XML 35 R19.htm IDEA: XBRL DOCUMENT v3.22.4
Stockholders' Equity
 12 Months Ended
Dec. 31, 2022
Stockholders' Equity Note [Abstract]  
Stockholders' Equity Stockholders’ Equity
Preferred Stock
   Shares Outstanding as of
December 31,
 Shares AuthorizedShares Issued20222021
Series C Preferred Stock, par $0.001
1,091 1,091 9 9 

The holder of a share or shares of Series C preferred stock has the right at any time, at such holder’s option, to convert all or any lesser portion of such holder’s shares of the preferred stock into fully paid and non-assessable shares of common stock. As of December 31, 2021, the conversion value was $27.20 per share, such that the outstanding shares of Series C preferred stock were convertible into an aggregate of 3,309 shares of common stock.
Issuances of Common Stock
On November 9, 2021, the Company entered into an ATM Equity OfferingSM Sales Agreement (the “2021 Sales Agreement”) with outside sales agents (collectively, the “Sales Agents”) for the offer and sale of its common stock for an aggregate offering price of up to $300.0 million. The 2021 Sales Agreement provides that the Sales Agents will be entitled to compensation in an amount equal to up to 3.0% of the gross sales proceeds of any common stock sold through the Sales Agents under the 2021 Sales Agreement. During the years ended December 31, 2022 and 2021, the Company sold 34,445,743 and 6,955,341 shares, respectively, of its common stock under the 2021 Sales Agreement. The sales were made at a weighted average price of $2.44 and $6.96 per share, respectively, resulting in aggregate net proceeds of $83.0 million and $47.7 million, respectively. As of December 31, 2022 there was $167.4 million of remaining capacity under the 2021 Sales Agreement.
On January 25, 2021, the Company closed an underwritten public offering of 20,355,000 shares of common stock at a public offering price of $8.50 per share. The net proceeds to the Company, after deducting the underwriters' discounts and commissions and other offering expenses, were $162.1 million.
Stock Options and Restricted Stock Units
The Company has a stock-based incentive plan, the 2016 Omnibus Incentive Plan (as amended to date, the "2016 Incentive Plan"), pursuant to which the Company may grant stock options, restricted stock awards, RSUs and other stock-based awards or short-term cash incentive awards to employees, directors and consultants.
The 2016 Incentive Plan was originally approved by the Company's stockholders on May 13, 2016, and an amendment to the plan to increase the number of shares available for issuance was approved by the stockholders on May 8, 2019. As of December 31, 2022, the maximum number of shares of the Company’s common stock available for issuance over the term of the 2016 Incentive Plan was 22,000,000 shares. On the first business day of each calendar year, the maximum number of shares is increased by 2,000,000 shares of common stock unless the Company's board of directors determines, prior to January 1 for any such calendar year, to increase the maximum amount by a lesser amount. On January 1, 2022 and again on January 1, 2023, the maximum number of shares increased by 2,000,000. At December 31, 2022, the Company had 3,831,240 shares of common stock available for future grant under the 2016 Incentive Plan, 2,446,257 shares underlying outstanding but unvested service-based RSUs, options outstanding to purchase 10,132,969 shares of common stock and 111,941 shares of performance-based RSUs outstanding under the 2016 Incentive Plan. The awards granted and available for future grant under the 2016 Incentive
Plan generally vest over three years and have a maximum contractual term of ten years. The 2016 Incentive Plan terminates by its terms on March 9, 2026.
On June 24, 2022, the Company's board of directors adopted a stock-based incentive plan (the "2022 Inducement Plan"), which provides for the discretionary grant of nonstatutory stock options, stock appreciation rights, restricted stock awards, RSU awards, performance awards, and other awards to individuals as a material inducement to entering into employment with the Company. The aggregate number of shares of the Company’s common stock that may be issued under the 2022 Inducement Plan will not exceed 2,000,000 shares. At December 31, 2022 the Company had 1,703,750 shares of common stock available for future grant under the 2022 Inducement Plan, 110,000 shares underlying outstanding but unvested RSUs and options outstanding to purchase 186,250 shares of common stock under the 2022 Inducement Plan. The 2022 Inducement Plan can be terminated by the Company's board of directors at any time.
The Amended and Restated 2007 Omnibus Incentive Plan (the "2007 Incentive Plan") was adopted on March 31, 2007 and terminated by its terms on March 31, 2017. At December 31, 2022, the Company had options outstanding to purchase 1,902,329 shares of common stock under the 2007 Incentive Plan. The awards granted under the 2007 Incentive Plan generally vest over three years and have a maximum contractual term of ten years.
Total employee and director stock-based compensation expense recognized in the consolidated statements of operations for the years ended December 31, 2022, 2021 and 2020 was $22.2 million, $25.0 million and $14.5 million, respectively, of which $8.8 million, $13.4 million and $8.0 million was included in research and development expenses and $13.4 million, $11.6 million and $6.5 million was included in general and administrative expenses, respectively. The Company entered into a Separation Agreement with its former President and Chief Executive Officer on May 10, 2022, under which outstanding RSUs as of the separation date were fully vested, and one-half of the RSUs were settled in the Company's common stock and the remainder settled in cash. The officer's stock options will continue to vest over a certain period and will remain exercisable until five years after the separation date. Stock-based compensation for the year ended December 31, 2022 included a $4.2 million charge related to these RSU and stock option modifications.
At December 31, 2022 and 2021, there was $10.5 million and $16.5 million, respectively, of total unrecognized compensation expense related to unvested stock options, which is expected to be recognized over a weighted-average period of 1.6 years and 2.0 years, respectively.
At December 31, 2022 and 2021, there was $7.2 million and $13.4 million, respectively, of total unrecognized compensation expense related to unvested RSUs, which is expected to be recognized over a weighted-average period of 1.7 years and 1.8 years, respectively.
The fair value of stock options granted to non-employees was estimated using the Black-Scholes pricing model. Total stock-based compensation expense for stock options and RSUs granted to non-employees for the years ended December 31, 2022, 2021 and 2020 was $1.3 million, $1.4 million and $1.2 million, respectively. As of December 31, 2022, options to purchase 665,875 shares of common stock granted to non-employees remained outstanding.
The following table summarizes total stock options outstanding at December 31, 2022:
 
