Omeros (OMER) 10-Q 9 Nov 20 2020 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Nov. 05, 2020
Document Document and Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2020
Entity File Number	001-34475
Entity Registrant Name	OMEROS CORPORATION
Entity Incorporation, State or Country Code	WA
Entity Tax Identification Number	91-1663741
Entity Address, Address Line One	201 Elliott Avenue West
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98119
City Area Code	206
Local Phone Number	676-5000
Title of 12(b) Security	Common Stock
Trading Symbol	OMER
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		61,652,326
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Central Index Key	0001285819
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 21,075	$ 3,084
Short-term investments	132,448	57,704
Receivables, net	37,379	35,185
Inventory	1,542	1,147
Prepaid expense and other assets	3,541	6,625
Total current assets	195,985	103,745
Property and equipment, net	2,950	3,829
Right of use assets	26,116	27,082
Restricted investments	1,154	1,154
Advanced payments, non-current	870	1,159
Total assets	227,075	136,969
Current liabilities:
Accounts payable	7,017	5,328
Accrued expenses	36,948	46,627
Current portion of lease liabilities	3,754	3,504
Total current liabilities	47,719	55,459
Lease liabilities, non-current	29,717	32,318
Unsecured convertible senior notes, net	232,808	158,213
Deferred tax liability	4,157
Commitments and contingencies (Note 8)
Shareholders' deficit:
Preferred stock, par value $0.01 per share, 20,000,000 shares authorized; none issued and outstanding at September 30, 2020 and December 31, 2019.
Common stock, par value $0.01 per share, 150,000,000 shares authorized at September 30, 2020 and December 31, 2019; 61,651,152 and 54,200,810 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively.	616	542
Additional paid-in capital	747,457	625,048
Accumulated deficit	(835,399)	(734,611)
Total shareholders' deficit	(87,326)	(109,021)
Total liabilities and shareholders' deficit	$ 227,075	$ 136,969

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2020	Dec. 31, 2019
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	61,651,152	54,200,810
Common stock, outstanding shares	61,651,152	54,200,810

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Product sales, net	$ 26,114	$ 29,856	$ 63,181	$ 78,389
Costs and expenses:
Cost of product sales	401	278	815	464
Research and development	31,316	23,746	84,359	69,108
Selling, general and administrative	19,825	16,933	54,792	48,493
Total costs and expenses	51,542	40,957	139,966	118,065
Loss from operations	(25,428)	(11,101)	(76,785)	(39,676)
Loss on early extinguishment of debt	(13,374)		(13,374)
Interest expense	(6,882)	(5,715)	(18,763)	(16,846)
Other (expense) income	(633)	353	280	1,261
Loss before income taxes	(46,317)	(16,463)	(108,642)	(55,261)
Income tax benefit	7,854		7,854
Net loss	(38,463)	(16,463)	(100,788)	(55,261)
Comprehensive loss	$ (38,463)	$ (16,463)	$ (100,788)	$ (55,261)
Basic and diluted net loss per share (USD per share)	$ (0.66)	$ (0.33)	$ (1.81)	$ (1.12)
Weighted-average shares used to compute basic and diluted net loss per share ( in shares)	58,233,988	49,373,156	55,682,379	49,157,055
Revenue, Product and Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember
Cost, Product and Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember	us-gaap:ProductMember

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Operating activities:
Net loss	$ (100,788)	$ (55,261)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	11,122	10,468
Non-cash interest expense	8,169	6,790
Depreciation and amortization	1,218	1,262
Loss on early extinguishment of debt	13,374
Deferred income tax	(7,854)
Fair value settlement upon termination of cap call contract	838
Changes in operating assets and liabilities:
Receivables	(2,194)	(7,113)
Inventory	(395)	(1,085)
Prepaid expenses and other assets	3,533	959
Accounts payable and accrued expenses	(8,702)	6,921
Net cash used in operating activities	(81,679)	(37,059)
Investing activities:
Purchases of property and equipment	(283)	(318)
Purchases of investments	(133,190)	(594)
Proceeds from the sale and maturities of investments	58,446	36,750
Net cash (used in) provided by investing activities	(75,027)	35,838
Financing activities:
Proceeds from issuance of convertible senior notes, net of issuance costs	218,245
Purchases of capped calls related to convertible senior notes	(23,223)
Payments for repurchases of convertible senior notes	(125,638)
Proceeds from termination of capped call contracts	7,549
Proceeds from issuance of common stock, net	93,675
Proceeds upon exercise of stock options	4,978	5,034
Principal payments on finance lease liabilities	(889)	(813)
Net cash provided by financing activities	174,697	4,221
Net increase in cash and cash equivalents	17,991	3,000
Cash and cash equivalents at beginning of period	3,084	5,861
Cash and cash equivalents at end of period	21,075	8,861
Supplemental cash flow information
Cash paid for interest	8,564	6,811
Property acquired under finance lease	$ 216	$ 886

Organization and Significant Ac

Organization and Significant Accounting Policies	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Organization and Significant Accounting Policies	Note 1—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, addiction 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 intercompany 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 September 30, 2020 and December 31, 2019 and for the three and nine months ended September 30, 2020 and 2019 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2019 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, 2019, which was filed with the U.S. Securities and Exchange Commission (SEC) on March 2, 2020. Risks and Uncertainties In its 2021 outpatient prospective payment system (OPPS) proposed rule, the Centers for Medicare and Medicaid Services (CMS), a part of the Department of Health and Human Services (HHS), confirmed the October 1, 2020 expiration of pass-through reimbursement for OMIDRIA and indicated an intention to package payment for OMIDRIA with payment for the associated surgical procedure in both the hospital outpatient department (HOPD) and ambulatory surgery center (ASC) settings. We are continuing to pursue administrative and legislative avenues to secure separate payment for OMIDRIA; however, we cannot provide assurance that these efforts will be successful. The outbreak of the novel strain of coronavirus (SARS-CoV-2) that causes COVID-19 and the responses to the global pandemic by various governmental authorities, the medical community and others continue to have a significant impact on our business. In March 2020, ASCs and hospitals using OMIDRIA postponed nearly all cataract surgery in response to recommendations from government and medical organizations. As a result, we did not record any sales of OMIDRIA to our wholesalers from March 25 to May 19, 2020. However, by the end of June 2020, the run rate of weekly OMIDRIA sales had recovered to levels approximating those seen prior to the pandemic. Due to the unknown magnitude, duration and outcome of the COVID-19 pandemic, it is not possible to estimate precisely its impact on our business, operations or financial results; however, the impact has been and could continue to be material. As of September 30, 2020, we had cash, cash equivalents and short-term investments of $153.5 million and an accounts receivable-based line of credit that allows us to borrow up to the lesser of $50.0 million or 85% of our accounts receivable borrowing base, less certain reserves. We have incurred losses from operations of $76.8 million for the nine months ended September 30, 2020, and cash used in operating activities was $81.7 million for the nine months ended September 30, 2020. We will continue to incur losses from operating activities until our revenues exceed operating costs and debt service obligations. OMIDRIA pass-through reimbursement from CMS expired on October 1, 2020. If continued separate payment is determined not to be reasonably achievable in the near term, we have developed a commercial strategy that can be quickly implemented to lower the per-vial sales price of OMIDRIA to achieve substantially larger sales volumes. We believe that this approach would result in substantial revenues from OMIDRIA, in part because CMS Medicare Part B beneficiaries only represent approximately 45% of cataract surgery procedures annually. We anticipate narsoplimab for HSCT-TMA will receive FDA approval and will launch in early to mid-2021. Currently we cannot fully predict the timing or the magnitude of narsoplimab revenues, but we believe they will be significant. Execution of our sales and marketing strategies for the launch of narsoplimab for HSCT-TMA is underway. These plans include various milestones at which we commit to incremental activities, providing for flexibility in the timing of costs incurred should the approval of narsoplimab be accelerated or delayed. If warranted, we will adjust the timing and associated costs of our HSCT-TMA launch activities as we advance through the biologics license application (BLA) review and approval process. We plan to continue to fund our operations for at least the next twelve months with our cash and investments on hand, from sales of OMIDRIA and, if FDA approval is granted, from sales of narsoplimab for HSCT-TMA. There is also the possibility that we could generate revenue from sales of narsoplimab for the treatment of COVID-19. In addition, we may utilize funds available under our accounts receivable-based line of credit, which allows us to borrow up to 85% of our available accounts receivable borrowing base, less certain reserves, or $50.0 million, whichever is less. Should it be necessary or determined to be strategically advantageous, we also could pursue debt financings, public and private offerings of our equity securities similar to those we have completed previously, or other strategic transactions, which may include licensing a portion of our existing technology. 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, or implementing other restructuring activities. 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 other contingencies. We base our estimates on historical experience and on various other factors, including the impact of the COVID-19 pandemic, 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. 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 We record operating leases 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 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. Income Taxes Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their tax bases. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. We recognize the effect of income tax positions only if those positions are more likely than not of being sustained upon an examination. A valuation allowance is established when it is more likely than not that the deferred tax assets will not be realized. Stock-Based Compensation Stock-based compensation expense is recognized for all share-based payments 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. Recently Adopted Pronouncements In June 2016, the Financial Accounting Standards Board 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 adopted the standard on January 1, 2020 and the adoption did not have a material impact on our consolidated financial statements and disclosures. ​ Recent Accounting Pronouncements Not Yet Adopted In August 2020, the Financial Accounting Standards Board Debt—Debt with Conversion Options and Derivatives and Hedging—Contracts in Entity’s Own Equity Derivatives and Hedging convertible debt instrument was issued at a substantial premium. Among other potential impacts, this change is expected to reduce reported interest expense, increase reported net income, and result in a reclassification of certain conversion feature balance sheet amounts from stockholders’ equity to liabilities as it relates to the Company’s convertible senior notes. Additionally, ASU 2020-06 requires the application of the if-converted method to calculate the impact of convertible instruments on diluted earnings per share (EPS), which is consistent with the Company’s accounting treatment under the current standard. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021, with early adoption permitted for fiscal years beginning after December 15, 2020, and can be adopted on either a fully retrospective or modified retrospective basis. The Company is evaluating the impact of this pronouncement on its consolidated financial statements.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	Note 2—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 and nine months ended September 30, 2020 and 2019 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ September 30, ​ September 30, ​ 2020 2019 2020 2019 Outstanding options to purchase common stock 1,456,454 3,026,871 ​ 1,777,393 2,829,807 Outstanding warrants to purchase common stock 9,828 18,128 ​ 11,712 16,923 Total potentially dilutive shares excluded from loss per share 1,466,282 3,044,999 ​ 1,789,105 2,846,730 ​

