Stemline Therapeutics (STML) 10-Q 6 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 05, 2019
Document and Entity Information
Document Type	10-Q
Document Period End Date	Jun. 30, 2019
Entity Registrant Name	STEMLINE THERAPEUTICS INC
Entity Common Stock, Shares Outstanding		43,955,624
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001264587
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Amendment Flag	false

Balance Sheets

Balance Sheets - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 16,965,619	$ 9,443,667
Short-term investments	86,918,164	50,662,189
Accounts receivable	15,093,121
Inventories	3,655,017
Prepaid expenses and other current assets	3,596,436	2,952,996
Total current assets	126,228,357	63,058,852
Property and equipment, net	238,729	222,413
Right-of-use asset, net	1,469,714
Other assets	212,305	212,305
Total assets	128,149,105	63,493,570
Current liabilities:
Accounts payable and accrued expenses	25,748,958	21,153,062
Right-of-use liability - current portion	1,042,526
Other current liabilities	6,142	65,862
Total current liabilities	26,797,626	21,218,924
Right-of-use liability	550,496
Other liabilities	9,496	72,591
Total liabilities	27,357,618	21,291,515
Stockholders' equity:
Preferred stock $0.0001 par value, 5,000,000 shares authorized, none issued and outstanding at June 30, 2019 and December 31, 2018
Common stock $0.0001 par value, 83,750,000 shares authorized at June 30, 2019 and 53,750,000 shares authorized at December 31, 2018. 43,875,679 shares issued and outstanding at June 30, 2019 and 31,943,186 shares issued and outstanding at December 31, 2018	4,388	3,194
Additional paid-in capital	434,071,363	331,343,484
Accumulated other comprehensive income (loss)	52,488	(56,559)
Accumulated deficit	(333,336,752)	(289,088,064)
Total stockholders' equity	100,791,487	42,202,055
Total liabilities and stockholders' equity	$ 128,149,105	$ 63,493,570

Balance Sheets (Parenthetical)

Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2019	Dec. 31, 2018
Balance Sheets
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	83,750,000	53,750,000
Common stock, shares issued	43,875,679	31,943,186
Common stock, shares outstanding	43,875,679	31,943,186

Statements of Operations

Statements of Operations - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Operating expenses:
Cost of goods sold	$ 583,159		$ 668,888
Research and development	10,891,394	$ 11,184,064	27,845,216	$ 23,892,122
Selling, general and administrative	19,002,508	8,622,616	34,956,475	14,561,216
Total operating expenses	30,477,061	19,806,680	63,470,579	38,453,338
Loss from operations	(17,470,352)	(19,306,680)	(45,415,280)	(37,953,338)
Other expense	(262)	(123)	(4,878)	(4,020)
Interest income	610,692	378,100	1,149,276	611,902
Net loss before income taxes	(16,859,922)	(18,928,703)	(44,270,882)	(37,345,456)
Income tax benefit	18,500		22,194	0
Net loss	$ (16,841,422)	$ (18,928,703)	$ (44,248,688)	$ (37,345,456)
Net loss per common share:
Basic and Diluted (in dollars per share)	$ (0.42)	$ (0.66)	$ (1.14)	$ (1.34)
Weighted-average shares outstanding:
Basic and Diluted (in shares)	40,108,267	28,567,982	38,836,664	27,851,707
Product
Revenue:
Revenue	$ 13,006,709		$ 18,055,299
Grant
Revenue:
Revenue		$ 500,000		$ 500,000

Statements of Comprehensive Los

Statements of Comprehensive Loss - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statements of Comprehensive Loss
Net loss	$ (16,841,422)	$ (18,928,703)	$ (44,248,688)	$ (37,345,456)
Other comprehensive gain (loss):
Unrealized gain on investments, net of tax	79,649	27,404	104,723	19,088
Reclassification adjustment for loss on investments included in net loss			4,324	3,897
Other comprehensive gain	79,649	27,404	109,047	22,985
Comprehensive loss	$ (16,761,773)	$ (18,901,299)	$ (44,139,641)	$ (37,322,471)

Statement of Stockholders' Equi

Statement of Stockholders' Equity - USD ($)	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Total
Balance at Dec. 31, 2017	$ 2,531	$ 251,489,546	$ (145,958)	$ (204,275,690)	$ 47,070,429
Balance (in shares) at Dec. 31, 2017	25,313,595
Increase (Decrease) in Stockholders' Equity
Restricted stock grants	$ 74	(74)
Restricted stock grants (in shares)	739,532
Forfeiture of restricted stock grants	$ (4)	4
Forfeiture of restricted stock grants (in shares)	(40,562)
Stock-based compensation expense		5,612,068			5,612,068
Adoption of accounting standard update related to stock compensation accounting (ASU 2018-07) | ASU 2018-07		(211,991)		211,991
Employee Stock Purchase Plan compensation expense		25,350			25,350
Issuance of common stock in connection with the ESPP	$ 2	117,218			117,220
Issuance of common stock in connection with the ESPP (in shares)	15,671
Issuance of common stock in connection with the exercise of stock options	$ 16	1,533,307			1,533,323
Issuance of common stock in connection with the exercise of stock options (in shares)	161,060
Issuance of common stock in connection with the exercise of warrants	$ 3	352,527			352,530
Issuance of common stock in connection with the exercise of warrants (in shares)	30,830
Issuance of common stock in connection with secondary/follow-on public offering, net	$ 470	63,968,347			63,968,817
Issuance of common stock in connection with secondary/follow-on public offering, net (in shares)	4,697,579
Net loss				(37,345,456)	(37,345,456)
Other comprehensive income, net of tax			22,985		22,985
Balance at Jun. 30, 2018	$ 3,092	322,886,302	(122,973)	(241,409,155)	81,357,266
Balance (in shares) at Jun. 30, 2018	30,917,705
Balance at Mar. 31, 2018	$ 3,022	310,857,448	(150,377)	(222,692,443)	88,017,650
Balance (in shares) at Mar. 31, 2018	30,216,530
Increase (Decrease) in Stockholders' Equity
Restricted stock grants	$ 20	(20)
Restricted stock grants (in shares)	198,278
Forfeiture of restricted stock grants	$ (4)	4
Forfeiture of restricted stock grants (in shares)	(40,562)
Stock-based compensation expense		3,405,641			3,405,641
Adoption of accounting standard update related to stock compensation accounting (ASU 2018-07) | ASU 2018-07		(211,991)		211,991
Employee Stock Purchase Plan compensation expense		6,474			6,474
Issuance of common stock in connection with the ESPP	$ 1	67,477			67,478
Issuance of common stock in connection with the ESPP (in shares)	9,021
Issuance of common stock in connection with the exercise of stock options	$ 9	443,398			443,407
Issuance of common stock in connection with the exercise of stock options (in shares)	91,859
Issuance of common stock in connection with secondary/follow-on public offering, net	$ 44	8,317,871			8,317,915
Issuance of common stock in connection with secondary/follow-on public offering, net (in shares)	442,579
Net loss				(18,928,703)	(18,928,703)
Other comprehensive income, net of tax			27,404		27,404
Balance at Jun. 30, 2018	$ 3,092	322,886,302	(122,973)	(241,409,155)	81,357,266
Balance (in shares) at Jun. 30, 2018	30,917,705
Balance at Dec. 31, 2018	$ 3,194	331,343,484	(56,559)	(289,088,064)	42,202,055
Balance (in shares) at Dec. 31, 2018	31,943,186
Increase (Decrease) in Stockholders' Equity
Stock award - in-licensing	$ 4	500,005			500,009
Stock award - in-licensing (in shares)	43,822
Restricted stock grants	$ 163	(163)
Restricted stock grants (in shares)	1,623,471
Forfeiture of restricted stock grants	$ (4)	4
Forfeiture of restricted stock grants (in shares)	(45,096)
Stock-based compensation expense		15,517,821			15,517,821
Employee Stock Purchase Plan compensation expense		70,353			70,353
Issuance of common stock in connection with the ESPP	$ 1	128,769			128,770
Issuance of common stock in connection with the ESPP (in shares)	13,353
Issuance of common stock in connection with the exercise of stock options	$ 7	293,483			293,490
Issuance of common stock in connection with the exercise of stock options (in shares)	74,721
Issuance of common stock in connection with secondary/follow-on public offering, net	$ 1,023	86,217,607			86,218,630
Issuance of common stock in connection with secondary/follow-on public offering, net (in shares)	10,222,222
Net loss				(44,248,688)	(44,248,688)
Other comprehensive income, net of tax			109,047		109,047
Balance at Jun. 30, 2019	$ 4,388	434,071,363	52,488	(333,336,752)	100,791,487
Balance (in shares) at Jun. 30, 2019	43,875,679
Balance at Mar. 31, 2019	$ 4,358	425,410,295	(27,161)	(316,495,330)	108,892,162
Balance (in shares) at Mar. 31, 2019	43,576,081
Increase (Decrease) in Stockholders' Equity
Restricted stock grants	$ 26	(26)
Restricted stock grants (in shares)	257,000
Forfeiture of restricted stock grants	$ (3)	3
Forfeiture of restricted stock grants (in shares)	(31,971)
Stock-based compensation expense		8,311,729			8,311,729
Employee Stock Purchase Plan compensation expense		45,500			45,500
Issuance of common stock in connection with the ESPP		26,204			26,204
Issuance of common stock in connection with the ESPP (in shares)	2,348
Issuance of common stock in connection with the exercise of stock options	$ 7	277,658			277,665
Issuance of common stock in connection with the exercise of stock options (in shares)	72,221
Net loss				(16,841,422)	(16,841,422)
Other comprehensive income, net of tax			79,649		79,649
Balance at Jun. 30, 2019	$ 4,388	$ 434,071,363	$ 52,488	$ (333,336,752)	$ 100,791,487
Balance (in shares) at Jun. 30, 2019	43,875,679

Statements of Cash Flows

Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities
Net loss	$ (44,248,688)	$ (37,345,456)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	58,179	24,064
Stock-based compensation expense	15,517,821	5,612,068
Stock award - in-licensing	500,009
Employee Stock Purchase Plan compensation expense	70,353	25,350
Amortization of premium paid on marketable securities	(431,097)	(6,440)
Net gain loss on sale of marketable securities	4,324	3,897
Changes in operating assets and liabilities:
Accounts receivable	(15,093,121)
Inventories	(3,655,017)
Prepaid expenses and other current assets	(643,440)	(1,752,915)
Right-of-use asset, net	(1,469,714)
Accounts payable and accrued expenses	4,595,896	(1,563,431)
Right-of-use liability - current portion	1,042,526
Right-of-use liability	550,496
Other liabilities	(122,815)	(48,412)
Net cash used in operating activities	(43,324,288)	(35,051,275)
Cash flows from investing activities
Purchase of fixed assets	(74,495)
Purchase of marketable securities	(90,047,109)	(54,273,982)
Sale and maturities of marketable securities	54,326,954	35,467,670
Net cash used in investing activities	(35,794,650)	(18,806,312)
Cash flows from financing activities
Proceeds from issuance of common stock from follow-on public offerings, net	86,218,630	63,968,817
Proceeds from issuance of common stock from ESPP	128,770	117,219
Proceeds from exercise of stock options	293,490	1,533,323
Proceeds from exercise of warrants		352,530
Net cash provided by financing activities	86,640,890	65,971,889
Net increase in cash and cash equivalents	7,521,952	12,114,302
Cash and cash equivalents at beginning of period	9,443,667	4,795,098
Cash and cash equivalents at end of period	$ 16,965,619	$ 16,909,400

