Omeros (OMER) 10-Q 9 May 19 2019 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2019	May 07, 2019
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Trading Symbol	OMER
Entity Registrant Name	OMEROS CORP
Entity Central Index Key	0001285819
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		49,057,866

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 4,054,000	$ 5,861,000
Short-term investments	43,168,000	54,637,000
Receivables, net	24,718,000	22,818,000
Inventory	736,000	88,000
Prepaid expense and other assets	4,195,000	6,463,000
Total current assets	76,871,000	89,867,000
Property and equipment, net	4,479,000	3,845,000
Right of use assets	17,514,000	0
Restricted investments	1,154,000	1,154,000
Advanced payments, non-current	1,228,000	1,070,000
Total assets	101,246,000	95,936,000
Liabilities and shareholders’ deficit
Accounts payable	7,121,000	6,281,000
Accrued expenses	34,823,000	30,186,000
Current portion of lease liabilities	2,561,000	889,000
Total current liabilities	44,505,000	37,356,000
Lease liabilities, non-current	26,578,000	1,578,000
Unsecured convertible senior notes, net	151,182,000	148,981,000
Deferred rent	0	8,177,000
Commitments and contingencies (Note 8)
Deferred rent
Preferred stock, par value $0.01 per share, 20,000,000 shares authorized; none issued and outstanding at March 31, 2019 and December 31, 2018.	0	0
Common stock, par value $0.01 per share, 150,000,000 shares authorized at March 31, 2019 and December 31, 2018; 49,022,428 and 49,011,684 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively.	490,000	490,000
Additional paid-in capital	552,961,000	549,479,000
Accumulated deficit	(674,470,000)	(650,125,000)
Additional paid-in capital	(121,019,000)	(100,156,000)
Accumulated deficit	$ 101,246,000	$ 95,936,000

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Preferred stock, par value (USD per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares	20,000,000	20,000,000
Preferred stock, Issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value (USD per share)	$ 0.01	$ 0.01
Common stock, authorized shares	150,000,000	150,000,000
Common stock, Issued shares	49,022,428	49,011,684
Common stock, outstanding shares	49,022,428	49,011,684

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Product sales, net	$ 21,779	$ 1,588
Cost of product sales
Cost of product sales	131	203
Research and development	26,255	18,140
Selling, general and administrative	14,632	10,934
Total costs and expenses	41,018	29,277
Loss from operations	(19,239)	(27,689)
Interest expense	(5,600)	(2,825)
Other income	494	460
Net loss	(24,345)	(30,054)
Comprehensive loss	$ (24,345)	$ (30,054)
Basic and diluted net loss per share (USD per share)	$ (0.50)	$ (0.62)
Weighted-average shares used to compute basic and diluted net loss per share (shares)	49,014,009	48,284,019

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net loss	$ (24,345)	$ (30,054)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	3,374	2,966
Non-cash interest expense	2,201	1,086
Depreciation and amortization	377	223
Changes in operating assets and liabilities:
Receivables	(1,900)	16,962
Inventory	(648)	196
Prepaid expenses and other assets	2,110	(840)
Accounts payable and accrued expenses	5,883	(1,835)
Net cash used in operating activities	(12,948)	(11,296)
Investing activities:
Purchases of property and equipment	(182)	(183)
Purchases of investments	(281)	(270)
Proceeds from the sale and maturities of investments	11,750	9,000
Net cash provided by investing activities	11,287	8,547
Financing activities:
Proceeds upon exercise of stock options and warrants	108	687
Payments on finance lease liabilities	(254)	(143)
Net cash provided by (used in) financing activities	(146)	544
Net decrease in cash and cash equivalents	(1,807)	(2,205)
Cash and cash equivalents at beginning of period	5,861	3,394
Cash and cash equivalents at end of period	4,054	1,189
Cash paid for interest
Cash paid for interest	82	1,739
Conversion of accrued interest to notes payable	$ 0	$ 838