Certain Balance Sheet Accounts

Certain Balance Sheet Accounts	9 Months Ended
	Sep. 30, 2020
Receivables [Abstract]
Certain Balance Sheet Accounts	Note 3—Certain Balance Sheet Accounts Accounts Receivable, net Accounts receivable, net consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ ​ (In thousands) Trade receivables, net ​ $ 37,218 ​ $ 35,074 Sublease and other receivables ​ 161 ​ 111 Total accounts receivables, net ​ $ 37,379 ​ $ 35,185 ​ Trade receivables as of September 30, 2020 are shown net of $8.7 million of product return and chargeback allowances. Trade receivables as of December 31, 2019 are shown net of $1.6 million of chargeback allowances. Inventory Inventory consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ ​ (In thousands) Raw materials $ 79 $ 91 Work-in-progress ​ 797 ​ 338 Finished goods ​ 666 ​ 718 Total inventory $ 1,542 $ 1,147 ​ Property and Equipment, Net Property and equipment, net consists of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Finance leases ​ $ 5,690 ​ $ 5,474 Laboratory equipment ​ 2,903 ​ 2,844 Computer equipment ​ 985 ​ 921 Office equipment and furniture ​ 625 ​ 625 Total cost ​ 10,203 ​ 9,864 Less accumulated depreciation and amortization ​ (7,253) ​ (6,035) Total property and equipment, net ​ $ 2,950 ​ $ 3,829 ​ Depreciation expense for the three months ended September 30, 2020 and 2019 was $0.4 million for both periods, respectively. Depreciation expense for the nine months ended September 30, 2020 and 2019 was $1.2 million and $1.3 million, respectively. Accrued Expenses Accrued expenses consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Sales rebates, fees and discounts ​ $ 10,201 ​ $ 10,870 Contract research and development ​ ​ 8,813 ​ ​ 24,107 Employee compensation ​ 6,415 ​ 3,546 Consulting and professional fees ​ 5,479 ​ 3,610 Interest payable ​ 3,736 ​ 1,640 Clinical trials ​ 1,482 ​ 1,982 Other accrued expenses ​ 822 ​ 872 Total accrued expenses ​ $ 36,948 ​ $ 46,627 ​ ​

Fair-Value Measurements

Fair-Value Measurements	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Fair-Value Measurements	Note 4—Fair-Value Measurements As of September 30, 2020, and December 31, 2019, 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: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ Level 1 Level 2 Level 3 Total ​ ​ (In thousands) Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money-market funds classified as non-current restricted investments ​ $ 1,154 ​ $ — ​ $ — ​ $ 1,154 Money-market funds classified as short-term investments ​ 132,448 ​ — ​ — ​ 132,448 Total ​ $ 133,602 ​ $ — ​ $ — ​ $ 133,602 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ Level 1 Level 2 Level 3 Total ​ ​ (In thousands) Assets: ​ ​ ​ ​ ​ Money-market funds classified as non-current restricted investments ​ $ 1,154 ​ $ — ​ $ — ​ $ 1,154 Money-market funds classified as short-term investments ​ 57,704 ​ — ​ — ​ 57,704 Total ​ $ 58,858 ​ $ — ​ $ — ​ $ 58,858 ​ Cash held in demand deposit accounts of $21.1 million and $3.1 million is excluded from our fair-value hierarchy disclosure as of September 30, 2020 and December 31, 2019, respectively. There were no unrealized gains or losses associated with our investments as of September 30, 2020 or December 31, 2019. The carrying amounts reported in the accompanying Condensed Consolidated Balance Sheets for receivables, accounts payable, other current monetary assets and liabilities approximate fair value. See “Note 6—Unsecured Convertible Senior Notes” for the carrying amount and estimated fair value of our 6.25% Convertible Senior Notes due 2023 .

Line Of Credit

Line Of Credit	9 Months Ended
	Sep. 30, 2020
Line of Credit
Line of Credit	Note 5—Line of Credit We have a Loan and Security Agreement with Silicon Valley Bank, which provides for a $50.0 million revolving line of credit facility (the Line of Credit Agreement). Under the Line of Credit Agreement, we may draw, on a revolving basis, up to the lesser of $50.0 million or 85.0% of our eligible accounts receivable, less certain reserves. Interest on amounts outstanding is payable monthly at the greater of 5.5% and the prime rate. The line of credit is secured by all our assets excluding intellectual property and development program inventories. As of September 30, 2020 and December 31, 2019, we had no outstanding borrowings under the Line of Credit Agreement. ​