Organization and Basis of Prese

Organization and Basis of Presentation	6 Months Ended
	Jun. 30, 2019
Organization and Basis of Presentation
Organization and Basis of Presentation	1. Organization Stemline Therapeutics, Inc. (the “Company”) is a commercial-stage biopharmaceutical company focused on discovering, acquiring, developing and commercializing novel oncology therapeutics. The Company’s activities to date have primarily consisted of advancing ELZONRIS® (tagraxofusp-erzs; SL-401) through the clinical and regulatory process, launching and commercializing ELZONRIS, including building out a sales, marketing, and reimbursement infrastructure, developing and implementing its global regulatory and commercial strategies, developing its clinical and preclinical stage programs, including evaluating ELZONRIS in additional indications and other product candidates in various indications, expanding and strengthening its intellectual property portfolio, identifying and acquiring additional product and technology rights, investor relations efforts, and raising capital. The Company was incorporated in Delaware on August 8, 2003 and has its principal office in New York, New York. The Company has incurred losses from operations since inception of $345.0 million. Since its inception, most of its resources have been dedicated to drug discovery and acquisition, intellectual property, manufacturing, preclinical and clinical development of product candidates, regulatory strategy and implementation, and commercialization of ELZONRIS, an FDA-approved product. In particular, the Company has expended and will continue to expend, substantial resources for the foreseeable future commercializing its approved product in the U.S. and potentially abroad, should it be approved outside the U.S., developing its approved product for potential additional indications, developing its additional clinical stage product candidates, developing its preclinical stage product candidates, and continuing its asset acquisition efforts. These expenditures include costs associated with general and administrative, facilities, research and development, acquiring new technologies, manufacturing product and product candidates, conducting clinical trials and preclinical experiments, seeking regulatory input, including approvals, as well as commercializing any products approved for sale, including its approved product, ELZONRIS, in blastic plasmacytoid dendritic cell neoplasm (“BPDCN”). The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales from its approved product and/or from the potential approval of its currently approved product in additional indications, and/or in additional territories, or its other product candidates. The Company expects its research and development expenses to increase in connection with its ongoing and planned clinical trials and related manufacturing efforts, as well as for expenses related to the U.S. commercial launch of ELZONRIS and pursuit of potential regulatory approval and commercialization in additional ex-U.S. territories. The Company also anticipates that its selling, general and administrative expenses will be higher in future periods due to commercialization and ongoing optimization and build out of its commercial infrastructure and regulatory compliance systems to support the continued commercialization of ELZONRIS in the U.S. and potentially additional ex-U.S. territories. As a result, the Company expects to continue to incur operating losses for the foreseeable future. If adequate funds are not available to the Company on a timely basis, or at all, the Company may be required to delay or terminate commercialization, clinical trials or other development activities for its product and product candidates, for one or more indications or territories, or delay or terminate its establishment of sales and marketing capabilities, or other activities, that may be necessary to commercialize its products and product candidates. Basis of Presentation The accompanying unaudited financial statements have been prepared in accordance with the United States generally accepted accounting principles (“GAAP”) and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all information and footnotes required by GAAP for complete financial statements. In the opinion of management, the accompanying financial statements include all adjustments (including normal recurring adjustments) considered necessary for fair presentation of the Company’s financial position, results of operations and cash flows for the periods presented. Operating results for the current interim period are not necessarily indicative of the results that may be expected for the fiscal year ending December 31, 2019, or any future periods. This Form 10-Q should be read in conjunction with the audited financial statements and accompanying notes in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The Company believes that its existing cash, cash equivalents, and investments will be sufficient to cover its cash flow requirements for at least the next twelve months from the issuance date of these financial statements. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported financial position at the date of the financial statements and the reported results of operations during the reporting period. Such estimates and assumptions affect the reported amounts of assets, liabilities, income and expenses and disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Actual results could differ from those estimates.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2019
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note 2 of the Notes to the Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. During the six months ended June 30, 2019, the changes to the significant accounting policies mainly relate to the commercialization of ELZONRIS, which includes product net revenue, accounts receivable, and inventory. Revenue Recognition Effective January 1, 2018, the Company adopted Accounting Standards Codification (“ASC”) 606. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements, and financial instruments. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five step assessment: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception and once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract, determines which goods and services are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. The Company determined that the delivery of its product to its customer constitutes a single performance obligation as there are no other promises to deliver goods or services. Shipping and handling are considered to be fulfillment activities and are not considered separate performance obligations. The Company has assessed the existence of a significant financing component in the agreement with its customer. The payment terms with its customer do not exceed one year and therefore no amount of consideration has been allocated as a financing component. Taxes collected related to product sales are remitted to governmental authorities and are excluded from revenue. Product Revenue, Net The Company has obtained marketing approval from the U.S. Food and Drug Administration, (“FDA”) to sell ELZONRIS in the United States market. The Company sells ELZONRIS to its customer through its title distribution channel. The customer subsequently resells ELZONRIS to a limited number of specialty distributors who, in turn, distribute ELZONRIS to specialty hospitals. The Company recognizes revenue on sales of ELZONRIS when its customer obtains control of the product, which occurs at a point in time, typically upon delivery. Product revenues are recorded at the product’s wholesale acquisition costs, net of applicable reserves for variable consideration. Components of variable consideration include government contracts, product returns, commercial co-payment assistance program transactions, and distribution service fees. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are classified as a current liability. Overall, these reserves reflect our best estimates of the amount of consideration against product revenue that has been recognized. The amount of variable consideration which is included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under contracts will not occur in a future period. The Company’s analyses contemplate the application of the constraint in accordance with ASC 606. For the six months ended June 30, 2019, the Company determined a material reversal of revenue would not likely occur in a future period for the estimates detailed below and, therefore, the transaction price was not reduced further. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Government Contracts The Company have entered into contracts (i) to participate in the Medicaid Drug Rebate Program and the Medicare Part D program, and (ii) to sell to the U.S. Department of Veterans Affairs, 340b entities and other government agencies (“Government Payors”) so that ELZONRIS will be eligible for purchase by, in partial or full reimbursement from, such Government Payors. These reserves are recorded in the same period the revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included in accrued expenses and other current liabilities. For Medicare Part D, the Company estimates the number of patients in the prescription drug coverage gap for whom it will owe an additional discount under the Medicare Part D program. The Company estimates the rebates that it will provide to Government Payors for those programs that require rebates. These rebate estimates are based upon (i) the government-mandated discounts applicable to government-funded programs, (ii) information obtained from its customers and (iii) information obtained from other third parties regarding the payor mix for ELZONRIS. The liability for these rebates consists of estimates of claims for the current year and estimated future claims that will be made for product shipments that have been recognized as revenue but remain in the distribution channel inventories at the end of each reporting period. Product Returns Consistent with industry practice, the Company offers a limited right of return for product that has been purchased. To estimate sales with a right of return, the Company will assess, on a quarterly basis, the number of vials that are held in inventory throughout the distribution channel. Amounts for estimated product returns are established in the same period that the related gross revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses and other current liabilities. Commercial Co-payment Assistance Program The Company offers a co-payment assistance program where permitted by law and which is intended to provide financial assistance to qualified commercially-insured patients who are required to pay prescription drug copayments based on the terms of their prescription drug insurance plans. The calculation of the accrual for co-payment assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with product that has been recognized as revenue but remains in the distribution channel at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses and other current liabilities. Distribution Fees Distribution fees include fees paid to the Company’s distributors for the distribution of ELZONRIS based on contractual rates. In addition, the Company compensates for data and other administrative activities. Therefore, estimates for these costs are recorded as a reduction of revenue, based on contractual terms. Accounts Receivable, Net Accounts receivable, net primarily relates to amounts due from the Company’s customer, net of applicable revenue reserves. The Company analyzes accounts that are past due for collectability and provides an allowance for receivables when collection becomes doubtful. No reserve has been recorded relating to an allowance for doubtful accounts at June 30, 2019. Inventory The Company capitalizes inventory costs associated with the manufacturing of ELZONRIS after regulatory approval or when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized. Otherwise, such costs are expensed as research and development. The majority of manufacturing costs for ELZONRIS units recognized as revenue during the six months ended June 30, 2019 were expensed to research and development prior to FDA approval on December 21, 2018. The Company values its inventories at the lower of cost or estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period, and it writes down any excess and obsolete inventories to their estimated realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded within cost of product revenues. The determination of whether inventory costs will be realizable requires estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required which would be recorded as a cost of product sales in the statement of operations and comprehensive loss. Recently Issued Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”), issued a comprehensive new revenue recognition Accounting Standards Update (“ASU”) 2014-09, Revenue From Contracts With Customers (Topic 606) . ASU 2014-09 provides guidance to clarify the principles for recognizing revenue. This guidance includes the required steps to achieve the core principle that an entity should recognize income to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance is effective for fiscal years and interim periods beginning after December 15, 2017. Early adoption is permitted for fiscal years and interim periods beginning after December 15, 2016. The Company adopted this guidance on January 1, 2018, using the full retrospective method. Any future contracts with customers will be accounted for under the new guidance effective January 1, 2018. As noted below in Note 14 to the Company's Financial Statements, the Company has received grant income from the Leukemia and Lymphoma Society (“LLS”) to fund the Company's development program related to the Company's preclinical and clinical product development activities. The Company has determined that LLS is not a customer as defined by Topic 606. The Company recognizes grant income when there is reasonable assurance of compliance with the conditions of the grant and reasonable assurance that the grant income will be received based on the Company's best estimates of work performed and qualifying costs incurred. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC 840, Leases . The amendments in this update will increase the transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. Under ASU 2016-02, a lessee will recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. The recognition, measurement, and presentation of expenses and cash flows arising from a lease by a lessee have not significantly changed from current GAAP. ASU 2016-02 retains a distinction between finance leases and operating leases. The classification criteria for distinguishing between finance leases and operating leases will be substantially similar to the classification criteria for distinguishing between capital leases and operating leases under prior GAAP. Under the standard, disclosures are required to meet the objective of enabling users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The guidance permits a practical expedient with regards to initial adoption, allowing adopters the option to apply the new leases standard prospectively at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Under this expedient, comparative periods presented in the financial statements in which the new lease standard is adopted will continue to be presented in accordance with prior GAAP. The Company adopted this standard on January 1, 2019 using the prospective application method practical expedient. The adoption of this standard had an impact on our balance sheet, recognizing a right-of-use asset and lease liability of approximately $2 million. Refer to Note 8 for disclosure requirements related to the adoption of this standard. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables. In November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments - Credit Losses . ASU 2018-19 will affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposures, reinsurance receivables, and any other financial assets not excluded from the scope of this amendment that represent the contractual right to receive cash. ASU 2016-13 and ASU 2018-19 are effective for public entities for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact of adopting ASU 2016-13 on the Company’s financial statements. On June 20, 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting , which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. Entities should apply the requirements of Topic 718 to nonemployee awards except for specific guidance on inputs to an option pricing model and the period of time equity awards vest and the pattern of cost recognition over that period. ASU No. 2018-07 is effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted and the Company adopted ASU No. 2018-07 on April 1, 2018. The net impact relating to the early adoption was a $0.2 million decrease to accumulated deficit for the impact prior to April 1, 2018. In addition, the Company has elected to account for forfeitures of nonemployee awards as they occur. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement , which adds disclosure requirements to Topic 820 for the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. This ASU is effective for interim and annual reporting periods beginning after December 15, 2019. The adoption of ASU 2018-13 is not expected to have an impact on the Company's financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements. Under the amendments, an analysis of changes in each caption of stockholders' equity presented in the balance sheets must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. As such, the Company adopted these SEC amendments on November 5, 2018 and will present the analysis of changes in stockholders’ equity in its interim financial statements in its June 30, 2019 Form 10-Q. The Company does not anticipate that the adoption of these SEC amendments will have a material effect on the Company’s financial statements. In November 2018, ASU 2018-18 was issued to provide clarity on when transactions between entities in a collaborative arrangement should be accounted for under the new revenue standard, ASC 606. In determining whether transactions in collaborative arrangements should be accounted under the revenue standard, the update specifies that entities shall apply unit of account guidance to identify distinct goods or services and whether such goods and services are separately identifiable from other promises in the contract. ASU 2018-18 also precludes entities from presenting transactions with a collaborative partner which are not in scope of the new revenue standard together with revenue from contracts with customers. The accounting update is effective January 1, 2020 and early adoption is permitted. The adoption of ASU 2018-18 is not expected to have an impact on the Company’s financial statements. In December 2018, the FASB issued ASU 2018-20, Leases (Topic 842): Narrow-Scope Improvements for Lessors , which addressed implementation questions arising from stakeholders in regard to ASU 2016-02, Leases . Specifically addressed in this update were issues related to 1) sales taxes and other similar taxes collected from lessees, 2) certain lessor costs, and 3) recognition of variable payments for contracts with lease and nonlease components. The amendments in this ASU are effective in the same time-frame as ASU 2016-02, as discussed above. The Company incorporated this ASU into its assessment and adoption of ASU 2016-02.

