Xenon Pharmaceuticals (XENE) 10-K 6 Mar 19 2018 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Mar. 01, 2019	Jun. 29, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	Xenon Pharmaceuticals Inc.
Document Type	10-K
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		25,751,266
Entity Public Float			$ 147.5
Amendment Flag	false
Trading Symbol	XENE
Entity Central Index Key	1,582,313
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Well-known Seasoned Issuer	No
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 67,754	$ 20,486
Marketable securities	51,552	23,181
Accounts receivable	256	438
Prepaid expenses and other current assets	1,875	716
Total current assets	121,437	44,821
Prepaid expenses, long-term		230
Property, plant and equipment, net (note 7)	991	1,070
Total assets	122,428	46,121
Current liabilities:
Accounts payable and accrued expenses (note 8)	4,119	3,383
Loan payable, current portion (note 9)		700
Total current liabilities	4,119	4,083
Loan payable, long-term (note 9)	15,014	6,104
Total liabilities	19,133	10,187
Shareholders’ equity:
Preferred shares, without par value; unlimited shares authorized; issued and outstanding: 1,016,000 (December 31, 2017 - nil) (note 10)	7,732
Common shares, without par value; unlimited shares authorized; issued and outstanding: 25,750,721 (December 31, 2017 - 17,998,420) (note 10)	265,923	173,841
Additional paid-in capital	38,515	36,471
Accumulated deficit	(207,885)	(173,388)
Accumulated other comprehensive loss	(990)	(990)
Shareholders' equity	103,295	35,934
Total liabilities and shareholders’ equity	122,428	46,121
Commitments and contingencies (note 13)

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Preferred shares, without par value
Preferred shares, shares authorized	Unlimited	Unlimited
Preferred shares, issued	1,016,000
Preferred shares, outstanding	1,016,000
Common shares, without par value
Common shares, shares authorized	Unlimited	Unlimited
Common shares, Issued	25,750,721	17,998,420
Common shares, Outstanding	25,750,721	17,998,420

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Revenue:
Collaboration revenue (note 12)		$ 311
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 23,634	$ 25,573
General and administrative	8,382	7,313
Buy-out of future milestones and royalties (note 13d)	6,000
Total operating expenses	38,016	32,886
Loss from operations	(38,016)	(32,575)
Other income (expense):
Interest income	1,216	477
Interest expense	(1,394)
Foreign exchange gain (loss)	(701)	1,394
Gain on termination of collaboration agreement (note 12a)	4,398
Net loss and comprehensive loss	(34,497)	(30,704)
Net loss attributable to preferred shareholders	(2,881)
Net loss attributable to common shareholders	$ (31,616)	$ (30,704)
Net loss per common share (note 6):
Basic	$ (1.63)	$ (1.71)
Diluted	$ (1.63)	$ (1.72)
Weighted-average common shares outstanding (note 6):
Basic	19,425,711	17,985,061
Diluted	19,425,711	18,001,759

Consolidated Statement of Share

Consolidated Statement of Shareholders' Equity - USD ($) $ in Thousands		Total		Convertible Preferred Shares [Member]	Common Shares [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	[1]
Balance at Dec. 31, 2016		$ 63,901			$ 173,246	$ 34,326	$ (142,681)	$ (990)
Balance (in Shares) at Dec. 31, 2016					17,930,590
Net loss		(30,704)					(30,704)
Stock-based compensation expense		2,460				2,460
Issued pursuant to exercise of stock options		$ 177			$ 595	(415)	(3)
Issued pursuant to exercise of stock options (in Shares)		71,006	[2]		67,830
Issuance of warrants		$ 100				100
Balance at Dec. 31, 2017		35,934			$ 173,841	36,471	(173,388)	(990)
Balance (in Shares) at Dec. 31, 2017					17,998,420
Net loss		(34,497)					(34,497)
Issuance of common shares,net of issuance costs (note 10a)		102,850			$ 102,850
Issuance of common shares, net of issuance costs (note 10a) (in shares)					9,540,000
Issued (cancelled) pursuant to exchange agreement (note 10d)				$ 21,825	$ (21,825)
Issued (cancelled) pursuant to exchange agreement (note 10d) (in Shares)				2,868,000	(2,868,000)
Conversion of preferred shares to common shares (note 10d)				$ (14,093)	$ 14,093
Conversion of preferred shares to common shares (note 10d) (in shares)				(1,852,000)	1,852,000
Cancelled pursuant to termination of collaboration agreement (note 12a)		(4,470)			$ (4,470)
Cancelled pursuant to termination of collaboration agreement (note 12a) (in Shares)					(1,000,000)
Stock-based compensation expense		$ 2,652				2,652
Issued pursuant to exercise of stock options (in Shares)	[2]	251,163
Issued pursuant to exercise of stock options and warrants		$ 288			$ 1,434	(1,146)
Issued pursuant to exercise of stock options and warrants (in shares)					228,301
Issuance of warrants		538				538
Balance at Dec. 31, 2018		$ 103,295		$ 7,732	$ 265,923	$ 38,515	$ (207,885)	$ (990)
Balance (in Shares) at Dec. 31, 2018				1,016,000	25,750,721
[1]	Our accumulated other comprehensive loss is entirely related to historical cumulative translation adjustments from the application of U.S. dollar reporting when the functional currency of the Company was the Canadian dollar.
[2]	During the year ended December 31, 2018, 49,502 (2017 – 63,425) stock options were exercised for the same number of common shares in exchange for cash. In the same period, the Company issued 106,474 (2017 – 4,405) common shares for the cashless exercise of 201,661 (2017 – 7,581) stock options.

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating activities:
Net loss	$ (34,497)	$ (30,704)
Items not involving cash:
Depreciation	586	649
Amortization of discount on term loan	284	11
Stock-based compensation	2,625	2,236
Unrealized foreign exchange (gain) loss	646	(1,474)
Gain on termination of collaboration agreement (note 12a)	(4,398)
Changes in operating assets and liabilities:
Accounts receivable	175	(232)
Prepaid expenses, and other current assets	(928)	613
Prepaid expenses, long term		178
Accounts payable and accrued expenses	783	(3)
Net cash used in operating activities	(34,724)	(28,726)
Investing activities:
Purchases of property, plant and equipment	(507)	(315)
Purchase of marketable securities	(77,002)	(28,007)
Proceeds from marketable securities	48,522	52,616
Net cash provided by (used in) investing activities	(28,987)	24,294
Financing activities:
Proceeds from issuance of refinanced term loan, net of issuance costs (note 9)	8,453	6,893
Issuance of common shares, net of issuance costs (note 10a)	102,850
Issuance of common shares pursuant to exercise of stock options	288	177
Net cash provided by financing activities	111,591	7,070
Effect of exchange rate changes on cash and cash equivalents	(612)	753
Increase in cash and cash equivalents	47,268	3,391
Cash and cash equivalents, beginning of year	20,486	17,095
Cash and cash equivalents, end of year	67,754	20,486
Supplemental disclosures:
Interest paid	561
Interest received	1,067	740
Supplemental disclosures of non-cash transactions:
Fair value of stock options and warrants exercised on a cashless basis	1,125	$ 25
Issuance of preferred shares in exchange for common shares (note 10d)	21,825
Conversion of preferred shares to common shares (note 10d)	14,093
Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member]
Supplemental disclosures of non-cash transactions:
Termination of Teva agreement through cancellation of common shares (note 12a)	$ 4,470

Nature of the Business

Nature of the Business	12 Months Ended
	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of the business	1. Nature of the business: Xenon Pharmaceuticals Inc. (the “Company”), incorporated in 1996 under the British Columbia Business Corporations Act and continued federally in 2000 under the Canada Business Corporation Act, is a clinical stage biopharmaceutical company focused on developing innovative therapeutics to improve the lives of patients with neurological disorders. Building upon its extensive knowledge of human genetics and diseases caused by mutations in ion channels, known as channelopathies, the Company is advancing a novel product pipeline of neurology-focused therapies to address areas of high unmet medical need, with a focus on epilepsy. The Company has incurred significant operating losses since inception. As of December 31, 2018, the Company had an accumulated deficit of $207,885 and a $34,497 net loss for the year ended December 31, 2018. Management expects to continue to incur significant expenses in excess of revenue and to incur operating losses for the foreseeable future. To date, the Company has financed its operations primarily through funding received from collaboration and license agreements, private placements of common and preferred shares, public offerings of common shares, debt financing, and government funding. Until such time as the Company can generate substantial product revenue, if ever, management expects to finance the Company’s cash needs through a combination of collaboration agreements, equity and debt financings. The continuation of research and development activities and the future commercialization of its products are dependent on the Company’s ability to successfully raise additional funds when needed. It is not possible to predict either the outcome of future research and development programs or the Company’s ability to continue to fund these programs in the future.

