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DEI Document - $ / shares	3 Months Ended
DEI Document - $ / shares	Mar. 31, 2019	Apr. 30, 2019
Document and Entity Information [Abstract]
Entity Registrant Name	XERIS PHARMACEUTICALS INC
Entity Central Index Key	0001346302
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Amendment Flag	false
Trading Symbol	XERS
Entity Listing, Par Value Per Share	$ 0.0001
Entity Common Stock, Shares Outstanding		26,940,229

Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current Assets
Cash and cash equivalents	$ 61,984	$ 45,716
Short-term Investments	85,687	66,917
Accounts receivable, net	3,628	2,869
Prepaid expenses and other current assets	2,146	2,397
Total current assets	153,445	117,899
Property and equipment, net	7,430	2,034
Other assets	95	95
Total assets	160,970	120,028
Current Liabilities
Accounts payable	1,408	866
Accrued expenses	11,482	8,214
Warrants liabilities	295	860
Deferred grant awards	221	232
Total current liabilities	13,406	10,172
Long-term debt, net of unamortized deferred costs	32,141	31,890
Other long-term liabilities	8,323	2,560
Total liabilities	53,870	44,622
Commitments and Contingencies (Note 8)
Stockholders' Equity
Preferred Stock, par value $0.0001	0	0
Common stock, par value $0.0001	3	2
Additional paid in capital	253,040	196,121
Accumulated deficit	(145,942)	(120,665)
Accumulated other comprehensive loss	(1)	(52)
Total stockholders' equity	107,100	75,406
Total liabilities and stockholders' equity	$ 160,970	$ 120,028

Condensed Balance Sheets Balance Sheets Parenthetical - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Preferred Stock, Par Value Per Share	$ 0.0001	$ 0.0001
Common Shares, Par Value Per Share	$ 0.0001	$ 0.0001
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Shares Authorized	150,000,000	150,000,000
Preferred Stock, Shares Issued	0	0
Common Stock, Shares, Issued	26,880,209	20,808,366

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Grant income	$ 215	$ 210
Service revenue	33	53
Cost of revenue	0	42
Gross Profit	248	221
Operating expenses
Research and development	13,167	8,712
Selling, general and administrative	12,518	3,239
Expense from operations	25,685	11,951
Loss from operations	(25,437)	(11,730)
Other income (expense)
Interest income	671	96
Interest expense	(1,063)	(191)
Change in fair market value of warrants	552	(82)
Other income (expense)	160	(177)
Net loss	(25,277)	(11,907)
Other comprehensive loss, net of tax
Unrealized gains on short-term investments	51	0
Comprehensive loss	$ (25,226)	$ (11,907)
Net loss per common share - basic and diluted	$ (1.07)	$ (5.49)
Weighted average common shares outstanding, basic and diluted	23,561,193	2,169,576

Condensed Statements of Stockholders' Equity (Deficit) Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]
Common Stock, Shares, Issued		2,159,068
Common Stock, Value, Issued		$ 1
Additional paid in capital			$ 2,754
Accumulated other comprehensive loss	$ 0
Accumulated deficit	(60,585)
Stockholders' Equity Attributable to Parent	(57,830)
Net loss	(11,907)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		39,510
Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options	51		51
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	244		244
Unrealized gains on short-term investments	0
Common Stock, Shares, Issued		2,198,578
Common Stock, Value, Issued		$ 1
Additional paid in capital			3,049
Accumulated other comprehensive loss	0
Accumulated deficit	(72,492)
Stockholders' Equity Attributable to Parent	$ (69,442)
Common Stock, Shares, Issued	20,808,366	20,808,366
Common Stock, Value, Issued	$ 2	$ 2
Additional paid in capital	196,121		196,121
Accumulated other comprehensive loss	(52)
Accumulated deficit	(120,665)
Stockholders' Equity Attributable to Parent	75,406
Net loss	(25,277)
Stock Issued During Period, Shares, New Issues		5,996,775
Stock Issued During Period, Value, Conversion of Convertible Securities		$ 1
Stock Issued During Period, Value, New Issues	55,632		55,631
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		72,797
Adjustments to Additional Paid in Capital, Share-based Compensation and Exercise of Stock Options	128		128
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	1,147		1,147
Unrealized gains on short-term investments	$ 51
Warrants, exercises in period	2,271
Warrants, exercises in period, value	$ 13		13
Common Stock, Shares, Issued	26,880,209	26,880,209
Common Stock, Value, Issued	$ 3	$ 3
Additional paid in capital	253,040		$ 253,040
Accumulated other comprehensive loss	(1)
Accumulated deficit	(145,942)
Stockholders' Equity Attributable to Parent	$ 107,100

Condensed Statements of Stockholders' Equity (Deficit) Parenthetical (Parentheticals)	3 Months Ended
	Mar. 31, 2019 USD ($)
Condensed Statements of Stockholders' Equity (Deficit) [Abstract]
Total costs for the issuance of common stock from public offering	$ 4,338,000

Statement of Cash Flows - USD ($)	3 Months Ended
Statement of Cash Flows - USD ($)	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net loss	$ (25,277,000)	$ (11,907,000)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	134,000	63,000
Amortization of short-term investments	(194,000)	0
Amortization of debt issuance costs	251,000	40,000
Stock-based compensation	1,147,000	244,000
Change in fair market value of warrants	(552,000)	82,000
Changes in operating assets and liabilities
Accounts receivable	(31,000)	912,000
Prepaid expenses and other current assets	251,000	(629,000)
Other assets	0	67,000
Accounts payable	542,000	(1,130,000)
Accrued expenses	2,452,000	4,402,000
Deferred grant awards	(11,000)	51,000
Deferred rent	102,000	0
Other liabilities	32,000	0
Net cash used in operating activities	(21,154,000)	(7,805,000)
Cash flows from investing activities
Purchases of property and equipment	(200,000)	(333,000)
Purchases of short-term investments	(37,815,000)	0
Sales and maturities of short-term investments	19,290,000	0
Net cash used in investing activities	(18,725,000)	(333,000)
Cash flows from financing activities
Proceeds from the issuance of common stock from public offering	59,969,000	0
Payments of public offering costs	(3,894,000)	0
Proceeds from sale of Series C Preferred Stock	0	4,438,000
Payments for Series C Preferred Stock offering costs	0	(24,000)
Proceeds from issuance of long-term debt	0	20,000,000
Payments of debt issuance costs	0	(238,000)
Proceeds from exercise of stock awards	72,000	27,000
Net cash provided by financing activities	56,147,000	24,203,000
Increase in cash and cash equivalents	16,268,000	16,065,000
Cash and cash equivalents, beginning of period	45,716,000	42,045,000
Cash and cash equivalents, end of period	61,984,000	58,110,000
Supplemental schedule of cash flow information
Cash paid for interest	533,000	5,000
Supplemental schedule of non-cash investing and financing activities
Tenant improvements	5,508,000	0
Accrued debt issuance costs	2,325,000	1,425,000
Deferred public offering costs within accrued expenses	444,000	582,000
Allocation of debt proceeds to warrants	0	326,000
Vesting of early exercised awards	$ 56,000	$ 24,000