Unsecured Convertible Senior No

Unsecured Convertible Senior Notes	9 Months Ended
	Sep. 30, 2020
Unsecured Convertible Senior Notes
Unsecured Convertible Senior Notes	Note 6—Unsecured Convertible Senior Notes Unsecured convertible senior notes outstanding at September 30, 2020 and December 31, 2019 are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of September 30, 2020 ​ 2023 Notes 2026 Notes Total ​ ​ (In thousands) Principal amount ​ $ 95,000 ​ $ 225,030 ​ $ 320,030 Unamortized discount ​ (18,276) ​ (62,591) ​ (80,867) Unamortized issuance costs attributable to liability component ​ (1,583) ​ (4,772) ​ (6,355) Total Convertible Senior Notes, net ​ $ 75,141 ​ $ 157,667 ​ $ 232,808 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of outstanding Convertible Senior Notes (2) ​ $ 89,775 ​ $ 182,043 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount by which the Convertible Senior Notes if-converted value exceeds their principal amount ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity component ​ $ 25,854 ​ $ 63,544 ​ ​ ​ Unamortized issuance costs ​ (837) ​ (1,916) ​ ​ ​ Net carrying amount of equity component (1) ​ $ 25,017 ​ $ 61,628 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2019 ​ 2023 Notes 2026 Notes Total ​ ​ (In thousands) Principal amount ​ $ 210,000 ​ $ — ​ $ 210,000 Unamortized discount ​ (47,660) ​ — ​ (47,660) Unamortized issuance costs attributable to liability component ​ (4,127) ​ — ​ (4,127) Total Convertible Senior Notes, net ​ $ 158,213 ​ $ — ​ $ 158,213 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of outstanding Convertible Senior Notes (2) ​ $ 208,163 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount by which the Convertible Senior Notes if-converted value exceeds their principal amount ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity component ​ $ 57,152 ​ $ — ​ ​ ​ Unamortized issuance costs ​ (1,851) ​ ​ — ​ ​ ​ Net carrying amount of equity component (1) ​ $ 55,301 ​ $ — ​ ​ ​ (1) Included in the condensed consolidated balance sheet within additional paid-in capital (2) The fair value is classified as Level 3 due to the limited trading activity for the Convertible Senior Notes. 2023 Convertible Senior Notes On November 15, 2018, we issued $210.0 million in aggregate principal amount of our 6.25% Convertible Senior Notes (the 2023 Notes). The 2023 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. The 2023 Notes mature on November 15, 2023 unless earlier purchased, redeemed or converted in accordance with their terms. The 2023 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. To reduce the dilutive impact or potential cash expenditure associated with conversion of the 2023 Notes, we entered into a capped call transaction (the 2023 Capped Call), which essentially covers the number of shares of our common stock underlying the 2023 Notes when our common stock is trading between the initial conversion price of $19.22 per share and $28.84 per share. On August 14, 2020, we issued $210.0 million aggregate principal amount of 5.25% Convertible Senior Notes (the 2026 Notes) and used $125.6 million of the net proceeds to repurchase $115.0 million principal amount of the 2023 Notes (see “2026 Convertible Senior Notes” below). The settlement consideration was allocated between the repurchase of the liability and the equity component with the fair value of the liability component estimated to be $103.6 million based on the expected future cash flows associated with the $115.0 million principal amount discounted at a 9.9% effective interest rate. The remaining $22.0 million was accounted for as a repurchase of the equity component, reducing additional paid-in capital. As of the repurchase date of August 14, 2020, the carrying value of the repurchased 2023 Notes, net of unamortized debt discount and issuance costs, was $90.2 million. The difference between the $103.6 million fair value of the 2023 Notes repurchased and the carrying value of $90.2 million resulted in a $13.4 million loss on early extinguishment of debt. After giving effect to the repurchase, the total principal amount outstanding on the 2023 Notes as of August 14, 2020 was $95.0 million. In connection with the repurchase of $115.0 million in principal amount of the 2023 Notes, we entered into a capped call termination contract in August 2020 for approximately 6.0 million underlying shares to unwind a proportionate amount of the 2023 Capped Call. Upon settlement, the Company received $7.5 million in cash and recorded a $0.8 million loss due to the change in fair value of the contract between signing and settlement dates. The proceeds were recorded as an increase in additional paid-in capital and the loss was recorded to other expense in the condensed consolidated statements of operations and comprehensive loss. As of September 30, 2020, approximately 4.9 million shares remained outstanding on the 2023 Capped Call. The following table sets forth total interest expense recognized in connection with the 2023 Notes: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Contractual interest expense ​ $ 2,363 ​ $ 3,281 ​ $ 8,925 ​ $ 9,844 Amortization of debt issuance costs ​ 156 ​ 188 ​ 567 ​ 543 Amortization of debt discount ​ 1,804 ​ 2,167 ​ 6,551 ​ 6,271 Total ​ $ 4,323 ​ $ 5,636 ​ $ 16,043 ​ $ 16,658 ​ 2026 Convertible Senior Notes In August 2020, we issued $210.0 million aggregate principal amount of 5.25% convertible senior notes. In September 2020, an additional $15.0 million aggregate principal amount was issued on the partial exercise of the underwriters’ option, which resulted in an aggregate principal amount outstanding of $225.0 million. The issuance of the notes and use of proceeds are below: ​ ​ ​ ​ ​ ​ (In thousands) 2026 Notes issued ​ $ 225,030 Termination of the 2023 Capped Call contracts related to debt repurchased ​ 7,549 Repurchase of 2023 Notes ​ (125,638) Purchase of 2026 Capped Call ​ (23,223) Issuance costs ​ (6,785) Net proceeds available for corporate use ​ $ 76,933 ​ The 2026 Notes are unsecured and accrue interest at an annual rate of 5.25% per annum, payable semi-annually in arrears on February 15 and August 15 of each year. The 2026 Notes mature on February 15, 2026, unless earlier purchased, redeemed or converted in accordance with their terms. The initial conversion rate is 54.0906 shares of our common stock per $1,000 of note principal (equivalent to an initial conversion price of approximately $18.4875 per share of common stock), which equals approximately 12.2 million shares upon conversion, subject to adjustment in certain circumstances. The 2026 Notes are convertible at the option of the holders on or after November 15, 2025 at any time prior to the close of business on February 12, 2026, the second scheduled trading day immediately before the stated maturity date of February 15, 2026. Additionally, holders may convert their 2026 Notes at their option at specified times prior to the maturity date only if: (1) during any calendar quarter, beginning after September 30, 2020, that the last reported sale price per share of our common stock exceeds 130% of the conversion price of the 2026 Notes for each of at least 20 trading days in the period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter; (2) during the five consecutive business days immediately after any five -consecutive-trading-day period (such five -consecutive-trading-day period, the “measurement period”) in which the trading price per $1,000 principal amount of 2026 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day; (3) there is an occurrence of one or more certain corporate events or distributions of our common stock; or (4) we call the 2026 Notes for redemption. We may elect, at our sole discretion, to convert the 2026 Notes into cash, shares of our common stock or a combination thereof. Subject to the satisfaction of certain conditions, we may redeem in whole or in part the 2026 Notes at our option beginning August 15, 2023 through the 50th scheduled trading day immediately before the maturity date at a cash redemption price equal to the principal amount of the 2026 Notes to be redeemed plus any accrued and unpaid interest to, but excluding, the redemption date. The 2026 Notes are subject to redemption only if certain requirements are satisfied, including that the last reported sale price per share of our common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice and (ii) the trading day immediately before the date we send such notice. In order to reduce the dilutive impact or potential cash expenditure associated with the conversion of the 2026 Notes, we entered into capped call transactions in connection with the initial issuance of the 2026 Notes and at the time of the issuance of additional 2026 Notes upon the underwriters’ partial exercise of their option (collectively, the 2026 Capped Call). The 2026 Capped Call will cover, subject to anti-dilution adjustments substantially similar to those applicable to the 2026 Notes, the number of shares of common stock underlying the 2026 Notes when our common stock is trading within the range of approximately $18.49 and $26.10 . However, should the market price of our common stock exceed the $26.10 cap, then the conversion of the 2026 Notes would have a dilutive impact or may require a cash expenditure to the extent the market price exceeds the cap price. The 2026 Capped Call will expire on various dates over the 50 -trading-day period ranging from December 2, 2025 to February 12, 2026, if not exercised earlier. The 2026 Capped Call is a separate transaction and not part of the terms of the 2026 Notes and was executed separately from the issuance of the 2026 Notes. The amount paid for the 2026 Capped Call was recorded as a reduction to additional paid-in capital in the condensed consolidated balance sheet. We evaluated the accounting for the issuance of the 2026 Notes and concluded that the embedded conversion features meet the requirements for a derivative scope exception for instruments that are both indexed to an entity’s own stock and classified in stockholders’ equity in its balance sheet, and that the cash conversion guidance applies. Therefore, proceeds of $225.0 million are allocated first to the liability component based on the fair value of non-convertible debt with the residual proceeds allocated to the equity component for the conversion features. The Company allocated $6.8 million in issuance costs associated with the 2026 Notes to the liability and equity component in the same proportion as the $225.0 million in proceeds. Further, we concluded the 2026 Capped Call qualifies for a derivative scope exception for instruments that are both indexed to an entity’s own stock and classified in stockholders’ equity in its balance sheet. Consequently, the fair value of the 2026 Capped Call of $23.2 million is classified as equity and will not be subsequently remeasured. In accounting for the issuance of the 2026 Notes, we separated the 2026 Notes into liability and equity components, using an effective interest rate of 12.5% to determine the fair value of the liability component. The following table sets forth interest expense recognized related to the 2026 Notes: ​ ​ ​ ​ ​ ​ Three and Nine ​ ​ Months Ended ​ ​ September 30, 2020 ​ ​ (In thousands) Contractual interest expense ​ $ 1,444 Amortization of debt issuance costs ​ 74 Amortization of debt discount ​ 976 Total ​ $ 2,494 ​ Future minimum payments for the 2023 and 2026 Notes as of September 30, 2020 are as follows: ​ ​ ​ ​ ​ ​ (In thousands) 2020 ​ $ — 2021 ​ — 2022 ​ — 2023 ​ 95,000 2024 ​ — 2025 and thereafter ​ 225,030 Total future minimum payments under the convertible senior notes $ 320,030 ​

Lease Liabilities

Lease Liabilities	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Lease liabilities	Note 7—Leases We have operating leases related to our office and laboratory space and finance leases for certain laboratory and office equipment as follows: ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ (In thousands) Assets ​ ​ ​ ​ ​ Operating lease assets $ 26,116 $ 27,082 Finance lease assets, net 2,150 ​ 2,973 Total lease assets $ 28,266 $ 30,055 ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ Current: ​ ​ ​ ​ ​ Operating leases $ 2,619 $ 2,282 Finance leases 1,135 ​ 1,222 Non-current: ​ ​ ​ ​ ​ Operating leases 28,767 ​ 30,772 Finance leases 950 ​ 1,546 Total lease liabilities $ 33,471 $ 35,822 ​ The components of total lease cost are as follows: ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, ​ 2020 2019 ​ (In thousands) Lease cost ​ ​ Operating lease cost $ 4,540 ​ $ 3,121 Finance lease cost: ​ ​ Amortization 1,039 ​ 984 Interest 224 ​ 248 Variable lease cost 1,715 ​ 1,699 Sublease income (929) ​ (673) Total lease cost $ 6,589 ​ $ 5,379 ​ The supplemental cash flow information related to leases is as follows: ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, ​ 2020 2019 ​ (In thousands) Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ Operating cash flows used for operating leases $ 6,490 ​ $ 4,962 Operating cash flows used for finance leases $ 224 $ 248 Financing cash flows used for finance leases $ 889 $ 813 ​

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 8—Commitments and Contingencies Lease Agreements We lease our office and laboratory space in The Omeros Building under a lease agreement with BMR - 201 Elliott Avenue LLC. The initial term of the lease ends in November 2027, and we have two options to extend the lease term, each by five years. As of September 30, 2020, the remaining aggregate non-cancelable rent payable under the initial term of the lease, excluding common area maintenance and related operating expenses, is $48.2 million. Contracts We have various agreements with third parties that would collectively require payment of termination fees totaling $35.9 million if we had cancelled the work as of September 30, 2020. 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 in connection with clinical development or commercial milestones and/or low single to low double-digit royalties on the net income or net sales of the product. For the three and nine months ended September 30, 2020 and 2019, development milestones were insignificant. We do not owe any royalties on OMIDRIA.