Basis of Presentation

Basis of Presentation	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of presentation	2. Basis of presentation: These consolidated financial statements are presented in U.S. dollars and have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”). The Company has one wholly-owned subsidiary as at December 31, 2018, Xenon Pharmaceuticals USA Inc., which was incorporated in Delaware on December 2, 2016. These consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. All intercompany transactions and balances have been eliminated on consolidation.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Significant accounting policies	3. Significant accounting policies: (a) Use of estimates: The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Significant areas of estimates include, but are not limited to, the timing of revenue recognition, the determination of stock-based compensation and the amounts recorded as accrued liabilities. Actual results could differ materially from those estimates. Estimates and assumptions are reviewed quarterly. All revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected. (b) Cash and cash equivalents: Cash equivalents are highly liquid investments that are readily convertible into cash with terms to maturity of three months or less when acquired. Cash equivalents are recorded at cost plus accrued interest. The carrying value of these cash equivalents approximates their fair value. (c) Marketable securities: Marketable securities are investments with original maturities exceeding three months, and have remaining maturities of less than one year. Marketable securities accrue interest based on a fixed interest rate for the term. The carrying value of marketable securities is recorded at cost plus accrued interest, which approximates their fair value. (d) Intellectual Property The costs incurred in establishing and maintaining patents for intellectual property developed internally are expensed in the period incurred. (e) Property, plant and equipment: Property, plant and equipment are stated at cost less accumulated depreciation and/or accumulated impairment losses, if any. Repairs and maintenance costs are expensed in the period incurred. Property, plant and equipment are amortized over their estimated useful lives using the straight-line method based on the following rates: Asset Rate Research equipment 5 years Office furniture and equipment 5 years Computer equipment 3 years Leasehold improvements Over the lesser of lease term or estimated useful life (f) Impairment of long-lived assets: The Company monitors its long-lived assets for indicators of impairment. If such indicators are present, the Company assesses the recoverability of affected assets by determining whether the carrying value of such assets is less than the sum of the undiscounted future cash flows of the assets. If such assets are found not to be recoverable, the Company measures the amount of such impairment by comparing the carrying value of the assets to the fair value of the assets, with the fair value generally determined based on the present value of the expected future cash flows associated with the assets. No impairment of long-lived assets was noted during the years ended December 31, 2018 and 2017. (g) Concentration of credit risk and of significant customers: Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. Cash and cash equivalents were held at major financial institutions in Canada and the United States. Such deposits may be in excess of insured limits in the event of non-performance by the institutions; however, the Company does not anticipate non-performance. (h) Financial instruments and fair value: We measure certain financial instruments and other items at fair value. To determine the fair value, we use the fair value hierarchy for inputs used to measure fair value of financial assets and liabilities. This hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three levels: Level 1 (highest priority), Level 2, and Level 3 (lowest priority). • Level 1 - Unadjusted quoted prices in active markets for identical instruments. • Level 2 - Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (i.e., interest rates, yield curves, etc.), and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs). • Level 3 - Inputs are unobservable and reflect the Company’s assumptions as to what market participants would use in pricing the asset or liability. The Company develops these inputs based on the best information available. Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. Changes in the observability of valuation inputs may result in a reclassification of levels for certain securities within the fair value hierarchy. The Company’s Level 1 assets include cash and cash equivalents and marketable securities with quoted prices in active markets. The carrying amount of accounts receivables, accounts payable and accrued expenses approximates fair value due to the nature and short-term of those instruments. The Company’s term loan bears interest at a rate that approximates prevailing market rates for instruments with similar characteristics and, accordingly, the carrying value of the loan approximates fair value. ( i ) Revenue recognition: The Company recognizes the amount of revenue to which it expects to be entitled, for the transfer of promised goods or services to customers under a five-step model: (i) identify contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as a performance obligation is satisfied. The Company generates revenue primarily through collaboration agreements. Such agreements may require the Company to deliver various rights and/or services, including intellectual property rights or licenses and research and development services. Under such collaboration agreements, the Company is generally eligible to receive non-refundable upfront payments, funding for research and development services, milestone payments, and royalties. In contracts where the Company has more than one performance obligation to provide its customer with goods or services, each performance obligation is evaluated to determine whether it is distinct based on whether (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available and (ii) the good or service is separately identifiable from other promises in the contract. The consideration under the contract is then allocated between the distinct performance obligations based on their respective relative stand-alone selling prices. The estimated stand-alone selling price of each deliverable reflects the Company’s best estimate of what the selling price would be if the deliverable was regularly sold on a stand-alone basis and is determined by reference to market rates for the good or service when sold to others or by using an adjusted market assessment approach if selling price on a stand-alone basis is not available. The consideration allocated to each distinct performance obligation is recognized as revenue when control is transferred to the customer for the related goods or services. Consideration associated with at-risk substantive performance milestones, including sales-based milestones, is recognized as revenue when it is probable that a significant reversal of the cumulative revenue recognized will not occur. Sales-based royalties received in connection with licenses of intellectual property are subject to a specific exception in the revenue standards, whereby the consideration is not included in the transaction price and recognized in revenue until the customer’s subsequent sales or usages occur. (j) Research and development costs: Research and development costs are expensed in the period incurred. Certain development activity costs, such as pre-clinical costs, manufacturing costs and clinical trial costs, are a component of research and development costs and include fees paid to contract research organizations, investigators and other vendors who conduct certain product development activities on behalf of the Company. The amount of expenses recognized in a period related to service agreements is based on estimates of the work performed using the accrual basis of accounting. These estimates are based on patient enrollment, services provided and goods delivered, contractual terms, and experience with similar contracts. The Company monitors these factors and adjusts the estimates accordingly. Payments made to third parties under these arrangements in advance of the receipt of the related services are recorded as prepaid expenses until the services are rendered. (k) Stock-based compensation: The Company grants stock options to employees, directors and officers pursuant to a stock option plan described in note 10c. Employee stock-based compensation expense is measured at the grant date, based on the estimated fair value of the award, and is recognized as an expense, net of actual forfeitures, over the requisite service period with a corresponding increase in additional paid-in capital. Stock-based compensation expense is amortized on a straight-line basis over the requisite service period for the entire award, which is generally the vesting period of the award. Any consideration received on exercise of stock options is credited to share capital. (l) Foreign currency translation: The functional and reporting currency of the Company and its subsidiary is the U.S. dollar. Monetary assets and liabilities denominated in a currency other than the U.S. dollar are re-measured into U.S. dollars at the exchange rate prevailing as at the balance sheet date. Non-monetary assets and liabilities acquired in a currency other than U.S. dollars are translated at historical exchange rates prevailing at each transaction date. Revenue and expense transactions are translated at the exchange rates prevailing at each transaction date. Exchange gains and losses on translation are included in the consolidated statements of operations and comprehensive income (loss) as foreign exchange gain (loss). (m) Income taxes: Deferred income taxes are recognized for the future tax consequences attributable to differences between the carrying amounts of assets and liabilities and their respective tax bases and net operating loss and credit carryforwards. Deferred income tax assets and liabilities are measured at enacted rates expected to apply to taxable income in the years in which those temporary differences and carryforwards are expected to be recovered or settled. The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in the consolidated statement of operations and comprehensive income (loss) in the period that includes the enactment date. A valuation allowance is provided when realization of deferred income tax assets does not meet the more-likely-than-not criterion for recognition. (n) Deferred tenant inducements: Deferred tenant inducements, which include leasehold improvements paid for by the landlord and free rent, are included in the consolidated balance sheet as accounts payable and accrued expenses and recognized as a reduction of rent expense on a straight-line basis over the term of the lease. (o) Segment and geographic information: Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment.

Changes in significant accounti

Changes in significant accounting policies	12 Months Ended
	Dec. 31, 2018
Accounting Changes And Error Corrections [Abstract]
Changes in significant accounting policies	4. Changes in significant accounting policies: The Company adopted the new revenue standard (Accounting Standards Codification “ASC” 606), effective January 1, 2018, using the modified retrospective method under which previously presented financial statements are not restated and the cumulative effect of adopting the new revenue standard on contracts in process is recognized by an adjustment to retained earnings at the effective date. The adoption of the new revenue standard did not change the Company’s recognized revenue under its one ongoing significant collaborative research and license agreement with Genentech, a member of the Roche Group, described in note 12b and no cumulative effect adjustment was required. Refer to the Company’s Revenue Recognition policy described in note 3i.

Future Changes in Accounting Po

Future Changes in Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Changes And Error Corrections [Abstract]
Future changes in accounting policies	5. Future changes in accounting policies: In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842): Recognition and Measurement of Financial Assets and Financial Liabilities. The update requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous U.S. GAAP. The new guidance retains a distinction between finance leases and operating leases, with cash payments from operating leases classified within operating activities in the statement of cash flows. These amendments will be effective for public entities for fiscal years and interim periods within those years, beginning after December 15, 2018. The Company adopted the standard on January 1, 2019 and can elect to record a cumulative-effect adjustment as of the beginning of the year of adoption or apply a modified retrospective transition approach. The Company has identified one operating lease for its premises which will be subject to the new guidance and will be recognized as an operating lease liability and right-of-use asset upon adoption. In November 2018, the FASB issued ASU 2018-18, Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606. These amendments make targeted improvements to accounting for collaborative arrangements by clarifying that certain transactions between collaborative arrangement participants should be accounted for as revenue under Topic 606 when the collaborative arrangement participant is a customer in the context of a unit of account. In those situations, all the guidance in Topic 606 should be applied, including recognition, measurement, presentation, and disclosure requirements. In addition, unit-of-account guidance in Topic 808 was aligned with the guidance in Topic 606 (that is, a distinct good or service) when an entity is assessing whether the collaborative arrangement or a part of the arrangement is within the scope of Topic 606. These amendments will be effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2019 and should be applied retrospectively to the date of initial application of Topic 606. The Company is currently evaluating the new guidance to determine the impact it will have on the Company’s consolidated financial statements.

Net Income (Loss) Per Common Sh

Net Income (Loss) Per Common Share and Preferred Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Net income (loss) per common share and preferred share	6. Net income (loss) per common share and preferred share: Basic net income (loss) per common share is calculated using the two-class method required for participating securities which includes the convertible preferred shares as a separate class. The preferred shares entitle the holders to participate in dividends and in earnings and losses of the Company on an equivalent basis as common shares. Accordingly, undistributed earnings (losses) are allocated to common shares and participating preferred shares based on the weighted-average shares of each class outstanding during the period. The treasury stock method is used to compute the dilutive effect of the Company’s stock options and warrants. Under this method, the incremental number of common shares used in computing diluted net income (loss) per common share is the difference between the number of common shares assumed issued and purchased using assumed proceeds. The if-converted method is used to compute the dilutive effect of the Company’s convertible preferred shares. Under the if-converted method, dividends on the preferred shares, if applicable, are added back to earnings attributable to common shareholders, and the preferred shares and paid-in kind dividends are assumed to have been converted at the share price applicable at the end of the period. The if-converted method is applied only if the effect is dilutive. For the year ended December 31, 2018, all stock options, warrants and convertible preferred shares were anti-dilutive and were excluded from the diluted weighted average common shares outstanding for the period. For the year ended December 31, 2017, 2,172,034 stock options and warrants were excluded from the calculation of diluted net loss per common share as their inclusion would be anti-dilutive. No convertible preferred shares were outstanding for the year ended December 31, 2017. The following is a reconciliation of the numerators and denominators of basic and diluted net loss per common share and preferred share: Year Ended December 31, 2018 2017 Numerator: Common Shares Preferred Shares Common Shares Preferred Shares Allocation of loss used attributed to shareholders: Basic $ (31,616 ) $ (2,881 ) $ (30,704 ) $ — Adjustment for change in fair value of liability classified stock options — — (187 ) — Diluted $ (31,616 ) $ (2,881 ) $ (30,891 ) $ — Denominator: Weighted average number of shares: Basic 19,425,711 1,769,900 17,985,061 — Adjustment for dilutive effect of stock options — — 16,698 — Diluted 19,425,711 1,769,900 18,001,759 — Net loss attributable to shareholders per share - basic $ (1.63 ) $ (1.63 ) $ (1.71 ) $ — Net loss attributable to shareholders per share - diluted $ (1.63 ) $ (1.63 ) $ (1.72 ) $ —

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Property, Plant and Equipment	7. Property, plant and equipment: Property, plant and equipment consisted of the following: December 31, 2018 2017 Research equipment $ 7,313 $ 6,984 Office furniture and equipment 1,046 1,043 Computer equipment 2,461 2,311 Leasehold improvements 6,370 6,370 Less: accumulated depreciation and amortization (16,199 ) (15,638 ) Net book value $ 991 $ 1,070

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	12 Months Ended
	Dec. 31, 2018
Payables And Accruals [Abstract]
Accounts Payable and Accrued Expenses	8. Accounts payable and accrued expenses: Accounts payable and accrued expenses consisted of the following: December 31, 2018 2017 Trade payables $ 665 $ 1,253 Employee compensation, benefits, and related accruals 1,728 1,017 Consulting and contracted research 1,404 817 Professional fees 237 252 Other 85 44 Total $ 4,119 $ 3,383