Liquidity and Capital Resources

Liquidity and Capital Resources	6 Months Ended
	Jun. 30, 2019
Liquidity and Capital Resources
Liquidity and Capital Resources	3. Liquidity and Capital Resources As of June 30, 2019, the Company has approximately $103.9 million in cash, cash equivalents, and investment securities. The Company primarily invests in highly liquid cash equivalents, investments in U.S. Treasury and Agency securities and related money market funds and FDIC-insured bank certificates of deposit, with the balance in commercial bank operating accounts.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	6 Months Ended
	Jun. 30, 2019
Prepaid Expenses and Other Current Assets
Prepaid Expenses and Other Current Assets	4. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consist of the following at June 30, 2019 and December 31, 2018: June 30, December 31, 2019 2018 Prepaid third party vendor costs $ 1,714,355 $ 1,851,553 Deposits 492,794 189,000 Prepaid insurance 612,768 69,021 Other receivable 776,519 843,422 Total $ 3,596,436 $ 2,952,996

Property and Equipment, Net

Property and Equipment, Net	6 Months Ended
	Jun. 30, 2019
Property and Equipment, Net
Property and Equipment, Net	5. Property and Equipment, Net Property and equipment, net, consist of the following at June 30, 2019 and December 31, 2018: June 30, December 31, 2019 2018 Office furniture and fixtures $ 519,675 $ 519,675 Manufacturing equipment 181,753 107,258 Leasehold improvements 82,694 82,694 Capital lease equipment 29,529 29,529 Computer equipment 18,612 18,612 Property and equipment 832,263 757,768 Less accumulated depreciation and amortization (593,534) (535,355) Property and equipment, net $ 238,729 $ 222,413 Depreciation expense was $58,179 and $24,064 for the six-month periods ended June 30, 2019 and 2018, respectively.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2019
Fair Value Measurements
Fair Value Measurements	6. Fair Value Measurements 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 at the measurement date. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: Level 1 — Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 — Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly. Level 3 — Inputs that are unobservable for the asset or liability. The following fair value hierarchy table presents information about each major category of the Company’s financial assets and liability measured at fair value on a recurring basis as of June 30, 2019 and December 31, 2018: June 30, 2019 Quoted Prices in Active Significant Markets for Other Significant Balance Identical Observable Unobservable at Assets Inputs Inputs June 30, (Level 1) (Level 2) (Level 3) 2019 Assets: Fixed-income treasury portfolio $ 86,918,164 $ — $ — $ 86,918,164 Certificate of Deposits — — — — Cash and cash equivalents 16,965,619 — — 16,965,619 Total assets at fair value $ 103,883,783 $ — $ — $ 103,883,783 December 31, 2018 Quoted Prices in Active Significant Markets for Other Significant Balance Identical Observable Unobservable at Assets Inputs Inputs December 31, (Level 1) (Level 2) (Level 3) 2018 Assets: Fixed-income treasury portfolio $ 30,637,998 $ — $ — $ 30,637,998 Certificate of Deposits — 20,024,191 — 20,024,191 Cash and cash equivalents 9,443,667 — — 9,443,667 Total assets at fair value $ 40,081,665 $ 20,024,191 $ — $ 60,105,856 The following is a summary of cash equivalents and available-for-sale investments held by the Company at June 30, 2019 and December 31, 2018: June 30, 2019 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains* Losses* Value Cash: Cash from operating accounts $ 10,882,887 $ — $ — $ 10,882,887 Cash equivalents: Money market funds 6,082,732 — — 6,082,732 Total cash and cash equivalents $ 16,965,619 $ — $ — $ 16,965,619 Short-term investments: Fixed-income treasury portfolio: Fannie Mae 3,995,281 3,849 — 3,999,130 Federal farm credit bank 2,424,843 5,686 — 2,430,529 Freddie Mac 2,254,081 820 (1,420) 2,253,481 U.S. Treasury Securities 78,137,187 100,276 (2,439) 78,235,024 Total short-term investments 86,811,392 110,631 (3,859) 86,918,164 Total $ 103,777,011 $ 110,631 $ (3,859) $ 103,883,783 December 31, 2018 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains* Losses* Value Cash: Cash from operating accounts $ 2,482,621 $ — $ — $ 2,482,621 Cash equivalents: Money market funds 6,961,046 — — 6,961,046 Total cash and cash equivalents $ 9,443,667 $ — $ — $ 9,443,667 Short-term investments: Fixed-income treasury portfolio: Fannie Mae 2,013,336 — (1,146) 2,012,190 Federal home loan bank 6,020,492 — (10,646) 6,009,846 Freddie Mac 2,512,252 — (8,530) 2,503,722 U.S. Treasury Securities 20,123,026 767 (11,553) 20,112,240 Certificate of Deposits 20,024,346 — (155) 20,024,191 Total short-term investments 50,693,452 767 (32,030) 50,662,189 Total $ 60,137,119 $ 767 $ (32,030) $ 60,105,856 *The gross unrealized gains and losses captured in this footnote is before tax. At June 30, 2019 and December 31, 2018, the remaining contractual maturities of available-for-sale investments classified as current on the balance sheet were less than 12 months. There were no available-for-sale securities in a continuous unrealized loss position for greater than twelve months at June 30, 2019 and December 31, 2018. The Company has the ability to hold such securities with an unrealized loss until its forecasted recovery. The Company determined that there was no material change in the credit risk of the above investments. As a result, the Company determined it did not hold any investments with an other-than-temporary impairment as of June 30, 2019. Fair Value of Financial Instruments The Company’s financial instruments consist principally of cash and cash equivalents, investments, other current assets, accounts payable and accrued expenses. Cash and cash equivalents, and investments are carried at fair value (see above). Financial instruments including other current assets, accounts payable and accrued expenses are carried at cost, which approximate fair value given their short-term nature.

Inventory

Inventory	6 Months Ended
	Jun. 30, 2019
Inventory
Inventory	7. Inventory Inventory consists of the following: June 30, 2019 Raw materials $ 39,820 Work-in-process 3,297,314 Finished goods 317,883 Total Inventory $ 3,655,017 Inventory is related to our approved product, ELZONRIS. There were no write downs for excess and obsolete inventory during the six months ended June 30, 2019.

Leases

Leases	6 Months Ended
	Jun. 30, 2019
Leases
Leases	8. Leases The Company has leases for office facilities as well as for certain equipment. The operating lease portfolio is related to two office spaces and the financing lease relate to office equipment that was acquired in prior year. As of June 30, 2019, the Company has not entered into any new lease arrangements classified as a finance lease. Operating leases are included in operating lease right-of-use assets, current operating lease liabilities and operating lease liabilities on the Company’s balance sheet. The Company has elected the package of practical expedients which applies to leases that commenced before the adoption date. By electing the package of practical expedients, the Company did not need to reassess the following; whether any existing contracts are or contain leases, the lease classification for any existing leases and initial direct costs for any existing leases. Right-of-use asset and operating lease liabilities are recognized based on the present value of future minimum lease payments over the lease term at commencement date. When the implicit rate of the lease is not provided or cannot be determined, the Company used the incremental borrowing rate based on the information available at the commencement date to determine the present value of future payments. Lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise those options. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. Operating lease right-of-use asset is presented within right-of-use asset, net. The current portion of operating lease liabilities are presented within right-of-use liability - current portion and the non-current portion of operating lease liabilities are presented within right-of-use liability on the Balance Sheet. Finance lease assets are included in Property, plant and equipment - net, and the finance lease obligations are included in Other current liabilities debt, and in Other liabilities on the Balance Sheet. Components of lease expense and other information as follows: Six Months Ended June 30, 2019 Lease Expense Operating Lease Cost $ 529,385 Financing Lease Cost: Amortization of right-of-use assets 4,920 Interest on lease liability 554 Total financing lease cost 5,474 Total Lease Cost $ 534,859 June 30, Balance sheet information related to leases was as follows: 2019 Operating Leases Operating right-of-use asset, net $ 1,469,714 Operating right-of-use liability - current portion 1,042,526 Operating right-of-use liability 550,496 Total operating lease liabilities $ 1,593,022 Financing Leases Property, plant and equipment $ 29,529 Accumulated depreciation (10,663) Property, plant and equipment - net $ 18,866 Other current liabilities 9,876 Other liabilities 9,496 Total Financing lease liabilities $ 19,372 Weighted Average Remaining Lease Term - Operating Leases years Weighted Average Remaining Lease Term - Financing Leases years Weighted Average Discount Rate - Operating Leases 7.32 % Weighted Average Discount Rate - Financing Leases 5 % Future minimum lease payments under non-cancellable leases as of June 30, 2019 were as follows: Operating Financing Leases Leases 2019 $ 558,900 $ 5,310 2020 1,117,800 10,620 2021 — 4,425 Total future minimum lease payments 1,676,700 20,355 Less imputed interest (83,678) (983) Total $ 1,593,022 $ 19,372 Supplemental cash flow information related to leases was as follows: June 30, Cash paid for amounts included in the measurement of lease liabilities: 2019 Operating cash flows from operating leases $ 558,900 Operating cash flows from finance leases 554 Financing cash flows from finance leases 4,756

Accounts Payable and Accrued Ex

Accounts Payable and Accrued Expenses	6 Months Ended
	Jun. 30, 2019
Accounts Payable and Accrued Expenses
Accounts Payable and Accrued Expenses	9. Accounts Payable and Accrued Expenses Accounts payable and accrued expenses consist of the following at June 30, 2019 and December 31, 2018: June 30, December 31, 2019 2018 Accrued research and development costs $ 12,137,333 $ 8,790,920 Accrued compensation 4,037,792 5,515,002 Accrued legal 1,382,760 687,042 Accrued commercial costs 5,401,483 4,614,507 Accrued general and administrative costs 1,408,942 1,545,591 Accrued sales deduction and allowance 1,109,480 — Accrued royalty 271,168 — Total accounts payable and accrued expenses $ 25,748,958 $ 21,153,062

Common Stock

Common Stock	6 Months Ended
	Jun. 30, 2019
Common Stock
Common Stock	10. Common Stock On January 18, 2019, the Company completed a follow-on public offering, selling 8,888,889 shares at an offering price of $9 per share. Additionally, the underwriters exercised in full their over-allotment option to purchase an additional 1,333,333 shares at an offering price of $9 per share. Aggregate gross proceeds from the follow-on public offering, including the exercise of the over-allotment option, were $92 million, and net proceeds received after underwriting fees and offering expenses were approximately $86.2 million. The Company was authorized to issue 83,750,000 shares of common stock at June 30, 2019 and 53,750,000 shares of common stock at December 31, 2018. Dividends on common stock will be paid when, and if, declared by the board of directors. Each holder of common stock is entitled to vote on all matters and is entitled to one vote for each share held. The Company will, at all times, reserve and keep available, out of its authorized but unissued shares of common stock, sufficient shares to affect the conversion of shares from the exercise of stock options.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	6 Months Ended
	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)	11. Accumulated Other Comprehensive Income (Loss) The changes in accumulated balances for each component of other comprehensive loss are as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Balance at beginning of period $ (27,161) $ (150,377) $ (56,559) $ (145,958) Other comprehensive income before reclassification 79,649 27,404 104,723 19,088 Amounts reclassified from accumulated other comprehensive loss* — — 4,324 3,897 Total other comprehensive income 79,649 27,404 109,047 22,985 Balance at end of period $ 52,488 $ (122,973) $ 52,488 $ (122,973) *Amounts reclassified affect other income in the Statements of Operations.