Shareholders' Deficit

Shareholders' Deficit	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Shareholders' Deficit	Note 9—Shareholders’ Deficit Common Stock and Warrants For the nine months ended September 30, 2020, we received proceeds of $5.0 million upon the exercise of stock options which resulted in the issuance of 550,342 shares of common stock. For the nine months ended September 30, 2019, we received proceeds of $5.0 million upon the exercise of stock options which resulted in the issuance of 513,790 shares of common stock. As of September 30, 2020 and December 31, 2019, we had 243,115 warrants outstanding with a weighted average exercise price of $20.68 per share. Underwritten Public Offering of Common Stock On August 14, 2020, we sold 6.9 million shares of our common stock at a public offering price of $14.50 per share. After deducting underwriter discounts and offering expenses, we received net proceeds from the transaction of $93.7 million. Interim Condensed Consolidated Statements of Shareholders’ Deficit The changes in interim balances of the components of our shareholders’ deficit are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ ​ ​ ​ ​ ​ ​ Common ​ Paid-In ​ Accumulated ​ ​ ​ ​ Stock Capital Deficit ​ Total ​ ​ ​ (In thousands) Balance January 1, 2020 ​ $ 542 ​ $ 625,048 ​ $ (734,611) ​ $ (109,021) Exercise of stock options ​ ​ 3 ​ ​ 2,709 ​ ​ — ​ ​ 2,712 Stock-based compensation expense ​ ​ — ​ ​ 3,476 ​ ​ — ​ ​ 3,476 Net loss ​ ​ — ​ ​ — ​ ​ (29,031) ​ ​ (29,031) Balance March 31, 2020 ​ ​ 545 ​ ​ 631,233 ​ ​ (763,642) ​ ​ (131,864) Exercise of stock options ​ ​ — ​ ​ 66 ​ ​ — ​ ​ 66 Stock-based compensation expense ​ ​ — ​ ​ 3,822 ​ ​ — ​ ​ 3,822 Net loss ​ ​ — ​ ​ — ​ ​ (33,294) ​ ​ (33,294) Balance June 30, 2020 ​ ​ 545 ​ ​ 635,121 ​ ​ (796,936) ​ ​ (161,270) Issuance of common stock in direct offering, net of offering costs ​ ​ 69 ​ ​ 93,606 ​ ​ — ​ ​ 93,675 Exercise of stock options ​ ​ 2 ​ ​ 2,198 ​ ​ — ​ ​ 2,200 Stock-based compensation expense ​ ​ — ​ ​ 3,824 ​ ​ — ​ ​ 3,824 Equity component of 2026 Notes, net of issuance costs ​ ​ — ​ ​ 61,628 ​ ​ — ​ ​ 61,628 Purchases of 2026 Capped Calls ​ ​ — ​ ​ (23,223) ​ ​ — ​ ​ (23,223) Equity component of early extinguishment of 2023 Notes ​ ​ — ​ ​ (22,073) ​ ​ — ​ ​ (22,073) Termination of the 2023 Capped Call contracts related to debt repurchased ​ ​ — ​ ​ 8,387 ​ ​ — ​ ​ 8,387 Tax benefit related to issuance of 2026 Notes, net of extinguishment ​ ​ — ​ ​ (12,011) ​ ​ — ​ ​ (12,011) Net loss ​ ​ — ​ ​ — ​ ​ (38,463) ​ ​ (38,463) Balance September 30, 2020 ​ $ 616 ​ $ 747,457 ​ $ (835,399) ​ $ (87,326) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ ​ ​ ​ ​ ​ ​ Common ​ Paid-In ​ Accumulated ​ ​ ​ ​ Stock Capital Deficit ​ Total ​ ​ ​ (In thousands) Balance January 1, 2019 ​ $ 490 ​ $ 549,479 ​ $ (650,125) ​ $ (100,156) Exercise of stock options ​ ​ — ​ ​ 108 ​ ​ — ​ ​ 108 Stock-based compensation expense ​ ​ — ​ ​ 3,374 ​ ​ — ​ ​ 3,374 Net loss ​ ​ — ​ ​ — ​ ​ (24,345) ​ ​ (24,345) Balance March 31, 2019 ​ ​ 490 ​ ​ 552,961 ​ ​ (674,470) ​ ​ (121,019) Exercise of stock options ​ ​ 2 ​ ​ 1,598 ​ ​ — ​ ​ 1,600 Stock-based compensation expense ​ ​ — ​ ​ 3,598 ​ ​ — ​ ​ 3,598 Net loss ​ ​ — ​ ​ — ​ ​ (14,453) ​ ​ (14,453) Balance June 30, 2019 ​ ​ 492 ​ ​ 558,157 ​ ​ (688,923) ​ ​ (130,274) Exercise of stock options ​ ​ 3 ​ ​ 3,323 ​ ​ — ​ ​ 3,326 Stock-based compensation expense ​ ​ — ​ ​ 3,496 ​ ​ — ​ ​ 3,496 Net loss ​ ​ — ​ ​ — ​ ​ (16,463) ​ ​ (16,463) Balance September 30, 2019 ​ $ 495 ​ $ 564,976 ​ $ (705,386) ​ $ (139,915) ​

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2020
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Note 10—Stock-Based Compensation Stock-based compensation expense is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended ​ ​ September 30, ​ September 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Research and development ​ $ 1,636 ​ $ 1,558 ​ $ 4,714 ​ $ 4,698 Selling, general and administrative ​ 2,188 ​ 1,938 ​ 6,408 ​ 5,770 Total ​ $ 3,824 ​ $ 3,496 ​ $ 11,122 ​ $ 10,468 ​ The fair value of each option grant 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 ​ ​ Nine Months Ended ​ ​ September 30, 2020 ​ ​ September 30, 2020 Estimated weighted-average fair value ​ $ 8.21 ​ ​ ​ $ 8.22 ​ Weighted-average assumptions: ​ ​ ​ ​ ​ ​ ​ Expected volatility ​ 82 % ​ ​ 77 % Expected term, in years ​ 6.1 ​ ​ ​ 6.0 ​ Risk-free interest rate ​ 0.58 % ​ ​ 1.10 % Expected dividend yield ​ — % ​ ​ — % ​ Stock option activity for all stock plans and related information is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ Aggregate ​ ​ ​ ​ Exercise ​ Remaining ​ Intrinsic ​ ​ Options ​ Price per ​ Contractual Life ​ Value ​ ​ Outstanding ​ Share ​ (In years) ​ (In thousands) Balance at December 31, 2019 11,207,931 ​ $ 11.72 ​ Granted 2,074,460 ​ 12.36 ​ Exercised (550,342) ​ 9.05 ​ Forfeited (635,433) ​ 11.29 ​ Balance at September 30, 2020 12,096,616 ​ $ 11.98 6.2 ​ $ 3,433 Vested and expected to vest at September 30, 2020 11,689,261 ​ $ 11.93 6.1 ​ $ 3,432 Exercisable at September 30, 2020 8,407,551 ​ $ 11.38 5.1 ​ $ 3,426 ​ As of September 30, 2020, there were 3.7 million unvested options outstanding that will vest over a weighted-average period of 2.6 years and 4.0 million shares were available to grant. The total estimated compensation expense yet to be recognized on outstanding options is $28.0 million.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Note 11—Income Taxes We have a history of losses and therefore have historically not made a provision for income taxes. However, in the quarter ended September 30, 2020, we recorded an income tax benefit of $7.9 million related to the issuance of our 2026 Notes (see —Unsecured