 Options OutstandingOptions Exercisable
Exercise PriceShares Underlying Options
Outstanding		Weighted-Average
Remaining
Contractual Life
(in Years)		Weighted
Average
Exercise Price		Shares Underlying Options
Exercisable		Weighted Average
Exercise Price
$1.56-$3.00
830,542 8.3$2.17 247,104 $2.29 
$3.01-$6.00
5,461,365 7.1$3.50 3,059,330 $3.67 
$6.01-$9.00
3,349,587 5.3$7.57 2,861,909 $7.49 
$9.01-$12.00
1,930,825 7.1$10.97 1,080,389 $10.89 
$12.01-$15.00
580,947 4.1$13.38 529,392 $13.34 
$15.01-$25.62
68,282 7.6$21.12 51,568 $21.11 
12,221,548 6.6$6.28 7,829,692 $6.79 

At December 31, 2022, the aggregate intrinsic value of options outstanding was $0, the aggregate intrinsic value of options exercisable was $0, and the weighted average remaining contractual term of options exercisable was 5.7 years.
At December 31, 2022, the aggregate intrinsic value of unvested RSUs was $4.0 million and the aggregate intrinsic value of RSUs which vested during the year ended December 31, 2022 was $4.6 million.
At December 31, 2022, options to purchase 12,221,548 shares of common stock and 2,556,257 RSUs were expected to vest.
Stock option activity under the Company’s equity incentive plans during the year ended December 31, 2022 was as follows:
Number of
Shares		Weighted-Average
Exercise Price
Balance, December 31, 202110,488,993 $7.93 
Granted4,623,448 3.11 
Exercised(118,694)2.38 
Cancelled(2,772,199)7.46 
Balance, December 31, 202212,221,548 $6.28 

Restricted stock unit activity under the Company’s equity incentive plans during the year ended December 31, 2022 was as follows:
Number of
Shares
Balance, December 31, 20212,448,868 
Granted2,485,947 
Vested(1,618,235)
Cancelled(760,323)
Balance, December 31, 20222,556,257 

The weighted average exercise price per share was $8.47 for the 77,250 options which expired during the year ended December 31, 2022, $4.56 for the 7,000 options which expired during the year ended December 31, 2021 and $4.44 for the 78,750 options which expired during the year ended December 31, 2020.
The weighted average grant date fair value per share was $2.34, $7.61 and $6.87 for options granted during the years ended December 31, 2022, 2021 and 2020, respectively.
The weighted average grant date fair value was $3.12, $10.37 and $9.12 per share for RSUs granted during the years ended December 31, 2022, 2021 and 2020, respectively.
The Company received $283,000, $6.7 million and $12.3 million in proceeds from the exercise of stock options during the years ended December 31, 2022, 2021 and 2020, respectively. The aggregate intrinsic value of options exercised was $81,000, $7.0 million and $14.2 million during the years ended December 31, 2022, 2021 and 2020, respectively.
As of December 31, 2022, the Company had 111,941 performance-based RSUs outstanding, which were granted to key employees in August 2020. The underlying performance milestones of the RSUs were not probable of achievement as of December 31, 2022, and no stock-based compensation expense has been recognized to date for the performance-based RSUs.