Product revenue reserves and al

Product revenue reserves and allowances	6 Months Ended
	Jun. 30, 2019
Product revenue reserves and allowances
Product revenue reserves and allowances	12. Product revenue reserves and allowances As of June 30, 2019, the Company’s sole source of product revenue has been from sales of ELZONRIS in the United States. The following table summarizes activity in each of the product revenue allowance and reserve categories for the three and six months ended June 30, 2019: Three Months Ended June 30, 2019 Commercial Co-payment Government Product Assistance Distribution Rebates Returns Programs Fees Total Beginning balance at March 31, 2019 $ 172,688 $ 202,769 $ 52,181 $ 142,672 $ 570,310 Provision related to sales in the current quarter 725,102 465,281 944 337,815 1,529,142 Adjustments related to prior period sale — — — — — Credits and payments made (416,394) (537,460) — (61,011) (1,014,865) Ending balance at June 30, 2019 $ 481,396 $ 130,590 $ 53,125 $ 419,476 $ 1,084,587 Six Months Ended June 30, 2019 Commercial Co-payment Government Product Assistance Distribution Rebates Returns Programs Fees Total Beginning balance at December 31, 2018 $ — $ — $ — $ — $ — Provision related to sales in the current year 897,790 668,050 53,125 480,487 2,099,452 Adjustments related to prior period sale — — — — — Credits and payments made (416,394) (537,460) — (61,011) (1,014,865) Ending balance at June 30, 2019 $ 481,396 $ 130,590 $ 53,125 $ 419,476 $ 1,084,587 Government rebates, product returns, commercial co-payment assistance programs, and distribution fees are recorded as a component of accrued expenses on the balance sheet.

Net Loss Per Common Share

Net Loss Per Common Share	6 Months Ended
	Jun. 30, 2019
Net Loss Per Common Share
Net Loss Per Common Share	13. Net Loss Per Common Share The Company accounts for and discloses net loss per share using the treasury stock method. Net loss per common share, or basic loss per share, is computed by dividing net loss by the weighted-average number of common shares outstanding. Since the Company is in a net loss for all periods presented, diluted net loss per share is not presented since the common stock equivalents would have an anti-dilutive effect on the per share calculation. The following table sets forth the computation of basic and diluted net loss per share for the periods indicated: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Basic and diluted net loss per common share calculation: Net loss $ (16,841,422) $ (18,928,703) $ (44,248,688) $ (37,345,456) Basic and diluted weighted-average common shares 40,108,267 28,567,982 38,836,664 27,851,707 Basic and diluted net loss per share $ (0.42) $ (0.66) $ (1.14) $ (1.34) The difference between basic and diluted weighted-average common shares generally results from the assumption that dilutive stock options outstanding were exercised and dilutive restricted stock has vested. For the six-month periods ended June 30, 2019 and 2018, the Company reported a loss from operations and therefore, all potentially dilutive stock options and restricted stock as of such date were excluded from the computation of diluted net loss per share as their effect would have been anti-dilutive. The total shares of stock options and restricted stock that could potentially dilute earnings per share in the future, but which were not included in the calculation of diluted net loss per share because their affect would have been anti-dilutive were as follows: Six Months Ended June 30, 2019 2018 Restricted stock 3,427,168 1,926,706 Options outstanding 3,446,591 3,144,768 Total 6,873,759 5,071,474