Organization and Significant _2

Organization and Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2020
Accounting Policies [Abstract]
Organization	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, addiction 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	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 intercompany 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 September 30, 2020 and December 31, 2019 and for the three and nine months ended September 30, 2020 and 2019 includes all adjustments, which include normal recurring adjustments, necessary to present fairly our interim financial information. The Condensed Consolidated Balance Sheet at December 31, 2019 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, 2019, which was filed with the U.S. Securities and Exchange Commission (SEC) on March 2, 2020.
Risks and Uncertainties	Risks and Uncertainties In its 2021 outpatient prospective payment system (OPPS) proposed rule, the Centers for Medicare and Medicaid Services (CMS), a part of the Department of Health and Human Services (HHS), confirmed the October 1, 2020 expiration of pass-through reimbursement for OMIDRIA and indicated an intention to package payment for OMIDRIA with payment for the associated surgical procedure in both the hospital outpatient department (HOPD) and ambulatory surgery center (ASC) settings. We are continuing to pursue administrative and legislative avenues to secure separate payment for OMIDRIA; however, we cannot provide assurance that these efforts will be successful. The outbreak of the novel strain of coronavirus (SARS-CoV-2) that causes COVID-19 and the responses to the global pandemic by various governmental authorities, the medical community and others continue to have a significant impact on our business. In March 2020, ASCs and hospitals using OMIDRIA postponed nearly all cataract surgery in response to recommendations from government and medical organizations. As a result, we did not record any sales of OMIDRIA to our wholesalers from March 25 to May 19, 2020. However, by the end of June 2020, the run rate of weekly OMIDRIA sales had recovered to levels approximating those seen prior to the pandemic. Due to the unknown magnitude, duration and outcome of the COVID-19 pandemic, it is not possible to estimate precisely its impact on our business, operations or financial results; however, the impact has been and could continue to be material. As of September 30, 2020, we had cash, cash equivalents and short-term investments of $153.5 million and an accounts receivable-based line of credit that allows us to borrow up to the lesser of $50.0 million or 85% of our accounts receivable borrowing base, less certain reserves. We have incurred losses from operations of $76.8 million for the nine months ended September 30, 2020, and cash used in operating activities was $81.7 million for the nine months ended September 30, 2020. We will continue to incur losses from operating activities until our revenues exceed operating costs and debt service obligations. OMIDRIA pass-through reimbursement from CMS expired on October 1, 2020. If continued separate payment is determined not to be reasonably achievable in the near term, we have developed a commercial strategy that can be quickly implemented to lower the per-vial sales price of OMIDRIA to achieve substantially larger sales volumes. We believe that this approach would result in substantial revenues from OMIDRIA, in part because CMS Medicare Part B beneficiaries only represent approximately 45% of cataract surgery procedures annually. We anticipate narsoplimab for HSCT-TMA will receive FDA approval and will launch in early to mid-2021. Currently we cannot fully predict the timing or the magnitude of narsoplimab revenues, but we believe they will be significant. Execution of our sales and marketing strategies for the launch of narsoplimab for HSCT-TMA is underway. These plans include various milestones at which we commit to incremental activities, providing for flexibility in the timing of costs incurred should the approval of narsoplimab be accelerated or delayed. If warranted, we will adjust the timing and associated costs of our HSCT-TMA launch activities as we advance through the biologics license application (BLA) review and approval process. We plan to continue to fund our operations for at least the next twelve months with our cash and investments on hand, from sales of OMIDRIA and, if FDA approval is granted, from sales of narsoplimab for HSCT-TMA. There is also the possibility that we could generate revenue from sales of narsoplimab for the treatment of COVID-19. In addition, we may utilize funds available under our accounts receivable-based line of credit, which allows us to borrow up to 85% of our available accounts receivable borrowing base, less certain reserves, or $50.0 million, whichever is less. Should it be necessary or determined to be strategically advantageous, we also could pursue debt financings, public and private offerings of our equity securities similar to those we have completed previously, or other strategic transactions, which may include licensing a portion of our existing technology. 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, or implementing other restructuring activities.
Use of Estimates	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 other contingencies. We base our estimates on historical experience and on various other factors, including the impact of the COVID-19 pandemic, that we believe are reasonable under the circumstances; however, actual results could differ from these estimates.
Revenue Recognition	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. 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	Right-of-Use Assets and Related Lease Liabilities We record operating leases 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 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 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.
Income Taxes	Income Taxes Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their tax bases. Deferred tax assets and liabilities are measured using enacted tax rates applied to taxable income in the years in which those temporary differences are expected to be recovered or settled. We recognize the effect of income tax positions only if those positions are more likely than not of being sustained upon an examination. A valuation allowance is established when it is more likely than not that the deferred tax assets will not be realized.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense is recognized for all share-based payments 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.
Recently Adopted Pronouncements	Recently Adopted Pronouncements In June 2016, the Financial Accounting Standards Board 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 adopted the standard on January 1, 2020 and the adoption did not have a material impact on our consolidated financial statements and disclosures. ​ Recent Accounting Pronouncements Not Yet Adopted In August 2020, the Financial Accounting Standards Board Debt—Debt with Conversion Options and Derivatives and Hedging—Contracts in Entity’s Own Equity Derivatives and Hedging convertible debt instrument was issued at a substantial premium. Among other potential impacts, this change is expected to reduce reported interest expense, increase reported net income, and result in a reclassification of certain conversion feature balance sheet amounts from stockholders’ equity to liabilities as it relates to the Company’s convertible senior notes. Additionally, ASU 2020-06 requires the application of the if-converted method to calculate the impact of convertible instruments on diluted earnings per share (EPS), which is consistent with the Company’s accounting treatment under the current standard. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021, with early adoption permitted for fiscal years beginning after December 15, 2020, and can be adopted on either a fully retrospective or modified retrospective basis. The Company is evaluating the impact of this pronouncement on its consolidated financial statements. In December 2019, the Financial Accounting Standards Board Income Taxes

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2020
Earnings Per Share [Abstract]
Calculation of Historical Outstanding Dilutive Securities Not Included in Diluted Loss per Share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ September 30, ​ September 30, ​ 2020 2019 2020 2019 Outstanding options to purchase common stock 1,456,454 3,026,871 ​ 1,777,393 2,829,807 Outstanding warrants to purchase common stock 9,828 18,128 ​ 11,712 16,923 Total potentially dilutive shares excluded from loss per share 1,466,282 3,044,999 ​ 1,789,105 2,846,730

Certain Balance Sheet Accounts

Certain Balance Sheet Accounts (Tables)	9 Months Ended
	Sep. 30, 2020
Receivables [Abstract]
Schedule of accounts receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ ​ (In thousands) Trade receivables, net ​ $ 37,218 ​ $ 35,074 Sublease and other receivables ​ 161 ​ 111 Total accounts receivables, net ​ $ 37,379 ​ $ 35,185 ​
Schedule of Inventory, Current	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ ​ (In thousands) Raw materials $ 79 $ 91 Work-in-progress ​ 797 ​ 338 Finished goods ​ 666 ​ 718 Total inventory $ 1,542 $ 1,147 ​
Property, Plant and Equipment	​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Finance leases ​ $ 5,690 ​ $ 5,474 Laboratory equipment ​ 2,903 ​ 2,844 Computer equipment ​ 985 ​ 921 Office equipment and furniture ​ 625 ​ 625 Total cost ​ 10,203 ​ 9,864 Less accumulated depreciation and amortization ​ (7,253) ​ (6,035) Total property and equipment, net ​ $ 2,950 ​ $ 3,829 ​
Accrued Expenses	​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Sales rebates, fees and discounts ​ $ 10,201 ​ $ 10,870 Contract research and development ​ ​ 8,813 ​ ​ 24,107 Employee compensation ​ 6,415 ​ 3,546 Consulting and professional fees ​ 5,479 ​ 3,610 Interest payable ​ 3,736 ​ 1,640 Clinical trials ​ 1,482 ​ 1,982 Other accrued expenses ​ 822 ​ 872 Total accrued expenses ​ $ 36,948 ​ $ 46,627 ​

Fair-Value Measurements (Tables

Fair-Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2020 ​ Level 1 Level 2 Level 3 Total ​ ​ (In thousands) Assets: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money-market funds classified as non-current restricted investments ​ $ 1,154 ​ $ — ​ $ — ​ $ 1,154 Money-market funds classified as short-term investments ​ 132,448 ​ — ​ — ​ 132,448 Total ​ $ 133,602 ​ $ — ​ $ — ​ $ 133,602 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ Level 1 Level 2 Level 3 Total ​ ​ (In thousands) Assets: ​ ​ ​ ​ ​ Money-market funds classified as non-current restricted investments ​ $ 1,154 ​ $ — ​ $ — ​ $ 1,154 Money-market funds classified as short-term investments ​ 57,704 ​ — ​ — ​ 57,704 Total ​ $ 58,858 ​ $ — ​ $ — ​ $ 58,858 ​

