6.    Stockholders’ Equity

Our common stock outstanding as of September 30, 2020 and December 31, 2019 was 116,763,180 shares and 57,378,794 shares, respectively.

January 2020 Offering

In January 2020, we completed a financing with several institutional investors pursuant to which we issued 8,700,000 shares of our common stock in a registered direct offering and warrants to purchase 8,700,000 shares of our common stock with an exercise price of $0.25 per share in a concurrent private placement (the “January 2020 Warrants") pursuant to which we received net cash proceeds of approximately $1.9 million, after deduction of underwriting fees and other offering expenses. The January 2020 Warrants became exercisable in September 2020 following receipt of stockholder approval of an increase in our authorized shares of common stock and they expire in July 2025. During the three months ended March 31, 2020, financing costs of $211,000 allocated to the January 2020 warrant liability were expensed and included in other income (expense) in the condensed statements of operations and comprehensive loss.

September 2020 Offering

In September 2020, we completed a registered direct offering with several institutional investors pursuant to which we issued 19,440,000 shares of our common stock at a price of $0.14 per share. We received net cash proceeds of approximately $2.4 million, after deduction of underwriting fees and other offering expenses.

Common Stock Warrants

During the nine months ended September 30, 2020, we received an aggregate of approximately $7.0 million in cash proceeds from the exercises of warrants to purchase 31,244,386 shares of our common stock.