Grant Income

Grant Income	6 Months Ended
	Jun. 30, 2019
Grant Income
Grant Income	14. Grant Income In October 2013, the Company entered into a contract with the LLS. LLS is a national voluntary health organization that, among other activities, encourages and sponsors research relating to blood cancers to develop therapies to cure or mitigate these diseases. To further its mission, LLS provides research funding to entities that can demonstrate after LLS’s review process that their proposed research projects have scientific promise to advance LLS’s effort to find treatments and cures for blood cancers and their complications. LLS agreed to provide funding to the Company not to exceed $3.5 million to fund the Company’s development program related to the Company’s preclinical and clinical product development activities. Through June 30, 2019, the Company has received $3.5 million based on milestones achieved. The agreement terminates when there are no longer any payment obligations for either LLS or Stemline.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Taxes
Income Taxes	15. Income Taxes The Company recorded $22,194 income tax benefit related to intraperiod tax allocations for the six-month period ended June 30, 2019 and no income tax provisions or benefits were recorded for the six-month period ended June 30, 2018, due to the fact that the Company cannot benefit from its net operating losses or other deferred tax assets. The Company does not currently have the ability to carry back losses to previous years to recover taxes paid and future utilization of these losses is uncertain. The Company files income tax returns in the United States and in the State of New York. The Company currently has no ongoing audits. Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and their basis for income tax purposes and the tax effects of net operating loss and tax credit carryforwards. Valuation allowances reduce deferred tax assets to the amounts that are more likely than not to be realized. As of June 30, 2019, the Company has recorded additional deferred tax assets which are fully offset by a valuation allowance. Realization of the deferred tax assets is dependent on generating sufficient taxable income in the future. At present, the likelihood of the Company being able to fully utilize its deferred income tax benefits against future income is uncertain.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2019
Stock-Based Compensation
Stock-Based Compensation	16. Stock-Based Compensation The Company’s 2016 Stock Equity Incentive Plan (the “2016 Plan”) was adopted by the board of directors and approved by the stockholders in May 2016. The 2016 Plan authorizes the Company to grant up to 1,812,932 shares of common stock to eligible employees, directors, and non-employee consultants and advisors to the Company. Under the provisions of the 2016 Plan, no option will have a term in excess of 10 years. The Company’s stockholders approved an increase of 1,200,000 shares, an increase of 2,900,000 shares, and an increase of 2,500,000 shares authorized under the 2016 Plan during 2017, 2018, and 2019, respectively. As of June 30, 2019, there were 2,624,469 shares of common stock available for future grants under the 2016 Plan. Total compensation cost that has been charged against operations related to the above plans was approximately $15.5 million and $5.6 million for the six-month periods ended June 30, 2019 and 2018, respectively. The following table summarizes stock-based compensation related to the above plans by expense category for the three and six month periods ended June 30, 2019 and 2018, respectively: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Research and development $ 3,221,426 $ 1,216,018 $ 6,327,485 $ 2,186,643 Selling, general and administrative 5,090,303 2,189,623 9,190,336 3,425,425 Total $ 8,311,729 $ 3,405,641 $ 15,517,821 $ 5,612,068 The following table summarizes the stock-based compensation capitalized to inventory: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Stock-based compensation expense capitalized to inventory $ 181,551 $ — $ 237,108 $ — Stock Options The Company grants stock options to employees, directors and non-employee consultants, with exercise prices equal to the closing price of the underlying shares of the Company’s common stock on the date that the options are granted. Options granted have a term of 10 years from the grant date. Options granted to employees generally vest over a four-year period from date of grant or if vesting based on market condition, awards vest based on the derived service period which is the estimated period of time that would be required to satisfy the market condition. Options granted to directors’ vest in equal yearly installments over a three-year period from the date of grant. Options to directors may be granted on an annual basis and represent compensation for services performed on the Board of Directors. Compensation cost for stock options granted to employees and directors is charged against operations using the straight-line attribution method between the grant date for the option and each vesting date. The Company estimates the fair value of stock options on the grant date by applying the Black-Scholes option pricing valuation model. The application of this valuation model involves assumptions that are highly subjective, judgmental and sensitive in the determination of compensation cost. The weighted-average key assumptions used in determining the fair value of options granted for the three and six month periods ended June 30, 2019 and 2018, respectively are as follows: Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Weighted-average volatility 65.94 % 77.27 % 66.23 % 77.53 % Weighted-average risk-free interest rate 2.22 % 2.82 % 2.42 % 2.75 % Weighted-average expected term in years 6.26 6.26 6.26 6.26 Dividend yield — — — — The Company’s computation of stock-price volatility is based on the volatility rates of comparable publicly held companies over a period equal to the estimated useful life of the options granted by the Company. The Company’s computation of expected life was determined using the “simplified” method which is the midpoint between the vesting date and the end of the contractual term. The Company believes that it does not have sufficient reliable exercise data in order to justify the use of a method other than the “simplified” method of estimating the expected exercise term of employee stock option grants. The Company has paid no dividends to stockholders. The risk-free interest rate is based on the zero-coupon U.S. Treasury yield at the date of grant for a term equivalent to the expected term of the option. For the six-month period ended June 30, 2019, the Company issued 74,721 shares of the Company's common stock upon the exercise of outstanding stock options and received proceeds of approximately $0.3 million. As of June 30, 2019, there was approximately $5.9 million of unrecognized compensation cost related to unamortized stock option compensation which is expected to be recognized over a remaining weighted-average period of approximately 2.32 years. The following table summarizes the activity related to the Company’s stock options for the six months ended June 30, 2019: Weighted- Average Weighted- Remaining Aggregate Average Contractual Intrinsic Options Exercise Price Life Value Outstanding at December 31, 2018 3,514,018 $ 9.59 Options granted Options exercised Options forfeited Outstanding at June 30, 2019 $ $ Options exercisable at June 30, 2019 $ $ The aggregate intrinsic value in the previous table reflects the total pretax intrinsic value (the difference between the Company’s closing stock price on the last trading day of the quarter ended June 30, 2019 and the exercise price of the options, multiplied by the number of in-the-money stock options) that would have been received by the option holders had all option holders exercised their options on June 30, 2019. The intrinsic value of the Company’s stock options changes based on the closing price of the Company’s common stock. Restricted Stock Awards The Company grants restricted stock to its employees, directors, and non-employee consultants. Restricted stock is recorded as deferred compensation and charged against income on a straight-line basis over the vesting period, which ranges from immediate to four years in duration. If vesting of the award is based on a performance or market condition, awards vest based on the derived service period which is the estimated period of time that would be required to satisfy the performance or market condition. Restricted stock awards to directors vest in equal installments over a three-year period from the grant date. Compensation cost for restricted stock is based on the award’s grant date fair value, which is the closing market price of the Company’s common stock on the grant date, multiplied by the number of shares awarded. The following table summarizes the activity related to the Company’s restricted stock for the six months ended June 30, 2019: Weighted- Average Grant Date Fair Value Number of Shares Per Share Outstanding at December 31, 2018 2,794,455 $ 12.79 Shares granted 11.74 Shares vested 12.61 Shares forfeited 13.24 Outstanding at June 30, 2019 $ 12.33 For the six-month period ended June 30, 2019, the Company granted 1,623,471 shares of restricted stock at a weighted-average grant date fair value of $11.74 per share amounting to approximately $19.1 million in total aggregate fair value. As of June 30, 2019, 3,427,168 shares remained unvested and there was approximately $32.5 million of unrecognized compensation cost related to restricted stock which is expected to be recognized over a remaining weighted-average period of approximately 1.83 years. The total fair value of restricted stock vested during the six-month periods ended June 30, 2019 and 2018 was approximately $11.9 million and $4.1 million, respectively. Restricted Stock Units The Company grants restricted stock units (RSU) to its employees. RSU is recorded as deferred compensation and charged against income on a straight-line basis over the vesting period, usually four years in duration. Compensation cost for RSU is based on the grant date fair value, which is the closing market price of the Company’s common stock on the grant date, multiplied by the number of units awarded. The following table summarizes the activity related to the Company’s RSU for the six months ended June 30, 2019: Weighted- Average Grant Date Fair Value Number of Shares Per Unit Outstanding at December 31, 2018 — $ — Shares granted 14,000 13.29 Shares vested — — Shares forfeited — — Outstanding at June 30, 2019 14,000 $ 13.29 For the six-month period ended June 30, 2019, the Company granted 14,000 shares of RSU at a weighted-average grant date fair value of $13.29 per share amounting to approximately $0.2 million in total aggregate fair value. As of June 30, 2019, 14,000 shares remained unvested and there was approximately $0.2 million of unrecognized compensation cost related to restricted stock which is expected to be recognized over a remaining weighted-average period of approximately 3.95 years. The total fair value of RSU vested during the six-month periods ended June 30, 2019 was $0. Performance Share Awards On August 2018, the FDA accepted the Company's Biologics License Application, or BLA, for ELZONRIS for the treatment of BPDCN, in adults and in pediatric patients two years and older. As a result of the approval, the underlying performance condition associated with the performance share awards, or PSAs, were met. The Company recognized approximately $0.4 million and $37,514 of stock compensation expense related to the PSAs for six-month periods ended June 30, 2019 and 2018, respectively. In addition, ELZONRIS received FDA approval on December 21, 2018 for the treatment of patients with BPDCN. As a result of the approval, the underlying performance condition associated with the PSAs were met and the Company recognized approximately $5.1 million and $0 of stock compensation expense related to the PSAs for the six-month periods ended June 30, 2019 and 2018, respectively. For awards with performance conditions, such as obtaining regulatory approval on a developed product, capital raises, a change in control or a sale of the company, no expense is recognized, and no measurement date can occur, until the occurrence of the event is probable. Awards Granted to Non-Employee Consultants The Company grants stock options, restricted stock, and unrestricted stock to non-employee consultants. The Company measures the fair value of stock-based awards issued to non-employees and records expense over the requisite service period. Total compensation cost charged against operations related to stock-based awards granted to non-employee consultants was approximately $0.3 million and $1.1 million for the six-month periods ended June 30, 2019 and 2018, respectively. Employee Stock Purchase Plan In September 2015, the Company adopted its 2015 Employee Stock Purchase Plan (the “2015 ESPP”). The 2015 ESPP is qualified as an employee stock purchase plan under Section 423 of the Internal Revenue Code of 1986, as amended (the “IRC”). Under the 2015 ESPP, the Company will grant rights to purchase shares of common stock under the 2015 ESPP (“Rights”) at prices not less than 85% of the lesser of (i) the fair value of the shares on the date of grant of such Rights or (ii) the fair value of the shares on the date such Rights are exercised. Therefore, the 2015 ESPP is considered compensatory under FASB ASC 718 since, along with other factors, it includes a purchase discount of greater than 5%. The Company recorded approximately $70,353 and $25,350 of compensation expense for the six-month periods ended June 30, 2019 and 2018, respectively, related to participation in the 2015 ESPP.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies
Commitments and Contingencies	17. Commitments and Contingencies The Company has entered into research and development agreements with third parties for the development of oncology product candidates and technologies. According to these agreements, the Company typically funds the development of such assets and potentially makes development-based milestone payments, and royalty and sales-based milestone payments based on net sales should the product candidates be approved for marketing. The timing and the amounts of milestone and royalty payments in the future are not certain. The Company has also entered into license agreements, including ones with licenses to certain intellectual property rights, in the field of oncology and other indications. The Company is generally required to make upfront payments as well as other payments upon successful completion of preclinical, clinical, regulatory or sales milestones, should such milestones occur. In addition, these agreements generally would require the Company to pay royalties on sales of the products arising from these agreements, should a product candidate under the license agreement receive regulatory approval. These agreements generally permit the Company to terminate the agreement with no significant continuing obligation. Under the Company’s research and development and/or license agreements, if the Company were to achieve certain milestones, primarily late stage clinical trial events, marketing approval, and sales, the Company could be required to pay up to a total of $375.6 million in future periods. As of June 30, 2019, the Company has paid or accrued $7.9 million in payments pursuant to such agreements. If a product candidate under such agreements were to receive marketing approval, royalty payments, largely single digit, are payable on commercial sales of certain products. The Company has committed to make potential future milestone and royalty payments to third parties as part of its research and development and licensing agreements. Payments generally become due and payable only upon the achievement of certain developmental, regulatory and/or commercial milestones. Because the achievement of these milestones is neither guaranteed nor reasonably estimable, the Company has not recorded a liability on its balance sheet for any such contingencies. Contractual Agreements The Company has entered into contracts with a pharmaceutical drug substance manufacturer over the past six years totaling $33.6 million, with services to be rendered on some of these agreements through 2019. From inception through June 30, 2019, the Company has received and paid for services relating to these agreements in the amount of $28.6 million. In addition, the Company has a commercial supply agreement with a vendor in which the Company is required to manufacture at least one batch during 2019. The Company has agreements in place with contract research organizations, or CROs, in connection with its clinical programs. The Company’s total expenditures in the future would be approximately $1.6 million assuming the successful advancement of its programs. Agreement with the Leukemia and Lymphoma Society In October 2013, the Company entered into a contract with the LLS. LLS is a national voluntary health organization which, among other activities, encourages and sponsors research relating to blood cancers to develop therapies to cure or mitigate these diseases. To further its mission, LLS provides research funding to entities that can demonstrate, after LLS’s review process, that their proposed research projects have scientific promise to advance LLS’s effort to find treatments and cures for blood cancers and their complications. LLS agreed to provide funding to the Company, not to exceed $3.5 million, to contribute to the Company’s development program. From inception through June 30, 2019, the Company has received $3.5 million based on milestones achieved. For the six-month period ended June 30, 2019, the Company recorded expense of approximately $4.4 million relating to the achievement of a post-approval milestone. Contingencies On March 15, 2018, the United States District Court for the Southern District of New York granted a motion to dismiss in its entirety a consolidated shareholder action against the Company, its directors, certain of its officers, and the lead underwriter. This matter originated from lawsuits filed in February 2017. On March 12, 2019, Lead Plaintiffs filed a joint stipulation of settlement in support of their motion for preliminary approval of a settlement of the consolidated shareholder action with the United States District Court for the Southern District of New York, after the Plaintiffs voluntarily withdrew their appeal pursuant to Local Rule 42.1. On June 14, 2019, the United States District Court for the Southern District of New York entered an order granting preliminary approval of the settlement of the consolidated securities action and set a final approval hearing for September 23, 2019. On June 25, 2019, a shareholder derivative action was filed in the Supreme Court of the State of New York, New York County. The Company is named solely as a nominal defendant. The suit seeks damages and equitable relief related to the Company's directors' compensation in each year of 2013 through 2018. Given the early stages of this matter, at this time, it is not possible to estimate the amount of any loss, or whether there will be any loss at all.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2019
Summary of Significant Accounting Policies
Revenue Recognition	Revenue Recognition Effective January 1, 2018, the Company adopted Accounting Standards Codification (“ASC”) 606. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as leases, insurance, collaboration arrangements, and financial instruments. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five step assessment: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception and once the contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract, determines which goods and services are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. The Company determined that the delivery of its product to its customer constitutes a single performance obligation as there are no other promises to deliver goods or services. Shipping and handling are considered to be fulfillment activities and are not considered separate performance obligations. The Company has assessed the existence of a significant financing component in the agreement with its customer. The payment terms with its customer do not exceed one year and therefore no amount of consideration has been allocated as a financing component. Taxes collected related to product sales are remitted to governmental authorities and are excluded from revenue. Product Revenue, Net The Company has obtained marketing approval from the U.S. Food and Drug Administration, (“FDA”) to sell ELZONRIS in the United States market. The Company sells ELZONRIS to its customer through its title distribution channel. The customer subsequently resells ELZONRIS to a limited number of specialty distributors who, in turn, distribute ELZONRIS to specialty hospitals. The Company recognizes revenue on sales of ELZONRIS when its customer obtains control of the product, which occurs at a point in time, typically upon delivery. Product revenues are recorded at the product’s wholesale acquisition costs, net of applicable reserves for variable consideration. Components of variable consideration include government contracts, product returns, commercial co-payment assistance program transactions, and distribution service fees. These reserves, as detailed below, are based on the amounts earned, or to be claimed on the related sales, and are classified as a current liability. Overall, these reserves reflect our best estimates of the amount of consideration against product revenue that has been recognized. The amount of variable consideration which is included in the transaction price may be constrained and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized under contracts will not occur in a future period. The Company’s analyses contemplate the application of the constraint in accordance with ASC 606. For the six months ended June 30, 2019, the Company determined a material reversal of revenue would not likely occur in a future period for the estimates detailed below and, therefore, the transaction price was not reduced further. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Government Contracts The Company have entered into contracts (i) to participate in the Medicaid Drug Rebate Program and the Medicare Part D program, and (ii) to sell to the U.S. Department of Veterans Affairs, 340b entities and other government agencies (“Government Payors”) so that ELZONRIS will be eligible for purchase by, in partial or full reimbursement from, such Government Payors. These reserves are recorded in the same period the revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability, which is included in accrued expenses and other current liabilities. For Medicare Part D, the Company estimates the number of patients in the prescription drug coverage gap for whom it will owe an additional discount under the Medicare Part D program. The Company estimates the rebates that it will provide to Government Payors for those programs that require rebates. These rebate estimates are based upon (i) the government-mandated discounts applicable to government-funded programs, (ii) information obtained from its customers and (iii) information obtained from other third parties regarding the payor mix for ELZONRIS. The liability for these rebates consists of estimates of claims for the current year and estimated future claims that will be made for product shipments that have been recognized as revenue but remain in the distribution channel inventories at the end of each reporting period. Product Returns Consistent with industry practice, the Company offers a limited right of return for product that has been purchased. To estimate sales with a right of return, the Company will assess, on a quarterly basis, the number of vials that are held in inventory throughout the distribution channel. Amounts for estimated product returns are established in the same period that the related gross revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses and other current liabilities. Commercial Co-payment Assistance Program The Company offers a co-payment assistance program where permitted by law and which is intended to provide financial assistance to qualified commercially-insured patients who are required to pay prescription drug copayments based on the terms of their prescription drug insurance plans. The calculation of the accrual for co-payment assistance is based on an estimate of claims and the cost per claim that the Company expects to receive associated with product that has been recognized as revenue but remains in the distribution channel at the end of each reporting period. The adjustments are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a current liability which is included as a component of accrued expenses and other current liabilities. Distribution Fees Distribution fees include fees paid to the Company’s distributors for the distribution of ELZONRIS based on contractual rates. In addition, the Company compensates for data and other administrative activities. Therefore, estimates for these costs are recorded as a reduction of revenue, based on contractual terms.
Accounts Receivable, Net	Accounts Receivable, Net Accounts receivable, net primarily relates to amounts due from the Company’s customer, net of applicable revenue reserves. The Company analyzes accounts that are past due for collectability and provides an allowance for receivables when collection becomes doubtful. No reserve has been recorded relating to an allowance for doubtful accounts at June 30, 2019.
Inventory	Inventory The Company capitalizes inventory costs associated with the manufacturing of ELZONRIS after regulatory approval or when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized. Otherwise, such costs are expensed as research and development. The majority of manufacturing costs for ELZONRIS units recognized as revenue during the six months ended June 30, 2019 were expensed to research and development prior to FDA approval on December 21, 2018. The Company values its inventories at the lower of cost or estimated net realizable value. The Company determines the cost of its inventories, which includes amounts related to materials and manufacturing overhead, on a first-in, first-out basis. The Company performs an assessment of the recoverability of capitalized inventory during each reporting period, and it writes down any excess and obsolete inventories to their estimated realizable value in the period in which the impairment is first identified. Such impairment charges, should they occur, are recorded within cost of product revenues. The determination of whether inventory costs will be realizable requires estimates by management. If actual market conditions are less favorable than projected by management, additional write-downs of inventory may be required which would be recorded as a cost of product sales in the statement of operations and comprehensive loss.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”), issued a comprehensive new revenue recognition Accounting Standards Update (“ASU”) 2014-09, Revenue From Contracts With Customers (Topic 606) . ASU 2014-09 provides guidance to clarify the principles for recognizing revenue. This guidance includes the required steps to achieve the core principle that an entity should recognize income to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance is effective for fiscal years and interim periods beginning after December 15, 2017. Early adoption is permitted for fiscal years and interim periods beginning after December 15, 2016. The Company adopted this guidance on January 1, 2018, using the full retrospective method. Any future contracts with customers will be accounted for under the new guidance effective January 1, 2018. As noted below in Note 14 to the Company's Financial Statements, the Company has received grant income from the Leukemia and Lymphoma Society (“LLS”) to fund the Company's development program related to the Company's preclinical and clinical product development activities. The Company has determined that LLS is not a customer as defined by Topic 606. The Company recognizes grant income when there is reasonable assurance of compliance with the conditions of the grant and reasonable assurance that the grant income will be received based on the Company's best estimates of work performed and qualifying costs incurred. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which supersedes ASC 840, Leases . The amendments in this update will increase the transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. Under ASU 2016-02, a lessee will recognize in the statement of financial position a liability to make lease payments (the lease liability) and a right-of-use asset representing its right to use the underlying asset for the lease term. The recognition, measurement, and presentation of expenses and cash flows arising from a lease by a lessee have not significantly changed from current GAAP. ASU 2016-02 retains a distinction between finance leases and operating leases. The classification criteria for distinguishing between finance leases and operating leases will be substantially similar to the classification criteria for distinguishing between capital leases and operating leases under prior GAAP. Under the standard, disclosures are required to meet the objective of enabling users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The guidance permits a practical expedient with regards to initial adoption, allowing adopters the option to apply the new leases standard prospectively at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Under this expedient, comparative periods presented in the financial statements in which the new lease standard is adopted will continue to be presented in accordance with prior GAAP. The Company adopted this standard on January 1, 2019 using the prospective application method practical expedient. The adoption of this standard had an impact on our balance sheet, recognizing a right-of-use asset and lease liability of approximately $2 million. Refer to Note 8 for disclosure requirements related to the adoption of this standard. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses on certain types of financial instruments, including trade receivables. In November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments - Credit Losses . ASU 2018-19 will affect loans, debt securities, trade receivables, net investments in leases, off balance sheet credit exposures, reinsurance receivables, and any other financial assets not excluded from the scope of this amendment that represent the contractual right to receive cash. ASU 2016-13 and ASU 2018-19 are effective for public entities for fiscal years beginning after December 15, 2019, with early adoption permitted. The Company is currently evaluating the impact of adopting ASU 2016-13 on the Company’s financial statements. On June 20, 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting , which expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. Entities should apply the requirements of Topic 718 to nonemployee awards except for specific guidance on inputs to an option pricing model and the period of time equity awards vest and the pattern of cost recognition over that period. ASU No. 2018-07 is effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted and the Company adopted ASU No. 2018-07 on April 1, 2018. The net impact relating to the early adoption was a $0.2 million decrease to accumulated deficit for the impact prior to April 1, 2018. In addition, the Company has elected to account for forfeitures of nonemployee awards as they occur. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement , which adds disclosure requirements to Topic 820 for the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements. This ASU is effective for interim and annual reporting periods beginning after December 15, 2019. The adoption of ASU 2018-13 is not expected to have an impact on the Company's financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements. Under the amendments, an analysis of changes in each caption of stockholders' equity presented in the balance sheets must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. As such, the Company adopted these SEC amendments on November 5, 2018 and will present the analysis of changes in stockholders’ equity in its interim financial statements in its June 30, 2019 Form 10-Q. The Company does not anticipate that the adoption of these SEC amendments will have a material effect on the Company’s financial statements. In November 2018, ASU 2018-18 was issued to provide clarity on when transactions between entities in a collaborative arrangement should be accounted for under the new revenue standard, ASC 606. In determining whether transactions in collaborative arrangements should be accounted under the revenue standard, the update specifies that entities shall apply unit of account guidance to identify distinct goods or services and whether such goods and services are separately identifiable from other promises in the contract. ASU 2018-18 also precludes entities from presenting transactions with a collaborative partner which are not in scope of the new revenue standard together with revenue from contracts with customers. The accounting update is effective January 1, 2020 and early adoption is permitted. The adoption of ASU 2018-18 is not expected to have an impact on the Company’s financial statements. In December 2018, the FASB issued ASU 2018-20, Leases (Topic 842): Narrow-Scope Improvements for Lessors , which addressed implementation questions arising from stakeholders in regard to ASU 2016-02, Leases . Specifically addressed in this update were issues related to 1) sales taxes and other similar taxes collected from lessees, 2) certain lessor costs, and 3) recognition of variable payments for contracts with lease and nonlease components. The amendments in this ASU are effective in the same time-frame as ASU 2016-02, as discussed above. The Company incorporated this ASU into its assessment and adoption of ASU 2016-02.