Unsecured Convertible Senior _2

Unsecured Convertible Senior Notes (Tables)	9 Months Ended
	Sep. 30, 2020
Debt Instrument [Line Items]
Summary of unsecured convertible senior notes outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of September 30, 2020 ​ 2023 Notes 2026 Notes Total ​ ​ (In thousands) Principal amount ​ $ 95,000 ​ $ 225,030 ​ $ 320,030 Unamortized discount ​ (18,276) ​ (62,591) ​ (80,867) Unamortized issuance costs attributable to liability component ​ (1,583) ​ (4,772) ​ (6,355) Total Convertible Senior Notes, net ​ $ 75,141 ​ $ 157,667 ​ $ 232,808 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of outstanding Convertible Senior Notes (2) ​ $ 89,775 ​ $ 182,043 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount by which the Convertible Senior Notes if-converted value exceeds their principal amount ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity component ​ $ 25,854 ​ $ 63,544 ​ ​ ​ Unamortized issuance costs ​ (837) ​ (1,916) ​ ​ ​ Net carrying amount of equity component (1) ​ $ 25,017 ​ $ 61,628 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Balance as of December 31, 2019 ​ 2023 Notes 2026 Notes Total ​ ​ (In thousands) Principal amount ​ $ 210,000 ​ $ — ​ $ 210,000 Unamortized discount ​ (47,660) ​ — ​ (47,660) Unamortized issuance costs attributable to liability component ​ (4,127) ​ — ​ (4,127) Total Convertible Senior Notes, net ​ $ 158,213 ​ $ — ​ $ 158,213 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value of outstanding Convertible Senior Notes (2) ​ $ 208,163 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amount by which the Convertible Senior Notes if-converted value exceeds their principal amount ​ $ — ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Equity component ​ $ 57,152 ​ $ — ​ ​ ​ Unamortized issuance costs ​ (1,851) ​ ​ — ​ ​ ​ Net carrying amount of equity component (1) ​ $ 55,301 ​ $ — ​ ​ ​ (1) Included in the condensed consolidated balance sheet within additional paid-in capital (2) The fair value is classified as Level 3 due to the limited trading activity for the Convertible Senior Notes.
Schedule of future minimum payments of debt	​ ​ ​ ​ ​ ​ (In thousands) 2020 ​ $ — 2021 ​ — 2022 ​ — 2023 ​ 95,000 2024 ​ — 2025 and thereafter ​ 225,030 Total future minimum payments under the convertible senior notes $ 320,030
2023 Convertible Senior Notes
Debt Instrument [Line Items]
Schedule of total interest expense recognized	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Contractual interest expense ​ $ 2,363 ​ $ 3,281 ​ $ 8,925 ​ $ 9,844 Amortization of debt issuance costs ​ 156 ​ 188 ​ 567 ​ 543 Amortization of debt discount ​ 1,804 ​ 2,167 ​ 6,551 ​ 6,271 Total ​ $ 4,323 ​ $ 5,636 ​ $ 16,043 ​ $ 16,658
2026 Convertible Senior Notes
Debt Instrument [Line Items]
Schedule of total interest expense recognized	​ ​ ​ ​ ​ ​ Three and Nine ​ ​ Months Ended ​ ​ September 30, 2020 ​ ​ (In thousands) Contractual interest expense ​ $ 1,444 Amortization of debt issuance costs ​ 74 Amortization of debt discount ​ 976 Total ​ $ 2,494
Summary of issuance of the notes and use of proceeds	​ ​ ​ ​ ​ ​ (In thousands) 2026 Notes issued ​ $ 225,030 Termination of the 2023 Capped Call contracts related to debt repurchased ​ 7,549 Repurchase of 2023 Notes ​ (125,638) Purchase of 2026 Capped Call ​ (23,223) Issuance costs ​ (6,785) Net proceeds available for corporate use ​ $ 76,933

Lease Liabilities (Tables)

Lease Liabilities (Tables)	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Schedule of lease-related assets and liabilities recorded on the balance sheet	​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2020 2019 ​ (In thousands) Assets ​ ​ ​ ​ ​ Operating lease assets $ 26,116 $ 27,082 Finance lease assets, net 2,150 ​ 2,973 Total lease assets $ 28,266 $ 30,055 ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ Current: ​ ​ ​ ​ ​ Operating leases $ 2,619 $ 2,282 Finance leases 1,135 ​ 1,222 Non-current: ​ ​ ​ ​ ​ Operating leases 28,767 ​ 30,772 Finance leases 950 ​ 1,546 Total lease liabilities $ 33,471 $ 35,822 ​
Schedule of lease costs	​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, ​ 2020 2019 ​ (In thousands) Lease cost ​ ​ Operating lease cost $ 4,540 ​ $ 3,121 Finance lease cost: ​ ​ Amortization 1,039 ​ 984 Interest 224 ​ 248 Variable lease cost 1,715 ​ 1,699 Sublease income (929) ​ (673) Total lease cost $ 6,589 ​ $ 5,379 ​
Schedule of supplemental cash flow information	​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ September 30, ​ 2020 2019 ​ (In thousands) Cash paid for amounts included in the measurement of lease liabilities ​ ​ ​ ​ ​ Operating cash flows used for operating leases $ 6,490 ​ $ 4,962 Operating cash flows used for finance leases $ 224 $ 248 Financing cash flows used for finance leases $ 889 $ 813

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2020
Equity [Abstract]
Schedule of Stockholders Equity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ ​ ​ ​ ​ ​ ​ Common ​ Paid-In ​ Accumulated ​ ​ ​ ​ Stock Capital Deficit ​ Total ​ ​ ​ (In thousands) Balance January 1, 2020 ​ $ 542 ​ $ 625,048 ​ $ (734,611) ​ $ (109,021) Exercise of stock options ​ ​ 3 ​ ​ 2,709 ​ ​ — ​ ​ 2,712 Stock-based compensation expense ​ ​ — ​ ​ 3,476 ​ ​ — ​ ​ 3,476 Net loss ​ ​ — ​ ​ — ​ ​ (29,031) ​ ​ (29,031) Balance March 31, 2020 ​ ​ 545 ​ ​ 631,233 ​ ​ (763,642) ​ ​ (131,864) Exercise of stock options ​ ​ — ​ ​ 66 ​ ​ — ​ ​ 66 Stock-based compensation expense ​ ​ — ​ ​ 3,822 ​ ​ — ​ ​ 3,822 Net loss ​ ​ — ​ ​ — ​ ​ (33,294) ​ ​ (33,294) Balance June 30, 2020 ​ ​ 545 ​ ​ 635,121 ​ ​ (796,936) ​ ​ (161,270) Issuance of common stock in direct offering, net of offering costs ​ ​ 69 ​ ​ 93,606 ​ ​ — ​ ​ 93,675 Exercise of stock options ​ ​ 2 ​ ​ 2,198 ​ ​ — ​ ​ 2,200 Stock-based compensation expense ​ ​ — ​ ​ 3,824 ​ ​ — ​ ​ 3,824 Equity component of 2026 Notes, net of issuance costs ​ ​ — ​ ​ 61,628 ​ ​ — ​ ​ 61,628 Purchases of 2026 Capped Calls ​ ​ — ​ ​ (23,223) ​ ​ — ​ ​ (23,223) Equity component of early extinguishment of 2023 Notes ​ ​ — ​ ​ (22,073) ​ ​ — ​ ​ (22,073) Termination of the 2023 Capped Call contracts related to debt repurchased ​ ​ — ​ ​ 8,387 ​ ​ — ​ ​ 8,387 Tax benefit related to issuance of 2026 Notes, net of extinguishment ​ ​ — ​ ​ (12,011) ​ ​ — ​ ​ (12,011) Net loss ​ ​ — ​ ​ — ​ ​ (38,463) ​ ​ (38,463) Balance September 30, 2020 ​ $ 616 ​ $ 747,457 ​ $ (835,399) ​ $ (87,326) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ ​ ​ ​ ​ ​ ​ Common ​ Paid-In ​ Accumulated ​ ​ ​ ​ Stock Capital Deficit ​ Total ​ ​ ​ (In thousands) Balance January 1, 2019 ​ $ 490 ​ $ 549,479 ​ $ (650,125) ​ $ (100,156) Exercise of stock options ​ ​ — ​ ​ 108 ​ ​ — ​ ​ 108 Stock-based compensation expense ​ ​ — ​ ​ 3,374 ​ ​ — ​ ​ 3,374 Net loss ​ ​ — ​ ​ — ​ ​ (24,345) ​ ​ (24,345) Balance March 31, 2019 ​ ​ 490 ​ ​ 552,961 ​ ​ (674,470) ​ ​ (121,019) Exercise of stock options ​ ​ 2 ​ ​ 1,598 ​ ​ — ​ ​ 1,600 Stock-based compensation expense ​ ​ — ​ ​ 3,598 ​ ​ — ​ ​ 3,598 Net loss ​ ​ — ​ ​ — ​ ​ (14,453) ​ ​ (14,453) Balance June 30, 2019 ​ ​ 492 ​ ​ 558,157 ​ ​ (688,923) ​ ​ (130,274) Exercise of stock options ​ ​ 3 ​ ​ 3,323 ​ ​ — ​ ​ 3,326 Stock-based compensation expense ​ ​ — ​ ​ 3,496 ​ ​ — ​ ​ 3,496 Net loss ​ ​ — ​ ​ — ​ ​ (16,463) ​ ​ (16,463) Balance September 30, 2019 ​ $ 495 ​ $ 564,976 ​ $ (705,386) ​ $ (139,915)