Organization and Significant Ac

Organization and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Organization and Significant Accounting Policies	Organization and Significant Accounting Policies Organization We are a commercial-stage biopharmaceutical company committed to discovering, developing and commercializing small-molecule and protein therapeutics for large-market as well as orphan indications targeting inflammation, complement-mediated diseases, disorders of the central nervous system, and immune-related diseases, including cancers. Our first drug product, OMIDRIA, is marketed in the United States (U.S.) for use during cataract surgery or intraocular lens replacement. Basis of Presentation Our condensed consolidated financial statements include the financial position and results of operations of Omeros Corporation (Omeros) and our wholly owned subsidiaries. All inter-company transactions have been eliminated and we have determined we operate in one segment. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The information as of March 31, 2019 and for the three months ended March 31, 2019 and 2018 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2018 has been derived from our audited financial statements but does not include all of the information and footnotes required by GAAP for audited annual financial information. The accompanying unaudited condensed consolidated financial statements and related notes thereto should be read in conjunction with the audited consolidated financial statements and related notes thereto that are included in our Annual Report on Form 10-K for the year ended December 31, 2018 , which was filed with the U.S. Securities and Exchange Commission (SEC) on March 1, 2019. We continue to advance a series of clinical and preclinical programs (including three programs currently in Phase 3). CMS granted transitional pass-through reimbursement status for OMIDRIA from January 1, 2015 through December 31, 2017 for patients covered by Medicare Part B. On October 1, 2018, OMIDRIA pass-through reimbursement was reinstated for a two-year period and quarterly OMIDRIA net sales returned to historical levels. We believe OMIDRIA sales will continue to grow in 2019; however, due to the recent re-introduction of OMIDRIA, we cannot predict with precision the extent of growth in OMIDRIA revenues in 2019. As a result, despite our significant historical growth in OMIDRIA sales, meaningful growth in OMIDRIA sales in 2019 and beyond are not included in the determination regarding our prospects as a going concern. Similarly, we are unable to include in the determination any proceeds from debt transactions or other financing instruments despite our successful track record in accessing capital through these avenues. We also have not included any potential partnerships related to our products or product candidates. The conditions described above, when evaluated within the constraints of the accounting literature, raise substantial doubt with respect to our ability to meet our obligations through May 9, 2020 and, therefore, to continue as a going concern. We plan to continue to fund our operations through proceeds from sales of OMIDRIA and, if necessary, through other revenue sources and financial instruments as noted above. If these capital sources, for any reason, are needed but inaccessible, it would have a significantly negative effect our financial condition. Should it be necessary to manage our operating expenses, we would reduce our projected cash requirements through reduction of our expenses by delaying clinical trials, reducing selected research and development efforts, and/or implementing other restructuring activities. The accompanying consolidated financial statements have been prepared on a going-concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The accompanying consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from uncertainty related to our ability to continue as a going concern. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Significant items subject to such estimates include revenue recognition, stock-based compensation expense and accruals for clinical trials, manufacturing of drug product and clinical drug supply and contingencies. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances; however, actual results could differ from these estimates. Revenue Recognition When we enter into a customer contract, we perform the following five steps: (i) identify the contract 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) we satisfy a performance obligation. Product Sales, Net We generally record revenue from product sales when the product is delivered to our wholesalers. Product sales are recorded net of wholesaler distribution fees and estimated chargebacks, rebates, returns and purchase-volume discounts. Accruals or allowances are established for these deductions in the same period when revenue is recognized, and actual amounts incurred are offset against the applicable accruals or allowances. We reflect each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability depending on how the amount is expected to be settled. Right-of-Use Assets and Related Lease Liabilities On January 1, 2019, we adopted Accounting Standards Update (ASU) 2016-02, Leases , (Topic 842) using a modified retrospective approach. We elected the package of practical expedients permitted under the transition guidance, which allowed us to carryforward our historical assessment of whether 1) contracts contain leases, 2) lease classifications and 3) initial direct costs. Upon adoption we recognized right-of-use assets and lease liabilities of $17.7 million and $26.4 million , respectively, in our Consolidated Balance Sheet. The balance of the net right-of-use asset resulted from the reversal of the outstanding balance of deferred rent of $8.7 million . We record operating leases on our Consolidated Balance Sheet as right-of-use assets and recognize the related lease liabilities equal to the fair value of the lease payments using our incremental borrowing rate when the implicit rate in the lease agreement is not readily available. We recognize variable lease payments, when incurred. Costs associated with operating lease assets are recognized on a straight-line basis within operating expenses over the term of the lease. We record finance leases on our Consolidated Balance Sheet as a component of property and equipment and amortize these assets within operating expenses on a straight-line basis to their residual values over the shorter of the term of the underlying lease or the estimated useful life of the equipment. The interest component of a finance lease is included in interest expense and recognized using the effective interest method over the lease term. We account for leases with initial terms of 12 months or less as operating expenses on a straight-line basis over the lease term. Advance Payments Advance payments for goods or services that will be used or rendered for future research and development activities are deferred and then recognized as an expense as the related goods are delivered or the services are performed, or when the goods or services are no longer expected to be provided. Stock-Based Compensation On January 1, 2019, we adopted ASU 2018-07, Compensation — Stock Compensation, (Topic 958) which simplifies the accounting for share-based payments granted to non-employees for services by aligning it with the accounting for share-based payments to employees, with certain exceptions. The adoption was immaterial to our consolidated financial statements. Stock-based compensation expense is recognized for all share-based payments made to employees, directors and non-employees based on estimated fair values as of the date of grant. The fair value of our stock options is calculated using the Black-Scholes option-pricing model which requires judgmental assumptions including volatility, forfeiture rates and expected option life. We use the straight-line method to allocate stock-based compensation cost to reporting periods over each optionee’s requisite service period, which is generally the vesting period. Recent Accounting Pronouncement Not Yet Adopted In June 2016, the Financial Accounting Standards Board (FASB) issued ASU 2016-13, Financial Instruments — Credit Losses, (Topic 326) which changes how entities account for credit losses on most financial assets and certain other instruments, and expands disclosures. The standard is effective for annual and interim periods beginning after December 15, 2019 with early adoption permitted. We expect to adopt the standard on January 1, 2020 and are still in the process of evaluating the effect of adoption on our consolidated financial statements and disclosures.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common shares and dilutive common share equivalents outstanding for the period, determined using the treasury-stock method. Common share equivalents are excluded from the diluted net loss per share computation if their effect is anti-dilutive. The basic and diluted net loss per share amounts for the three months ended March 31, 2019 and 2018 were computed based on the shares of common stock outstanding during the respective periods. Potentially dilutive securities excluded from the diluted loss per share calculation are as follows: March 31, 2019 2018 Outstanding options to purchase common stock 11,840,521 9,640,452 Outstanding warrants to purchase common stock 243,115 100,602 Total potentially dilutive shares excluded from loss per share 12,083,636 9,741,054