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	6 Months Ended
	Jun. 30, 2019
Prepaid Expenses and Other Current Assets
Schedule of prepaid expenses and other current assets	June 30, December 31, 2019 2018 Prepaid third party vendor costs $ 1,714,355 $ 1,851,553 Deposits 492,794 189,000 Prepaid insurance 612,768 69,021 Other receivable 776,519 843,422 Total $ 3,596,436 $ 2,952,996

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	6 Months Ended
	Jun. 30, 2019
Property and Equipment, Net
Schedule of property and equipment, net	June 30, December 31, 2019 2018 Office furniture and fixtures $ 519,675 $ 519,675 Manufacturing equipment 181,753 107,258 Leasehold improvements 82,694 82,694 Capital lease equipment 29,529 29,529 Computer equipment 18,612 18,612 Property and equipment 832,263 757,768 Less accumulated depreciation and amortization (593,534) (535,355) Property and equipment, net $ 238,729 $ 222,413

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Measurements
Schedule of the Company's financial assets and liability measured at fair value on a recurring basis	June 30, 2019 Quoted Prices in Active Significant Markets for Other Significant Balance Identical Observable Unobservable at Assets Inputs Inputs June 30, (Level 1) (Level 2) (Level 3) 2019 Assets: Fixed-income treasury portfolio $ 86,918,164 $ — $ — $ 86,918,164 Certificate of Deposits — — — — Cash and cash equivalents 16,965,619 — — 16,965,619 Total assets at fair value $ 103,883,783 $ — $ — $ 103,883,783 December 31, 2018 Quoted Prices in Active Significant Markets for Other Significant Balance Identical Observable Unobservable at Assets Inputs Inputs December 31, (Level 1) (Level 2) (Level 3) 2018 Assets: Fixed-income treasury portfolio $ 30,637,998 $ — $ — $ 30,637,998 Certificate of Deposits — 20,024,191 — 20,024,191 Cash and cash equivalents 9,443,667 — — 9,443,667 Total assets at fair value $ 40,081,665 $ 20,024,191 $ — $ 60,105,856
Summary of cash equivalents and available-for-sale investments held by the Company	June 30, 2019 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains* Losses* Value Cash: Cash from operating accounts $ 10,882,887 $ — $ — $ 10,882,887 Cash equivalents: Money market funds 6,082,732 — — 6,082,732 Total cash and cash equivalents $ 16,965,619 $ — $ — $ 16,965,619 Short-term investments: Fixed-income treasury portfolio: Fannie Mae 3,995,281 3,849 — 3,999,130 Federal farm credit bank 2,424,843 5,686 — 2,430,529 Freddie Mac 2,254,081 820 (1,420) 2,253,481 U.S. Treasury Securities 78,137,187 100,276 (2,439) 78,235,024 Total short-term investments 86,811,392 110,631 (3,859) 86,918,164 Total $ 103,777,011 $ 110,631 $ (3,859) $ 103,883,783 December 31, 2018 Gross Gross Estimated Amortized Unrealized Unrealized Fair Cost Gains* Losses* Value Cash: Cash from operating accounts $ 2,482,621 $ — $ — $ 2,482,621 Cash equivalents: Money market funds 6,961,046 — — 6,961,046 Total cash and cash equivalents $ 9,443,667 $ — $ — $ 9,443,667 Short-term investments: Fixed-income treasury portfolio: Fannie Mae 2,013,336 — (1,146) 2,012,190 Federal home loan bank 6,020,492 — (10,646) 6,009,846 Freddie Mac 2,512,252 — (8,530) 2,503,722 U.S. Treasury Securities 20,123,026 767 (11,553) 20,112,240 Certificate of Deposits 20,024,346 — (155) 20,024,191 Total short-term investments 50,693,452 767 (32,030) 50,662,189 Total $ 60,137,119 $ 767 $ (32,030) $ 60,105,856 *The gross unrealized gains and losses captured in this footnote is before tax.

Inventory (Tables)

Inventory (Tables)	6 Months Ended
	Jun. 30, 2019
Inventory
Schedule of inventories	June 30, 2019 Raw materials $ 39,820 Work-in-process 3,297,314 Finished goods 317,883 Total Inventory $ 3,655,017

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2019
Leases
Schedule of component of lease expense and other information	Six Months Ended June 30, 2019 Lease Expense Operating Lease Cost $ 529,385 Financing Lease Cost: Amortization of right-of-use assets 4,920 Interest on lease liability 554 Total financing lease cost 5,474 Total Lease Cost $ 534,859 June 30, Balance sheet information related to leases was as follows: 2019 Operating Leases Operating right-of-use asset, net $ 1,469,714 Operating right-of-use liability - current portion 1,042,526 Operating right-of-use liability 550,496 Total operating lease liabilities $ 1,593,022 Financing Leases Property, plant and equipment $ 29,529 Accumulated depreciation (10,663) Property, plant and equipment - net $ 18,866 Other current liabilities 9,876 Other liabilities 9,496 Total Financing lease liabilities $ 19,372 Weighted Average Remaining Lease Term - Operating Leases years Weighted Average Remaining Lease Term - Financing Leases years Weighted Average Discount Rate - Operating Leases 7.32 % Weighted Average Discount Rate - Financing Leases 5 %
Schedule of future minimum lease payments	Future minimum lease payments under non-cancellable leases as of June 30, 2019 were as follows: Operating Financing Leases Leases 2019 $ 558,900 $ 5,310 2020 1,117,800 10,620 2021 — 4,425 Total future minimum lease payments 1,676,700 20,355 Less imputed interest (83,678) (983) Total $ 1,593,022 $ 19,372
Schedule of supplemental cash flow information related to leases	June 30, Cash paid for amounts included in the measurement of lease liabilities: 2019 Operating cash flows from operating leases $ 558,900 Operating cash flows from finance leases 554 Financing cash flows from finance leases 4,756

Accounts Payable and Accrued _2

Accounts Payable and Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2019
Accounts Payable and Accrued Expenses
Schedule of components of accounts payable and accrued expenses	June 30, December 31, 2019 2018 Accrued research and development costs $ 12,137,333 $ 8,790,920 Accrued compensation 4,037,792 5,515,002 Accrued legal 1,382,760 687,042 Accrued commercial costs 5,401,483 4,614,507 Accrued general and administrative costs 1,408,942 1,545,591 Accrued sales deduction and allowance 1,109,480 — Accrued royalty 271,168 — Total accounts payable and accrued expenses $ 25,748,958 $ 21,153,062

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	6 Months Ended
	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss)
Schedule of changes in accumulated other comprehensive loss	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Balance at beginning of period $ (27,161) $ (150,377) $ (56,559) $ (145,958) Other comprehensive income before reclassification 79,649 27,404 104,723 19,088 Amounts reclassified from accumulated other comprehensive loss* — — 4,324 3,897 Total other comprehensive income 79,649 27,404 109,047 22,985 Balance at end of period $ 52,488 $ (122,973) $ 52,488 $ (122,973) *Amounts reclassified affect other income in the Statements of Operations.

