v3.26.1
Stockholders’ Equity and Stock-Based Compensation
 6 Months Ended
Jun. 30, 2026
Share-Based Payment Arrangement [Abstract]  
Stockholders’ Equity and Stock-Based Compensation

6. Stockholders’ Equity and Stock-Based Compensation

Sale of Common Stock

Cowen At-the-Market Facility

On March 23, 2021, the Company entered into a Sales Agreement with Cowen and Company, LLC (“Cowen”) which provides for the sale, in the Company’s sole discretion, of shares of common stock having an aggregate offering price of up to $350.0 million through or to Cowen, acting as sales agent or principal, which was amended on March 9, 2023 to decrease the maximum aggregate offering price to $200.0 million for sales made on and after the date of the amendment (the “Cowen ATM”). The Company agreed to pay Cowen a commission of up to 3.0% of the aggregate gross proceeds from each sale of shares, reimburse legal fees and disbursements and provide Cowen with customary indemnification and contribution rights. On February 4, 2025, the Company provided notice of its termination, effective February 14, 2025, of the Cowen ATM.

Wainwright At-the-Market Facility

On February 21, 2025, the Company entered into an At The Market Offering Agreement (the “ATM Agreement”) with H.C. Wainwright & Co., LLC (“Wainwright”), pursuant to which the Company may offer and sell, from time to time at its sole discretion, shares of its common stock having an aggregate offering price of up to $75.0 million, through or to Wainwright, acting as sales agent or principal. The Company agreed to pay Wainwright a commission of up to 3.0% of the aggregate gross proceeds from each sale of shares, reimburse

legal fees and disbursements and provide Wainwright with customary indemnification and contribution rights. During the six months ended June 30, 2026, the Company sold approximately 1.0 million shares of common stock under the ATM Agreement at an average share price of $1.28 per share, and received gross proceeds of approximately $1.3 million before deducting offering costs of $0.05 million.

Stock Warrants

A summary of the Company’s warrant activity during the six months ended June 30, 2026 was as follows:

 

 

Shares of
Stock under
Warrants

 

 

Weighted-
Average
Exercise
Price

 

 

Weighted-
Average
Remaining
Contractual
Term

 

 

Aggregate Intrinsic Value (in thousands)

 

Outstanding at January 1, 2026

 

 

12,080,500

 

 

$

13.22

 

 

 

2.87

 

 

$

—

 

Granted

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Exercised

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Canceled

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Outstanding at June 30, 2026

 

 

12,080,500

 

 

$

13.22

 

 

 

2.40

 

 

$

—

 

Stock Options

A summary of the Company’s stock option activity during the six months ended June 30, 2026 was as follows:

 

 

Shares of
Stock under
Stock Options

 

 

Weighted-
Average
Exercise
Price

 

 

Weighted-
Average
Remaining
Contractual
Term

 

 

Aggregate Intrinsic Value (in thousands)

 

Outstanding at January 1, 2026

 

 

190,000

 

 

$

237.26

 

 

 

8.71

 

 

$

—

 

Granted

 

 

493,000

 

 

 

1.26

 

 

 

—

 

 

 

—

 

Exercised

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Canceled

 

 

(67,000

)

 

 

10.02

 

 

 

—

 

 

 

—

 

Outstanding and expected to vest at June 30, 2026

 

 

616,000

 

 

 

71.66

 

 

 

7.82

 

 

 

12.00

 

Vested and exercisable at June 30, 2026

 

 

186,000

 

 

$

228.01

 

 

 

5.63

 

 

$

—

 

 

For the three and six months ended June 30, 2026, the weighted-average grant date fair value of stock options granted was $0.90 and $1.04 per share, respectively.

Stock-Based Compensation

The Company recognized stock-based compensation expense for the periods presented as follows (in thousands):

 

 

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

 

2026

 

 

2025

 

 

2026

 

 

2025

 

Cost of product revenue

 

$

27

 

 

$

40

 

 

$

58

 

 

$

77

 

Cost of service and other revenue

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Research and development

 

 

71

 

 

 

160

 

 

 

149

 

 

 

410

 

General and administrative

 

 

872

 

 

 

880

 

 

 

1,433

 

 

 

2,180

 

Total stock-based compensation expense

 

$

970

 

 

$

1,080

 

 

$

1,640

 

 

$

2,667

 

 

 

The weighted-average assumptions used in the Black-Scholes-Merton option pricing model to determine the fair value of the employee stock option grants during the periods presented were as follows:

 

 

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

 

2026

 

 

2025

 

 

2026

 

 

2025

 

Risk-free interest rate

 

 

4.1

%

 

 

4.0

%

 

 

3.9

%

 

 

4.1

%

Expected volatility

 

 

94.2

%

 

 

119.3

%

 

 

108.1

%

 

 

135.0

%

Expected term (in years)

 

 

5.3

 

 

 

5.5

 

 

 

5.7

 

 

 

5.6

 

Expected dividend yield

 

 

0.0

%

 

 

0.0

%

 

 

0.0

%

 

 

0.0

%

Restricted Stock Units

The following table summarizes RSU activity during the six months ended June 30, 2026:

 

 

Stock Units

 

 

Weighted- Average
Grant Date Fair
Value per Share

 

Outstanding at January 1, 2026

 

 

3,490

 

 

$

290.34

 

Granted

 

 

—

 

 

 

—

 

Released

 

 

(1,490

)

 

 

356.64

 

Forfeited

 

 

(260

)

 

 

63.31

 

Outstanding at June 30, 2026

 

 

1,740

 

 

$

265.28

 

 

The total fair value of the RSUs that vested during the six months ended June 30, 2026 was $0.5 million, determined as of the date of vesting. The weighted average remaining contractual term for the RSUs was 1.7 years as of June 30, 2026.

Executive Option Grants

On February 2, 2026, the compensation committee of the Company’s board of directors granted various executive officers stock options to purchase an aggregate of approximately 0.2 million shares of common stock at an exercise price of $1.27 per share, with an effective grant date and vesting commencement date of February 2, 2026.

These stock option grants were issued from the 2018 Plan. The shares subject to the stock options shall vest monthly over 48 months beginning on the one-month anniversary of their respective grant dates, such that the stock options shall be fully vested and exercisable on the four-year anniversary of their respective grant dates.