Term Loan

Term Loan	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Term Loan	9. Term Loan: In December 2017, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with Silicon Valley Bank (the “Bank”) under which the Company was funded an initial tranche of $7,000. In June 2018, the Company entered into a First Loan Modification Amendment (the “Modification”) to the Loan Agreement (together, the “Modified Loan Agreement”), pursuant to which the Bank accelerated the availability of a second tranche of $5,000 which was funded on the date of the Modification. Amounts funded under the Modified Loan Agreement were interest-only until September 30, 2018 or, subject to the achievement of certain clinical milestones (the “Interest-Only Milestone”), March 31, 2019. Following the expiration of the interest-only period, the first tranche was payable in 30 equal monthly installments or, if the Interest-Only Milestone was achieved, 24 equal monthly installments of principal plus interest, maturing on March 31, 2021. The second tranche was payable in 24 equal monthly installments or, if the Interest-Only Milestone was achieved, 18 equal monthly installments of principal plus interest, maturing on September 30, 2020. The interest and payment terms of the third and final tranche, if borrowed, remained unchanged from the Loan Agreement. The Modification did not amend the Loan Agreement’s interest provisions. In August 2018, the Company entered into an Amended and Restated Loan and Security Agreement (the “Amended and Restated Loan Agreement”) with the Bank, pursuant to which the Bank agreed to extend a term loan to the Company with a principal amount of $15,500 (the “Term Loan”). The Term Loan was used to repay in full outstanding borrowings of $12,000 under the Modified Loan Agreement and a payment of $485, which represented the current portion of the final payment fee due under the Modified Loan Agreement, as well as for working capital and other general corporate purposes, including the advancement of the Company’s clinical development programs. The Term Loan accrues interest at a floating per annum rate of 0.5% above the prime rate, which is payable monthly commencing in September 2018. The Term Loan is interest-only until March 31, 2020, followed by 30 equal monthly installments of principal plus interest, maturing on September 1, 2022. In addition, the Company is required to pay a final payment fee of 6.5% of the Term Loan on the date on which the term loan is prepaid, paid or becomes due and payable in full. The Company may prepay all, but not less than all, of the Term Loan subject to a prepayment fee of $295, which represents the deferred portion of the final payment fee due under the Modified Loan Agreement, plus 3.0% if prepaid prior to the first anniversary of the effective date of the Amended and Restated Loan Agreement, 2.0% if prepaid on or after the first anniversary, but prior to the second anniversary, or 1.0%, if prepaid on or after the second anniversary but prior to the maturity date. As security for its obligations under the Amended and Restated Loan Agreement, the Company granted the Bank a first priority security interest on substantially all of the Company’s assets except its intellectual property and subject to certain other exceptions. In connection with the Modification, the number of common shares exercisable pursuant to the warrant issued to the Bank in December 2017 under the Loan Agreement (the “December 2017 Warrant”) December 2017 Warrant December 2017 Warrant allowed December 2017 Warrant December 2017 Warrant In connection with the Amended and Restated Loan Agreement, the Company issued a new warrant to the Bank to purchase 40,000 of the Company’s common shares at a price per common share of $9.79. The relative fair value of the common shares exercisable pursuant to this warrant The debt proceeds were allocated based on the relative fair values of the debt instrument and the warrant instrument. The fair value of the warrant and the closing costs were recorded as debt discounts and are being amortized using the effective interest rate method over the term of the loan. At December 31, 2018, the Company determined the effective interest rate on the Amended and Restated Loan Agreement with the Bank to be 9.53% (2017 - 9.25%). Amortization of the debt discount and accretion of the final payment fee was $284 for the year ended December 31, 2018 (2017 - $11). Interest payments are made monthly. Interest expense was $1,394 and the year ended December 31, 2018 (2017 - $24). The outstanding loan and unamortized debt discount balances as of December 31, 2018 in accordance with the repayment terms under Amended and Restated Loan Agreement are as follows : December 31, 2018 2017 Term loan $ 15,500 $ 7,000 Less: unamortized discount on loan (600 ) (203 ) Less: current portion — (700 ) Accrued portion of final payment fee 114 7 Loan payable, long-term $ 15,014 $ 6,104 Scheduled principal payments on outstanding debt as of December 31, 2018, excluding the final payment fee of $1,008, are as follows: 2019 $ — 2020 5,167 2021 6,200 2022 4,133 Total $ 15,500 The Amended and Restated Loan Agreement contains customary representations and warranties, events of default (including an event of default upon the occurrence of a material impairment on the Bank’s security interest over the collateral, and a material adverse change of the Company) and affirmative and negative covenants, including, among others, covenants that limit or restrict the Company’s ability to incur indebtedness, grant liens, merge or consolidate, dispose of assets, make investments, make acquisitions, enter into certain transactions with affiliates, engage in any new line of business, pay dividends or make distributions, or repurchase stock, in each case subject to certain exceptions. Upon the occurrence and during the continuance of an event of default, a default interest rate will apply that is 5.0% above the otherwise applicable interest rate. The Company is in compliance with these covenants at December 31, 2018.

Share Capital

Share Capital	12 Months Ended
	Dec. 31, 2018
Stockholders Equity Note [Abstract]
Share Capital	10. Share capital: (a) Financing: In May 2018, the Company entered into an at-the-market equity offering sales agreement with Stifel Nicolaus & Company, Incorporated (“Stifel”) to sell common shares of the Company having aggregate gross proceeds of up to $30,000, from time to time, through an “at-the-market” equity offering program under which Stifel would act as sales agent. The Company sold 3,440,000 common shares under the sales agreement for proceeds of approximately $29,200, net of commissions paid, but excluding estimated transaction expenses. In July 2018, the Company entered into an at-the-market equity offering sales agreement with Jefferies LLC (“Jefferies”) and Stifel, to sell common shares of the Company having aggregate gross proceeds of up to $50,000, from time to time, through an “at-the-market” equity offering program under which Jefferies and Stifel would act as sales agent. The Company sold 1,600,000 common shares under the sales agreement for proceeds of approximately $14,820, net of commissions paid, but excluding estimated transaction expenses. In connection with the Company’s entry into the July 2018 sales agreement with Jefferies and Stifel, the May 2018 sales agreement was mutually terminated by the Company and Stifel. In September 2018, the Company entered into an underwriting agreement with Jefferies and Stifel, relating to an underwritten public offering of 4,500,000 common shares sold by the Company at a public offering price of $14.00 per common share. The Company received net proceeds of $59,220, net of underwriting discounts and commissions, but before offering expenses. In connection with the Company’s entry into the September 2018 underwriting agreement with Jefferies and Stifel, the July 2018 sales agreement was mutually terminated by the Company, Jefferies and Stifel. (b) Authorized share capital: The Company’s authorized share capital consists of an unlimited number of common and preferred shares without par value. (c) Stock-based compensation: On June 25, 2014, the shareholders of the Company approved the 2014 Equity Incentive Plan (the “2014 Plan”) which permits the grant of stock-based compensation awards to directors, officers, employees and consultants of the Company. The Company’s pre-existing stock option plan (the “Amended and Restated Stock Option Plan”) was limited to the granting of stock options as equity incentive awards whereas the 2014 Plan also allows for the issuance of restricted shares, restricted share units, share appreciation rights and performance shares. The 2014 Plan replaced the Amended and Restated Stock Option Plan. No further options will be granted under the Company’s Amended and Restated Stock Option Plan. The Amended and Restated Stock Option Plan provided for the grant of options for the purchase of common shares to directors, officers, employees and consultants prior to the Company’s initial public offering (“IPO”). The options granted under the Amended and Restated Stock Option Plan vest on a graduated basis over a four-year period or less and each option’s maximum term is ten years. The Amended and Restated Stock Option Plan will continue to govern the options granted thereunder. Under the 2014 Plan, options granted generally vest on a graduated basis over a The exercise price of the options is determined by the Board but must at least be equal to the fair market value of the common shares on the date of grant. Options may be exercised over a maximum term of As of December 31, 2018, a total of 153,209 stock options remain to be granted under the 2014 Plan. The number of common shares available for issuance under the 2014 Plan was increased by 900,000, effective January 1, 2019, as approved by the Board in accordance with the terms of the 2014 Plan Summary of stock option activity is as follows: Number of Weighted Average Exercise Price Aggregate Options CAD $ U.S. $ Intrinsic Outstanding, December 31, 2016 1,910,823 9.84 7.32 4,464 Granted 620,950 8.69 6.69 Exercised (1) (71,006 ) 3.72 2.86 108 Forfeited, cancelled or expired (120,862 ) 9.06 6.98 Outstanding, December 31, 2017 2,339,905 9.32 7.41 159 Granted 706,600 6.73 5.19 Exercised (1) (251,163 ) 4.57 3.53 1,028 Forfeited, cancelled or expired (123,436 ) 13.61 10.50 Outstanding, December 31, 2018 2,671,906 9.49 6.96 3,483 Exercisable, December 31, 2018 1,566,435 10.70 7.84 2,198 (1) During the year ended December 31, 2018, 49,502 (2017 – 63,425) stock options were exercised for the same number of common shares in exchange for cash. In the same period, the Company issued 106,474 (2017 – 4,405) common shares for the cashless exercise of 201,661 (2017 – 7,581) stock options. The following table summarizes the stock options outstanding and exercisable at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Outstanding Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Options Exercisable Weighted Exercise Price U.S. $ (years) CAD $ U.S. $ CAD $ U.S. $ $1.96 - $2.74 529,675 2.34 3.42 2.51 529,675 3.42 2.51 $2.75 - $4.70 237,188 8.84 4.80 3.52 59,589 4.41 3.23 $4.71 - $5.35 508,050 9.19 6.48 4.75 — — — $5.36 - $7.59 391,469 7.61 9.49 6.96 209,664 9.95 7.30 $7.60 - $8.35 269,354 6.13 10.69 7.84 232,869 10.70 7.84 $8.36 - $8.98 365,052 8.17 11.47 8.41 184,322 11.48 8.42 $8.99 - $18.70 371,118 6.39 22.43 16.45 350,316 22.81 16.72 2,671,906 6.73 9.49 6.96 1,566,435 10.70 7.84 At December 31, 2018, there were 1,566,435 options exercisable with a weighted average remaining contractual life of 5.25 years. A summary of the Company’s non-vested stock option activity and related information for the year ended December 31, 2018 is as follows: Number of Options Weighted Average Grant Date Fair CAD $ USD $ Non-vested, January 1, 2018 900,604 7.12 5.66 Granted 706,600 4.84 3.74 Vested (437,771 ) 8.47 6.54 Forfeited or cancelled (63,962 ) 6.70 5.17 Non-vested, December 31, 2018 1,105,471 5.61 4.11 The aggregate fair value of options vested during the year ended December 31, 2018 was $2,861 (2017 – $2,047 ). The fair value of stock options at the date of grant is estimated using the Black-Scholes option-pricing model which requires multiple subjective inputs. The risk-free interest rate of the options is based on the U.S. Treasury yield curve in effect at the date of grant for a term similar to the expected term of the option. Prior to the Company’s IPO in November 2014, the Company’s shares did not have a readily available market; therefore, the Company lacked company-specific historical and implied volatility information. Consequently, the expected volatility of stock options was estimated based on a combination of the Company’s available historical volatility information and historical volatility analysis of peers that were similar to the Company with respect to industry, stage of life cycle, size, and financial leverage. Expected life assumptions are based on the Company’s historical data. The dividend yield is based on the fact that the Company has never paid cash dividends and has no present intention to pay cash dividends. Forfeitures are recognized as they occur. The weighted-average option pricing assumptions are as follows: Years ended December 31 2018 2017 Average risk-free interest rate 2.79 % 2.35 % Expected volatility 75 % 80 % Average expected term (in years) 7.38 7.37 Expected dividend yield 0.00 % 0.00 % Weighted average fair value of options granted $ 3.74 $ 5.02 Stock-based compensation expense is classified in the consolidated statements of operations and comprehensive income (loss) as follows: Years ended December 31, 2018 2017 Research and development $ 988 $ 985 General and administrative 1,772 1,251 $ 2,760 $ 2,236 As of December 31, 2018, the unrecognized stock-based compensation cost related to the non-vested stock options was $3,919, which is expected to be recognized over a weighted-average period of 2.41 years. (d) Exchange agreement with certain funds affiliated with BVF Partners L.P. (collectively, “BVF”): In March 2018, the Company and BVF entered into an exchange agreement pursuant to which the Company issued to BVF 2,868,000 Series 1 Preferred Shares in exchange for 2,868,000 common shares which were subsequently cancelled by the Company. The Company filed articles of amendment creating an unlimited number of Series 1 Preferred Shares. The Series 1 Preferred Shares are convertible into common shares on a one-for-one basis subject to the holder, together with its affiliates, beneficially owning no more than 9.99% of the total number of common shares issued and outstanding immediately after giving effect to such conversion (the “Beneficial Ownership Limitation”). The holder may reset the Beneficial Ownership Limitation to a higher or lower number, not to exceed 19.99% of the total number of common shares issued and outstanding immediately after giving effect to such conversion, upon providing written notice to the Company which will be effective 61 days after delivery of such notice. Each Series 1 Preferred Share is also convertible into one common share at any time at the Company’s option without payment of additional consideration, provided that prior to any such conversion, the holder, together with its affiliates, beneficially owns less than 5.00% of the total number of common shares issued and outstanding and such conversion will not result in the holder, together with its affiliates, beneficially holding more than 5.00% of the total number of common shares issued and outstanding immediately after giving effect to such conversion. In the event of a change of control, holders of Series 1 Preferred Shares shall be issued one common share for each outstanding Series 1 Preferred Share held immediately prior to the change of control (without regard to the Beneficial Ownership Limitation), and following such conversion, will be entitled to receive the same kind and amount of securities, cash or property that a holder of common shares is entitled to receive in connection with such change of control. The Series 1 Preferred Shares rank equally to the common shares in the event of liquidation, dissolution or winding up or other distribution of the assets of the Company among its shareholders and the holders of the Series 1 Preferred Shares are entitled to vote together with the common shares on an as-converted basis and as a single class, subject in the case of each holder of the Series 1 Preferred Shares to the Beneficial Ownership Limitation. Any Series 1 Preferred Shares that are ineligible to be converted into common shares due to the Beneficial Ownership Limitation, measured as of a given record date that applies for a shareholder meeting or ability to act by written consent, shall be deemed to be non-voting securities of the Company. Holders of Series 1 Preferred Shares are entitled to receive dividends (without regard to the Beneficial Ownership Limitation) on the same basis as the holders of common shares. The Company may not redeem the Series 1 Preferred Shares. The Company recorded the issuance of Series 1 Preferred Shares and corresponding cancellation of common shares at $7.61 per share, the estimated weighted average cost at which BVF acquired the common shares. The Series 1 Preferred Shares are recorded wholly as equity under ASC 480, with no bifurcation of conversion feature from the host contract, given that the Series 1 Preferred Shares cannot be cash settled and have no redemption features. During the year ended December 31, 2018, BVF converted 1,852,000 Series 1 Preferred Shares in exchange for an equal number of common shares of the Company.