Fair-Value Measurements

Fair-Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Fair-Value Measurements	Fair-Value Measurements As of March 31, 2019 , and December 31, 2018 , all investments were classified as short-term and available-for-sale on the accompanying Condensed Consolidated Balance Sheets. Investment income, which was included as a component of other income, consists of interest earned. On a recurring basis, we measure certain financial assets at fair value. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability, an exit price, in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The accounting standard establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs, where available. The following summarizes the three levels of inputs required: Level 1—Observable inputs for identical assets or liabilities, such as quoted prices in active markets; Level 2—Inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3—Unobservable inputs in which little or no market data exists, therefore they are developed using estimates and assumptions developed by us, which reflect those that a market participant would use. Our fair value hierarchy for our financial assets and liabilities measured at fair value on a recurring basis are as follows: March 31, 2019 Level 1 Level 2 Level 3 Total (In thousands) Assets: Money-market funds classified as non-current restricted cash and investments $ 1,154 $ — $ — $ 1,154 Money-market funds classified as short-term investments 43,168 — — 43,168 Total $ 44,322 $ — $ — $ 44,322 December 31, 2018 Level 1 Level 2 Level 3 Total (In thousands) Assets: Money-market funds classified as non-current restricted cash and investments $ 1,154 $ — $ — $ 1,154 Money-market funds classified as short-term investments 54,637 — — 54,637 Total $ 55,791 $ — $ — $ 55,791 Cash held in demand deposit accounts of $4.1 million and $5.9 million is excluded from our fair-value hierarchy disclosure as of March 31, 2019 and December 31, 2018 , respectively. There were no unrealized gains or losses associated with our short-term investments as of March 31, 2019 or December 31, 2018 . The carrying amounts reported in the accompanying Condensed Consolidated Balance Sheets for receivables, accounts payable, other current monetary assets and liabilities approximate fair value.

Certain Balance Sheet Accounts

Certain Balance Sheet Accounts	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
Certain Balance Sheet Accounts	Accounts Receivable, net Accounts receivable, net consist of the following: March 31, December 31, (In thousands) Trade receivables, net $ 24,580 $ 22,654 Sublease and other receivables 138 164 Total accounts receivables, net $ 24,718 $ 22,818 Trade receivables are shown net of $0.4 million and $0.4 million of chargeback and product return allowances as of March 31, 2019 and December 31, 2018 , respectively. Inventory Inventory consists of the following: March 31, December 31, (In thousands) Raw materials $ 43 $ 83 Work-in-progress 392 — Finished goods 301 5 Total inventory $ 736 $ 88 Property and Equipment, Net Property and equipment, net consists of the following: March 31, December 31, (In thousands) Finance leases $ 4,863 $ 4,034 Laboratory equipment 2,717 2,569 Computer equipment 896 862 Office equipment and furniture 625 625 Total cost 9,101 8,090 Less accumulated depreciation and amortization (4,622 ) (4,245 ) Total property and equipment, net $ 4,479 $ 3,845 For the three months ended March 31, 2019 and 2018 , depreciation and amortization expenses were $0.4 million and $0.2 million , respectively. Accrued Expenses Accrued expenses consist of the following: March 31, December 31, (In thousands) Contract research and development $ 14,460 $ 12,012 Sales rebates, fees and discounts 8,161 8,075 Employee compensation 2,233 2,714 Consulting and professional fees 3,344 3,669 Interest payable 4,995 1,677 Clinical trials 913 820 Other accrued expenses 717 1,219 Total accrued expenses $ 34,823 $ 30,186

Notes Payable

Notes Payable	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Notes Payable	Notes Payable In October 2016, we entered into a term loan agreement with CRG Servicing LLC (the CRG Loan) and, in November 2016, borrowed $80.0 million . In May 2018, we borrowed the remaining $45.0 million available under the CRG Loan and issued warrants to purchase up to 200,000 shares of our common stock with an exercise price of $23.00 per share. The warrants have a five-year term and remained outstanding as of March 31, 2019 . In November 2018, we issued unsecured convertible senior notes (see Note 6 - “Convertible Senior Notes”) and repaid the CRG Loan. Upon repayment, we incurred a loss on early extinguishment of debt of $13.0 million . As of March 31, 2019 and December 31, 2018 we did not have any notes payable outstanding. Convertible Senior Notes On November 15, 2018, we issued at face value $210.0 million aggregate principal amount of our 6.25% Convertible Senior Notes due 2023 (the Convertible Notes). The Convertible Notes are unsecured and accrue interest at an annual rate of 6.25% per annum, payable semi-annually in arrears on May 15 and November 15 of each year, beginning on May 15, 2019. The Convertible Notes will be convertible into cash, shares of our common stock or a combination thereof, as we elect at our sole discretion. The initial conversion rate is 52.0183 shares of our common stock per $1,000 of note principal (equivalent to an initial conversion price of approximately $19.22 per share of common stock), subject to adjustment in certain circumstances. As of March 31, 2019, all Convertible Notes remain outstanding. The balance of our Convertible Notes at March 31, 2019 and December 31, 2018, is as follows: March 31, December 31, (In thousands) Principal amount $ 210,000 $ 210,000 Unamortized discount (54,130 ) (56,156 ) Unamortized issuance costs attributable to principal amount (4,688 ) (4,863 ) Total Convertible Notes, net $ 151,182 $ 148,981 For more details on our Convertible Notes see Part II, Item 8, Note 8 - “Convertible Senior Notes” in our Annual Report on Form 10-K for the year ended December 31, 2018.

Convertible Senior Notes

Convertible Senior Notes	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Convertible Senior Notes	Notes Payable In October 2016, we entered into a term loan agreement with CRG Servicing LLC (the CRG Loan) and, in November 2016, borrowed $80.0 million . In May 2018, we borrowed the remaining $45.0 million available under the CRG Loan and issued warrants to purchase up to 200,000 shares of our common stock with an exercise price of $23.00 per share. The warrants have a five-year term and remained outstanding as of March 31, 2019 . In November 2018, we issued unsecured convertible senior notes (see Note 6 - “Convertible Senior Notes”) and repaid the CRG Loan. Upon repayment, we incurred a loss on early extinguishment of debt of $13.0 million . As of March 31, 2019 and December 31, 2018 we did not have any notes payable outstanding. Convertible Senior Notes On November 15, 2018, we issued at face value $210.0 million aggregate principal amount of our 6.25% Convertible Senior Notes due 2023 (the Convertible Notes). The Convertible Notes are unsecured and accrue interest at an annual rate of 6.25% per annum, payable semi-annually in arrears on May 15 and November 15 of each year, beginning on May 15, 2019. The Convertible Notes will be convertible into cash, shares of our common stock or a combination thereof, as we elect at our sole discretion. The initial conversion rate is 52.0183 shares of our common stock per $1,000 of note principal (equivalent to an initial conversion price of approximately $19.22 per share of common stock), subject to adjustment in certain circumstances. As of March 31, 2019, all Convertible Notes remain outstanding. The balance of our Convertible Notes at March 31, 2019 and December 31, 2018, is as follows: March 31, December 31, (In thousands) Principal amount $ 210,000 $ 210,000 Unamortized discount (54,130 ) (56,156 ) Unamortized issuance costs attributable to principal amount (4,688 ) (4,863 ) Total Convertible Notes, net $ 151,182 $ 148,981 For more details on our Convertible Notes see Part II, Item 8, Note 8 - “Convertible Senior Notes” in our Annual Report on Form 10-K for the year ended December 31, 2018.