Note 1. Organization and Nature of the Business	3 Months Ended
Note 1. Organization and Nature of the Business	Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of the Business	Organization and Nature of the Business Nature of business Xeris Pharmaceuticals, Inc. ("Xeris" or the "Company") is a specialty pharmaceutical company that was incorporated in Delaware in 2005. Xeris is dedicated to the development of ready-to-use injectable and infusible drug formulations that address important unmet medical needs, are easier to use by patients, caregivers and health practitioners, and reduce costs for payors and the healthcare system. Basis of presentation The financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Since its inception, the Company has devoted substantially all of its efforts to research and development, regulatory and technical activities. The Company has financed its operations through the issuance of its common stock, convertible preferred stock and other equity instruments, debt financing and grant funding from the National Institutes of Health ("NIH") and other philanthropic organizations. The Company has not generated any revenue from product sales. The Company has incurred operating losses since inception and has an accumulated deficit of $145.9 million as of March 31, 2019. The Company expects to continue to incur net losses for the next several years. Based on the Company’s current operating plans and existing working capital at March 31, 2019, cash resources are sufficient to sustain operations and capital expenditure requirements for at least the next 12 months. The Company is subject to a number of risks similar to other specialty pharmaceutical companies, including, but not limited to, successful development and commercialization of its drug candidates, the development of new technological innovations by its competitors, protection of intellectual property and market acceptance of the Company’s products.

Note 2. Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Summary of Significant Accounting Policies

The accompanying unaudited interim financial statements have been prepared in conformity with GAAP. Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).

In the opinion of management, the accompanying unaudited interim financial statements include all normal and recurring adjustments (which consist primarily of accruals and estimates that impact the financial statements) considered necessary to present fairly the Company’s financial position as of March 31, 2019 and its results of operations and cash flows for the three months ended March 31, 2019 and 2018. Operating results for the three-month period ended March 31, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019. The unaudited interim financial statements, presented herein, do not contain the required disclosures under GAAP for annual financial statements. The accompanying unaudited interim financial statements should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2018 included in the Company's Annual Report on Form 10-K filed with the SEC on March 6, 2019.

Use of estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, contingent liabilities and expenses included in the financial statements and accompanying notes. Actual results could differ from those estimates.

Debt issuance costs

Long-term debt is accounted for at amortized cost. Debt issuance costs incurred in connection with financing arrangements are amortized to interest expense over the life of the respective financing arrangement using the effective interest method. Debt issuance costs, net of related amortization, are deducted from the carrying value of the related debt.

Equity financing costs

The Company capitalizes costs that are directly associated with in-process equity financings until such financings are consummated, at which time such costs are recorded in the additional paid in capital line on the balance sheet against the gross proceeds of the equity financings.

Fair value of financial instruments

Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments be made. Additionally, fair value is used on a non-recurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, and accounts payable, are shown at cost, which approximates fair value due to the short-term nature of these instruments. The debt outstanding under the Loan and Security Agreement approximates fair value due to the variable interest rate on the debt. Items measured at fair value on a recurring basis include the Company’s short-term investments and warrants.

Net loss per common share

Basic and diluted net loss per common share is determined by dividing net loss applicable to common stockholders by the weighted average common shares outstanding during the period. For all periods presented, the outstanding shares of the preferred stock, warrants, and stock option awards have been excluded from the calculation because their effects would be anti-dilutive. Therefore, the weighted average common shares outstanding used to calculate both basic and diluted loss per common share are the same.

The following potentially dilutive securities (shown below in common stock equivalent shares) were excluded from the computation of diluted weighted average common shares outstanding due to their anti-dilutive effect:



	March 31,
	2019	2018
Convertible preferred stock	—	11,837,073
Vested and unvested stock options	4,210,559	2,364,278
Restricted stock units	125,000	—
Warrants	96,999	73,651
	4,432,558	14,275,002

New accounting pronouncements

Recently issued accounting pronouncements

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The new standard requires lessees to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of their classification. Leases will be classified as either operating or finance leases under the new guidance. Operating leases will result in straight-line expense in the income statement, similar to current operating leases, and finance leases will result in more expense being recognized in the earlier years of the lease term, similar to current capital leases. As an emerging growth company, ASU 2016-02 will be effective for the Company starting with the quarter ending March 31, 2020. Early adoption is permitted. The Company is currently evaluating the impact the adoption of this new standard will have on the financial statements and related disclosures; however, since the Company is a lessee to certain leases for property whose terms exceed twelve months, it expects to report assets and liabilities related to these leases on the financial statements that have not been previously reported once adopted.

Note 3. Reverse Stock Split and Initial Public Offering

3 Months Ended

Mar. 31, 2019

Reverse Stock Split and Initial Public Offering [Abstract]

Reverse Stock Split and Initial Public Offering

Reverse Stock Split and Public Stock Offerings

On June 8, 2018, the Company effectuated a 1-for-1.78112 reverse stock split of its outstanding common stock, which was approved by the Company’s board of directors on May 22, 2018 and by the Company’s stockholders on June 8, 2018. The reverse stock split resulted in an adjustment to the preferred stock conversion prices to reflect a proportional decrease in the number of shares of common stock to be issued upon conversion. The accompanying financial statements and notes to financial statements give retroactive effect to the reverse stock split for all periods presented. The shares of common stock retained a par value of $0.0001 per share. Accordingly, the stockholders’ equity reflects the reverse stock split by reclassifying from common stock to additional paid in capital an amount equal to the par value of the decreased shares resulting from the reverse stock split.

