March 31,
2024

December 31,
2023

Stock options issued and outstanding

11,859,362

9,208,970

Stock options reserved for 2020 Incentive Award Plan

1,762,992

1,988,340

Unvested restricted stock units outstanding

915,861

495,579

Common stock reserved for 2021 ATM program

25,980,123

2,619,471

Common stock reserved for 2024 ATM program

25,000,000

—

Common stock reserved for Employee Stock Purchase
     Plan

2,122,071

1,338,381

Common stock reserved for 2022 Employment Inducement 
    Award Plan

1,667,300

758,084

Common stock reserved for pre-funded warrants

35,248,479

40,493,510

Common stock reserved for common warrants

8,427,508

8,427,508

Total common stock reserved

112,983,696

65,329,843