Lease Liabilities

Lease Liabilities	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Lease Liabilities	Lease Liabilities We have operating leases related to our office and laboratory space in The Omeros Building. The initial term of the leases is through November 2027 and we have two options to extend the lease term, each by five years. We have finance leases for certain laboratory and office equipment that have lease terms expiring through December 2021. The lease-related assets and liabilities recorded on the balance sheet are as follows. Prior year interim financial statements were not recast under the new standard and, therefore, those amounts are not presented below. Classification on the Balance Sheet March 31, 2019 Assets (In thousands) Operating lease assets Right of use assets $ 17,514 Finance lease assets Property and equipment, net 3,413 Total lease assets $ 20,927 Liabilities Current: Operating Leases Current portion of lease liabilities $ 1,415 Finance Lease Current portion of lease liabilities 1,146 Non-current: Operating Lease liability, non-current 24,683 Finance Lease liability, non-current 1,895 Total lease liabilities $ 29,139 Weighted-average remaining lease term Operating leases 8.6 years Finance leases 2.9 years Weighted-average discount rate Operating leases (1) 12.85 % Finance leases 12.31 % (1) Upon adoption of the new lease standard, Topic 842, the discount rate used for existing operating leases was established at January 1, 2019 and represents our incremental borrowing rate. The components of total lease costs are as follows: Three Months Ended (In thousands) Lease cost Operating lease cost $ 1,031 Finance lease cost: Amortization 290 Interest 82 Short-term lease cost 138 Variable lease costs 486 Sublease income (224 ) Total lease cost $ 1,803 The supplemental cash flow information related to leases during 2019 is as follows: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 1,647 Operating cash flows from finance leases $ 82 Financing cash flows from finance leases $ 254 The future maturities of our lease liabilities as of March 31, 2019 are as follows: Operating Leases Finance Leases (In thousands) 2019 $ 3,499 $ 1,060 2020 4,770 1,224 2021 4,880 866 2022 4,995 290 2023 5,112 95 Thereafter 20,728 — Total undiscounted lease payments $ 43,984 $ 3,535 Less interest (17,886 ) (494 ) Lease liabilities $ 26,098 $ 3,041 As of March 31, 2019, we have a lease for additional space in The Omeros Building that will commence in late 2019. The expected lease term is seven years and the monthly lease payments are approximately $0.1 million over the expected term lease.
Lease Liabilities	Lease Liabilities We have operating leases related to our office and laboratory space in The Omeros Building. The initial term of the leases is through November 2027 and we have two options to extend the lease term, each by five years. We have finance leases for certain laboratory and office equipment that have lease terms expiring through December 2021. The lease-related assets and liabilities recorded on the balance sheet are as follows. Prior year interim financial statements were not recast under the new standard and, therefore, those amounts are not presented below. Classification on the Balance Sheet March 31, 2019 Assets (In thousands) Operating lease assets Right of use assets $ 17,514 Finance lease assets Property and equipment, net 3,413 Total lease assets $ 20,927 Liabilities Current: Operating Leases Current portion of lease liabilities $ 1,415 Finance Lease Current portion of lease liabilities 1,146 Non-current: Operating Lease liability, non-current 24,683 Finance Lease liability, non-current 1,895 Total lease liabilities $ 29,139 Weighted-average remaining lease term Operating leases 8.6 years Finance leases 2.9 years Weighted-average discount rate Operating leases (1) 12.85 % Finance leases 12.31 % (1) Upon adoption of the new lease standard, Topic 842, the discount rate used for existing operating leases was established at January 1, 2019 and represents our incremental borrowing rate. The components of total lease costs are as follows: Three Months Ended (In thousands) Lease cost Operating lease cost $ 1,031 Finance lease cost: Amortization 290 Interest 82 Short-term lease cost 138 Variable lease costs 486 Sublease income (224 ) Total lease cost $ 1,803 The supplemental cash flow information related to leases during 2019 is as follows: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 1,647 Operating cash flows from finance leases $ 82 Financing cash flows from finance leases $ 254 The future maturities of our lease liabilities as of March 31, 2019 are as follows: Operating Leases Finance Leases (In thousands) 2019 $ 3,499 $ 1,060 2020 4,770 1,224 2021 4,880 866 2022 4,995 290 2023 5,112 95 Thereafter 20,728 — Total undiscounted lease payments $ 43,984 $ 3,535 Less interest (17,886 ) (494 ) Lease liabilities $ 26,098 $ 3,041 As of March 31, 2019, we have a lease for additional space in The Omeros Building that will commence in late 2019. The expected lease term is seven years and the monthly lease payments are approximately $0.1 million over the expected term lease.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Contracts We have various agreements with third parties that collectively require payment of termination fees totaling $13.7 million as of March 31, 2019 if we cancel the work within specific time frames, either prior to commencing or during performance of the contracted services. Development Milestones and Product Royalties We have licensed a variety of intellectual property from third parties that we are currently developing or may develop in the future. These licenses may require milestone payments during the clinical development processes as well as low single to low double-digit royalties on the net income or net sales of the product. For the three months ended March 31, 2019 and the year ended December 31, 2018, development milestones incurred were immaterial and we did not owe any royalties.

