SUBSEQUENT EVENTS	3 Months Ended
Mar. 31, 2020
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	7. SUBSEQUENT EVENTS At Market Issuance Sales Agreement On July 10, 2018, we filed a prospectus supplement, or the ATM Prospectus Supplement, pursuant to which we may offer and sell, from time to time, shares of our common stock having an aggregate offering price of up to $62,821,700 under the 2018 Sales Agreement. In the second quarter of 2020, we sold an aggregate of 2,966,388 shares of our common stock pursuant to the 2018 Sales Agreement, resulting in net cash proceeds to us of approximately $3,391,000 after deducting sales commissions and estimated offering expenses payable by us. In connection with the public offering in May 2020 described below, we have terminated the ATM Prospectus Supplement, but the 2018 Sales Agreement remains in full force and effect. We cannot make any sales of common stock under the 2018 Sales Agreement for 90 days after completion of our public offering and unless and until we file an updated prospectus supplement. For further discussion of the 2018 Sales Agreement, see Note 6 on Stockholders’ Equity. Public Offering On May 27, 2020, we completed an underwritten public offering of 107,049,375 shares of our common stock and pre-funded warrants to purchase 8,335,239 shares of our common stock, also known as the pre-funded warrants, together with accompanying warrants to purchase 57,692,307 shares of our common stock, also known as the stock purchase warrants. The combined public offering price to the public of common stock and accompanying stock purchase warrants is $1.30 per share. The combined public offering price to the public of pre-funded warrants and accompanying stock purchase warrants is $1.299 per share. The estimated net cash proceeds from this offering, assuming no exercise of the pre-funded warrants or the stock purchase warrants, is approximately $140,200,000, after deducting the underwriting discount and estimated offering expenses payable by us.

SUBSEQUENT EVENTS

3 Months Ended

Mar. 31, 2020

7. SUBSEQUENT EVENTS

At Market Issuance Sales Agreement

On July 10, 2018, we filed a prospectus supplement, or the ATM Prospectus Supplement, pursuant to which we may offer and sell, from time to time, shares of our common stock having an aggregate offering price of up to $62,821,700 under the 2018 Sales Agreement. In the second quarter of 2020, we sold an aggregate of 2,966,388 shares of our common stock pursuant to the 2018 Sales Agreement, resulting in net cash proceeds to us of approximately $3,391,000 after deducting sales commissions and estimated offering expenses payable by us. In connection with the public offering in May 2020 described below, we have terminated the ATM Prospectus Supplement, but the 2018 Sales Agreement remains in full force and effect. We cannot make any sales of common stock under the 2018 Sales Agreement for 90 days after completion of our public offering and unless and until we file an updated prospectus supplement. For further discussion of the 2018 Sales Agreement, see Note 6 on Stockholders’ Equity.

Public Offering

On May 27, 2020, we completed an underwritten public offering of 107,049,375 shares of our common stock and pre-funded warrants to purchase 8,335,239 shares of our common stock, also known as the pre-funded warrants, together with accompanying warrants to purchase 57,692,307 shares of our common stock, also known as the stock purchase warrants. The combined public offering price to the public of common stock and accompanying stock purchase warrants is $1.30 per share. The combined public offering price to the public of pre-funded warrants and accompanying stock purchase warrants is $1.299 per share. The estimated net cash proceeds from this offering, assuming no exercise of the pre-funded warrants or the stock purchase warrants, is approximately $140,200,000, after deducting the underwriting discount and estimated offering expenses payable by us.