On June 25, 2018, the Company closed the initial public offering ("IPO") of its common stock pursuant to a registration statement on Form S-1, as amended. The Company sold an aggregate of 6,555,000 shares of common stock under the registration statement at an IPO price of $15.00 per share, including 855,000 shares of common stock pursuant to the exercise of the underwriters’ option to purchase additional shares. Net proceeds from the IPO were $88.9 million, after deducting underwriting discounts and commissions, as well as other IPO expenses. Upon closing the IPO, all outstanding shares of the Company's Series A, B and C convertible preferred stock were converted into 11,837,073 shares of common stock.

On February 19, 2019, the Company completed a public offering of its common stock pursuant to a registration statement on Form S-1, as amended. The Company sold an aggregate of 5,996,775 shares of common stock at a price of $10.00 per share, including 116,775 shares of common stock pursuant to the exercise of the underwriters' option to purchase additional shares. Net proceeds from the public offering were approximately $55.6 million after deducting underwriting discounts and commissions, as well as other public offering expenses.

Warrants

In 2014 the Company issued 19,931 warrants (“2014 Warrants”) to certain investors. The 2014 Warrants allow each holder to purchase one share of common stock for $5.912. There have been 16,944 2014 Warrants exercised, and 2,987 2014 Warrants remain outstanding as of March 31, 2019.

As part of the Loan and Security Agreement discussed in Note 5, "Long-term Debt," in the notes to unaudited condensed financial statements, the Lenders receive warrants equal to 3.0% of the principal borrowing amounts concurrent with the borrowing. The warrants represent a right for the lender to purchase shares of the Company’s common stock at an initial exercise price of $11.169 per share. The Company issued 53,720 warrants ("Term A Warrants") upon the drawdown of the Term A Loan in February 2018, and the Company issued 40,292 warrants ("Term B Warrants") upon the drawdown of the Term B Loan in September 2018. There have been no exercises of Term A Warrants or Term B Warrants, and as such all 53,720 warrants and 40,292 warrants, respectively, were outstanding as of March 31, 2019.

Because the warrants are a freestanding instrument, indexed to the Company's stock, they do not meet the criteria for equity classification. Therefore, warrants are liability classified and subject to remeasurement at each reporting period until they are exercised, expired, or otherwise settled. The initial fair value of the warrant liability was recorded with a corresponding offset to deferred debt cost which is a reduction to the notional value of the debt.

The Company recognized a gain of $72,000, $274,000 and $206,000 upon the change in fair value of the warrants during the three months ended March 31, 2019 related to the 2014 Warrants, the Term A Warrants and the Term B Warrants, respectively. The Company recognized a loss of $(45,000) and $(37,000) upon the change in fair value of the warrants during the three months ended March 31, 2018 related to the 2014 Warrants and the Term A Warrants, respectively.

As of March 31, 2019, the following warrants were outstanding:



	Outstanding Warrants	Exercise Price per Warrant	Expiration Date

2014 Warrants	2,987	$5.912	August 2020
Term A Warrants	53,720	$11.169	February 2025
Term B Warrants	40,292	$11.169	September 2025
	96,999

Note 4. Accrued Expenses (Notes)

3 Months Ended

Mar. 31, 2019

Accrued Expenses [Abstract]

Accrued Expenses

Accrued expenses consist of the following:



(in thousands)	March 31, 2019		December 31, 2018

Accrued research costs	$	4,743	$	2,221
Accrued employee costs	2,127		4,326
Accrued marketing and selling costs	1,667		—
Accrued purchases of property and equipment	550		—
Accrued public offering costs	444		—
Accrued other costs	1,951		1,667
Accrued expenses	$	11,482	$	8,214

Note 5. Long-Term Debt

3 Months Ended

Mar. 31, 2019

Long-term Debt, Unclassified [Abstract]

Long-Term Debt

Long-term Debt

Senior Secured Loan Facility

In February 2018, the Company entered into the Loan and Security Agreement that provides a senior secured loan facility of up to an aggregate principal amount of $45.0 million. The first tranche was $20.0 million and was drawn down in February 2018 ("Term A Loan"). The second tranche was $15.0 million and was drawn down in September 2018 ("Term B Loan"). The third tranche is $10.0 million and is available beginning upon approval of the Company’s Gvoke HypoPen New Drug Application ("NDA") by the U.S. Food & Drug Administration (”FDA”) until the earlier of September 30, 2019 or the 30^th day following NDA approval by the FDA.

The interest rate under the Loan and Security Agreement is the thirty-day U.S. LIBOR rate plus 6.75%, which was approximately 9.24% as of March 31, 2019. Payments on the Loan and Security Agreement are interest only for the first 24 months, which can be extended by an additional twelve months if the third tranche is drawn. The total term of the loan is fifty-nine months, and the principal payments will begin in 24 months from the beginning of the term or, should the third tranche be drawn, 36 months from the beginning of the term.

Pursuant to the Loan and Security Agreement, the Company provided a first priority security interest in all existing and future-acquired assets, excluding intellectual property and certain other assets, owned by the Company. The Loan and Security Agreement contains a negative pledge on intellectual property owned by the Company. The Company also issued warrants to the Lenders to purchase common stock, which is further discussed in Note 7, "Warrants," of the notes to unaudited condensed financial statements.

The Loan and Security Agreement allows the Company to voluntarily prepay the outstanding amounts thereunder, but not less than $2.0 million of the outstanding principal at any time. Prior to April 1, 2020, the Company is subject to a prepayment penalty equal to 1.50% of the principal amount being prepaid. In the event the Company draws down the third tranche, the period subject to 1.50% prepayment is extended to April 1, 2021. No prepayment fee exists for prepayments made after April 1, 2020, or April 1, 2021 in the event the third tranche is issued. A final payment fee of 6.5% multiplied by the original principal amount of each tranche drawn is due upon the earlier to occur of the maturity date of the Loan and Security Agreement, the acceleration of the Loan and Security Agreement or prepayment of such borrowings. The Loan and Security Agreement includes a non-utilization fee of 2.0% multiplied by the principal amount of tranche three payable to Lenders in October 2019, if the Company elects not to draw the third tranche.

The Loan and Security Agreement also contains customary indemnification obligations and customary events of default, including, among other things, failure to fulfill certain obligations under the Loan and Security Agreement and the occurrence of a material adverse change in the Company's business, operations or condition, a material impairment of the prospect of repayment of any portion of the loan, or a material impairment in the perfection or priority of the Lenders’ lien in the collateral or in the value of such collateral. In the event of default under the Loan and Security Agreement, the Company would be required to pay interest on principal and all other due and unpaid obligations at the current rate in effect plus 5%. All such interest would be payable on demand and in cash. Further, the Lenders would be entitled to exercise their remedies thereunder, including the right to accelerate the debt, upon which the Company may be required to repay all amounts then outstanding under the Loan and Security Agreement.