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2020
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Nine Months Ended ​ ​ September 30, ​ September 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Research and development ​ $ 1,636 ​ $ 1,558 ​ $ 4,714 ​ $ 4,698 Selling, general and administrative ​ 2,188 ​ 1,938 ​ 6,408 ​ 5,770 Total ​ $ 3,824 ​ $ 3,496 ​ $ 11,122 ​ $ 10,468 ​
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ ​ Nine Months Ended ​ ​ September 30, 2020 ​ ​ September 30, 2020 Estimated weighted-average fair value ​ $ 8.21 ​ ​ ​ $ 8.22 ​ Weighted-average assumptions: ​ ​ ​ ​ ​ ​ ​ Expected volatility ​ 82 % ​ ​ 77 % Expected term, in years ​ 6.1 ​ ​ ​ 6.0 ​ Risk-free interest rate ​ 0.58 % ​ ​ 1.10 % Expected dividend yield ​ — % ​ ​ — %
Schedule of Stock Option Activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted- ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ Aggregate ​ ​ ​ ​ Exercise ​ Remaining ​ Intrinsic ​ ​ Options ​ Price per ​ Contractual Life ​ Value ​ ​ Outstanding ​ Share ​ (In years) ​ (In thousands) Balance at December 31, 2019 11,207,931 ​ $ 11.72 ​ Granted 2,074,460 ​ 12.36 ​ Exercised (550,342) ​ 9.05 ​ Forfeited (635,433) ​ 11.29 ​ Balance at September 30, 2020 12,096,616 ​ $ 11.98 6.2 ​ $ 3,433 Vested and expected to vest at September 30, 2020 11,689,261 ​ $ 11.93 6.1 ​ $ 3,432 Exercisable at September 30, 2020 8,407,551 ​ $ 11.38 5.1 ​ $ 3,426 ​

Organization and Significant _3

Organization and Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2020USD ($)segment	Sep. 30, 2019USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | segment			1
Cash, cash equivalents and short-term investments	$ 153,500		$ 153,500
Operating loss	25,428	$ 11,101	76,785	$ 39,676
Net cash used in operating activities			$ 81,679	$ 37,059
Annual cataract surgery procedures to CMS Medicare Part B beneficiaries (as a percent)			45.00%
Line of Credit Agreement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Maximum borrowing capacity	$ 50,000		$ 50,000
Borrowing option - percentage of eligible accounts receivable	85.00%		85.00%

Net Loss Per Share (Details)

Net Loss Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding dilutive securities not included in diluted loss per share calculation	1,466,282	3,044,999	1,789,105	2,846,730
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	1,456,454	3,026,871	1,777,393	2,829,807
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	9,828	18,128	11,712	16,923

Certain Balance Sheet Account_2

Certain Balance Sheet Accounts - Accounts Receivable, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Trade receivables, net	$ 37,218	$ 35,074
Sublease and other receivables	161	111
Total accounts receivables, net	37,379	35,185
Chargeback and product return allowances	$ 8,700
Chargeback allowances		$ 1,600

Certain Balance Sheet Account_3

Certain Balance Sheet Accounts - Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 79	$ 91
Work-in-progress	797	338
Finished goods	666	718
Total inventory	$ 1,542	$ 1,147

Certain Balance Sheet Account_4

Certain Balance Sheet Accounts - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Total cost	$ 10,203		$ 10,203		$ 9,864
Less accumulated depreciation and amortization	(7,253)		(7,253)		(6,035)
Total property and equipment, net	2,950		2,950		3,829
Depreciation and amortization	400	$ 400	1,218	$ 1,262
Finance leases
Property, Plant and Equipment [Line Items]
Total cost	5,690		5,690		5,474
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total cost	2,903		2,903		2,844
Computer equipment
Property, Plant and Equipment [Line Items]
Total cost	985		985		921
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Total cost	$ 625		$ 625		$ 625

Certain Balance Sheet Account_5

Certain Balance Sheet Accounts - Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Contract research and development	$ 8,813	$ 24,107
Sales rebates, fees and discounts	10,201	10,870
Employee compensation	6,415	3,546
Consulting and professional fees	5,479	3,610
Interest payable	3,736	1,640
Clinical trials	1,482	1,982
Other accrued expenses	822	872
Total accrued expenses	$ 36,948	$ 46,627

Fair-Value Measurements - Recur

Fair-Value Measurements - Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds classified as non-current restricted investments	$ 1,154	$ 1,154
Money-market funds classified as short-term investments	132,448	57,704
Fair Value, Measurements, Recurring | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds classified as non-current restricted investments	1,154	1,154
Money-market funds classified as short-term investments	132,448	57,704
Total	133,602	58,858
Fair Value, Measurements, Recurring | Level 1 | Money Market Funds
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Money-market funds classified as non-current restricted investments	1,154	1,154
Money-market funds classified as short-term investments	132,448	57,704
Total	$ 133,602	$ 58,858

Fair-Value Measurements - Narra

Fair-Value Measurements - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Nov. 15, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 21,075	$ 3,084
Unrealized gain (loss) on investments	$ 0	$ 0
2023 Convertible Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate (as a percent)			6.25%

Line of Credit (Details)

Line of Credit (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument
Loss on early extinguishment of debt	$ 13,374	$ 13,374
Outstanding borrowings	232,808	232,808	$ 158,213
Line of Credit Agreement
Debt Instrument
Maximum borrowing capacity	$ 50,000	$ 50,000
Borrowing option - percentage of eligible accounts receivable	85.00%	85.00%
Outstanding borrowings	$ 0	$ 0	$ 0
Prime Rate | Line of Credit Agreement
Debt Instrument
Interest rate (as a percent)	5.50%	5.50%

Unsecured Convertible Senior _3

Unsecured Convertible Senior Notes - Unsecured convertible senior notes outstanding (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Aug. 14, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 320,030		$ 210,000
Unamortized discount	(80,867)		(47,660)
Unamortized issuance costs attributable to principal amount	(6,355)		(4,127)
Total Convertible Senior Notes, net	232,808		158,213
2023 Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	95,000	$ 95,000	210,000
Unamortized discount	(18,276)		(47,660)
Unamortized issuance costs attributable to principal amount	(1,583)		(4,127)
Total Convertible Senior Notes, net	75,141		158,213
Fair value of outstanding Convertible Senior Notes (2)	89,775		208,163
Equity component	25,854		57,152
Unamortized issuance costs	(837)		(1,851)
Net carrying amount of equity component (1)	25,017		$ 55,301
2026 Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	225,030
Unamortized discount	(62,591)
Unamortized issuance costs attributable to principal amount	(4,772)
Total Convertible Senior Notes, net	157,667
Fair value of outstanding Convertible Senior Notes (2)	182,043
Equity component	63,544
Unamortized issuance costs	(1,916)
Net carrying amount of equity component (1)	$ 61,628

Unsecured Convertible Senior _4

Unsecured Convertible Senior Notes - 2023 Convertible Senior Notes (Details) $ / shares in Units, shares in Millions	Aug. 14, 2020USD ($)shares	Nov. 15, 2018USD ($)$ / shares	Sep. 30, 2020USD ($)shares	Sep. 30, 2020USD ($)shares	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Adjustments to additional paid-in capital due to repurchase of the equity component			$ 22,073,000
Loss on early extinguishment of debt			13,374,000	$ 13,374,000
Principal amount			320,030,000	320,030,000	$ 210,000,000
Proceeds from termination of capped call contracts				7,549,000
2023 Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount		$ 210,000,000
Interest rate (as a percent)		6.25%
Conversion rate		0.0520183
Value used in calculation of conversion rate		$ 1,000
Conversion price | $ / shares		$ 19.22
Proceeds from debt issuance	$ 125,600,000
Principal amount of debt repurchased	115,000,000
Fair value of the liability component	$ 103,600,000
Effective interest rate (as a percent)	9.90%
Adjustments to additional paid-in capital due to repurchase of the equity component	$ 22,000,000
Amount outstanding	90,200,000
Loss on early extinguishment of debt	13,400,000
Principal amount	$ 95,000,000		$ 95,000,000	$ 95,000,000	$ 210,000,000
Number of underlying shares | shares	6
Proceeds from termination of capped call contracts	$ 7,500,000
Settlement loss upon termination of cap call contract	$ 800,000
Number of shares outstanding on the 2023 Capped Call | shares			4.9	4.9
2023 Convertible Senior Notes | Minimum
Debt Instrument [Line Items]
Conversion price | $ / shares		19.22
2023 Convertible Senior Notes | Maximum
Debt Instrument [Line Items]
Conversion price | $ / shares		$ 28.84