Product revenue reserves and _2

Product revenue reserves and allowances (Tables)	6 Months Ended
	Jun. 30, 2019
Product revenue reserves and allowances
Schedule of product revenue reserves and allowances	Three Months Ended June 30, 2019 Commercial Co-payment Government Product Assistance Distribution Rebates Returns Programs Fees Total Beginning balance at March 31, 2019 $ 172,688 $ 202,769 $ 52,181 $ 142,672 $ 570,310 Provision related to sales in the current quarter 725,102 465,281 944 337,815 1,529,142 Adjustments related to prior period sale — — — — — Credits and payments made (416,394) (537,460) — (61,011) (1,014,865) Ending balance at June 30, 2019 $ 481,396 $ 130,590 $ 53,125 $ 419,476 $ 1,084,587 Six Months Ended June 30, 2019 Commercial Co-payment Government Product Assistance Distribution Rebates Returns Programs Fees Total Beginning balance at December 31, 2018 $ — $ — $ — $ — $ — Provision related to sales in the current year 897,790 668,050 53,125 480,487 2,099,452 Adjustments related to prior period sale — — — — — Credits and payments made (416,394) (537,460) — (61,011) (1,014,865) Ending balance at June 30, 2019 $ 481,396 $ 130,590 $ 53,125 $ 419,476 $ 1,084,587

Net Loss Per Common Share (Tabl

Net Loss Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2019
Net Loss Per Common Share
Schedule of computation of basic and diluted net loss per share	Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Basic and diluted net loss per common share calculation: Net loss $ (16,841,422) $ (18,928,703) $ (44,248,688) $ (37,345,456) Basic and diluted weighted-average common shares 40,108,267 28,567,982 38,836,664 27,851,707 Basic and diluted net loss per share $ (0.42) $ (0.66) $ (1.14) $ (1.34)
Schedule of total shares of stock options, restricted stock, and outstanding warrants that could potentially dilute earnings per share in the future, but which were not included in the calculation of diluted net loss per share because their effect would have been anti-dilutive	Six Months Ended June 30, 2019 2018 Restricted stock 3,427,168 1,926,706 Options outstanding 3,446,591 3,144,768 Total 6,873,759 5,071,474

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2019
Schedule of stock-based compensation by expense category	Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Research and development $ 3,221,426 $ 1,216,018 $ 6,327,485 $ 2,186,643 Selling, general and administrative 5,090,303 2,189,623 9,190,336 3,425,425 Total $ 8,311,729 $ 3,405,641 $ 15,517,821 $ 5,612,068
Schedule of stock-based compensation expense capitalized to inventory	Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Stock-based compensation expense capitalized to inventory $ 181,551 $ — $ 237,108 $ —
Schedule of weighted-average key assumptions used in determining the fair value of options granted	Three Months Ended Six Months Ended June 30, June 30, 2019 2018 2019 2018 Weighted-average volatility 65.94 % 77.27 % 66.23 % 77.53 % Weighted-average risk-free interest rate 2.22 % 2.82 % 2.42 % 2.75 % Weighted-average expected term in years 6.26 6.26 6.26 6.26 Dividend yield — — — —
Summary of activity related to the Company's stock options	Weighted- Average Weighted- Remaining Aggregate Average Contractual Intrinsic Options Exercise Price Life Value Outstanding at December 31, 2018 3,514,018 $ 9.59 Options granted Options exercised Options forfeited Outstanding at June 30, 2019 $ $ Options exercisable at June 30, 2019 $ $
Restricted Stock Awards
Summary of activity related to the Company's restricted stock	Weighted- Average Grant Date Fair Value Number of Shares Per Share Outstanding at December 31, 2018 2,794,455 $ 12.79 Shares granted 11.74 Shares vested 12.61 Shares forfeited 13.24 Outstanding at June 30, 2019 $ 12.33
Restricted Stock Units
Summary of activity related to the Company's restricted stock	Weighted- Average Grant Date Fair Value Number of Shares Per Unit Outstanding at December 31, 2018 — $ — Shares granted 14,000 13.29 Shares vested — — Shares forfeited — — Outstanding at June 30, 2019 14,000 $ 13.29

Organization and Basis of Pre_2

Organization and Basis of Presentation (Details) - USD ($)	3 Months Ended		6 Months Ended		191 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Organization and Basis of Presentation
Net loss	$ (16,841,422)	$ (18,928,703)	$ (44,248,688)	$ (37,345,456)	$ (345,000,000)
Minimum term for which anticipated operating cash requirements are funded			12 months

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Leases (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
New ASUs
Operating lease right of use asset	$ 1,469,714
Operating lease liability	$ 1,593,022
Restatement adjustment | ASU 2016-02
New ASUs
Operating lease right of use asset		$ 2,000,000
Operating lease liability		$ 2,000,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - ASU 2018-07 $ in Millions	Jun. 30, 2019USD ($)
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity
Decrease to accumulated deficit	$ (0.2)
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity
Decrease to accumulated deficit	$ 0.2

Liquidity and Capital Resourc_2

Liquidity and Capital Resources (Details) $ in Millions	Jun. 30, 2019USD ($)
Liquidity and Capital Resources
Cash, cash equivalents, short and long-term investment balance	$ 103.9

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Prepaid Expenses and Other Current Assets
Prepaid third party vendor costs	$ 1,714,355	$ 1,851,553
Deposits	492,794	189,000
Prepaid insurance	612,768	69,021
Other receivable	776,519	843,422
Total	$ 3,596,436	$ 2,952,996

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property and Equipment, Net
Office furniture and fixtures	$ 519,675		$ 519,675
Manufacturing equipment	181,753		107,258
Leasehold improvements	82,694		82,694
Capital lease equipment	29,529		29,529
Computer equipment	18,612		18,612
Property and equipment	832,263		757,768
Less accumulated depreciation and amortization	(593,534)		(535,355)
Property, plant and equipment-net	238,729		$ 222,413
Depreciation expense	$ 58,179	$ 24,064

Fair Value Measurements - Hiera

Fair Value Measurements - Hierarchy (Details) - Recurring basis - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Assets:
Fixed-income treasury portfolio	$ 86,918,164	$ 30,637,998
Certificate of Deposits		20,024,191
Cash and cash equivalents	16,965,619	9,443,667
Total assets at fair value	103,883,783	60,105,856
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets:
Fixed-income treasury portfolio	86,918,164	30,637,998
Cash and cash equivalents	16,965,619	9,443,667
Total assets at fair value	$ 103,883,783	40,081,665
Significant Other Observable Inputs (Level 2)
Assets:
Certificate of Deposits		20,024,191
Total assets at fair value		$ 20,024,191

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Cash Equivalents and Available-for-Sale Investments Held (Details) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities
Total Gross Unrealized Gains	$ 110,631	$ 767
Total Gross Unrealized Losses	(3,859)	(32,030)
Short-term investments
Available-for-sale securities
Amortized Cost	86,811,392	50,693,452
Gross Unrealized Gains	110,631	767
Gross Unrealized Losses	(3,859)	(32,030)
Estimated Fair Value	$ 86,918,164	$ 50,662,189
Short-term investments | Maximum
Available-for-sale securities
Remaining contractual maturity	12 months	12 months
Short-term investments | Fannie Mae
Available-for-sale securities
Amortized Cost	$ 3,995,281	$ 2,013,336
Gross Unrealized Gains	3,849
Gross Unrealized Losses		(1,146)
Estimated Fair Value	3,999,130	2,012,190
Short-term investments | Federal home loan bank
Available-for-sale securities
Amortized Cost		6,020,492
Gross Unrealized Losses		(10,646)
Estimated Fair Value		6,009,846
Short-term investments | Federal farm credit bank
Available-for-sale securities
Amortized Cost	2,424,843
Gross Unrealized Gains	5,686
Estimated Fair Value	2,430,529
Short-term investments | Freddie Mac
Available-for-sale securities
Amortized Cost	2,254,081	2,512,252
Gross Unrealized Gains	820
Gross Unrealized Losses	(1,420)	(8,530)
Estimated Fair Value	2,253,481	2,503,722
Short-term investments | U.S. Treasury Securities
Available-for-sale securities
Amortized Cost	78,137,187	20,123,026
Gross Unrealized Gains	100,276	767
Gross Unrealized Losses	(2,439)	(11,553)
Estimated Fair Value	78,235,024	20,112,240
Short-term investments | Certificate of Deposits
Available-for-sale securities
Amortized Cost		20,024,346
Gross Unrealized Losses		(155)
Estimated Fair Value		20,024,191
Amortized Cost
Available-for-sale securities
Total cash and cash equivalents	16,965,619	9,443,667
Estimated Fair Value
Available-for-sale securities
Total cash and cash equivalents	16,965,619	9,443,667
Total	103,883,783	60,105,856
Amortized Cost
Available-for-sale securities
Total	103,777,011	60,137,119
Cash from operating accounts | Amortized Cost
Available-for-sale securities
Cash	10,882,887	2,482,621
Cash from operating accounts | Estimated Fair Value
Available-for-sale securities
Cash	10,882,887	2,482,621
Money market funds | Amortized Cost
Available-for-sale securities
Cash equivalents	6,082,732	6,961,046
Money market funds | Estimated Fair Value
Available-for-sale securities
Cash equivalents	$ 6,082,732	$ 6,961,046

Fair Value Measurements - Avail

Fair Value Measurements - Available-for-Sale Securities in Continuous Loss Position (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Fair Value Measurements
Available-for-sale securities in a continuous unrealized loss position for greater than twelve months	$ 0	$ 0

Inventory (Details)

Inventory (Details)	6 Months Ended
	Jun. 30, 2019USD ($)
Inventory
Raw materials	$ 39,820
Work-in-process	3,297,314
Finished goods	317,883
Total Inventory	3,655,017
Write downs for excess and obsolete inventory	$ 0

Leases - Components of lease ex

Leases - Components of lease expense and other information (Details) - USD ($)	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Lease Expense
Operating Lease Cost	$ 529,385
Financing Lease Cost:
Amortization of right-of-use assets	4,920
Interest on lease liability	554
Total financing lease cost	5,474
Total Lease Cost	534,859
Operating Leases
Operating right-of-use asset, net	1,469,714
Operating right-of-use liability - current portion	1,042,526
Operating right-of-use liability	550,496
Total Operating lease liabilities	1,593,022
Financing Leases
Property, plant and equipment	832,263	$ 757,768
Accumulated depreciation	(593,534)	(535,355)
Property, plant and equipment-net	238,729	$ 222,413
Other current liabilities	9,876
Other liabilities	9,496
Total Financing lease liabilities	$ 19,372
Weighted Average Remaining Lease Term-Operating Leases	1 year 6 months
Weighted Average Remaining Lease Term -Financing Leases	1 year 11 months 1 day
Weighted Average Discount Rate-Operating Leases	7.32%
Weighted Average Discount Rate-Financing Leases	5.00%
Financing Leases
Financing Leases
Property, plant and equipment	$ 29,529
Accumulated depreciation	(10,663)
Property, plant and equipment-net	$ 18,866