Shareholders' Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Shareholders' Equity	Shareholders’ Deficit Common Stock For the three months ended March 31, 2019 , we received proceeds of $0.1 million upon the exercise of stock options which resulted in the issuance of 10,744 shares of common stock. For the three months ended March 31, 2018 , we received proceeds of $0.7 million upon the exercise of stock options and warrants which resulted in the issuance of 75,616 shares of common stock. Warrants In connection with the April 2018 amendment to the CRG Loan and the May 2018 borrowing under the CRG Loan, we issued warrants to purchase up to 200,000 shares of our common stock with an exercise price of $23.00 per share and total fair value of $1.4 million . The warrants have a five -year term and remain outstanding as of March 31, 2019 . Interim Condensed Consolidated Statements of Shareholders’ Deficit The changes in interim balances of the components of our shareholders’ deficit are as follows: Three Months Ended 2019 2018 (In thousands) Beginning and ending common stock $ 490 $ 483 Beginning additional paid-in capital $ 549,479 $ 520,071 Exercise of stock options 108 687 Stock-based compensation expense 3,374 2,966 Ending additional paid-in capital $ 552,961 $ 523,724 Beginning accumulated deficit $ (650,125 ) $ (523,368 ) Net loss (24,345 ) (30,054 ) Ending accumulated deficit $ (674,470 ) $ (553,422 )

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense includes the amortization of stock options granted to employees and non-employees and has been reported in our Condensed Consolidated Statements of Operations and Comprehensive Loss as follows: Three Months Ended 2019 2018 (In thousands) Research and development $ 1,494 $ 1,200 Selling, general and administrative 1,880 1,766 Total $ 3,374 $ 2,966 The fair value of each option grant to employees, directors and non-employees is estimated on the date of grant using the Black-Scholes option-pricing model. The following assumptions were applied to all stock option grants: Three Months Ended 2019 2018 Estimated weighted-average fair value $ 9.47 $ 9.79 Weighted-average assumptions Expected volatility 81 % 76 % Expected term, in years 6.0 6.1 Risk-free interest rate 2.48 % 2.54 % Expected dividend yield — % — % Stock option activity for all stock plans and related information is as follows: Options Outstanding Weighted- Average Exercise Price per Share Remaining Contractual Life (In years) Aggregate Intrinsic Value (In thousands) Balance at December 31, 2018 10,313,138 $ 11.22 Granted 1,606,500 13.49 Exercised (10,744 ) 10.01 Forfeited (68,373 ) 14.67 Balance at March 31, 2019 11,840,521 $ 11.51 6.62 $ 71,857 Vested and expected to vest at March 31, 2019 11,402,367 $ 11.41 6.53 $ 70,182 Exercisable at March 31, 2019 7,815,290 $ 10.31 5.35 $ 56,232 At March 31, 2019 , there were 4,025,230 unvested options outstanding that will vest over a weighted-average period of 9.1 years and 554,083 shares were available to grant. The total estimated compensation expense to be recognized on our unvested options is $15.6 million .

Organization and Significant _2

Organization and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Our condensed consolidated financial statements include the financial position and results of operations of Omeros Corporation (Omeros) and our wholly owned subsidiaries. All inter-company transactions have been eliminated and we have determined we operate in one segment. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. The information as of March 31, 2019 and for the three months ended March 31, 2019 and 2018 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2018 has been derived from our audited financial statements but does not include all of the information and footnotes required by GAAP for audited annual financial information. The accompanying unaudited condensed consolidated financial statements and related notes thereto should be read in conjunction with the audited consolidated financial statements and related notes thereto that are included in our Annual Report on Form 10-K for the year ended December 31, 2018 , which was filed with the U.S. Securities and Exchange Commission (SEC) on March 1, 2019.
Product Sales, Net	Product Sales, Net We generally record revenue from product sales when the product is delivered to our wholesalers. Product sales are recorded net of wholesaler distribution fees and estimated chargebacks, rebates, returns and purchase-volume discounts. Accruals or allowances are established for these deductions in the same period when revenue is recognized, and actual amounts incurred are offset against the applicable accruals or allowances. We reflect each of these accruals or allowances as either a reduction in the related accounts receivable or as an accrued liability depending on how the amount is expected to be settled.
Recently Adopted Pronouncements and Recent Accounting Pronouncements	Stock-Based Compensation

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2019
Earnings Per Share [Abstract]
Calculation of Historical Outstanding Dilutive Securities Not Included in Diluted Loss per Share	Potentially dilutive securities excluded from the diluted loss per share calculation are as follows: March 31, 2019 2018 Outstanding options to purchase common stock 11,840,521 9,640,452 Outstanding warrants to purchase common stock 243,115 100,602 Total potentially dilutive shares excluded from loss per share 12,083,636 9,741,054

Fair-Value Measurements (Tables

Fair-Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	Our fair value hierarchy for our financial assets and liabilities measured at fair value on a recurring basis are as follows: March 31, 2019 Level 1 Level 2 Level 3 Total (In thousands) Assets: Money-market funds classified as non-current restricted cash and investments $ 1,154 $ — $ — $ 1,154 Money-market funds classified as short-term investments 43,168 — — 43,168 Total $ 44,322 $ — $ — $ 44,322 December 31, 2018 Level 1 Level 2 Level 3 Total (In thousands) Assets: Money-market funds classified as non-current restricted cash and investments $ 1,154 $ — $ — $ 1,154 Money-market funds classified as short-term investments 54,637 — — 54,637 Total $ 55,791 $ — $ — $ 55,791