Concentrations of Market Risk

Concentrations of Market Risk	12 Months Ended
	Dec. 31, 2018
Risks And Uncertainties [Abstract]
Concentration of market risk	11. Concentrations of market risk: (a) Foreign currency risk: At December 31, 2018, the Company had U.S. dollar denominated cash and cash equivalents and marketable securities of $110,771 (2017 - $28,028) and Canadian denominated cash and cash equivalents and marketable securities of CAD$11,644 (2017 - CAD$19,619). The Company faces foreign currency exchange rate risk in part, as a result of entering into transactions denominated in currencies other than U.S. dollars, particularly those denominated in Canadian dollars. The Company also holds non-U.S. dollar denominated cash and cash equivalents, marketable securities, accounts receivable and accounts payable, which are denominated in Canadian dollars Changes in foreign currency exchange rates can create significant foreign exchange gains or losses to the Company. The Company’s current foreign currency risk is with the Canadian dollar, as a majority of non-U.S. dollar denominated expenses are denominated in Canadian dollars and a portion of cash and cash equivalents and marketable securities are held in Canadian dollars. The Company does not currently hedge its exposure and thus assumes the risk of future gains or losses on the amounts of Canadian dollars held . (b) Interest Rate Risk: At December 31, 2018, the Company had cash and cash equivalents and marketable securities of $119,306. The Company’s interest rate risk is primarily attributable to its cash and cash equivalents and marketable securities. The Company believes that it does not have any material exposure to changes in the fair value of these assets as a result of changes in interest rates due to the short term nature of cash and cash equivalents and marketable securities. The Company does not enter into investments for trading or speculative purposes and has not used any derivative financial instruments to manage interest rate exposure. The Company had a total outstanding loan balance of $15,500 as of December 31, 2018, of which $nil was due within 12 months. The interest rate on borrowings under the Amended and Restated Loan Agreement with the Bank accrues at a floating per annum rate of 0.5% above the prime rate.

Collaboration Agreements

Collaboration Agreements	12 Months Ended
	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaboration agreements	12. Collaboration agreements: The Company has entered into a number of collaboration agreements under which it may have received non-refundable upfront payments. Each arrangement is assessed in accordance with ASC 606 under the five-step model as described in note 3i. The Company generally recognizes revenue from non-refundable upfront payments ratably over the estimated term of the performance obligation or period in which the underlying benefit is transferred to the customer. If non-refundable license fees have values to the customer on a standalone basis, separate from the undelivered performance obligations, they are recognized upon delivery. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Research and development milestones in the Company’s collaboration agreements may include the following types of events: • completion of pre-clinical research and development work leading to selection of product candidates; • initiation of Phase 1, Phase 2 or Phase 3 clinical trials; and • achievement of certain other scientific or development events. Regulatory milestone payments may include the following types of events: • filing of regulatory applications for marketing approval in the U.S., Europe or Japan, including investigational new drug applications and new drug applications; and • marketing approval in a major market, such as the U.S., Europe or Japan. Commercialization milestone payments may include payments triggered by annual product sales that achieve pre-specified thresholds. The Company evaluates each arrangement that includes research and development and sales-based milestone payments to determine whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company are not considered probable of being achieved and the transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company re-evaluates the probability of achievement of such milestones, and if necessary, adjusts its estimate of the overall transaction price. (a) Teva Pharmaceutical Industries Ltd. (“Teva Pharmaceutical”) collaborative development and license agreement: In December 2012, the Company entered into a collaborative development and license agreement with Teva Pharmaceutical, through its subsidiary, Ivax International GmbH, pursuant to which the Company granted Teva Pharmaceutical an exclusive worldwide license to develop and commercialize certain products, including TV-45070 (formerly XEN402). In the year ended December 31, 2018, no revenue has been recognized with respect to this agreement (2017 - $59). In March 2018, the Company and , entered into a termination agreement terminating by mutual agreement the collaborative development and license agreement. In connection with the termination, Teva returned and the Company cancelled 1,000,000 common shares that were owned by Teva. Pursuant to the terms of the termination agreement, Teva has also returned, licensed or assigned to the Company certain intellectual property, including certain patent rights and transferred regulatory filings related to TV-45070 to the Company. The termination agreement requires the Company to pay a low single-digit percentage royalty to Teva based on net sales of approved products, if any, resulting from any continued development and commercialization of TV-45070 by the Company or a sublicensee during the period that assigned or licensed patents cover such products. To date, no such sales have occurred. The Company recorded a gain on the termination of the collaboration agreement of $4,398, net of direct costs incurred in connection with the termination and cancellation of 1,000,000 common shares, based on the estimated fair value represented by the market price of the common shares prior to the closing of the transaction. (b) Genentech collaborative research and license agreement: In December 2011, the Company entered into a collaborative research and license agreement with Genentech and its affiliate, F. Hoffman-La Roche Ltd. to discover and develop selective oral inhibitors of Nav1.7 for the treatment of pain. Pursuant to this agreement, the Company granted Genentech a worldwide exclusive license to develop and commercialize compounds directed to Nav1.7 and products incorporating such compounds for all uses. The Company also granted Genentech a worldwide non-exclusive license to diagnostic products for the purpose of developing or commercializing such compounds. Under the terms of the agreement, Genentech paid the Company an upfront fee of $10,000. Genentech also provided funding to the Company for certain of the Company’s full-time equivalents performing the research collaboration plan, which concluded in December 2016. The Company received and recorded a $5,000 milestone payment in 2013 for the selection of a compound for development and an $8,000 payment in 2014 upon the approval by Health Canada of the clinical trial application. No additional milestone payments or royalties have been received to date. The Company is eligible to receive pre-commercial and commercial milestone payments with respect to the licensed products totaling up to an additional $613,000, comprised of up to $45,500 in pre-clinical and clinical milestone payments, up to $387,500 in regulatory milestone payments, and up to $180,000 in sales-based milestone payments for multiple products and indications. In addition, the Company is eligible to receive royalties based on net sales of the licensed products, which range from a mid single-digit percentage to ten percent for small-molecule inhibitors for the timeframe that such products are covered by the licensed patents and a low single-digit percentage thereafter until the date that is ten years after first commercial sale on a country-by-country basis for a period of ten years from first commercial sale on a country-by-country basis At execution of the collaborative research and license agreement with Genentech, the transaction price included only the $10,000 upfront consideration received. None of the at-risk substantive performance milestones, including research and development and sales-based milestones, were included in the transaction price, as all milestone amounts are outside the control of the Company and contingent upon Genentech’s efforts and success in future clinical trials. Consideration associated with at-risk substantive performance milestones is recognized when it is probable that a significant reversal of the cumulative revenue recognized will not occur. Any consideration related to sales-based royalties will be recognized when the related sales occur as they were determined to relate predominantly to the license granted to Genentech and therefore have also been excluded from the transaction price. The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The collaborative research and license agreement with Genentech was amended multiple times, in May 2015, November 2015, March 2016, May 2017, July 2018 and September 2018, to either extend the term of the research program or to provide the Company with greater flexibility in developing compounds that target Nav1.6. Pursuant to the current amendment, the Company obtained a non-exclusive, irrevocable, perpetual, world-wide, sublicensable license under the know-how forming part of the Genentech intellectual property developed under the Nav1.7 collaboration that is necessary or useful to make, use, sell, offer for sale, and import compounds from the Company’s Nav1.6 program that are above a certain potency threshold on Nav1.7 and products containing those compounds. The Company’s license from Genentech includes commercialization rights but we are restricted from developing or commercializing the Company’s Nav1.6 compounds below a certain potency threshold on Nav1.7 in the field of epilepsy and any of the Company’s Nav1.6 compounds, regardless of their potency on Nav1.7, in the field of pain. In exchange for the rights granted to the Company under this amendment, Genentech is eligible to receive a low single-digit percentage, tiered royalty on net sales of the Company’s Nav1.6 compounds, including XEN901, for a period of ten years from first commercial sale on a country-by-country basis. Pursuant to the amendment, Genentech was granted a royalty-free, non-exclusive, world-wide license under the Company’s Nav1.6 intellectual property to make, use, sell, offer for sale and import compounds below a certain potency threshold on Nav1.7 and products containing those compounds for all uses and indications except epilepsy. In March 2014, the Company entered into a new agreement with Genentech for pain genetics, which focused on identifying genetic targets associated with rare phenotypes where individuals have an inability to perceive pain or where individuals have non-precipitated spontaneous severe pain. Pursuant to the terms of this agreement, any intellectual property arising out of the collaboration is jointly owned by the Company and Genentech. The Company also granted Genentech a time-limited, exclusive right of first negotiation on a target-by-target basis to form joint drug discovery collaborations. Under the terms of this agreement, Genentech paid an upfront payment of $1,500 and two $250 milestone payments related to the identification of novel pain targets in September 2015 and July 2017. Genentech’s time-limited, exclusive right of first negotiation, which was exercisable throughout the research term, expired at the same time as the agreement in March 2018. Despite such termination, the Company remains eligible for up to an additional $1,500 in milestone payments. Pursuant to the terms of the Company’s agreement with the Memorial University of Newfoundland, the Company must pay to the Memorial University of Newfoundland certain milestone payments, a single-digit percentage of net sales for pain products the Company sells directly and a single-digit percentage of royalties received for sales of pain products by Genentech.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	13. Commitments and contingencies: (a) Lease commitments: The Company entered into an amended lease agreement for research laboratories and office space in Burnaby, British Columbia, Canada for a 120-month term from April 1, 2012 to March 31, 2022, which included an element of free rent and tenant inducement that is amortized over the term of the lease. Lease expense for the year ended December 31, 2018 was $1,194 (2017 – $1,079 ). Future minimum annual lease payments under existing operating lease commitments are as follows: Year ending December 31: 2019 1,128 2020 1,130 2021 1,069 2022 256 Total $ 3,583 (b) Priority access agreement with Medpace Inc. (“Medpace”): In August 2015, the Company entered into a priority access agreement with Medpace for the provision of certain clinical development services. Under the terms of the agreement, the Company has committed to using Medpace non-exclusively for clinical development services over the five year term of the agreement. In consideration for priority access to Medpace resources and preferred service rates, the Company has committed to $7,000 of services over the term of the agreement, $3,000 of which was paid in the year ended December 31, 2015. (c) License, manufacture and supply agreement: In March 2017, the Company entered into a license, manufacture and supply agreement with a pharmaceutical contract manufacturing organization for the access and use of certain regulatory documents as well as for the manufacture and supply of clinical and commercial drug product to support the development of XEN007 (d) Asset purchase agreement with 1st Order Pharmaceuticals, Inc. (“1st Order”): In April 2017, the Company acquired (previously known as 1OP2198) from 1st Order pursuant to an asset purchase agreement. 1st Order previously acquired 1OP2198 from Valeant Pharmaceuticals Luxembourg S.a.r.l., an indirect subsidiary of Bausch Health Companies Inc. (together with Valeant Pharmaceuticals Ireland Limited, “Bausch Health”) and the Company has assumed certain financial responsibilities under that agreement. Under the terms of the agreement, the Company paid an upfront fee of $350 and milestone payments in 2017 totaling $700, which were expensed as research and development. In September 2018, the Company entered into a milestone and royalty buy-out agreement with Bausch Health under which all potential clinical development, regulatory and sales-based milestones and royalties on commercial sales with respect to XEN1101 that may become owed to Bausch Health under the asset purchase agreement were terminated in exchange for a one-time payment of $6,000 which was expensed in the period. Future potential payments to 1st Order include $500 in clinical development milestones, up to $6,000 in regulatory milestones, and $1,500 in other milestones, which may be payable pre-commercially. There are no royalty obligations to 1st (e) License agreement: In July 2017, the Company entered into a license agreement with a pharmaceutical company for the access and use of certain regulatory documents to support the development of XEN007. Under the terms of the agreement, the Company paid an upfront fee of $1,000, which was expensed as research and development. Future potential payments include $2,000 in clinical development milestones, up to $7,000 in regulatory milestones, plus a low-to-mid single-digit percentage royalty on net sales of any products developed and commercialized under the agreement. (f) Guarantees and indemnifications: The Company has entered into license and research agreements with third parties that include indemnification provisions that are customary in the industry. These indemnification provisions generally require the Company to compensate the other party for certain damages and costs incurred as a result of third party claims or damages arising from these transactions. The maximum amount of potential future indemnification is unlimited; however, the Company currently holds commercial and product liability insurance. This insurance limits the Company’s exposure and may enable it to recover a portion of any future amounts paid. Historically, the Company has not made any indemnification payments under such agreements and the Company believes that the fair value of these indemnification obligations is minimal. Accordingly, the Company has not recognized any liabilities relating to these obligations for any period presented.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	14. Income taxes: Income tax (recovery) expense varies from the amounts that would be computed by applying the expected Canadian and provincial statutory income tax rate of 27% (2017 – 27% ) to loss before income taxes as shown in the following table: 2018 2017 Computed recoveries at Canadian federal and provincial tax rates $ (9,273 ) $ (8,000 ) Change in valuation allowance 10,472 9,210 Investment tax credits earned (1,567 ) (1,393 ) Tax attributes expired/utilized 911 683 Non-deductible expenditures (473 ) 594 Effect of tax rate increases — (1,444 ) Other (70 ) 350 Income tax (recovery) expense $ — $ — Deferred income tax assets and liabilities result from the temporary differences between the amount of assets and liabilities recognized for financial statement and income tax purposes. The significant components of the Company’s net deferred income tax assets are as follows: 2018 2017 Deferred income tax assets Scientific research and experimental development pool $ 26,572 $ 25,056 Investment tax credits 23,808 22,872 Non-capital losses 22,035 13,645 Depreciable assets 5,710 5,360 Deferred financing fees 1,303 578 Other 98 114 Less - valuation allowance (79,526 ) (67,625 ) Net deferred income tax assets $ — $ — The realization of deferred income tax assets is dependent upon the generation of sufficient taxable income during future periods in which the temporary differences are expected to reverse. The valuation allowance is reviewed on a quarterly basis and if the assessment of the “more likely than not” criteria changes, the valuation allowance is adjusted accordingly. A full valuation allowance continues to be applied against deferred income tax assets as the Company has assessed that the realization of such assets does not meet the “more likely than not” criteria. At December 31, 2018, the Company has unclaimed tax deductions for scientific research and experimental development expenditures of $98,412 (2017 – $92,799) with no expiry. At December 31, 2018, the Company has $22,253 (2017 – $21,066) of investment tax credits available to offset federal taxes payable and $7,640 (2017 – $7,560) of provincial tax credits available to offset provincial taxes payable in the future. At December 31, 2018, the Company has non-capital losses, net of uncertain tax positions, carried forward for tax purposes, which are available to reduce taxable income of future years of approximately $81,611 (2017 – $50,536). The investment tax credits and loss carry forwards expire over various years to 2038. As of December 31, 2018, the total amount of the Company’s unrecognized tax benefits of uncertain tax positions were $6,350 (2017 – $6,350). If recognized in future periods, the unrecognized tax benefits would affect the Company’s effective tax rate. The Company recognizes potential accrued interest and penalties related to unrecognized tax benefits within the income tax provision. Interest and penalties have not been accrued at December 31, 2018 as none would be owing on the unrecognized tax benefits due to the availability of non-capital losses to shelter any potential taxable income arising thereon. The Company does not currently expect any significant increases or decreases to these unrecognized tax benefits within 12 months of the reporting date. The Company files income tax returns in Canada and the United States, the jurisdictions in which the Company believes that it is subject to tax. In jurisdictions in which the Company does not believe it is subject to tax and therefore does not file income tax returns, the Company can provide no certainty that tax authorities in those jurisdictions will not subject one or more tax years (since the inception of the Company) to examination. Further, while the statute of limitations in each jurisdiction where an income tax return has been filed generally limits the examination period, as a result of loss carry-forwards, the limitation period for examination generally does not expire until several years after the loss carry-forwards are utilized. Other than routine audits by tax authorities for tax credits and tax refunds that the Company claims, the Company is not aware of any other material income tax examination currently in progress by any taxing jurisdiction. Tax years ranging from 2002 to 2017 remain subject to Canadian income tax examinations.