The Loan and Security Agreement includes certain restrictions on, among other things, the Company’s ability to incur additional indebtedness, change the name or location of the business, merge with or acquire other entities, pay dividends or make other distributions to holders of the Company’s capital stock, make certain investments, engage in transactions with affiliates, create liens, open new deposit accounts, sell assets or pay subordinated debt.

The components of debt are as follows:



(in thousands)	March 31, 2019			December 31, 2018

Term A Loan	$	20,000		$	20,000
Term B Loan	15,000			15,000
Less unamortized deferred costs	(2,859		)	(3,110		)
Long-term debt	$	32,141		$	31,890

The following table sets forth the Company’s future minimum principal payments (in thousands):



2019	$	—
2020	9,000
2021	12,000
2022	12,000
2023	2,000
	$	35,000

The Company incurred total debt issuance costs of $3.7 million, which are reflected as a direct reduction to the term loan balance and are being amortized into interest expense over the life of the loan using the effective interest method. For the three months ended March 31, 2019 and 2018, the Company recognized interest expense of $1.1 million and $0.2 million, respectively, of which $251,000 and $40,000, respectively, was related to the amortization of debt issuance costs.

Note 6. Convertible Preferred Stock	3 Months Ended
Note 6. Convertible Preferred Stock	Mar. 31, 2019
Convertible preferred stock [Abstract]
Convertible Preferred Stock	Convertible Preferred Stock In February 2018, the Company issued an additional 707,680 shares of Series C convertible preferred stock for net proceeds of $4.4 million. During the second quarter of 2018, a majority of the holders of the Company's convertible preferred stock elected to have their shares converted into common stock; therefore, all outstanding shares of preferred stock were converted into 11,837,073 shares of common stock at a conversion rate of 1:1.78112 upon the closing of the Company's IPO on June 25, 2018. Prior to the conversion of the convertible preferred stock into common stock, the holders of the Company’s convertible preferred stock were entitled to receive non-cumulative dividends at the rate of 8% of the purchase price per annum in preference to any dividends to the holders of the common stock, payable as and if when declared by the Board of Directors. No such dividends were declared by the Company’s Board of Directors. The holders of the convertible preferred stock also were entitled to participate pro rata in any dividends paid to the holders of the common stock on an as-converted basis. No dividends were declared by the Company’s Board of Directors.

Note 7. Warrants (Notes)

3 Months Ended

Mar. 31, 2019

Warrants [Abstract]

Warrants

Reverse Stock Split and Public Stock Offerings

Warrants

As of March 31, 2019, the following warrants were outstanding:



	Outstanding Warrants	Exercise Price per Warrant	Expiration Date

2014 Warrants	2,987	$5.912	August 2020
Term A Warrants	53,720	$11.169	February 2025
Term B Warrants	40,292	$11.169	September 2025
	96,999

Note 8. Commitments and Contingencies	3 Months Ended
Note 8. Commitments and Contingencies	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments The Company has non-cancellable operating leases for office space, which expire at various times through 2031. The non-cancellable office lease agreements provide for monthly lease payments, which increase during the term of each lease agreement. In the first quarter of 2018, the Company signed a lease for office space in Chicago, Illinois. In the fourth quarter of 2018, the Company signed an amendment to this lease to occupy additional space and relocated from its existing premises to this additional space in March 2019. The future minimum lease payments of the amended lease are approximately $0 in 2019, $746,000 in 2020, $1,095,000 in 2021, $1,125,000 in 2022, $1,156,000 in 2023, and $9,747,000 in 2024 and thereafter. Total rent expense under these operating leases was approximately $487,000 and $191,000 for the three months ended March 31, 2019 and 2018, respectively

Note 9. Stock Compensation Plan (Notes)

3 Months Ended

Mar. 31, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Compensation Plan

In 2011 the Company adopted the 2011 Stock Option Issuance Plan (“2011 Plan”) and subsequently amended it to authorize the Board of Directors to issue up to 4,714,982 incentive grant and non-statutory awards.

The 2018 Stock Option and Incentive Plan ("2018 Plan") was adopted by the Board of Directors in April 2018 and approved by the Company's stockholders in June 2018 to award up to 1,822,000 shares of common stock. This plan became effective on the date immediately prior to the effectiveness of the Company's IPO registration statement. The 2018 Plan replaced the 2011 Plan as the Board of Directors determined not to make additional awards under the 2011 Plan following the closing of the IPO, which occurred in June 2018. The 2018 Plan allows the compensation committee to make equity-based and cash-based incentive awards to the Company's officers, employees, directors and other key persons (including consultants).

The 2018 Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2019, by 4% of the outstanding number of shares of our common stock on the immediately preceding December 31, or such lesser number of shares as determined by the compensation committee. This number is subject to adjustment in the event of a stock split, stock dividend or other change in the Company's capitalization. On January 1, 2019, the number of shares of common stock available for issuance under the 2018 Plan was automatically increased by 835,728 shares. As of March 31, 2019, there were approximately 840,000 shares of common stock available for future issuance under the 2018 Plan.

The 2018 Employee Stock Purchase Plan ("ESPP") was adopted by the Board of Directors in April 2018 and approved by the Company's stockholders in June 2018 to award up to 193,000 shares of common stock to participating employees. This plan became effective on the date immediately prior to the effectiveness of the Company's IPO registration statement. The ESPP provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2019 and each January 1 thereafter through January 1, 2028, by the least of (i) 1% of the outstanding number of shares of our common stock on the immediately preceding December 31; (ii) 386,000 shares or (iii) such lesser number of shares as determined by the ESPP administrator. On January 1, 2019, the number of shares of common stock available for issuance under the ESPP increased by 208,932 shares. As of March 31, 2019, there were 401,932 shares available for issuance under the ESPP. The number of shares reserved under the ESPP is subject to adjustment in the event of a stock split, stock dividend or other change in our capitalization.

The Equity Inducement Plan ("Inducement Plan"), was adopted by the Board of Directors in February 2019. The Inducement Plan was adopted without stockholder approval pursuant to Rule 5635(c)(4) of the Nasdaq Listing Rules. The Inducement Plan allows the Company to make stock option or restricted stock unit awards to prospective employees of the Company as an inducement to such individuals to commence employment with the Company. The Company intends to use this Inducement Plan to help it attract and retain prospective employees who are necessary to support the commercial launch of the Gvoke HypoPen and the expansion of the Company generally. The Company has initially reserved 750,000 shares of common stock for the issuance of awards under the Inducement Plan. This number is subject to adjustment in the event of a stock split, stock dividend or other change in our capitalization. As of March 31, 2019, there were 585,000 shares of common stock available for future issuance under the Inducement Plan.