Unsecured Convertible Senior _5

Unsecured Convertible Senior Notes - 2026 Convertible Senior Notes (Details) $ / shares in Units, shares in Millions	Aug. 14, 2020USD ($)D$ / sharesshares	Sep. 30, 2020USD ($)	Dec. 31, 2019USD ($)
Debt Instrument [Line Items]
Aggregate principal amount outstanding		$ 320,030,000	$ 210,000,000
Termination of the 2023 Capped Call contracts related to debt repurchased		7,549,000
Repurchase of 2023 Notes		(125,638,000)
2026 Convertible Senior Notes
Debt Instrument [Line Items]
Principal amount	$ 210,000,000	$ 15,000,000
Interest rate (as a percent)	5.25%	5.25%
Aggregate principal amount outstanding		$ 225,030,000
2026 Notes issued	$ 225,030,000
Termination of the 2023 Capped Call contracts related to debt repurchased	7,549,000
Repurchase of 2023 Notes	(125,638,000)
Purchase of 2026 Capped Call	(23,223,000)
Issuance costs	(6,785,000)
Net proceeds available for corporate use	$ 76,933,000
Conversion rate	0.0540906
Value used in calculation of conversion rate	$ 1,000
Shares upon conversion | shares	12.2
Conversion price | $ / shares	$ 18.4875
Capped Call Transactions, Threshold Trading Day Period	50 days
Fair value of equity component	$ 23,200,000
Effective interest rate (as a percent)	12.50%
2026 Convertible Senior Notes | Debt Conversion, After September 30, 2020
Debt Instrument [Line Items]
Stock price trigger (as a percent)	130.00%
Trading days, number | D	20
Consecutive trading days, period | D	30
Consecutive business days, period	5 days
Consecutive trading-day period	5 days
Maximum product of the closing sale price of shares of the Company's common stock and the applicable conversion rate for such trading day (as a percent)	98.00%
2026 Convertible Senior Notes | Debt Conversion, On Or After August 15, 2023
Debt Instrument [Line Items]
Stock price trigger (as a percent)	130.00%
Trading days, number | D	20
Consecutive trading days, period | D	30
2026 Convertible Senior Notes | Minimum
Debt Instrument [Line Items]
Conversion price | $ / shares	$ 18.49
2026 Convertible Senior Notes | Maximum
Debt Instrument [Line Items]
Conversion price | $ / shares	$ 26.10

Unsecured Convertible Senior _6

Unsecured Convertible Senior Notes - Interest expense recognized (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
2023 Convertible Senior Notes
Interest Expense, Debt [Abstract]
Contractual interest expense	$ 2,363	$ 3,281	$ 8,925	$ 9,844
Amortization of debt issuance costs	156	188	567	543
Amortization of debt discount	1,804	2,167	6,551	6,271
Total	4,323	$ 5,636	$ 16,043	$ 16,658
2026 Convertible Senior Notes
Interest Expense, Debt [Abstract]
Contractual interest expense	1,444
Amortization of debt issuance costs	74
Amortization of debt discount	976
Total	$ 2,494

Unsecured Convertible Senior _7

Unsecured Convertible Senior Notes - Future minimum payments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Long-term Debt, Fiscal Year Maturity [Abstract]
Total future minimum payments under the convertible senior notes	$ 320,030	$ 210,000
2023 and 2026 Convertible Senior Notes
Long-term Debt, Fiscal Year Maturity [Abstract]
2023	95,000
2025 and thereafter	225,030
Total future minimum payments under the convertible senior notes	$ 320,030

Lease Liabilities (Details)

Lease Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Classification on the Balance Sheet
Operating lease assets	$ 26,116		$ 27,082
Finance lease assets, net	2,150		2,973
Total lease assets	28,266		30,055
Operating leases, current	2,619		2,282
Finance leases, current	1,135		1,222
Operating leases, non-current	28,767		30,772
Finance leases, non-current	950		1,546
Total lease liabilities	33,471		$ 35,822
Lease cost
Operating lease cost	4,540	$ 3,121
Amortization	1,039	984
Interest	224	248
Variable lease cost	1,715	1,699
Sublease income	(929)	(673)
Total lease cost	6,589	5,379
Operating cash flows used for operating leases	6,490	4,962
Operating cash flows used for finance leases	224	248
Financing cash flows used for finance leases	$ 889	$ 813

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)Options
Commitments and Contingencies Disclosure [Abstract]
Lessee, Operating Lease, Existence of Option to Extend	true
Number of options to extend lease | Options	2
Option to extend, lease period	5 years
Operating expenses	$ 48.2
Contract termination fees	$ 35.9

Shareholders' Deficit - Narrati

Shareholders' Deficit - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Aug. 14, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Class of Warrant or Right [Line Items]
Proceeds upon exercise of stock options		$ 4,978	$ 5,034
Issuance of common stock upon exercise of stock options (in shares)		550,342	513,790
Sale of common stock (in shares)	6,900,000
Sale price per share (in dollars per share)	$ 14.50
Proceeds from issuance of common stock, net	$ 93,700	$ 93,675
Outstanding warrants to purchase common stock
Class of Warrant or Right [Line Items]
Warrants outstanding		243,115		243,115
Warrant exercise price (in USD per share)		$ 20.68		$ 20.68

Shareholders' Deficit- Equity T

Shareholders' Deficit- Equity Table (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Class of Stock [Line Items]
Balance	$ (161,270)	$ (131,864)	$ (109,021)	$ (130,274)	$ (121,019)	$ (100,156)	$ (109,021)	$ (100,156)
Issuance of common stock in direct offering, net of offering costs	93,675
Exercise of stock options	2,200	66	2,712	3,326	1,600	108
Stock-based compensation expense	3,824	3,822	3,476	3,496	3,598	3,374
Equity component of 2026 Notes, net of issuance costs	61,628
Purchases of 2026 Capped Calls	(23,223)
Equity component of early extinguishment of 2023 Notes	(22,073)
Termination of the 2023 Capped Call contracts related to debt repurchased	8,387
Tax benefit related to issuance of 2026 Notes, net of extinguishment	(12,011)
Net loss	(38,463)	(33,294)	(29,031)	(16,463)	(14,453)	(24,345)	(100,788)	(55,261)
Balance	(87,326)	(161,270)	(131,864)	(139,915)	(130,274)	(121,019)	(87,326)	(139,915)
Common Stock [Member]
Class of Stock [Line Items]
Balance	545	545	542	492	490	490	542	490
Issuance of common stock in direct offering, net of offering costs	69
Exercise of stock options	2		3	3	2
Balance	616	545	545	495	492	490	616	495
Additional Paid-in Capital [Member]
Class of Stock [Line Items]
Balance	635,121	631,233	625,048	558,157	552,961	549,479	625,048	549,479
Issuance of common stock in direct offering, net of offering costs	93,606
Exercise of stock options	2,198	66	2,709	3,323	1,598	108
Stock-based compensation expense	3,824	3,822	3,476	3,496	3,598	3,374
Equity component of 2026 Notes, net of issuance costs	61,628
Purchases of 2026 Capped Calls	(23,223)
Equity component of early extinguishment of 2023 Notes	(22,073)
Termination of the 2023 Capped Call contracts related to debt repurchased	8,387
Tax benefit related to issuance of 2026 Notes, net of extinguishment	(12,011)
Balance	747,457	635,121	631,233	564,976	558,157	552,961	747,457	564,976
Retained Earnings [Member]
Class of Stock [Line Items]
Balance	(796,936)	(763,642)	(734,611)	(688,923)	(674,470)	(650,125)	(734,611)	(650,125)
Net loss	(38,463)	(33,294)	(29,031)	(16,463)	(14,453)	(24,345)
Balance	$ (835,399)	$ (796,936)	$ (763,642)	$ (705,386)	$ (688,923)	$ (674,470)	$ (835,399)	$ (705,386)

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 3,824	$ 3,496	$ 11,122	$ 10,468
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,636	1,558	4,714	4,698
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 2,188	$ 1,938	$ 6,408	$ 5,770

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of Employee Option Grant Estimated on Date of Grant (Details) - Outstanding options to purchase common stock - $ / shares	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Estimated weighted-average fair value (USD per share)	$ 8.21	$ 8.22
Weighted Average
Weighted-average assumptions
Expected volatility	82.00%	77.00%
Expected term, in years	6 years 1 month 6 days	6 years
Risk-free interest rate	0.58%	1.10%
Expected dividend yield	0.00%	0.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity and Related Information (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Options Outstanding
Beginning balance (shares)	11,207,931
Granted (shares)	2,074,460
Exercised (shares)	(550,342)	(513,790)
Forfeited (shares)	(635,433)
Ending balance (shares)	12,096,616
Vested and expected to vest (shares)	11,689,261
Exercisable (shares)	8,407,551
Weighted-Average Exercise Price per Share
Beginning balance (USD per share)	$ 11.72
Granted (USD per share)	12.36
Exercised (USD per share)	9.05
Forfeited (USD per share)	11.29
Ending balance (USD per share)	11.98
Vested and expected to vest (USD per share)	11.93
Exercisable (USD per share)	$ 11.38
Weighted- Average Remaining Contractual Life
Balance (in years)	6 years 2 months 12 days
Vested and expected to vest (in years)	6 years 1 month 6 days
Exercisable (in years)	5 years 1 month 6 days
Aggregate Intrinsic Value
Balance	$ 3,433
Vested and expected to vest	3,432
Exercisable	$ 3,426

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - Outstanding options to purchase common stock shares in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2020USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award
Unvested options outstanding (shares)	3.7
Period for recognition	2 years 7 months 6 days
Shares available for future grants (shares)	4
Unrecognized compensation expense | $	$ 28

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income tax benefit	$ 7,854	$ 7,854