Related Parties

Related Parties	12 Months Ended
	Dec. 31, 2018
Related Party Transactions [Abstract]
Related Parties	15. Related Parties: ( a) Exchange agreement with BVF: In March 2018, the Company and BVF entered into an exchange agreement pursuant to which the Company issued 2,868,000 Series 1 Preferred Shares in exchange for 2,868,000 common shares which were subsequently cancelled by the Company. Prior to the closing of the transactions contemplated in the exchange agreement, BVF held a number of common shares representing approximately 19.9% of the Company’s then outstanding common shares. For additional information regarding the Series 1 Preferred Shares, refer to note 10d. (b) Termination of collaboration agreement with Teva: In March 2018, the Company and Teva, entered into a termination agreement terminating by mutual agreement the collaborative development and license agreement dated December 7, 2012, as amended. In connection with the termination, the Company cancelled 1,000,000 common shares that were owned by Teva. Prior to the share cancellation, Teva owned more than 5% of the Company’s outstanding common shares. For additional information regarding the termination agreement and the share cancellation, refer to note 12a .

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Use of estimates	(a) Use of estimates: The preparation of the consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Significant areas of estimates include, but are not limited to, the timing of revenue recognition, the determination of stock-based compensation and the amounts recorded as accrued liabilities. Actual results could differ materially from those estimates. Estimates and assumptions are reviewed quarterly. All revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected.
Cash and cash equivalents	(b) Cash and cash equivalents: Cash equivalents are highly liquid investments that are readily convertible into cash with terms to maturity of three months or less when acquired. Cash equivalents are recorded at cost plus accrued interest. The carrying value of these cash equivalents approximates their fair value.
Marketable Securities	(c) Marketable securities: Marketable securities are investments with original maturities exceeding three months, and have remaining maturities of less than one year. Marketable securities accrue interest based on a fixed interest rate for the term. The carrying value of marketable securities is recorded at cost plus accrued interest, which approximates their fair value.
Intellectual Property	(d) Intellectual Property The costs incurred in establishing and maintaining patents for intellectual property developed internally are expensed in the period incurred.
Property, plant and equipment	(e) Property, plant and equipment: Property, plant and equipment are stated at cost less accumulated depreciation and/or accumulated impairment losses, if any. Repairs and maintenance costs are expensed in the period incurred. Property, plant and equipment are amortized over their estimated useful lives using the straight-line method based on the following rates: Asset Rate Research equipment 5 years Office furniture and equipment 5 years Computer equipment 3 years Leasehold improvements Over the lesser of lease term or estimated useful life
Impairment of long-lived assets	(f) Impairment of long-lived assets: The Company monitors its long-lived assets for indicators of impairment. If such indicators are present, the Company assesses the recoverability of affected assets by determining whether the carrying value of such assets is less than the sum of the undiscounted future cash flows of the assets. If such assets are found not to be recoverable, the Company measures the amount of such impairment by comparing the carrying value of the assets to the fair value of the assets, with the fair value generally determined based on the present value of the expected future cash flows associated with the assets. No impairment of long-lived assets was noted during the years ended December 31, 2018 and 2017.
Concentration of credit risk and of significant customers	(g) Concentration of credit risk and of significant customers: Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. Cash and cash equivalents were held at major financial institutions in Canada and the United States. Such deposits may be in excess of insured limits in the event of non-performance by the institutions; however, the Company does not anticipate non-performance.
Financial instruments and fair value	(h) Financial instruments and fair value: We measure certain financial instruments and other items at fair value. To determine the fair value, we use the fair value hierarchy for inputs used to measure fair value of financial assets and liabilities. This hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three levels: Level 1 (highest priority), Level 2, and Level 3 (lowest priority). • Level 1 - Unadjusted quoted prices in active markets for identical instruments. • Level 2 - Inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (i.e., interest rates, yield curves, etc.), and inputs that are derived principally from or corroborated by observable market data by correlation or other means (market corroborated inputs). • Level 3 - Inputs are unobservable and reflect the Company’s assumptions as to what market participants would use in pricing the asset or liability. The Company develops these inputs based on the best information available. Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. Changes in the observability of valuation inputs may result in a reclassification of levels for certain securities within the fair value hierarchy. The Company’s Level 1 assets include cash and cash equivalents and marketable securities with quoted prices in active markets. The carrying amount of accounts receivables, accounts payable and accrued expenses approximates fair value due to the nature and short-term of those instruments. The Company’s term loan bears interest at a rate that approximates prevailing market rates for instruments with similar characteristics and, accordingly, the carrying value of the loan approximates fair value.
Revenue recognition	( i ) Revenue recognition: The Company recognizes the amount of revenue to which it expects to be entitled, for the transfer of promised goods or services to customers under a five-step model: (i) identify contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as a performance obligation is satisfied. The Company generates revenue primarily through collaboration agreements. Such agreements may require the Company to deliver various rights and/or services, including intellectual property rights or licenses and research and development services. Under such collaboration agreements, the Company is generally eligible to receive non-refundable upfront payments, funding for research and development services, milestone payments, and royalties. In contracts where the Company has more than one performance obligation to provide its customer with goods or services, each performance obligation is evaluated to determine whether it is distinct based on whether (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available and (ii) the good or service is separately identifiable from other promises in the contract. The consideration under the contract is then allocated between the distinct performance obligations based on their respective relative stand-alone selling prices. The estimated stand-alone selling price of each deliverable reflects the Company’s best estimate of what the selling price would be if the deliverable was regularly sold on a stand-alone basis and is determined by reference to market rates for the good or service when sold to others or by using an adjusted market assessment approach if selling price on a stand-alone basis is not available. The consideration allocated to each distinct performance obligation is recognized as revenue when control is transferred to the customer for the related goods or services. Consideration associated with at-risk substantive performance milestones, including sales-based milestones, is recognized as revenue when it is probable that a significant reversal of the cumulative revenue recognized will not occur. Sales-based royalties received in connection with licenses of intellectual property are subject to a specific exception in the revenue standards, whereby the consideration is not included in the transaction price and recognized in revenue until the customer’s subsequent sales or usages occur.
Research and development costs	(j) Research and development costs: Research and development costs are expensed in the period incurred. Certain development activity costs, such as pre-clinical costs, manufacturing costs and clinical trial costs, are a component of research and development costs and include fees paid to contract research organizations, investigators and other vendors who conduct certain product development activities on behalf of the Company. The amount of expenses recognized in a period related to service agreements is based on estimates of the work performed using the accrual basis of accounting. These estimates are based on patient enrollment, services provided and goods delivered, contractual terms, and experience with similar contracts. The Company monitors these factors and adjusts the estimates accordingly. Payments made to third parties under these arrangements in advance of the receipt of the related services are recorded as prepaid expenses until the services are rendered.
Stock-based compensation	(k) Stock-based compensation: The Company grants stock options to employees, directors and officers pursuant to a stock option plan described in note 10c. Employee stock-based compensation expense is measured at the grant date, based on the estimated fair value of the award, and is recognized as an expense, net of actual forfeitures, over the requisite service period with a corresponding increase in additional paid-in capital. Stock-based compensation expense is amortized on a straight-line basis over the requisite service period for the entire award, which is generally the vesting period of the award. Any consideration received on exercise of stock options is credited to share capital.
Foreign currency translation	(l) Foreign currency translation: The functional and reporting currency of the Company and its subsidiary is the U.S. dollar. Monetary assets and liabilities denominated in a currency other than the U.S. dollar are re-measured into U.S. dollars at the exchange rate prevailing as at the balance sheet date. Non-monetary assets and liabilities acquired in a currency other than U.S. dollars are translated at historical exchange rates prevailing at each transaction date. Revenue and expense transactions are translated at the exchange rates prevailing at each transaction date. Exchange gains and losses on translation are included in the consolidated statements of operations and comprehensive income (loss) as foreign exchange gain (loss).
Income taxes	(m) Income taxes: Deferred income taxes are recognized for the future tax consequences attributable to differences between the carrying amounts of assets and liabilities and their respective tax bases and net operating loss and credit carryforwards. Deferred income tax assets and liabilities are measured at enacted rates expected to apply to taxable income in the years in which those temporary differences and carryforwards are expected to be recovered or settled. The effect on deferred income tax assets and liabilities of a change in tax rates is recognized in the consolidated statement of operations and comprehensive income (loss) in the period that includes the enactment date. A valuation allowance is provided when realization of deferred income tax assets does not meet the more-likely-than-not criterion for recognition.
Deferred tenant inducements	(n) Deferred tenant inducements: Deferred tenant inducements, which include leasehold improvements paid for by the landlord and free rent, are included in the consolidated balance sheet as accounts payable and accrued expenses and recognized as a reduction of rent expense on a straight-line basis over the term of the lease.
Segment and geographic information	(o) Segment and geographic information: Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one operating segment.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Property Plant and Equipment Estimated Useful Lives	Property, plant and equipment are amortized over their estimated useful lives using the straight-line method based on the following rates: Asset Rate Research equipment 5 years Office furniture and equipment 5 years Computer equipment 3 years Leasehold improvements Over the lesser of lease term or estimated useful life