Stock options are granted with an exercise price equal to the market price of the Company’s stock at the date of grant. Stock option awards typically vest over either two years or four years after the grant date and expire ten years from the grant date.

The fair value of each option is estimated on the date of grant using a Black-Scholes option valuation model that uses the assumptions noted in the following table. The expected life of options represents the period of time that options granted are expected to be outstanding. The risk-free interest rate for periods during the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant. The expected stock price volatility assumption is based on the historical volatilities of a peer group of publicly traded companies as well as the historical volatility of the Company's common stock since the Company began trading subsequent to its IPO in June 2018 over the period corresponding to the expected life as of the grant date. The expected dividend yield is based on the expected annual dividend as a percentage of the market value of the Company’s ordinary shares as of the grant date. The Company uses historical data to estimate option exercises and employee terminations within the valuation model.

The fair value of stock options granted was estimated with the following weighted average assumptions:



	Three Months Ended March 31,
	2019		2018
Expected term (years)	6.0		6.06
Risk-free interest rate	2.27	%	2.66	%
Expected volatility	60.63	%	58.57	%
Expected dividends	—		—

Stock option activity for employee awards under the 2011 Plan, 2018 Plan and Inducement Plan for the three months ended March 31, 2019 was as follows:



	Units	Weighted Average Exercise Price		Weighted Average Contractual Life (Years)
Outstanding - January 1, 2019	3,127,308	$	8.06	8.69
Granted	1,224,690	13.01
Exercised and vested	(72,446)	1.77
Forfeited	(84,534)	16.86
Outstanding - March 31, 2019	4,195,018	$	9.41	8.91
Exercisable - March 31, 2019	2,256,303	$	4.45	7.83
Vested and expected to vest at March 31, 2019	3,943,316	$	9.48	8.91

The weighted average fair value of awards granted during the three months ended March 31, 2019 was $5.18 per share. The total intrinsic value of options exercised during the three months ended March 31, 2019 was $0.6 million. The aggregate intrinsic value of awards vested and expected to vest as of March 31, 2019 was $13.2 million.

The Company also granted stock options to non-employees under the 2011 Plan and 2018 Plan. These awards are marked to fair value at the end of each reporting period until they vest. Stock option activity for these awards for the three months ended March 31, 2019 was as follows:



	Units	Weighted Average Exercise Price		Weighted Average Contractual Life (Years)
Outstanding - January 1, 2019	3,392	$	1.55	2.00
Granted	12,500	13.88
Exercised and vested	(351)	1.55
Outstanding - March 31, 2019	15,541	$	11.47	9.69
Exercisable - March 31, 2019	0	$	0.00	0.00
Vested and expected to vest at March 31, 2019	14,608	$	11.47	9.69

The aggregate intrinsic value of awards vested and expected to vest at March 31, 2019 was $24,000. The aggregate intrinsic value of awards exercisable as of March 31, 2019 was $0. The company recognized expense associated with these awards of $4,000 and $7,000 for the three months ended March 31, 2019 and 2018, respectively.

Stock option activity for restricted stock unit ("RSU") awards for the three months ended March 31, 2019 was as follows:



	Units	Weighted Average Exercise Price
Unvested balance - January 1, 2019	0	$	0.00
Granted	125,000	13.88
Unvested balance - March 31, 2019	125,000	$	13.88

Restricted stock unit awards are measured based on the fair market value of the underlying stock on the date of grant and recognized as expense on a straight-line basis over the employee’s requisite service period (generally the vesting period). As of March 31, 2019 there was $0.5 million of unrecognized stock-based compensation expense related to RSUs, which is expected to be recognized over the weighted-average remaining vesting period of 3.8 years.

The following table summarizes the reporting of total stock-based compensation expense resulting from employee and non-employee stock options:



	Three Months Ended March 31,
(in thousands)	2019		2018
Research and development	$	195	$	121
Selling, general and administrative	952		123
Total stock-based compensation expense	$	1,147	$	244

At March 31, 2019, there was a total of $19.6 million of unrecognized compensation expense that is expected to be recognized over a weighted average period of 2.19 years.

Note 10. Fair Value Measurement

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value Measurement

Fair Value Measurements

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value measurements are classified and disclosed in one of the following categories:

Level 1: Measured using unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities;

Level 2: Measured using quoted prices in active markets for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and

Level 3: Measured based on prices or valuation models that required inputs that are both significant to the fair value measurement and less observable from objective sources (i.e., supported by little or no market activity).

Fair value measurements are classified based on the lowest level of input that is significant to the measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, which may affect the valuation of the assets and liabilities and their placement within the fair value hierarchy levels. The determination of the fair values stated below takes into account the market for its financial assets and liabilities, the associated credit risk and other factors as required. The Company considers active markets as those in which transactions for the assets or liabilities occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

The following tables present the Company’s fair value hierarchy for those assets and liabilities measured at fair value as of March 31, 2019 and December 31, 2018:



(in thousands)	Total as of March 31, 2019		Level 1		Level 2		Level 3

Current Assets
Cash and cash equivalents:
Money market funds	$	61,984	$	61,984	$	—	$	—

Short-term investments:
U.S. government securities	$	10,593	$	10,593	$	—	$	—
Corporate securities	53,178		—		53,178		—
Agency securities	11,363		—		11,363		—
Commercial paper	10,553		10,553		—		—
Total short-term investments	$	85,687	$	21,146	$	64,541	$	—

Other Current Liabilities
Warrant liabilities	$	295	$	—	$	—	$	295



(in thousands)	Total as of December 31, 2018		Level 1		Level 2		Level 3

Current Assets
Cash and cash equivalents:
Money market funds	$	45,716	$	45,716	$	—	$	—

Short-term investments:
U.S. government securities	$	38,737	$	38,737	$	—	$	—
Corporate securities	15,066		—		15,066		—
Agency securities	11,931		—		11,931		—
Commercial paper	1,183		1,183		—		—
Total short-term investments	$	66,917	$	39,920	$	26,997	$	—

Other Current Liabilities
Warrant liabilities	$	860	$	—	$	—	$	860

The fair value of the Company’s warrant liabilities at inception and for subsequent mark-to-market fair value measurements is based on management’s valuation model and expected methods and timing of settlement. These estimates are prepared using models that consider various inputs including: (a) the Company’s estimated future cash flows, (b) time value, (c) current market conditions, and (d) other relevant economic measures.