Leases - Future minimum lease p

Leases - Future minimum lease payments (Details)	6 Months Ended
	Jun. 30, 2019USD ($)
Operating Leases
2019	$ 558,900
2020	1,117,800
Total future minimum lease payments	1,676,700
Less imputed interest	(83,678)
Total Operating lease liabilities	1,593,022
Finance Lease Liabilities, Payments, Due [Abstract]
2019	5,310
2020	10,620
2021	4,425
Total future minimum lease payments	20,355
Less imputed interest	(983)
Total Financing lease liabilities	19,372
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	558,900
Operating cash flows from finance leases	554
Financing cash flows from finance leases	$ 4,756

Accounts Payable and Accrued _3

Accounts Payable and Accrued Expenses (Details) - USD ($)	Jun. 30, 2019	Dec. 31, 2018
Accounts Payable and Accrued Expenses
Accrued research and development costs	$ 12,137,333	$ 8,790,920
Accrued compensation	4,037,792	5,515,002
Accrued legal	1,382,760	687,042
Accrued commercial costs	5,401,483	4,614,507
Accrued general and administrative Costs	1,408,942	1,545,591
Accrued sales deduction and allowance	1,109,480
Accrued royalty	271,168
Total accounts payable and accrued expenses	$ 25,748,958	$ 21,153,062

Common Stock (Details)

Common Stock (Details)	Jan. 18, 2019USD ($)$ / sharesshares	Jun. 30, 2019USD ($)Voteshares	Jun. 30, 2018USD ($)	Dec. 31, 2018shares
Proceeds from follow-on public offering net of underwriting fees and offering expenses | $		$ 86,218,630	$ 63,968,817
Number of shares of common stock authorized to be issued | shares		83,750,000		53,750,000
Number of votes to which holders of common shares are entitled for each share held | Vote		1
Follow on Public Offering
Shares sold (in shares) | shares	8,888,889
Share price (in dollars per share) | $ / shares	$ 9
Over-allotment Option
Proceeds from follow-on public offering net of underwriting fees and offering expenses | $	$ 86,200,000
Share price (in dollars per share) | $ / shares	$ 9
Number of shares issued pursuant to an option granted to the underwriters to cover over-allotments | shares	1,333,333
Aggregate gross proceeds from public offering | $	$ 92,000,000

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period	$ (27,161)	$ (150,377)	$ (56,559)	$ (145,958)
Other comprehensive income before reclassification	79,649	27,404	104,723	19,088
Amounts reclassified from accumulated other comprehensive loss			4,324	3,897
Total other comprehensive income	79,649	27,404	109,047	22,985
Balance at end of period	$ 52,488	$ (122,973)	$ 52,488	$ (122,973)

Product revenue reserves and _3

Product revenue reserves and allowances (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Product revenue reserves and allowances
Beginning balance	$ 570,310
Provision related to sales in the current year	1,529,142	$ 2,099,452
Credits and payments made	(1,014,865)	(1,014,865)
Ending balance	1,084,587	1,084,587
Government Rebates
Product revenue reserves and allowances
Beginning balance	172,688
Provision related to sales in the current year	725,102	897,790
Credits and payments made	(416,394)	(416,394)
Ending balance	481,396	481,396
Product Returns
Product revenue reserves and allowances
Beginning balance	202,769
Provision related to sales in the current year	465,281	668,050
Credits and payments made	(537,460)	(537,460)
Ending balance	130,590	130,590
Commercial Co-payment Assistance Programs
Product revenue reserves and allowances
Beginning balance	52,181
Provision related to sales in the current year	944	53,125
Ending balance	53,125	53,125
Distribution Fees
Product revenue reserves and allowances
Beginning balance	142,672
Provision related to sales in the current year	337,815	480,487
Credits and payments made	(61,011)	(61,011)
Ending balance	$ 419,476	$ 419,476

Net Loss Per Common Share - Bas

Net Loss Per Common Share - Basic and Diluted (Details) - USD ($)	3 Months Ended		6 Months Ended		191 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Basic and diluted net loss per common share calculation:
Net loss	$ (16,841,422)	$ (18,928,703)	$ (44,248,688)	$ (37,345,456)	$ (345,000,000)
Basic and diluted weighted-average common shares	40,108,267	28,567,982	38,836,664	27,851,707
Basic and diluted net loss per share (in dollars per share)	$ (0.42)	$ (0.66)	$ (1.14)	$ (1.34)

Net Loss Per Common Share - Ant

Net Loss Per Common Share - Anti-dilutive Securities (Details) - shares	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Net (Loss) Income per Common Share
Potentially dilutive securities excluded from the computation of earnings per share (in shares)	6,873,759	5,071,474
Restricted Stock Awards
Net (Loss) Income per Common Share
Potentially dilutive securities excluded from the computation of earnings per share (in shares)	3,427,168	1,926,706
Options outstanding
Net (Loss) Income per Common Share
Potentially dilutive securities excluded from the computation of earnings per share (in shares)	3,446,591	3,144,768

Grant Income (Details)

Grant Income (Details) - Leukemia and Lymphoma Society - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Oct. 31, 2013	Jun. 30, 2019
Grant Income
Maximum amount of grants to be received from the Leukemia and Lymphoma Society	$ 3.5
Grant proceeds received		$ 3.5

Income Taxes (Details)

Income Taxes (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018
Income Taxes
Income tax benefit	$ 18,500	$ 22,194	$ 0

Stock-Based Compensation - Equi

Stock-Based Compensation - Equity Incentive Plan (Details) - 2016 Plan - shares	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Option Plan
Number of common stock shares initially authorized for grant	1,812,932
Increase in number of authorized shares	2,500,000	2,900,000	1,200,000
Number of options with terms in excess of 10 years	0
Term of option	10 years
Shares available for future grants	2,624,469

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense Category (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock-Based Compensation
Stock-based compensation expense	$ 8,311,729	$ 3,405,641	$ 15,517,821	$ 5,612,068
Stock-based compensation expense capitalized to inventory	181,551		237,108
Research and development
Stock-Based Compensation
Stock-based compensation expense	3,221,426	1,216,018	6,327,485	2,186,643
Selling, general and administrative
Stock-Based Compensation
Stock-based compensation expense	$ 5,090,303	$ 2,189,623	$ 9,190,336	$ 3,425,425

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Options (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Weighted average assumptions used to estimate the weighted average fair value of the options granted on the date of grant using the Black-Scholes option-pricing model
Proceeds from exercise of stock options			$ 293,490	$ 1,533,323
Options outstanding
Stock-Based Compensation
Term of option			10 years
Weighted average assumptions used to estimate the weighted average fair value of the options granted on the date of grant using the Black-Scholes option-pricing model
Weighted-average volatility (as a percent)	65.94%	77.27%	66.23%	77.53%
Weighted-average risk-free interest rate (as a percent)	2.22%	2.82%	2.42%	2.75%
Weighted-average expected term in years	6 years 3 months 4 days	6 years 3 months 4 days	6 years 3 months 4 days	6 years 3 months 4 days
Dividends paid to stockholders			$ 0
Proceeds from exercise of stock options			300,000
Unrecognized compensation expense related to unvested stock options	$ 5,900,000		$ 5,900,000
Weighted average period over which unrecognized compensation expense is expected to be recognized			2 years 3 months 26 days
Options
Outstanding balance at the beginning of the year (in shares)			3,514,018
Options granted (in shares)			85,500
Options exercised (in shares)			(74,721)
Options forfeited (in shares)			(78,206)
Outstanding balance at the end of the year (in shares)	3,446,591		3,446,591
Options exercisable (in shares)	2,570,019		2,570,019
Weighted-Average Exercise Price
Outstanding balance at the beginning of the year (in dollars per share)			$ 9.59
Options granted (in dollars per share)			12.38
Options exercised (in dollars per share)			4.34
Options forfeited (in dollars per share)			11.39
Outstanding balance at the end of the year (in dollars per share)	$ 9.73		9.73
Options exercisable (in dollars per share)	$ 9.10		$ 9.10
Weighted-Average Remaining Contractual Life
Outstanding balance (in years)			5 years 8 months 1 day
Options exercisable (in years)			4 years 9 months
Aggregate Intrinsic Value
Outstanding balance (in dollars)	$ 22,184,838		$ 22,184,838
Options exercisable (in dollars)	$ 18,550,445		$ 18,550,445
Options outstanding | Employees
Stock-Based Compensation
Vesting period			4 years
Options outstanding | Directors
Stock-Based Compensation
Vesting period			3 years

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Aug. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock-Based Compensation
Stock-based compensation expense		$ 8,311,729	$ 3,405,641	$ 15,517,821	$ 5,612,068
Non-employees
Stock-Based Compensation
Stock-based compensation expense				300,000	1,100,000
Performance Share Awards
Stock-Based Compensation
Stock-based compensation expense				400,000	37,514
Additional stock-based compensation expense				$ 5,100,000	0
Number of years for the treatment of BPDCN in adults and in pediatric patients	2 years
Restricted Stock Awards
Number of Shares
Outstanding balance at the beginning of the year (in shares)				2,794,455
Shares granted				1,623,471
Shares vested				(945,662)
Shares forfeited				(45,096)
Outstanding balance at the end of the year (in shares)		3,427,168		3,427,168
Weighted-Average Grant Date Fair Value Per Share
Outstanding balance at the beginning of the year (in dollars per share)				$ 12.79
Shares granted (in dollars per share)				11.74
Shares vested (in dollars per share)				12.61
Shares forfeited (in dollars per share)				13.24
Outstanding balance at the end of the year (in dollars per share)		$ 12.33		$ 12.33
Total aggregate fair value of stock granted				$ 19,100,000
Unrecognized compensation expense adjusted for estimated forfeitures, related to unvested restricted stock		$ 32,500,000		$ 32,500,000
Remaining weighted-average period for recognizing unrecognized compensation cost				1 year 9 months 29 days
Total fair value of shares vested				$ 11,900,000	$ 4,100,000
Restricted Stock Awards | Directors
Stock-Based Compensation
Vesting period				3 years
Restricted Stock Awards | Maximum
Stock-Based Compensation
Vesting period				4 years
Restricted Stock Units
Stock-Based Compensation
Vesting period				4 years
Number of Shares
Shares granted				14,000
Outstanding balance at the end of the year (in shares)		14,000		14,000
Weighted-Average Grant Date Fair Value Per Share
Shares granted (in dollars per share)				$ 13.29
Outstanding balance at the end of the year (in dollars per share)		$ 13.29		$ 13.29
Total aggregate fair value of stock granted				$ 200,000
Unrecognized compensation expense adjusted for estimated forfeitures, related to unvested restricted stock		$ 200,000		$ 200,000
Remaining weighted-average period for recognizing unrecognized compensation cost				3 years 11 months 12 days
Total fair value of shares vested				$ 0

Stock-Based Compensation - Empl

Stock-Based Compensation - Employee Stock Purchase Plan (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock-Based Compensation
Stock-based compensation expense	$ 8,311,729	$ 3,405,641	$ 15,517,821	$ 5,612,068
2015 Employee Stock Purchase Plan
Stock-Based Compensation
Stock-based compensation expense			$ 70,353	$ 25,350
2015 Employee Stock Purchase Plan | Minimum
Stock-Based Compensation
Purchase price expressed as percentage of fair market value of common stock on grant date or date of exercise			85.00%
Purchase discount			5.00%

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019USD ($)
Leukemia and Lymphoma Society
Contractual Agreements
Maximum amount of fund receivable	$ 3.5
Grant proceeds received	3.5
Expense relating to the achievement of a post-approval milestone	4.4
Research and development agreements with third parties
Commitments and contingencies
Amount required to be paid upon achievement of certain milestones	375.6
Amount paid or accrued	7.9
Contractual agreement and pharmaceutical drug substance manufacturer
Contractual Agreements
Contractual agreement value	$ 33.6
Contractual agreement term	6 years
New Service Agreements
Contractual Agreements
Amount paid	$ 28.6
Clinical programs with Clinical research organizations (CROs)
Contractual Agreements
Contractual agreement value	$ 1.6