Net Income (Loss) Per Common _2

Net Income (Loss) Per Common Share and Preferred Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Reconciliation of Numerators and Denominators of Basic and Diluted Net Loss Per Common Share and Preferred Share	The following is a reconciliation of the numerators and denominators of basic and diluted net loss per common share and preferred share: Year Ended December 31, 2018 2017 Numerator: Common Shares Preferred Shares Common Shares Preferred Shares Allocation of loss used attributed to shareholders: Basic $ (31,616 ) $ (2,881 ) $ (30,704 ) $ — Adjustment for change in fair value of liability classified stock options — — (187 ) — Diluted $ (31,616 ) $ (2,881 ) $ (30,891 ) $ — Denominator: Weighted average number of shares: Basic 19,425,711 1,769,900 17,985,061 — Adjustment for dilutive effect of stock options — — 16,698 — Diluted 19,425,711 1,769,900 18,001,759 — Net loss attributable to shareholders per share - basic $ (1.63 ) $ (1.63 ) $ (1.71 ) $ — Net loss attributable to shareholders per share - diluted $ (1.63 ) $ (1.63 ) $ (1.72 ) $ —

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2018
Property Plant And Equipment [Abstract]
Summary of Property, Plant and Equipment	Property, plant and equipment consisted of the following: December 31, 2018 2017 Research equipment $ 7,313 $ 6,984 Office furniture and equipment 1,046 1,043 Computer equipment 2,461 2,311 Leasehold improvements 6,370 6,370 Less: accumulated depreciation and amortization (16,199 ) (15,638 ) Net book value $ 991 $ 1,070

Accounts Payable and Accrued _2

Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2018
Payables And Accruals [Abstract]
Accounts Payable and Accrued Expenses	Accounts payable and accrued expenses consisted of the following: December 31, 2018 2017 Trade payables $ 665 $ 1,253 Employee compensation, benefits, and related accruals 1,728 1,017 Consulting and contracted research 1,404 817 Professional fees 237 252 Other 85 44 Total $ 4,119 $ 3,383

Term Loan (Tables)

Term Loan (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Schedule of Outstanding Loan and Unamortized Debt Discount Balances	The outstanding loan and unamortized debt discount balances as of December 31, 2018 in accordance with the repayment terms under Amended and Restated Loan Agreement are as follows : December 31, 2018 2017 Term loan $ 15,500 $ 7,000 Less: unamortized discount on loan (600 ) (203 ) Less: current portion — (700 ) Accrued portion of final payment fee 114 7 Loan payable, long-term $ 15,014 $ 6,104
Schedule of Principal Payments on Outstanding Debt	Scheduled principal payments on outstanding debt as of December 31, 2018, excluding the final payment fee of $1,008, are as follows: 2019 $ — 2020 5,167 2021 6,200 2022 4,133 Total $ 15,500

Share Capital (Tables)

Share Capital (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Option Activity	Summary of stock option activity is as follows: Number of Weighted Average Exercise Price Aggregate Options CAD $ U.S. $ Intrinsic Outstanding, December 31, 2016 1,910,823 9.84 7.32 4,464 Granted 620,950 8.69 6.69 Exercised (1) (71,006 ) 3.72 2.86 108 Forfeited, cancelled or expired (120,862 ) 9.06 6.98 Outstanding, December 31, 2017 2,339,905 9.32 7.41 159 Granted 706,600 6.73 5.19 Exercised (1) (251,163 ) 4.57 3.53 1,028 Forfeited, cancelled or expired (123,436 ) 13.61 10.50 Outstanding, December 31, 2018 2,671,906 9.49 6.96 3,483 Exercisable, December 31, 2018 1,566,435 10.70 7.84 2,198 (1) During the year ended December 31, 2018, 49,502 (2017 – 63,425) stock options were exercised for the same number of common shares in exchange for cash. In the same period, the Company issued 106,474 (2017 – 4,405) common shares for the cashless exercise of 201,661 (2017 – 7,581) stock options.
Summary of Stock Option Outstanding and Exercisable	The following table summarizes the stock options outstanding and exercisable at December 31, 2018: Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Outstanding Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Options Exercisable Weighted Exercise Price U.S. $ (years) CAD $ U.S. $ CAD $ U.S. $ $1.96 - $2.74 529,675 2.34 3.42 2.51 529,675 3.42 2.51 $2.75 - $4.70 237,188 8.84 4.80 3.52 59,589 4.41 3.23 $4.71 - $5.35 508,050 9.19 6.48 4.75 — — — $5.36 - $7.59 391,469 7.61 9.49 6.96 209,664 9.95 7.30 $7.60 - $8.35 269,354 6.13 10.69 7.84 232,869 10.70 7.84 $8.36 - $8.98 365,052 8.17 11.47 8.41 184,322 11.48 8.42 $8.99 - $18.70 371,118 6.39 22.43 16.45 350,316 22.81 16.72 2,671,906 6.73 9.49 6.96 1,566,435 10.70 7.84
Schedule of Nonvested Stock Option Activity	A summary of the Company’s non-vested stock option activity and related information for the year ended December 31, 2018 is as follows: Number of Options Weighted Average Grant Date Fair CAD $ USD $ Non-vested, January 1, 2018 900,604 7.12 5.66 Granted 706,600 4.84 3.74 Vested (437,771 ) 8.47 6.54 Forfeited or cancelled (63,962 ) 6.70 5.17 Non-vested, December 31, 2018 1,105,471 5.61 4.11
Fair Value Assumptions for Stock Options	The weighted-average option pricing assumptions are as follows: Years ended December 31 2018 2017 Average risk-free interest rate 2.79 % 2.35 % Expected volatility 75 % 80 % Average expected term (in years) 7.38 7.37 Expected dividend yield 0.00 % 0.00 % Weighted average fair value of options granted $ 3.74 $ 5.02
Stock Based Compensation Expenses	Stock-based compensation expense is classified in the consolidated statements of operations and comprehensive income (loss) as follows: Years ended December 31, 2018 2017 Research and development $ 988 $ 985 General and administrative 1,772 1,251 $ 2,760 $ 2,236

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Future Minimum Annual Lease Payments for Operating Leases	Future minimum annual lease payments under existing operating lease commitments are as follows: Year ending December 31: 2019 1,128 2020 1,130 2021 1,069 2022 256 Total $ 3,583

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Income Tax (Recovery) Expense	Income tax (recovery) expense varies from the amounts that would be computed by applying the expected Canadian and provincial statutory income tax rate of 27% (2017 – 27% ) to loss before income taxes as shown in the following table: 2018 2017 Computed recoveries at Canadian federal and provincial tax rates $ (9,273 ) $ (8,000 ) Change in valuation allowance 10,472 9,210 Investment tax credits earned (1,567 ) (1,393 ) Tax attributes expired/utilized 911 683 Non-deductible expenditures (473 ) 594 Effect of tax rate increases — (1,444 ) Other (70 ) 350 Income tax (recovery) expense $ — $ —
Schedule of Net Deferred Income Tax Assets	The significant components of the Company’s net deferred income tax assets are as follows: 2018 2017 Deferred income tax assets Scientific research and experimental development pool $ 26,572 $ 25,056 Investment tax credits 23,808 22,872 Non-capital losses 22,035 13,645 Depreciable assets 5,710 5,360 Deferred financing fees 1,303 578 Other 98 114 Less - valuation allowance (79,526 ) (67,625 ) Net deferred income tax assets $ — $ —

Nature of the business (Details

Nature of the business (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accumulated deficit	$ 207,885	$ 173,388
Net loss	$ 34,497	$ 30,704

Basis of presentation (Details)

Basis of presentation (Details)	12 Months Ended
	Dec. 31, 2018
Xenon Pharmaceuticals USA Inc. [Member]
Basis of Presentation [Line Items]
Date of incorporation	Dec. 2, 2016

Significant Accounting Polici_4

Significant Accounting Policies - Property Plant and Equipment Estimated Useful Lives (Details)	12 Months Ended
	Dec. 31, 2018
Research Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Office Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, Plant and Equipment, Estimated Useful Lives	Over the lesser of lease term or estimated useful life

Significant Accounting Polici_5

Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2018USD ($)Segment	Dec. 31, 2017USD ($)
Accounting Policies [Abstract]
Impairment of Long-Lived Assets | $	$ 0	$ 0
Number of operating segment | Segment	1

Net Income (Loss) Per Common _3

Net Income (Loss) Per Common Share and Preferred Share (Details)	12 Months Ended
	Dec. 31, 2017shares
Stock Options and Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from the calculation of loss per common share	2,172,034
Convertible Preferred Shares [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares outstanding	0

Net Income (Loss) Per Common _4

Net Income (Loss) Per Common Share and Preferred Share - Reconciliation of Numerators and Denominators of Basic and Diluted Net Loss Per Common Share and Preferred Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Allocation of loss used attributed to shareholders:
Basic	$ (31,616)	$ (30,704)
Basic	$ 2,881
Weighted average number of shares:
Basic	19,425,711	17,985,061
Diluted	19,425,711	18,001,759
Basic	$ (1.63)	$ (1.71)
Diluted	$ (1.63)	$ (1.72)
Common Shares [Member]
Allocation of loss used attributed to shareholders:
Basic	$ (31,616)	$ (30,704)
Adjustment for change in fair value of liability classified stock options		(187)
Diluted	$ (31,616)	$ (30,891)
Weighted average number of shares:
Basic	19,425,711	17,985,061
Adjustment for dilutive effect of stock options		16,698
Diluted	19,425,711	18,001,759
Basic	$ (1.63)	$ (1.71)
Diluted	$ (1.63)	$ (1.72)
Preferred Shares [Member]
Allocation of loss used attributed to shareholders:
Basic	$ (2,881)
Diluted	$ (2,881)
Weighted average number of shares:
Basic	1,769,900
Diluted	1,769,900
Basic	$ (1.63)
Diluted	$ (1.63)

Property, Plant and Equipment -

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Less: accumulated depreciation and amortization	$ (16,199)	$ (15,638)
Net book value	991	1,070
Research Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	7,313	6,984
Office Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	1,046	1,043
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	2,461	2,311
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment	$ 6,370	$ 6,370

Accounts Payable and Accrued _3

Accounts Payable and Accrued Expenses - Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Trade payables	$ 665	$ 1,253
Employee compensation, benefits, and related accruals	1,728	1,017
Consulting and contracted research	1,404	817
Professional fees	237	252
Other	85	44
Total	$ 4,119	$ 3,383

Term Loan (Details)