Certain Balance Sheet Accounts

Certain Balance Sheet Accounts (Tables)	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
Receivables	Accounts receivable, net consist of the following: March 31, December 31, (In thousands) Trade receivables, net $ 24,580 $ 22,654 Sublease and other receivables 138 164 Total accounts receivables, net $ 24,718 $ 22,818 Trade receivables are shown net of $0.4 million and $0.4 million of chargeback and product return allowances as of March 31, 2019 and December 31, 2018 , respectively. Inventory Inventory consists of the following: March 31, December 31, (In thousands) Raw materials $ 43 $ 83 Work-in-progress 392 — Finished goods 301 5 Total inventory $ 736 $ 88 Property and Equipment, Net Property and equipment, net consists of the following: March 31, December 31, (In thousands) Finance leases $ 4,863 $ 4,034 Laboratory equipment 2,717 2,569 Computer equipment 896 862 Office equipment and furniture 625 625 Total cost 9,101 8,090 Less accumulated depreciation and amortization (4,622 ) (4,245 ) Total property and equipment, net $ 4,479 $ 3,845 For the three months ended March 31, 2019 and 2018 , depreciation and amortization expenses were $0.4 million and $0.2 million , respectively. Accrued Expenses Accrued expenses consist of the following: March 31, December 31, (In thousands) Contract research and development $ 14,460 $ 12,012 Sales rebates, fees and discounts 8,161 8,075 Employee compensation 2,233 2,714 Consulting and professional fees 3,344 3,669 Interest payable 4,995 1,677 Clinical trials 913 820 Other accrued expenses 717 1,219 Total accrued expenses $ 34,823 $ 30,186
Schedule of Inventory, Current	Inventory consists of the following: March 31, December 31, (In thousands) Raw materials $ 43 $ 83 Work-in-progress 392 — Finished goods 301 5 Total inventory $ 736 $ 88
Property, Plant and Equipment	Property and equipment, net consists of the following: March 31, December 31, (In thousands) Finance leases $ 4,863 $ 4,034 Laboratory equipment 2,717 2,569 Computer equipment 896 862 Office equipment and furniture 625 625 Total cost 9,101 8,090 Less accumulated depreciation and amortization (4,622 ) (4,245 ) Total property and equipment, net $ 4,479 $ 3,845
Accrued Expenses	Accrued expenses consist of the following: March 31, December 31, (In thousands) Contract research and development $ 14,460 $ 12,012 Sales rebates, fees and discounts 8,161 8,075 Employee compensation 2,233 2,714 Consulting and professional fees 3,344 3,669 Interest payable 4,995 1,677 Clinical trials 913 820 Other accrued expenses 717 1,219 Total accrued expenses $ 34,823 $ 30,186

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Convertible Debt	The balance of our Convertible Notes at March 31, 2019 and December 31, 2018, is as follows: March 31, December 31, (In thousands) Principal amount $ 210,000 $ 210,000 Unamortized discount (54,130 ) (56,156 ) Unamortized issuance costs attributable to principal amount (4,688 ) (4,863 ) Total Convertible Notes, net $ 151,182 $ 148,981

Lease Liabilities (Tables)

Lease Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Lease, Cost [Table Text Block]	The lease-related assets and liabilities recorded on the balance sheet are as follows. Prior year interim financial statements were not recast under the new standard and, therefore, those amounts are not presented below. Classification on the Balance Sheet March 31, 2019 Assets (In thousands) Operating lease assets Right of use assets $ 17,514 Finance lease assets Property and equipment, net 3,413 Total lease assets $ 20,927 Liabilities Current: Operating Leases Current portion of lease liabilities $ 1,415 Finance Lease Current portion of lease liabilities 1,146 Non-current: Operating Lease liability, non-current 24,683 Finance Lease liability, non-current 1,895 Total lease liabilities $ 29,139 Weighted-average remaining lease term Operating leases 8.6 years Finance leases 2.9 years Weighted-average discount rate Operating leases (1) 12.85 % Finance leases 12.31 % (1) Upon adoption of the new lease standard, Topic 842, the discount rate used for existing operating leases was established at January 1, 2019 and represents our incremental borrowing rate. The components of total lease costs are as follows: Three Months Ended (In thousands) Lease cost Operating lease cost $ 1,031 Finance lease cost: Amortization 290 Interest 82 Short-term lease cost 138 Variable lease costs 486 Sublease income (224 ) Total lease cost $ 1,803 The supplemental cash flow information related to leases during 2019 is as follows: Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 1,647 Operating cash flows from finance leases $ 82 Financing cash flows from finance leases $ 254
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The future maturities of our lease liabilities as of March 31, 2019 are as follows: Operating Leases Finance Leases (In thousands) 2019 $ 3,499 $ 1,060 2020 4,770 1,224 2021 4,880 866 2022 4,995 290 2023 5,112 95 Thereafter 20,728 — Total undiscounted lease payments $ 43,984 $ 3,535 Less interest (17,886 ) (494 ) Lease liabilities $ 26,098 $ 3,041
Finance Lease, Liability, Maturity [Table Text Block]	The future maturities of our lease liabilities as of March 31, 2019 are as follows: Operating Leases Finance Leases (In thousands) 2019 $ 3,499 $ 1,060 2020 4,770 1,224 2021 4,880 866 2022 4,995 290 2023 5,112 95 Thereafter 20,728 — Total undiscounted lease payments $ 43,984 $ 3,535 Less interest (17,886 ) (494 ) Lease liabilities $ 26,098 $ 3,041

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2019
Equity [Abstract]
Schedule of Stockholders Equity [Table Text Block]	The changes in interim balances of the components of our shareholders’ deficit are as follows: Three Months Ended 2019 2018 (In thousands) Beginning and ending common stock $ 490 $ 483 Beginning additional paid-in capital $ 549,479 $ 520,071 Exercise of stock options 108 687 Stock-based compensation expense 3,374 2,966 Ending additional paid-in capital $ 552,961 $ 523,724 Beginning accumulated deficit $ (650,125 ) $ (523,368 ) Net loss (24,345 ) (30,054 ) Ending accumulated deficit $ (674,470 ) $ (553,422 )