The Company has determined that the warrant liabilities' fair values are Level 3 items within the fair value hierarchy. The following table presents the changes in the warrant liabilities:



(in thousands)
Balance at December 31, 2018	$	860
Exercise of warrants	(13)
Change in fair market value of warrants	(552)
Balance at March 31, 2019	$	295

There were no transfers between any of the levels of the fair value hierarchy during the three months ended March 31, 2019.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Note 11. Short-Term Investments (Notes)

3 Months Ended

Mar. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Short-term investments

Short-Term Investments

The Company classifies its investments in debt securities as short-term investments and available-for-sale. Debt securities are comprised of highly liquid investments with minimum “A” rated securities and, as of March 31, 2019 consist of U.S. Treasury and agency bonds and corporate entity commercial paper and securities with maturities of more than three months but less than one year at the date of purchase. Debt securities as of March 31, 2019 have an average maturity of 0.36 years. The debt securities are reported at fair value with unrealized gains or losses recorded in accumulated other comprehensive loss in the condensed balance sheets. Any differences between the cost and fair value of investments are represented by unrealized gains or losses. Refer to Note 10, "Fair Value Measurements," of the notes to unaudited condensed financial statements for information related to the fair value measurements and valuation methods utilized.

The following table represents the Company’s available-for-sale short-term investments by major security type as of March 31, 2019:



(in thousands)	Amortized Cost		Gross Unrealized Gains		Total Fair Value

Short-term investments:
Agency securities	$	11,350	$	13	$	11,363
Commercial paper	10,553		—		10,553
Corporate securities	53,155		23		53,178
U.S. government securities	10,578		15		10,593
Total short-term investments	$	85,636	$	51	$	85,687

The Company reviews available-for-sale investments for other-than-temporary impairment loss quarterly. The Company considers factors such as the duration, severity and the reason for the decline in value, the potential recovery period and our intent to sell. For debt securities, we also consider whether (i) it is more likely than not that the Company will be required to sell the debt securities before recovery of their amortized cost basis and (ii) the amortized cost basis cannot be recovered as a result of credit losses. During the quarter ended March 31, 2019, the Company did not recognize any other-than-temporary impairment losses. All marketable securities with unrealized losses have been in a loss position for less than twelve months.

Note 2. Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2019

Summary of Significant Accounting Policies [Abstract]

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share



	March 31,
	2019	2018
Convertible preferred stock	—	11,837,073
Vested and unvested stock options	4,210,559	2,364,278
Restricted stock units	125,000	—
Warrants	96,999	73,651
	4,432,558	14,275,002

Note 4. Accrued Expenses (Tables)

3 Months Ended

Mar. 31, 2019

Accrued Expenses [Abstract]

Accrued Expenses

Accrued expenses consist of the following:



(in thousands)	March 31, 2019		December 31, 2018

Accrued research costs	$	4,743	$	2,221
Accrued employee costs	2,127		4,326
Accrued marketing and selling costs	1,667		—
Accrued purchases of property and equipment	550		—
Accrued public offering costs	444		—
Accrued other costs	1,951		1,667
Accrued expenses	$	11,482	$	8,214

Note 5. Long-Term Debt (Tables)

3 Months Ended

Mar. 31, 2019

Long-term Debt, Unclassified [Abstract]

Schedule of Long-term Debt Instruments

The components of debt are as follows:



(in thousands)	March 31, 2019			December 31, 2018

Term A Loan	$	20,000		$	20,000
Term B Loan	15,000			15,000
Less unamortized deferred costs	(2,859		)	(3,110		)
Long-term debt	$	32,141		$	31,890

Schedule of Maturities of Long-term Debt

The following table sets forth the Company’s future minimum principal payments (in thousands):



2019	$	—
2020	9,000
2021	12,000
2022	12,000
2023	2,000
	$	35,000

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

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+ Details

Note 7. Warrants (Tables)

3 Months Ended

Mar. 31, 2019

Warrants [Abstract]

Schedule of Stockholders' Equity Note, Warrants or Rights

As of March 31, 2019, the following warrants were outstanding:



	Outstanding Warrants	Exercise Price per Warrant	Expiration Date

2014 Warrants	2,987	$5.912	August 2020
Term A Warrants	53,720	$11.169	February 2025
Term B Warrants	40,292	$11.169	September 2025
	96,999

- Definition

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

+ References + Details

Note 9. Stock Compensation Plan (Tables)

3 Months Ended

Mar. 31, 2019

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock-based Compensation Assumptions Used in Black-Scholes Option Valuation Model

The fair value of stock options granted was estimated with the following weighted average assumptions:



	Three Months Ended March 31,
	2019		2018
Expected term (years)	6.0		6.06
Risk-free interest rate	2.27	%	2.66	%
Expected volatility	60.63	%	58.57	%
Expected dividends	—		—

Employee Stock Option [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation, Activity

Stock option activity for employee awards under the 2011 Plan, 2018 Plan and Inducement Plan for the three months ended March 31, 2019 was as follows:



	Units	Weighted Average Exercise Price		Weighted Average Contractual Life (Years)
Outstanding - January 1, 2019	3,127,308	$	8.06	8.69
Granted	1,224,690	13.01
Exercised and vested	(72,446)	1.77
Forfeited	(84,534)	16.86
Outstanding - March 31, 2019	4,195,018	$	9.41	8.91
Exercisable - March 31, 2019	2,256,303	$	4.45	7.83
Vested and expected to vest at March 31, 2019	3,943,316	$	9.48	8.91



	Units	Weighted Average Exercise Price		Weighted Average Contractual Life (Years)
Outstanding - January 1, 2019	3,392	$	1.55	2.00
Granted	12,500	13.88
Exercised and vested	(351)	1.55
Outstanding - March 31, 2019	15,541	$	11.47	9.69
Exercisable - March 31, 2019	0	$	0.00	0.00
Vested and expected to vest at March 31, 2019	14,608	$	11.47	9.69

Stock option activity for restricted stock unit ("RSU") awards for the three months ended March 31, 2019 was as follows:



	Units	Weighted Average Exercise Price
Unvested balance - January 1, 2019	0	$	0.00
Granted	125,000	13.88
Unvested balance - March 31, 2019	125,000	$	13.88

Note 9. Stock Compensation Plan Stock-Based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

The following table summarizes the reporting of total stock-based compensation expense resulting from employee and non-employee stock options:



	Three Months Ended March 31,
(in thousands)	2019		2018
Research and development	$	195	$	121
Selling, general and administrative	952		123
Total stock-based compensation expense	$	1,147	$	244

Note 10. Fair Value Measurement (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation

The Company has determined that the warrant liabilities' fair values are Level 3 items within the fair value hierarchy. The following table presents the changes in the warrant liabilities:



(in thousands)
Balance at December 31, 2018	$	860
Exercise of warrants	(13)
Change in fair market value of warrants	(552)
Balance at March 31, 2019	$	295

There were no transfers between any of the levels of the fair value hierarchy during the three months ended March 31, 2019.

Note 10. Fair Value Measurement Fair Value Measurement (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]

The following tables present the Company’s fair value hierarchy for those assets and liabilities measured at fair value as of March 31, 2019 and December 31, 2018:



(in thousands)	Total as of March 31, 2019		Level 1		Level 2		Level 3

Current Assets
Cash and cash equivalents:
Money market funds	$	61,984	$	61,984	$	—	$	—

Short-term investments:
U.S. government securities	$	10,593	$	10,593	$	—	$	—
Corporate securities	53,178		—		53,178		—
Agency securities	11,363		—		11,363		—
Commercial paper	10,553		10,553		—		—
Total short-term investments	$	85,687	$	21,146	$	64,541	$	—

Other Current Liabilities
Warrant liabilities	$	295	$	—	$	—	$	295



(in thousands)	Total as of December 31, 2018		Level 1		Level 2		Level 3

Current Assets
Cash and cash equivalents:
Money market funds	$	45,716	$	45,716	$	—	$	—

Short-term investments:
U.S. government securities	$	38,737	$	38,737	$	—	$	—
Corporate securities	15,066		—		15,066		—
Agency securities	11,931		—		11,931		—
Commercial paper	1,183		1,183		—		—
Total short-term investments	$	66,917	$	39,920	$	26,997	$	—

Other Current Liabilities
Warrant liabilities	$	860	$	—	$	—	$	860

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Note 11. Short-Term Investments (Tables)

3 Months Ended

Mar. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Debt Securities, Available-for-sale

The following table represents the Company’s available-for-sale short-term investments by major security type as of March 31, 2019:



(in thousands)	Amortized Cost		Gross Unrealized Gains		Total Fair Value

Short-term investments:
Agency securities	$	11,350	$	13	$	11,363
Commercial paper	10,553		—		10,553
Corporate securities	53,155		23		53,178
U.S. government securities	10,578		15		10,593
Total short-term investments	$	85,636	$	51	$	85,687

Note 1. Organization and Nature of the Business Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Retained Earnings (Accumulated Deficit)	$ (145,942)	$ (120,665)		$ (72,492)	$ (60,585)
Proceeds from second tranche of the Loan and Security Agreement			$ 15,000

Note 2. Summary of Significant Accounting Policies Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,432,558	14,275,002
Convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	11,837,073
Vested and unvested stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,210,559	2,364,278
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	125,000	0
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	96,999	73,651

Note 3. Reverse Stock Split and Initial Public Offering Narrative (Details) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019 USD ($) $ / shares shares	Jun. 30, 2018 $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Feb. 19, 2019 $ / shares shares	Jun. 25, 2018 $ / shares shares
Reverse Stock Split and Initial Public Offering [Abstract]
Reverse Stock Split, Conversion Ratio		1.78112
Common Shares, Par Value Per Share \| $ / shares	$ 0.0001	$ 0.0001	$ 0.0001
Common Stock, Shares, Issued	26,880,209		20,808,366	5,996,775	6,555,000
Shares Issued, Price Per Share \| $ / shares				$ 10.00	$ 15.00
Common shares issued, due to exercise of underwriter option				116,775	855,000
Net Proceeds from Issuance Initial Public Offering \| $			$ 88.9
Shares of common stock issued, after preferred stock conversion		11,837,073
Net proceeds from issuance of public offering \| $	$ 55.6

Note 4. Accrued Expenses Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Accrued Expenses [Abstract]
Accrued research costs	$ 4,743	$ 2,221
Accrued employee costs	2,127	4,326
Accrued marketing and selling costs	1,667	0
Accrued purchases of property and equipment	550	0
Accrued public offering costs	444	0	$ 582
Accrued other costs	1,951	1,667
Accrued expenses	$ 11,482	$ 8,214

Note 5. Long-Term Debt Debt, Future Principal Payments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018
Debt Disclosure [Abstract]
Future principal payments, 2019	$ 0
Future principal payments, 2020	9,000
Future principal payments, 2021	12,000
Future principal payments, 2022	12,000
Future principal payments, 2023	2,000
Long-term Debt	$ 35,000	$ 20,000

Note 5. Long-Term Debt Narrative (Details) - USD ($)	3 Months Ended
Note 5. Long-Term Debt Narrative (Details) - USD ($)	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Sep. 30, 2018
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 45,000,000
Debt Instrument, Face Amount	$ 35,000,000	20,000,000
Proceeds from second tranche of the Loan and Security Agreement				$ 15,000,000
Additional expected proceeds from third tranche of the Loan and Security Agreement	$ 10,000,000
Interest rate, thirty-day LIBOR plus stated percentage	6.75%
Debt Instrument, Interest Rate, Stated Percentage	9.24%
Period debt payments are interest only	24 months
Debt Instrument, Term	59 months
Prepayment allowed per debt agreement	$ 2,000,000
Prepayment penalty percentage	1.50%
Final payment fee percentage	6.50%
Debt, non-utilization fee percentage	2.00%
In event of default, additional percentage plus current rate penalty	5.00%
Debt Issuance Costs, Gross	$ 3,700,000
Interest expense	1,063,000	191,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(2,859,000)		$ (3,110,000)
Long-term Debt	32,141,000		31,890,000
Amortization of debt issuance costs	$ 251,000	$ 40,000
Maximum [Member]
Debt Instrument [Line Items]
Principal payments on debt to begin	36 months
Minimum [Member]
Debt Instrument [Line Items]
Principal payments on debt to begin	24 months
Term A Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 20,000,000		20,000,000
Term B Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 15,000,000		$ 15,000,000