Term Loan (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended				12 Months Ended
	Sep. 30, 2018	Aug. 31, 2018	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt instrument tranche amount funded					$ 15,500
Increase in warrants issued				36,008
Interest expense					1,394
Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Fair value of warrant					$ 247
Warrants outstanding to purchase common stock					86,419
Warrants exercise price per common share					$ 2.43
Warrant exercisable term					10 years
Number of shares issued for cashless exercise	72,325
Loan Agreement [Member] | Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Debt instrument, agreement date				2017-12
Loan Agreement [Member] | Silicon Valley Bank [Member] | Modification [Member]
Debt Instrument [Line Items]
Debt instrument, agreement date			2018-06
Loan Agreement [Member] | Silicon Valley Bank [Member] | Initial Tranche [Member]
Debt Instrument [Line Items]
Debt instrument tranche amount funded				$ 7,000		$ 7,000
Loan Agreement [Member] | Silicon Valley Bank [Member] | Initial Tranche [Member] | Modification [Member]
Debt Instrument [Line Items]
Debt instrument principal repayment period				30 months
Debt instrument principal repayment period on achievement of certain clinical milestones				24 months
Debt instrument, maturity date				Mar. 31, 2021
Loan Agreement [Member] | Silicon Valley Bank [Member] | Second Tranche [Member] | Modification [Member]
Debt Instrument [Line Items]
Debt instrument tranche amount funded			$ 5,000
Debt instrument, interest only payment end date			Sep. 30, 2018
Debt instrument principal repayment period			24 months
Debt instrument principal repayment period on achievement of certain clinical milestones			18 months
Debt instrument, maturity date			Sep. 30, 2020
Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument tranche amount funded				$ 7,000	$ 15,500	7,000
Interest expense					1,394	24
Final payment fee						1,008
Term Loan [Member] | Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Amortization of debt discount and accretion of final payment fee					$ 284	$ 11
Debt instrument, frequency periodic payment, interest					monthly
Term Loan [Member] | Silicon Valley Bank [Member] | Loan Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, interest only payment end date		Mar. 31, 2020
Debt instrument principal repayment period		30 months
Debt instrument, maturity date		Sep. 1, 2022
Aggregate principal amount of debt instrument		$ 15,500
Repayment of outstanding borrowings of loan agreement		12,000
Repayment of final payment fee		$ 485
Debt instrument, payment commencing period		2018-09
Debt instrument, final payment fee percentage		6.50%
Debt instrument prepayment fee		$ 295
Fair value of warrant		$ 291
Warrants outstanding to purchase common stock		40,000
Warrants exercise price per common share		$ 9.79
Warrant exercisable term		10 years
Debt instrument default interest payment above normal interest rate		5.00%
Term Loan [Member] | Silicon Valley Bank [Member] | Loan Agreement [Member] | Prior to First Anniversary [Member]
Debt Instrument [Line Items]
Debt instrument, prepayment fee payable on outstanding principal, in percentage		3.00%
Term Loan [Member] | Silicon Valley Bank [Member] | Loan Agreement [Member] | After First Anniversary, but Prior to Second Anniversary [Member]
Debt Instrument [Line Items]
Debt instrument, prepayment fee payable on outstanding principal, in percentage		2.00%
Term Loan [Member] | Silicon Valley Bank [Member] | Loan Agreement [Member] | After Second Anniversary [Member]
Debt Instrument [Line Items]
Debt instrument, prepayment fee payable on outstanding principal, in percentage		1.00%
Term Loan [Member] | Silicon Valley Bank [Member] | Loan Agreement [Member] | Prime Rate [Member]
Debt Instrument [Line Items]
Debt instrument, floating interest rate		0.50%
Term Loan [Member] | Silicon Valley Bank [Member] | Initial Tranche [Member] | Loan Agreement [Member]
Debt Instrument [Line Items]
Effective interest rate on initial tranche of debt instrument				9.25%	9.53%	9.25%

Term Loan - Schedule of Outstan

Term Loan - Schedule of Outstanding Loan and Unamortized Debt Discount Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Term loan	$ 15,500
Less: current portion		$ (700)
Loan payable, long-term	15,014	6,104
Term Loans [Member]
Debt Instrument [Line Items]
Term loan	15,500	7,000
Less: unamortized discount on loan	(600)	(203)
Less: current portion		(700)
Accrued portion of final payment fee	114	7
Loan payable, long-term	$ 15,014	$ 6,104

Term Loan - Schedule of Princip

Term Loan - Schedule of Principal Payments on Outstanding Debt (Details) $ in Thousands	Dec. 31, 2018USD ($)
Debt Disclosure [Abstract]
2,020	$ 5,167
2,021	6,200
2,022	4,133
Term loan	$ 15,500

Share Capital (Details)

Share Capital (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 01, 2019	Jun. 25, 2014	Sep. 30, 2018	Jul. 31, 2018	May 31, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Share Capital [Line Items]
Sale proceeds of common shares							$ 102,850
Number of Options Exercisable							1,566,435
Options Exercisable Weighted Average Remaining Contractual Life in Years							5 years 3 months
Aggregate fair value of options vested							$ 2,861	$ 2,047
Unrecognized stock-based compensation cost							$ 3,919
Unrecognized stock-based compensation expected to be recognized over a period							2 years 4 months 28 days
Series1 Preferred Shares
Share Capital [Line Items]
Conversion of shares							1,852,000
Common Shares [Member]
Share Capital [Line Items]
Conversion of shares							1,852,000
BVF Partners L.P [Member] | Exchange Agreement [Member]
Share Capital [Line Items]
Estimated weighted average cancellation price per share of common stock						$ 7.61
BVF Partners L.P [Member] | Exchange Agreement [Member] | Series1 Preferred Shares
Share Capital [Line Items]
Shares issued						2,868,000
Preferred shares convertible into common shares						one-for-one
Common shares issued on conversion of preferred stock						1
Maximum beneficial ownership limitation percentage for conversion of common stock issued and outstanding						9.99%
Maximum beneficial ownership limitation upon notice, percentage for conversion of common stock issued and outstanding						19.99%
Maximum beneficial percentage hold for conversion of number Of common stock issued and outstanding						5.00%
Minimum beneficial percentage hold for conversion of number Of common stock issued and outstanding.						5.00%
BVF Partners L.P [Member] | Exchange Agreement [Member] | Common Shares [Member]
Share Capital [Line Items]
Shares issued						2,868,000
Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Number of Options, Granted							153,209
Two Thousand Fourteen Plan [Member] | Subsequent Event [Member]
Share Capital [Line Items]
Common stock reserved for issuance	900,000
Maximum [Member] | Amended And Restated Stock Option Plan [Member]
Share Capital [Line Items]
Options exercise term							10 years
Options vesting period							4 years
Maximum [Member] | Two Thousand Fourteen Plan [Member]
Share Capital [Line Items]
Options exercise term		10 years
Options vesting period		4 years
Common Shares [Member]
Share Capital [Line Items]
Shares issued							9,540,000
Conversion of shares							1,852,000
Stifel [Member] | At-The-Market Equity Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares							$ 29,200
Stifel [Member] | At-The-Market Equity Offering [Member] | Maximum [Member]
Share Capital [Line Items]
Sale proceeds of common shares					$ 30,000
Stifel [Member] | At-The-Market Equity Offering [Member] | Common Shares [Member]
Share Capital [Line Items]
Shares issued							3,440,000
Jefferies and Stifel [Member] | At-The-Market Equity Offering Sales Agreement [Member]
Share Capital [Line Items]
Sale proceeds of common shares							$ 14,820
Jefferies and Stifel [Member] | Maximum [Member] | At-The-Market Equity Offering Sales Agreement [Member]
Share Capital [Line Items]
Sale proceeds of common shares				$ 50,000
Jefferies and Stifel [Member] | Common Shares [Member] | At-The-Market Equity Offering Sales Agreement [Member]
Share Capital [Line Items]
Shares issued							1,600,000
Jefferies and Stifel [Member] | Underwritten Public Offering [Member]
Share Capital [Line Items]
Sale proceeds of common shares			$ 59,220
Jefferies and Stifel [Member] | Underwritten Public Offering [Member] | Common Shares [Member]
Share Capital [Line Items]
Shares issued			4,500,000
Shares price			$ 14

Share Capital - Stock Option Ac

Share Capital - Stock Option Activity (Details) $ / shares in Units, $ in Thousands		12 Months Ended
		Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / shares$ / sharesshares	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2018$ / shares	Dec. 31, 2016USD ($)
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options Outstanding, Beginning balance		2,339,905		1,910,823
Number of Options, Granted		706,600		620,950
Number of Options, Exercised	[1]	(251,163)		(71,006)
Number of Options, Forfeited, cancelled or expired		(123,436)		(120,862)
Number of Options Outstanding, Ending balance		2,671,906		2,339,905
Number of Options Exercisable		1,566,435	1,566,435
Weighted Average Exercise Price Outstanding, Beginning balance | (per share)		$ 7.41	$ 9.32	$ 7.32	$ 9.84
Weighted Average Exercise Price, Granted | (per share)		5.19	6.73	6.69	8.69
Weighted Average Exercise Price, Exercised | (per share)	[1]	3.53	4.57	2.86	3.72
Weighted Average Exercise Price, Forfeited, cancelled and expired | (per share)		10.50	13.61	6.98	9.06
Weighted Average Exercise Price Outstanding, Ending balance | (per share)		6.96	$ 9.49	$ 7.41	$ 9.32
Weighted Average Exercise Price, Exercisable Ending balance | (per share)		$ 7.84	$ 7.84			$ 10.70
Aggregate Intrinsic Value, Outstanding | $		$ 3,483	$ 3,483	$ 159	$ 159		$ 4,464
Aggregate Intrinsic Value, Exercised | $	[1]	1,028		$ 108
Aggregate Intrinsic Value, Exercisable, Ending balance | $		$ 2,198	$ 2,198
[1]	During the year ended December 31, 2018, 49,502 (2017 – 63,425) stock options were exercised for the same number of common shares in exchange for cash. In the same period, the Company issued 106,474 (2017 – 4,405) common shares for the cashless exercise of 201,661 (2017 – 7,581) stock options.

Share Capital - Stock Option _2

Share Capital - Stock Option Activity (Parenthetical) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Options exercised for Number of Common Shares for cash	49,502	63,425
Common stock issued for cashless exercise	106,474	4,405
Cashless exercise of stock options	201,661	7,581

Share Capital - Summary of Stoc

Share Capital - Summary of Stock Option Outstanding and Exercisable (Details)	12 Months Ended
	Dec. 31, 2018$ / sharesshares	Dec. 31, 2018$ / sharesshares	Dec. 31, 2017$ / sharesshares	Dec. 31, 2017$ / sharesshares	Dec. 31, 2016$ / sharesshares	Dec. 31, 2016$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Options Outstanding	2,671,906	2,671,906	2,339,905	2,339,905	1,910,823	1,910,823
Options Outstanding Weighted Average Remaining Contractual Life in Years	6 years 8 months 23 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 6.96	$ 9.49	$ 7.41	$ 9.32	$ 7.32	$ 9.84
Number of Options Exercisable	1,566,435	1,566,435
Options exercisable, Weighted Average Exercise Price | (per share)	$ 7.84	$ 10.70
Range of Exercise Prices - $1.96 - $2.74 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	1.96
Exercise price range, upper range limit | $ / shares	$ 2.74
Number of Options Outstanding	529,675	529,675
Options Outstanding Weighted Average Remaining Contractual Life in Years	2 years 4 months 2 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 2.51	$ 3.42
Number of Options Exercisable	529,675	529,675
Options exercisable, Weighted Average Exercise Price | (per share)	$ 2.51	$ 3.42
Range of Exercise Prices - $2.75 - $4.70 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	2.75
Exercise price range, upper range limit | $ / shares	$ 4.70
Number of Options Outstanding	237,188	237,188
Options Outstanding Weighted Average Remaining Contractual Life in Years	8 years 10 months 2 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 3.52	$ 4.80
Number of Options Exercisable	59,589	59,589
Options exercisable, Weighted Average Exercise Price | (per share)	$ 3.23	$ 4.41
Range of Exercise Prices - $4.71 - $5.35 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	4.71
Exercise price range, upper range limit | $ / shares	$ 5.35
Number of Options Outstanding	508,050	508,050
Options Outstanding Weighted Average Remaining Contractual Life in Years	9 years 2 months 8 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 4.75	$ 6.48
Range of Exercise Prices - $5.36 - $7.59 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	5.36
Exercise price range, upper range limit | $ / shares	$ 7.59
Number of Options Outstanding	391,469	391,469
Options Outstanding Weighted Average Remaining Contractual Life in Years	7 years 7 months 9 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 6.96	$ 9.49
Number of Options Exercisable	209,664	209,664
Options exercisable, Weighted Average Exercise Price | (per share)	$ 7.30	$ 9.95
Range of Exercise Prices - $7.60 - $8.35 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	7.60
Exercise price range, upper range limit | $ / shares	$ 8.35
Number of Options Outstanding	269,354	269,354
Options Outstanding Weighted Average Remaining Contractual Life in Years	6 years 1 month 17 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 7.84	$ 10.69
Number of Options Exercisable	232,869	232,869
Options exercisable, Weighted Average Exercise Price | (per share)	$ 7.84	$ 10.70
Range of Exercise Prices - $8.36 - $8.98 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	8.36
Exercise price range, upper range limit | $ / shares	$ 8.98
Number of Options Outstanding	365,052	365,052
Options Outstanding Weighted Average Remaining Contractual Life in Years	8 years 2 months 1 day
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 8.41	$ 11.47
Number of Options Exercisable	184,322	184,322
Options exercisable, Weighted Average Exercise Price | (per share)	$ 8.42	$ 11.48
Range of Exercise Prices - $8.99 - $18.70 [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price range, lower range limit | $ / shares	8.99
Exercise price range, upper range limit | $ / shares	$ 18.70
Number of Options Outstanding	371,118	371,118
Options Outstanding Weighted Average Remaining Contractual Life in Years	6 years 4 months 20 days
Options Outstanding, Weighted Average Exercise Price | (per share)	$ 16.45	$ 22.43
Number of Options Exercisable	350,316	350,316
Options exercisable, Weighted Average Exercise Price | (per share)	$ 16.72	$ 22.81

Share Capital - Summary of Non-

Share Capital - Summary of Non-Vested Stock Option Activity (Details)	12 Months Ended
	Dec. 31, 2018$ / sharesshares	Dec. 31, 2018$ / sharesshares	Dec. 31, 2017$ / sharesshares	Dec. 31, 2017$ / sharesshares
Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares Roll Forward
Number of Options, Non-vested, Beginning balance	900,604	900,604
Number of Options, Granted	706,600	706,600	620,950	620,950
Number of Options, Vested	(437,771)	(437,771)
Number of Options, Forfeited or cancelled	(63,962)	(63,962)
Number of Options, Non-vested, Ending balance	1,105,471	1,105,471	900,604	900,604
Weighted Average Grant Date Fair Value, Non-vested, Beginning balance | (per share)	$ 5.66	$ 7.12
Weighted Average Grant Date Fair Value, Granted | (per share)	3.74	4.84	$ 5.02
Weighted Average Grant Date Fair Value, Vested | (per share)	6.54	8.47
Weighted Average Grant Date Fair Value, Forfeited or cancelled | (per share)	5.17	6.70
Weighted Average Grant Date Fair Value, Non-vested, Ending balance | (per share)	$ 4.11	$ 5.61	$ 5.66	$ 7.12

Share Capital - Fair Value Assu

Share Capital - Fair Value Assumptions for Stock Options (Details)	12 Months Ended
	Dec. 31, 2018$ / shares	Dec. 31, 2018$ / shares	Dec. 31, 2017$ / shares
Fair Value Assumptions For Stock Options [Abstract]
Average risk-free interest rate	2.79%	2.79%	2.35%
Expected volatility	75.00%	75.00%	80.00%
Average expected term (in years)	7 years 4 months 17 days	7 years 4 months 17 days	7 years 4 months 13 days
Expected dividend yield	0.00%	0.00%	0.00%
Weighted average fair value of options granted | (per share)	$ 3.74	$ 4.84	$ 5.02

Share Capital - Stock Based Com

Share Capital - Stock Based Compensation Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 2,760	$ 2,236
Research and development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	988	985
General and administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 1,772	$ 1,251

Concentrations of Market Risk (

Concentrations of Market Risk (Details) $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2018CAD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2017CAD ($)
Concentration Risk [Line Items]
Total outstanding loan balance, due within 12 months			$ 700
Interest Rate Risk [Member]
Concentration Risk [Line Items]
Cash and cash equivalents and marketable securities	$ 119,306
Interest rate risk, description	The Company does not enter into investments for trading or speculative purposes and has not used any derivative financial instruments to manage interest rate exposure. A 10% change in interest rates during any of the periods presented would not have had a material impact on the Company?s consolidated financial statements.
Total outstanding loan balance	$ 15,500
Total outstanding loan balance, due within 12 months
Interest Rate Risk [Member] | Prime Rate [Member] | Amended And Restated Loan And Security Agreement [Member] | Bank [Member]
Concentration Risk [Line Items]
Percentage of floating rate above prime rate	0.50%
Foreign Currency Exchange Risk [Member]
Concentration Risk [Line Items]
Cash and cash equivalents and marketable securities	$ 110,771	$ 11,644	$ 28,028	$ 19,619

Collaboration Agreements (Detai

Collaboration Agreements (Details) - USD ($)	1 Months Ended				12 Months Ended
	Mar. 31, 2018	Jul. 31, 2017	Sep. 30, 2015	Mar. 31, 2014	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2011
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Gain on termination of collaboration agreement	$ 4,398,000				$ 4,398,000
Additional milestone payments or royalties received					0
Development [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment received								$ 5,000,000
Health Canada [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment received							$ 8,000,000
Teva Pharmaceutical [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative development and license agreement revenue recognized					$ 0	$ 59,000
Teva Canada Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of common shares agreed to transfer and assign for cancellation	1,000,000
Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaborative development and license agreement termination date	Mar. 31, 2018
Genentech [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from upfront fee				$ 1,500,000
Milestone payment received		$ 250,000	$ 250,000
Potential Milestone Payments Receivable				$ 1,500,000					$ 613,000,000
Genentech [Member] | Pre-clinical And Clinical Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential Milestone Payments Receivable									45,500,000
Genentech [Member] | Regulatory Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential Milestone Payments Receivable									387,500,000
Genentech [Member] | Sales Based Milestone [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential Milestone Payments Receivable									180,000,000
Genentech [Member] | Licensing Agreements [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from upfront fee									10,000,000
Genentech [Member] | GDC-0276 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Proceeds from upfront fee									$ 10,000,000

Commitments and Contingencies_2

Commitments and Contingencies (Details)	1 Months Ended				12 Months Ended
	Sep. 30, 2018USD ($)	Jul. 31, 2017USD ($)	Apr. 30, 2017USD ($)	Mar. 31, 2017CAD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2015USD ($)	Aug. 31, 2015USD ($)
Commitments and Contingencies [Line Items]
Lease Agreement Description					for a 120-month term from April 1, 2012 to March 31, 2022,
Lease Expiration Date					Mar. 31, 2022
Amended Operating Leases Term					120 months
Operating Leases, Rent Expense					$ 1,194,000	$ 1,079,000
Asset Purchase Agreement [Member] | 1st Order Pharmaceuticals, Inc. [Member]
Commitments and Contingencies [Line Items]
Upfront fee paid			$ 350,000
Milestone payments paid						$ 700,000
Royalty obligations					0
Asset Purchase Agreement [Member] | 1st Order Pharmaceuticals, Inc. [Member] | Clinical Development Milestones [Member]
Commitments and Contingencies [Line Items]
Future potential payments					500,000
Asset Purchase Agreement [Member] | 1st Order Pharmaceuticals, Inc. [Member] | Regulatory Milestone [Member] | Maximum [Member]
Commitments and Contingencies [Line Items]
Future potential payments					6,000,000
Asset Purchase Agreement [Member] | 1st Order Pharmaceuticals, Inc. [Member] | Other Milestones [Member]
Commitments and Contingencies [Line Items]
Future potential payments					$ 1,500,000
Asset Purchase Agreement [Member] | 1st Order Pharmaceuticals, Inc. and Bausch Health Companies Inc. [Member]
Commitments and Contingencies [Line Items]
Agreement terminated in exchange for a one-time payment	$ 6,000,000
License Agreement [Member]
Commitments and Contingencies [Line Items]
Upfront fee paid		$ 1,000,000
License Agreement [Member] | Clinical Development Milestones [Member]
Commitments and Contingencies [Line Items]
Future potential payments		2,000,000
License Agreement [Member] | Regulatory Milestone [Member] | Maximum [Member]
Commitments and Contingencies [Line Items]
Future potential payments		$ 7,000,000
Medpace Clinical Development Service Agreement [Member]
Commitments and Contingencies [Line Items]
Service agreement, term					5 years
Committed service obligation								$ 7,000,000
Contractual obligation paid							$ 3,000,000
License, Manufacture and Supply Agreement [Member]
Commitments and Contingencies [Line Items]
Upfront fee paid				$ 500

Commitments and Contingencies -

Commitments and Contingencies - Future Minimum Annual Lease Payments for Operating Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
Commitments And Contingencies Disclosure [Abstract]
2,019	$ 1,128
2,020	1,130
2,021	1,069
2,022	256
Total	$ 3,583

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Tax Credit Carryforward [Line Items]
Income tax (recovery) expense	27.00%	27.00%
Unclaimed Tax Deductions Related To Scientific Research And Experimental Development Expenditures	$ 98,412	$ 92,799
Non-capital losses carried forward for tax purposes	$ 81,611	50,536
Tax Credit Carry forward, Expiration Date	Dec. 31, 2038
Unrecognized tax benefits of uncertain tax positions	$ 6,350	6,350
Canada Revenue Agency [Member] | Latest Tax Year [Member]
Tax Credit Carryforward [Line Items]
Tax year open for income tax examination	2,002
Canada Revenue Agency [Member] | Earliest Tax Year [Member]
Tax Credit Carryforward [Line Items]
Tax year open for income tax examination	2,017
Investment Tax credit [Member]
Tax Credit Carryforward [Line Items]
Tax credit available to offset federal taxes payable	$ 22,253	21,066
Provincial Tax Credit [Member]
Tax Credit Carryforward [Line Items]
Tax credit available to offset federal taxes payable	$ 7,640	$ 7,560

Income Taxes - Income Tax (Reco

Income Taxes - Income Tax (Recovery) Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Computed recoveries at Canadian federal and provincial tax rates	$ (9,273)	$ (8,000)
Change in valuation allowance	10,472	9,210
Investment tax credits earned	(1,567)	(1,393)
Tax attributes expired/utilized	911	683
Non-deductible expenditures	(473)	594
Effect of tax rate increases		(1,444)
Other	$ (70)	$ 350

Income Taxes - Net Deferred Inc

Income Taxes - Net Deferred Income Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets
Scientific research and experimental development pool	$ 26,572	$ 25,056
Investment tax credits	23,808	22,872
Non-capital losses	22,035	13,645
Depreciable assets	5,710	5,360
Deferred financing fees	1,303	578
Other	98	114
Less - valuation allowance	$ (79,526)	$ (67,625)

Related Parties (Details)

Related Parties (Details)	1 Months Ended
	Mar. 31, 2018shares
Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member]
Related Party Transaction [Line Items]
Collaborative development and license agreement termination month and year	2018-03
Teva Canada Limited [Member]
Related Party Transaction [Line Items]
Number of common shares agreed to transfer and assign for cancellation	1,000,000
Xenon Pharmaceuticals Inc [Member] | Teva Pharmaceuticals International GmbH and Teva Canada Limited [Member] | Minimum [Member]
Related Party Transaction [Line Items]
Percentage of ownership	5.00%
BVF Partners L.P [Member] | Exchange Agreement [Member] | Xenon Pharmaceuticals Inc [Member]
Related Party Transaction [Line Items]
Percentage of ownership	19.90%
BVF Partners L.P [Member] | Exchange Agreement [Member] | Series1 Preferred Shares
Related Party Transaction [Line Items]
Stock Issued	2,868,000
Common stock received in exchange of preferred shares	2,868,000