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Expense	Stock-based compensation expense includes the amortization of stock options granted to employees and non-employees and has been reported in our Condensed Consolidated Statements of Operations and Comprehensive Loss as follows: Three Months Ended 2019 2018 (In thousands) Research and development $ 1,494 $ 1,200 Selling, general and administrative 1,880 1,766 Total $ 3,374 $ 2,966
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following assumptions were applied to all stock option grants: Three Months Ended 2019 2018 Estimated weighted-average fair value $ 9.47 $ 9.79 Weighted-average assumptions Expected volatility 81 % 76 % Expected term, in years 6.0 6.1 Risk-free interest rate 2.48 % 2.54 % Expected dividend yield — % — %
Stock Option Activity and Related Information	Stock option activity for all stock plans and related information is as follows: Options Outstanding Weighted- Average Exercise Price per Share Remaining Contractual Life (In years) Aggregate Intrinsic Value (In thousands) Balance at December 31, 2018 10,313,138 $ 11.22 Granted 1,606,500 13.49 Exercised (10,744 ) 10.01 Forfeited (68,373 ) 14.67 Balance at March 31, 2019 11,840,521 $ 11.51 6.62 $ 71,857 Vested and expected to vest at March 31, 2019 11,402,367 $ 11.41 6.53 $ 70,182 Exercisable at March 31, 2019 7,815,290 $ 10.31 5.35 $ 56,232

Organization and Significant _3

Organization and Significant Accounting Policies (Detail)	3 Months Ended
	Mar. 31, 2019USD ($)segment	Jan. 01, 2019USD ($)	Dec. 31, 2018USD ($)
Accounting Policies [Abstract]
Number of operating segments | segment	1
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use assets	$ 17,514,000		$ 0
Lease liabilities	$ 26,098,000
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right of use assets		$ 17,700,000
Lease liabilities		26,400,000
Deferred Rent Credit		$ 8,700,000

Net Loss Per Share - Calculatio

Net Loss Per Share - Calculation of Historical Outstanding Dilutive Securities Not Included in Diluted Loss Per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding dilutive securities not included in diluted loss per share calculation	12,083,636	9,741,054
Outstanding options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding dilutive securities not included in diluted loss per share calculation		9,640,452
Outstanding warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding dilutive securities not included in diluted loss per share calculation	243,115	100,602

Fair-Value Measurements - Finan

Fair-Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Total	$ 44,322	$ 55,791
Restricted Cash, Noncurrent
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	1,154	1,154
Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	43,168	54,637
Level 1
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Total	44,322	55,791
Level 1 | Restricted Cash, Noncurrent
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	1,154	1,154
Level 1 | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	43,168	54,637
Level 2
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Total	0	0
Level 2 | Restricted Cash, Noncurrent
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	0	0
Level 2 | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Total	0	0
Level 3 | Restricted Cash, Noncurrent
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	0	0
Level 3 | Short-term Investments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds, fair value disclosure	$ 0	$ 0

Fair-Value Measurements - Narra

Fair-Value Measurements - Narrative (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Cash and cash equivalents	$ 4,054,000	$ 5,861,000	$ 1,189,000	$ 3,394,000
Unrealized gain (loss) on investments	$ 0	$ 0

Certain Balance Sheet Account_2

Certain Balance Sheet Accounts - Accounts Receivable, Net (Detail) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Trade receivables, net	$ 24,580,000	$ 22,654,000
Sublease and other receivables	138,000	164,000
Total accounts receivables, net	24,718,000	22,818,000
Charge back	$ 400,000	$ 439,000

Certain Balance Sheet Account_3

Certain Balance Sheet Accounts - Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 43	$ 83
Work-in-process	392	0
Finished goods	301	5
Inventory	$ 736	$ 88

Certain Balance Sheet Account_4

Certain Balance Sheet Accounts - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total cost	$ 9,101		$ 8,090
Less accumulated depreciation and amortization	(4,622)		(4,245)
Total property and equipment, net	4,479		3,845
Depreciation and amortization	377	$ 223
Finance leases
Property, Plant and Equipment [Line Items]
Total cost	4,863		4,034
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total cost	2,717		2,569
Computer equipment
Property, Plant and Equipment [Line Items]
Total cost	896		862
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Total cost	$ 625		$ 625

Certain Balance Sheet Account_5

Certain Balance Sheet Accounts - Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Contract research and development	$ 14,460	$ 12,012
Sales rebates, fees and discounts	8,161	8,075
Employee compensation	2,233	2,714
Consulting and professional fees	3,344	3,669
Interest payable	4,995	1,677
Clinical trials	913	820
Other accruals	717	1,219
Total accrued liabilities	$ 34,823	$ 30,186

Notes Payable (Detail)

Notes Payable (Detail) - USD ($)	1 Months Ended
	Nov. 30, 2018	May 31, 2018	Apr. 30, 2018	Oct. 26, 2016
Debt Instrument [Line Items]
Shares of common stock to purchase by warrant (in shares)			200,000
Warrant exercise price (in USD per share)			$ 23
CRG Loan
Debt Instrument [Line Items]
Debt issued				$ 80,000,000
Remaining borrowing capacity		$ 45,000,000
Gain (Loss) on Extinguishment of Debt	$ (13,000,000)

Convertible Senior Notes - Narr

Convertible Senior Notes - Narrative (Details) - Convertible Debt - Convertible Notes - USD ($)	Nov. 15, 2018	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Face Amount	$ 210,000,000	$ 210,000	$ 210,000
Interest Rate	6.25%
Conversion Price	$ 52.0183
If-converted Value in Excess of Principal	$ 1,000
Stock Price Trigger (USD per share)	$ 19.22

