Expected term (in years)	10 years	0 years
Risk free interest rate	2.40%
Expected dividend yield	0.00%

Equity-based Compensation - Sum

Equity-based Compensation - Summary of Stock Option Activity for Employees and Non-employees (Detail) - Employees and Non-employees [Member] - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options, Outstanding, Beginning Balance	4,535,371
Stock Options, Granted	440,032
Stock Options, Exercised	(4,690)
Stock Options, Cancelled or forfeited	(140,822)
Stock Options, Outstanding, Ending Balance	4,829,891	4,535,371
Stock Options, Exercisable	1,289,490
Stock Options, Vested or expected to vest	4,755,902
Weighted-Average Exercise Price, Outstanding, Beginning Balance	$ 8.38
Weighted-Average Exercise Price, Granted	20.78
Weighted-Average Exercise Price, Exercised	4.24
Weighted-Average Exercise Price, Cancelled or forfeited	5.14
Weighted-Average Exercise Price, Outstanding, Ending Balance	9.59	$ 8.38
Weighted-Average Exercise Price, Exercisable	4.27
Weighted-Average Exercise Price, Vested or expected to vest	$ 9.51
Weighted-Average Remaining Contractual Term	9 years	9 years 1 month 6 days
Weighted-Average Remaining Contractual Term, Exercisable	8 years 7 months 6 days
Weighted-Average Remaining Contractual Term, Vested or expected to vest	9 years
Outstanding at December 31, 2016	$ 58,960	$ 53,966
Exercisable at March 31, 2017	22,568
Vested or expected to vest at March 31, 2017 (1)	$ 58,417

Equity-based Compensation - Sha

Equity-based Compensation - Share Based Payment Activity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense	$ 28,900
Equity-based compensation expense not yet recognized, weighted-average service period for recognition	3 years 2 months 12 days
Stock-based compensation expense	$ 3,746	$ 1,022
Founders' [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Average Exercise Price, Vested or expected to vest			$ 12.65
Stock-based compensation expense	$ 200	$ 0
Fay Corp Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation, number of shares issued			290,400
Fay Corp Awards [Member] | Founders' [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Transfer of vested shares			268,093
Performance-Based [Member] | Vesting Percentage on First Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Options, Granted	15,000	13,333
Share-based compensation, options, vested	284,372
Share-based compensation, options, deemed probable of vesting	0
Performance-Based [Member] | Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock, granted	0
Restricted stock, vested	50,000
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity-based compensation expense not yet recognized, weighted-average service period for recognition	1 year 2 months 12 days
Total fair value of vested restricted common shares	$ 2,300
Total unrecognized compensation expenses	$ 6,400
Restricted stock, vested	114,380

Equity-based Compensation - S40

Equity-based Compensation - Summary of the Company's Restricted Stock Activity (Detail) - Restricted Stock Awards [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted common shares, Number of Shares, Beginning Balance	740,223
Unvested restricted common shares, Number of Shares, Vested	(114,380)
Unvested restricted common shares, Number of Shares, Ending Balance	625,843
Unvested restricted common shares, Weighted-Average Grant Date Fair Value, Beginning Balance | $ / shares	$ 3.84
Unvested restricted common shares, Weighted-Average Grant Date Fair Value, Vested | $ / shares	4.02
Unvested restricted common shares, Weighted-Average Grant Date Fair Value, Ending Balance | $ / shares	$ 3.81
Reflected as Outstanding Upon Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted common shares, Number of Shares, Beginning Balance	89,367
Unvested restricted common shares, Number of Shares, Vested	(8,380)
Unvested restricted common shares, Number of Shares, Ending Balance	80,987
Reflected as Outstanding Upon Grant Date [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted common shares, Number of Shares, Beginning Balance	650,856
Unvested restricted common shares, Number of Shares, Vested	(106,000)
Unvested restricted common shares, Number of Shares, Ending Balance	544,856

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income tax provision	$ 279	$ 76
Effective income tax rate	1.30%	0.90%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Related Party Transaction [Line Items]
Research and development expense	[1]	$ 14,805	$ 6,012
Accounts receivable, related party amount, current		1,057		$ 752
Other current assets, related party amount		577		0
Deferred revenue related party amount		420		527
Casebia Therapeutics LLP [Member]
Related Party Transaction [Line Items]
Revenue from collaboration agreement		1,200	0
Research and development expense		1,100	0
Bayer Healthcare LLC [Member]
Related Party Transaction [Line Items]
Sublicense fees payable		200		500
Bayer Healthcare LLC [Member] | Research and Development [Member]
Related Party Transaction [Line Items]
Sublicense fees recorded		0		$ 300
Bayer Healthcare LLC [Member] | Casebia Therapeutics LLP [Member]
Related Party Transaction [Line Items]
Revenue from collaboration agreement		1,200	0
Research and development expense		1,100	0
Accounts receivable, related party amount, current		1,100	800
Other current assets, related party amount		600	0
Deferred revenue related party amount		$ 400	$ 500
[1]	Including the following amounts of research and development expense with a related party, see Note 11: