14. Stock-Based Compensation

2019 Inducement Plan

In October 2019, the Company’s Board of Directors adopted the 2019 Inducement Plan, or the 2019 Plan, which is a non-stockholder approved stock plan adopted pursuant to the “inducement exception” provided under Nasdaq Listing Rule 5635(c)(4), or Rule 5635, for the purpose of awarding (i) non-statutory stock options, (ii) restricted stock awards, (iii) restricted stock unit awards, (iv) other stock awards (collectively, the Inducement Awards) to new employees of the Company, as inducement material to such new employees entering into employment with the Company. In November 2019, the Company filed a Registration Statement on Form S-8 with the SEC covering the offering of up to 300,000 shares of its common stock, par value $0.001, pursuant to the Company’s 2019 Plan. Initial grants of Inducement Awards made to employees vest as to 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months and subsequent grants vest monthly over a period of four years from the grant date.

2014 Equity Incentive Plan

The Company’s 2014 Equity Incentive Plan, or the 2014 Plan, is administered by the Company’s Board of Directors or a duly authorized committee thereof, referred to as the Plan administrator. The 2014 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards, stock appreciation rights, performance stock awards and other forms of equity compensation, collectively referred to as Stock Awards. Additionally, the 2014 Plan provides for the grant of performance cash awards. Incentive stock options may be granted only to employees. All other awards may be granted to employees, including officers, non-employee directors, and consultants. No incentive stock options may be granted under the 2014 Plan after the tenth anniversary of the effective date of the 2014 Plan. Stock Awards granted under the 2014 Plan vest at the rate specified by the Plan administrator. Initial grants of Stock Awards made to employees and non-employee consultants generally vest as to 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months and subsequent grants vest monthly over a period of four years from the grant date. Stock options initially granted to members of the Company’s Board of Directors generally vest over a period of three years in equal quarterly installments from the date of the grant, subject to the option holder’s continued service as a director through such date. Subsequent grants to directors that are made automatically at Annual Meetings of Stockholders vest fully on the earlier of the first anniversary of the date of grant and the next Annual Meeting of Stockholders. The Plan administrator determines the term of Stock Awards granted under the 2014 Plan up to a maximum of ten years.

The aggregate number of shares of the Company’s common stock reserved for issuance under the 2014 Plan has automatically increased on January 1 of each year, beginning on January 1, 2015 and will continue to increase on January 1 of each year through and including January 1, 2024, by 3% of the total number of shares of the Company’s capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s Board of Directors. On January 1, 2023, the aggregate number of shares of common stock that may be issued pursuant to Stock Awards under the 2014 Plan automatically increased from 10,589,103 to 12,203,023. The

maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2014 Plan is 30,000,000 shares.

Restricted Stock Units

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 194,172 restricted stock units were granted to non-employee directors on June 1, 2023, the date of the Company’s 2023 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $3.09 per share. The restricted stock units will vest on the earlier of (i) June 1, 2024 and (ii) immediately prior to the Company’s next Annual Meeting of Stockholders following the grant date, subject to the recipient’s continued service through such date. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For each of the three and six months ended June 30, 2023, stock compensation expense associated with these awards of $49 was recognized in general and administrative expense, or G&A expense. As of June 30, 2023, 194,172 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On March 1, 2023, the Compensation Committee of the Company’s Board of Directors, or the Compensation Committee, approved and granted a total of 407,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.06 per share. Vesting of the restricted stock units is contingent on the achievement of certain performance targets, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria are probable of achievement and the employee has met the service conditions. For each of the three and six months ended June 30, 2023, no stock compensation expense relating to these restricted stock units was recognized. As of June 30, 2023, 407,000 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On October 12, 2022, the Compensation Committee approved and granted a total of 7,267 time-based restricted stock units under the 2014 Plan, with a grant date fair value of $9.42 per share, to an executive officer of the Company. The restricted stock unit grant fully vests on August 31, 2023, subject to the recipient’s continued service through such date. For the three and six months ended June 30, 2023, the Company recognized $19 and $38, respectively, of stock compensation expense associated with these awards, all of which was recorded within G&A expense. As of June 30, 2023, 7,267 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On June 15, 2022, the Compensation Committee approved and granted a total of 7,500 time-based restricted stock units to the Company’s interim principal financial officer and principal accounting officer, as a result of his assuming the responsibilities of the Company’s former Chief Financial Officer on an interim basis, under the 2014 Plan with a grant date fair value of $7.94 per share. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the vesting period following the grant date. For each of the three and six months ended June 30, 2022, the Company recognized $5 of stock compensation expense associated with these awards, all of which were recorded within G&A expense. As of June 30, 2023, none of these restricted stock units were outstanding as these restricted stock units vested fully in September 2022.

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 59,380 restricted stock units were granted to non-employee directors on June 2, 2022, the date of the Company’s 2022 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $8.42 per share. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For the three and six months ended June 30, 2023, stock compensation expense associated with these awards

of $86 and $209, respectively, was recognized in G&A expense. For each of the three and six months ended June 30, 2022, stock compensation expense of $38 was recognized in G&A expense. As of June 30, 2023, none of these restricted stock units were outstanding as these restricted stock units vested fully on June 2, 2023. Also in June 2022, the Company granted 11,876 fully vested restricted stock units, which were immediately settled in shares of common stock, to the Company’s chairman in consideration of his effort in connection with the Company’s CEO transition in 2021. For each of the three and six months ended June 30, 2022, stock compensation expense of $100 was recognized in G&A expense associated with this award.

On February 25, 2022, the Compensation Committee also approved and granted a total of 243,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.46 per share. Vesting of the restricted stock units is contingent on the achievement of certain performance targets related to commercial milestones, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria are probable of achievement and the employee has met the service conditions. For each of the three and six months ended June 30, 2023 and 2022, no stock compensation expense relating to these restricted stock units was recognized. In June 2022, 29,000 of these restricted stock units were forfeited as a result of the resignation of our former CFO. In December 2022, 214,000 of these restricted stock units were cancelled as the performance targets associated with them were not achieved. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units were cancelled in 2022.

Additionally, on February 25, 2022, the Compensation Committee also approved and granted a total of 145,170 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.46 per share. The restricted stock units vest in three equal installments annually from the date of the grant. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the three-year vesting period following the grant date. In April 2023, 3,585 of these restricted stock units were forfeited. In February 2023, 42,920 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the first year of vesting. For the three and six months ended June 30, 2023, the Company recognized $85 and $199, respectively, of stock compensation expense associated with these awards, with $17 recorded in R&D expense and $68 recorded in G&A expense for the three months ended June 30, 2023, and $64 recorded in R&D expense and $135 recorded in G&A expense for the six months ended June 30, 2023. For the three and six months ended June 30, 2022, the Company recognized $108 and $158, respectively, of stock compensation expense associated with these awards, with $47 recorded in R&D expense and $61 recorded in G&A expense for the three months ended June 30, 2022, and $65 recorded in R&D expense and $93 recorded in G&A expense for the six months ended June 30, 2022. During the three months ended June 30, 2022, 20,000 of these restricted stock units were forfeited as a result of the resignation of the Company’s former CFO in June 2022. As of June 30, 2023, 78,665 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On December 17, 2021, the Compensation Committee approved and granted a total of 63,573 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $12.45 per share. The restricted stock units vested in two equal installments on December 15, 2022 and June 15, 2023. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the 18-month vesting period following the grant date. On June 15, 2023, the remaining 26,199 of these restricted stock units fully vested and were settled in shares of the Company’s common stock. For the three and six months ended June 30, 2023, the Company recognized $91 and $199, respectively, of stock compensation expense associated with these awards, with $44 recorded in R&D expense and $47 recorded in G&A expense for the three months ended June 30, 2023, and $96 recorded in R&D expense and $103 recorded in G&A expense for the six months ended June 30, 2023. In June 2022, 11,170 of these restricted stock units were forfeited as a result of the resignation of the Company’s former CFO. For the three and six months ended June 30, 2022, the Company recognized $82 and $213, respectively, of stock compensation expense associated with these awards,

with $52 recorded in R&D expense and $30 recorded in G&A expense for the three months ended June 30, 2022, and $104 recorded in R&D expense and $109 recorded in G&A expense for the six months ended June 30, 2022. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units fully vested in June 2023.

On October 29, 2021, the Compensation Committee also approved and granted 147,942 time-based restricted stock units in connection with the appointment of the Company’s new CEO under the 2014 Plan with a grant date fair value of $16.83 per share. The first tranche of 142,000 restricted stock units vested 25% on the first anniversary of the date of grant and the balance vests quarterly over the next 36 months. As a result, 35,500 of these restricted stock units vested and were settled in shares of the Company’s common stock in October 2022. The second tranche of 5,942 restricted stock units fully vested on March 31, 2022. As a result, the Company recognizes compensation expense associated with these two restricted stock unit tranches ratably over their respective vesting periods following the grant date. In April 2023 and January 2023, 8,875 of these restricted stock units vested each period and were settled in shares of the Company’s common stock in satisfaction of the quarterly periods of vesting. For the three and six months ended June 30, 2023, stock compensation expense associated with these awards of $149 and $296, respectively, was recognized in G&A expense. For the three and six months ended June 30, 2022, stock compensation expense associated with these awards of $149 and $355, respectively, was recognized in G&A expense. As of June 30, 2023, 88,750 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 43,200 restricted stock units were granted to non-employee directors on June 3, 2021, the date of the Company’s 2021 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $13.06 per share. The restricted stock units vested on June 3, 2022. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For the three and six months ended June 30, 2022, stock compensation expense associated with these awards of $100 and $239, respectively, was recognized in G&A expense for these restricted stock units. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units fully vested in June 2022.

On March 30, 2021, the Compensation Committee approved and granted a total of 176,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $20.59 per share. Vesting of the restricted stock units was contingent on the achievement of certain performance targets related to clinical and regulatory milestones, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria is probable of achievement and the employee has met the service conditions. In March 2022, 93,999 restricted stock units were forfeited as a result of not achieving certain defined performance targets of the awards. In February 2022, performance targets relating to 37,999 restricted stock units had been achieved and thus restricted stock units vested and the awards were settled in shares of common stock. For each of the three and six months ended June 30, 2023, there was no stock compensation expense recognized as all of these restricted stock units either vested or were forfeited prior to these periods. For the six months ended June 30, 2022, the Company recognized $729 of stock compensation expense associated with these awards in G&A expense. G&A amounts recorded for the six months ended June 30, 2022 included $303 of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units either fully vested or were forfeited in prior periods.

Additionally on March 30, 2021, the Compensation Committee also approved and granted a total of 100,000 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $20.59 per share. The restricted stock units vest in three equal installments annually from the date of the grant. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the three-year vesting period

following the grant date. In March 2023, 15,999 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the second year of vesting. In June 2022, 17,333 of these restricted stock units vested and were settled in shares of the Company’s common stock in accordance with the acceleration of vesting provisions relating to the modification of certain of these restricted stock units on November 1, 2021. In June 2022, 17,333 restricted stock units were forfeited as a result of the completion of the consulting agreement in relation to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). In March 2022, 33,336 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the first year of vesting. For the three and six months ended June 30, 2023, the Company recognized $82 and $163, respectively, of stock compensation expense associated with these awards, with $55 recorded in R&D expense and $27 in G&A expense for the three months ended June 30, 2023, and $109 recorded in R&D expense and $54 in G&A expense for the six months ended June 30, 2023. For the three and six months ended June 30, 2022, the Company recognized $196 and $480, respectively, of stock compensation expense associated with these awards, with $55 recorded in R&D expense and $141 in G&A expense for the three months ended June 30, 2022, and $109 recorded in R&D expense and $371 in G&A expense for the six months ended June 30, 2022. G&A amounts recorded for the three and six months ended June 30, 2022 included $114 and $317, respectively, of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, 15,999 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

In February 2020, the Compensation Committee also approved and granted a total of 98,000 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $16.36 per share. The restricted stock units vested in three equal installments annually from the date of the grant. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the three-year vesting period following the grant date. In February 2023, 15,999 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the third year of vesting. In February 2022, 32,666 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the second year of vesting. For the six months ended June 30, 2023, the Company recognized $39 of stock compensation expense associated with these awards, with $26 recorded in R&D expense and $13 in G&A expense. There was no associated stock compensation expense for the three months ended June 30, 2023 as these restricted stock units were fully vested in the prior period. For the three and six months ended June 30, 2022, the Company recognized $175 and $394, respectively, of stock compensation expense associated with these awards, with $44 recorded in R&D expense and $131 in G&A expense for the three months ended June 30, 2022, and $87 recorded in R&D expense and $307 in G&A expense for the six months ended June 30, 2022. G&A amounts recorded for the three and six months ended June 30, 2022 included $109 and $264, respectively, of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units were fully vested in February 2023.