Convertible Senior Notes - Bala

Convertible Senior Notes - Balance of Convertible Note (Details) - Convertible Debt - Convertible Notes - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Nov. 15, 2018
Debt Instrument [Line Items]
Face Amount	$ 210,000	$ 210,000	$ 210,000,000
Unamortized debt discount	(54,130)	(56,156)
Unamortized debt issuance costs	(4,688)	(4,863)
Net carrying amount of Convertible Notes	$ 151,182	$ 148,981

Lease Liabilities (Details)

Lease Liabilities (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract	7 years
Lessee, Operating Lease, Term of Contract	5 years
Classification on the Balance Sheet
Operating lease assets	$ 17,514,000	$ 0
Finance lease assets	3,413,000
Total lease assets	20,927,000
Operating Leases	1,415,000
Finance Lease	1,146,000
Operating	24,683,000
Finance	1,895,000
Total lease liabilities	$ 29,139,000
Operating leases	8 years 7 months 6 days
Finance leases	2 years 10 months 24 days
Operating leases (1)	12.85%
Finance leases	12.31%
Operating cash flows from operating leases	$ 1,647,000
Operating cash flows from finance leases	82,000
Financing cash flows from finance leases	254,000
Lease cost
Operating lease cost	1,031,000
Amortization	290,000
Interest	82,000
Short-term lease cost	138,000
Variable lease costs	486,000
Sublease income	(224,000)
Total lease cost	1,803,000
Lessee, Operating Lease, Lease Not yet Commenced. Amount	$ 100,000

Lease Liabilities - Maturities

Lease Liabilities - Maturities (Details) $ in Thousands	Mar. 31, 2019USD ($)
Operating Leases
2019	$ 3,499
2020	4,770
2021	4,880
2022	4,995
2023	5,112
Thereafter	20,728
Total undiscounted lease payments	43,984
Less interest	(17,886)
Lease liabilities	26,098
Finance Leases
2019	1,060
2020	1,224
2021	866
2022	290
2023	95
Thereafter	0
Total undiscounted lease payments	3,535
Less interest	(494)
Lease liabilities	$ 3,041

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Mar. 31, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Contract termination fees	$ 13.7

Shareholders' Equity (Detail)

Shareholders' Equity (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Class of Warrant or Right [Line Items]
Proceeds upon exercise of stock options and warrants		$ 108	$ 687
Stock issued from exercise of stock options and warrants (in shares)		10,744
Shares of common stock to purchase by warrant (in shares)	200,000
Warrant exercise price (in USD per share)	$ 23
Fair value	$ 1,400
Warrant term	5 years
Common stock, Issued shares		49,022,428		49,011,684
Warrant
Class of Warrant or Right [Line Items]
Shares of common stock to purchase by warrant (in shares)	200,000

Shareholders' Equity - Equity (

Shareholders' Equity - Equity (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Class of Stock [Line Items]
Stockholders' Equity Attributable to Parent	$ (100,156,000)
Net loss	(24,345,000)	$ (30,054,000)
Stockholders' Equity Attributable to Parent	(121,019,000)
Common Stock [Member]
Class of Stock [Line Items]
Stockholders' Equity Attributable to Parent	490,000	483,000
Additional Paid-in Capital [Member]
Class of Stock [Line Items]
Stockholders' Equity Attributable to Parent	549,479,000	520,071
Stock Issued During Period, Value, Stock Options Exercised	108,000	687
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition	3,374,000	2,966
Stockholders' Equity Attributable to Parent	552,961,000	523,724
Retained Earnings [Member]
Class of Stock [Line Items]
Stockholders' Equity Attributable to Parent	(650,125,000)	(523,368,000)
Net loss	(24,345,000)	(30,054,000)
Stockholders' Equity Attributable to Parent	$ (674,470,000)	$ (553,422,000)

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total	$ 3,374	$ 2,966
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,494	1,200
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,880	$ 1,766

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Employee Option Grant Estimated on Date of Grant (Details) - Equity Option - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated weighted-average fair value (USD per share)	$ 9.47	$ 9.79
Weighted Average
Weighted-average assumptions
Expected volatility	81.00%	76.00%
Expected term, in years	6 years 1 month 6 days	6 years 1 month 6 days
Risk-free interest rate	2.48%	2.54%
Expected dividend yield	0.00%	0.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity and Related Information (Detail)	3 Months Ended
	Mar. 31, 2019USD ($)$ / sharesshares
Options Outstanding
Beginning balance (shares) | shares	10,313,138
Granted (shares) | shares	1,606,500
Exercised (shares) | shares	(10,744)
Forfeited (shares) | shares	(68,373)
Ending balance (shares) | shares	11,840,521
Vested and expected to vest (shares) | shares	11,402,367
Exercisable (shares) | shares	7,815,290
Weighted-Average Exercise Price per Share
Beginning balance (USD per share) | $ / shares	$ 11.22
Granted (USD per share) | $ / shares	13.49
Exercised (USD per share) | $ / shares	10.01
Forfeited (USD per share) | $ / shares	14.67
Ending balance (USD per share) | $ / shares	11.51
Vested and expected to vest (USD per share) | $ / shares	11.41
Exercisable (USD per share) | $ / shares	$ 10.31
Weighted- Average Remaining Contractual Life
Balance (in years)	6 years 7 months 13 days
Vested and expected to vest (in years)	6 years 6 months 12 days
Exercisable (in years)	5 years 4 months 6 days
Aggregate Intrinsic Value
Balance | $	$ 71,857
Vested and expected to vest | $	70,182
Exercisable | $	$ 56,232

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Unvested options outstanding (shares)	4,025,231
Period for recognition	9 years 1 month 6 days
Shares available for future grants (shares)	554,083
Unrecognized compensation expense | $	$ 15.6