Note 6. Convertible Preferred Stock Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 shares	Jun. 30, 2018 shares	Mar. 31, 2018 USD ($) shares	Dec. 31, 2018 shares
Equity [Abstract]
Preferred Stock, Shares Issued	0		707,680	0
Proceeds from Issuance of Preferred Stock, Preference Stock, and Warrants \| $			$ 4.4
Shares of common stock issued, after preferred stock conversion		11,837,073
Reverse Stock Split, Conversion Ratio		1.78112
Preferred Stock, Dividend Rate, Percentage	8.00%

Note 7. Warrants Schedule of Stockholders' Equity Note, Warrants or Rights (Details)	3 Months Ended
	Mar. 31, 2019 $ / shares shares
Class of Warrant or Right [Line Items]
Warrants outstanding	96,999
2014 Warrants [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding	2,987
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares	$ 5.912
Investment Warrants Expiration Date	Aug. 31, 2020
Term A Warrants [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding	53,720
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares	$ 11.169
Investment Warrants Expiration Date	Feb. 28, 2025
Term B Warrants [Member]
Class of Warrant or Right [Line Items]
Warrants outstanding	40,292
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares	$ 11.169
Investment Warrants Expiration Date	Sep. 07, 2025

Note 7. Warrants Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2014
Class of Warrant or Right [Line Items]
Class of warrants, exercised			16,944
Warrants outstanding	96,999		96,999
Change in fair market value of warrants	$ 552	$ (82)
2014 Warrants [Member]
Class of Warrant or Right [Line Items]
Preferred stock and warrants issued during the period, shares				19,931
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 5.912		$ 5.912
Warrants outstanding	2,987		2,987
Change in fair market value of warrants	$ 72	$ (45)
Term A Warrants [Member]
Class of Warrant or Right [Line Items]
Preferred stock and warrants issued during the period, shares		53,720
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 11.169		$ 11.169
Warrants outstanding	53,720		53,720
Warrant coverage, equal to percent of principal borrowing amounts	3.00%		3.00%
Change in fair market value of warrants	$ 274	$ (37)
Term B Warrants [Member]
Class of Warrant or Right [Line Items]
Preferred stock and warrants issued during the period, shares	40,292
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 11.169		$ 11.169
Warrants outstanding	40,292		40,292
Change in fair market value of warrants	$ 206

Note 8. Commitments and Contingencies Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Remaining future minimum lease payments, 2019	$ 0
Remaining future minimum lease payments, 2020	746,000
Remaining future minimum lease payments, 2021	1,095,000
Remaining future minimum lease payments, 2022	1,125,000
Remaining future minimum lease payments, 2023	1,156,000
Remaining future minimum lease payments, 2024 and thereafter	9,747,000
Rent Expense, operating leases	487,000	$ 191,000
Unused letters of credit	$ 1,083,000

Note 9. Stock Compensation Plan Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Method Used (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 years 3 days	6 years 22 days
Risk-free interest rate	2.27%	2.66%
Expected volatility	60.63%	58.57%
Expected dividends	0.00%	0.00%
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	125,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	125,000		0

Note 9. Stock Compensation Plan Employee Stock Award Activity (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense from restricted stock units	$ 500,000
Non--employee stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	0
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 4,000	$ 7,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	15,541		3,392
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 11.47		$ 1.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	9 years 252 days		2 years
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	12,500
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 13.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(351)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 1.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	0 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	14,608
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 11.47
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term	9 years 252 days
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	4,195,018		3,127,308
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 9.41		$ 8.06
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	8 years 332 days		8 years 252 days
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	1,224,690
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 13.01
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(72,446)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 1.77
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares	(84,534)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 16.86
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	2,256,303
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 4.45
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	7 years 302 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	3,943,316
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price	$ 9.48
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term	8 years 332 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	125,000		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 13.88		$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	125,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 13.88
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 295 days

Note 9. Stock Compensation Plan Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 1,147	$ 244
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	195	121
Selling, General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 952	$ 123

Note 9. Stock Compensation Plan Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Jun. 30, 2018	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 19,600,000
Least amount of annual increase of shares available for issuance	386,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 70 days
Unrecognized expense from restricted stock units	$ 500,000
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 years 295 days
Equity Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	750,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	585,000
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	401,932	193,000
Percentage shares available for issuance automatically increase annually	1.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	208,932
2011 Stock Option Issuance Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			4,714,982
2018 Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		1,822,000
Percentage shares available for issuance automatically increase annually	4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	835,728
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	840,000

Note 10. Fair Value Measurement Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	$ 61,984		$ 45,716
Cash and cash equivalents	61,984	$ 58,110	45,716	$ 42,045
Short-term Investments	85,687		66,917
Warrants liabilities	295		860
Exercise of warrants	(13)
Change in fair market value of warrants	(552)	82
Term A Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair market value of warrants	(274)	$ 37
Term B Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair market value of warrants	(206)
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	61,984		45,716
Short-term Investments	21,146		39,920
Warrants liabilities	0		0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0		0
Short-term Investments	64,541		26,997
Warrants liabilities	0		0
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market funds	0		0
Short-term Investments	0		0
Warrants liabilities	295		860
U.S. government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	10,593		38,737
U.S. government securities \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	10,593		38,737
U.S. government securities \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
U.S. government securities \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Corporate Debt Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	53,178		15,066
Corporate Debt Securities \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Corporate Debt Securities \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	53,178		15,066
Corporate Debt Securities \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Agency Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	11,363		11,931
Agency Securities \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Agency Securities \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	11,363		11,931
Agency Securities \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Commercial Paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	10,553		1,183
Commercial Paper \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	10,553		1,183
Commercial Paper \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	0		0
Commercial Paper \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term Investments	$ 0		$ 0

Note 11. Short-Term Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Available For Sale Securities Maturities Period	132 days
Available-for-sale securities, Amortized Cost	$ 85,636
Gross, unrealized gains on short-term investments	51	$ 0
Short-term Investments	85,687		$ 66,917
Agency Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	11,350
Gross, unrealized gains on short-term investments	13
Short-term Investments	11,363		11,931
Commercial Paper
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	10,553
Gross, unrealized gains on short-term investments	0
Short-term Investments	10,553		1,183
Corporate Debt Securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	53,155
Gross, unrealized gains on short-term investments	23
Short-term Investments	53,178		15,066
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale securities, Amortized Cost	10,578
Gross, unrealized gains on short-term investments	15
Short-term Investments	$ 10,593		$ 38,737

Label	Element	Value
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue	$ 13,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue	$ 5.18
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	$ 600,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	4 years
Non--employee stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	2 years