A summary of restricted stock unit activity related to employees and non-employee members of the Company’s Board of Directors as of and for the six months ended June 30, 2023 is presented below:

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Stock Options

Under the 2014 Plan, the Company granted 349,767 and 324,981 stock options during the three months ended June 30, 2023 and 2022, respectively, and 1,798,921 and 1,302,419 stock options during the six months ended June 30, 2023 and 2022, respectively. No stock options were granted under the 2019 Inducement Plan during the three and six months ended June 30, 2023 and 2022. The fair values of stock options granted during the three and six months ended June 30, 2023 and 2022 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions:

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The weighted-average grant date fair value per share of options granted to employees and non-employee members of the Company’s Board of Directors for their Board service during the three months ended June 30, 2023 and 2022 was $2.43 and $6.30, respectively, and during the six months ended June 30, 2023 and 2022 was $6.18 and $7.23, respectively. No options were granted to non-employee consultants during the three and six months ended June 30, 2023 and 2022.

During the three and six months ended June 30, 2023 and 2022, the Company recognized compensation expense relating to stock options as follows:

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The following were excluded from the table above as they are not related to stock options: compensation expense for (i) the vesting of certain employees’ restricted stock units for $116 in R&D expense and $310 in G&A expense for the three months ended June 30, 2023, and $295 in R&D expense and $639 in G&A expense for the six months ended June 30, 2023; (ii) the vesting of certain employees’ restricted stock units for $198 in R&D expense and $517 in G&A expense for the three months ended June 30, 2022, and $365 in R&D expense and $1,969 in G&A expense for the six months ended June 30, 2022; (iii) compensation expense relating to the Board of Directors’ restricted stock units for $135 and $258 in G&A expense for the three and six months ended June 30, 2023, respectively; and (iv) compensation expense relating to the Board of Directors’ restricted stock units for $238 and $377 in G&A expense for the three and six months ended June 30, 2022, respectively.

A summary of stock option award activity related to employees, non-employee members of the Company’s Board of Directors and non-employee consultants as of and for the six months ended June 30, 2023 is presented below:

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The Company does not expect to realize any tax benefits from its stock option activity or the recognition of stock-based compensation expense because the Company currently has net operating losses and has a full valuation allowance against its deferred tax assets. Accordingly, no amounts related to excess tax benefits have been reported in cash flows from operations for the six months ended June 30, 2023 and 2022.

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Stock Award Modifications

In November 2021, the Company and the former President and CEO mutually agreed to a transition from CEO to a consulting role through June 30, 2022, if not terminated earlier per the terms of the consulting agreement. As a result, the Company modified the terms of its former CEO’s outstanding Stock Awards to (1) automatically vest any unvested stock options or time-based restricted stock units that would have vested in the twelve month period following the end of the consulting period if continuous service is achieved with the Company during such twelve-month period; (2) extend the period during which the vested stock options may be exercised through the earlier of (i) eighteen months following the separation date (November 8, 2021); or (ii) the original expiration date applicable to each of the stock options, unless terminated earlier in accordance with the 2014 Plan, if continuous service is achieved with the Company; and (3) extend the period in which performance-based vesting milestones for restricted stock units may be achieved through March 31, 2022, if continuous service is achieved with the Company. The consulting agreement ended on June 30, 2022.

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The Company determined that vested Stock Awards which had modifications due to the extension of the exercise period were Type 1 modifications pursuant to Financial Accounting Standards Board Accounting Standards Codification 718, or ASC 718, because those Stock Awards would have vested before and after the modification. Acceleration of vesting for the Stock Awards that would have vested in the twelve-month period following the consulting term was determined to be a Type 3 modification requiring stock compensation expense pursuant to ASC 718 because absent the modification terms, those Stock Awards would have been forfeited as of the last day that the former CEO provided

continuous service as a consultant. In addition, Type 4 performance-based restricted stock units were not considered probable of achieving performance targets on the modification date, but the vesting targets were achieved with respect to 17,333 performance-based restricted stock units in February 2022, which resulted in additional stock compensation expense being recorded during the six months ended June 30, 2022.

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During the three and six months ended June 30, 2022, total incremental stock compensation expense relating to modifications of stock options, time-based and performance-based restricted stock units of the former CEO was $999 and $2,563, respectively, which was included in G&A expense for the three and six months ended June 30, 2022, respectively. Of this total amount, $776 and $1,679 were included in G&A expense in the stock option compensation expense table above for the three and six months ended June 30, 2022, respectively.