CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) | Total | Common Stock | Additional Paid-In Capital | Accumulated Other Comprehensive Loss | Accumulated Deficit |
Beginning Balance at Dec. 31, 2019 | $ 4,836,000 | $ 2,000 | $ 243,281,000 | | $ (238,447,000) |
Beginning Balance, shares at Dec. 31, 2019 | | 2,179,000 | | | |
Issuance of common stock for release of awards | (1,000) | | (1,000) | | |
Issuance of common stock for release of awards, shares | | 20,000 | | | |
Exercise of pre-funded warrants | 2,000 | | 2,000 | | |
Exercise of pre-funded warrants, shares | | 116,000 | | | |
Stock-based compensation | 68,000 | | 68,000 | | |
Net loss | (1,405,000) | | | | (1,405,000) |
Ending Balance at Mar. 31, 2020 | 3,500,000 | $ 2,000 | 243,350,000 | | (239,852,000) |
Ending Balance, shares at Mar. 31, 2020 | | 2,315,000 | | | |
Beginning Balance at Dec. 31, 2019 | 4,836,000 | $ 2,000 | 243,281,000 | | (238,447,000) |
Beginning Balance, shares at Dec. 31, 2019 | | 2,179,000 | | | |
Deemed dividend for warrant exercise price adjustment | 392,000 | | | | |
Net loss | (2,751,000) | | | | |
Ending Balance at Sep. 30, 2020 | 3,901,000 | $ 3,000 | 245,488,000 | | (241,590,000) |
Ending Balance, shares at Sep. 30, 2020 | | 3,553,000 | | | |
Beginning Balance at Mar. 31, 2020 | 3,500,000 | $ 2,000 | 243,350,000 | | (239,852,000) |
Beginning Balance, shares at Mar. 31, 2020 | | 2,315,000 | | | |
Issuance of common stock for release of awards, shares | | 1,000 | | | |
Sale of common stock, net of placement costs | 1,619,000 | $ 1,000 | 1,618,000 | | |
Sale of common stock, net of placement costs,shares | | 1,218,000 | | | |
Deemed dividend for warrant exercise price adjustment | | | 392,000 | | (392,000) |
Stock-based compensation | 66,000 | | 66,000 | | |
Net loss | (639,000) | | | | (639,000) |
Ending Balance at Jun. 30, 2020 | 4,546,000 | $ 3,000 | 245,426,000 | | (240,883,000) |
Ending Balance, shares at Jun. 30, 2020 | | 3,534,000 | | | |
Issuance of common stock for release of awards | (1,000) | | (1,000) | | |
Issuance of common stock for release of awards, shares | | 19,000 | | | |
Stock-based compensation | 63,000 | | 63,000 | | |
Net loss | (707,000) | | | | (707,000) |
Ending Balance at Sep. 30, 2020 | 3,901,000 | $ 3,000 | 245,488,000 | | (241,590,000) |
Ending Balance, shares at Sep. 30, 2020 | | 3,553,000 | | | |
Beginning Balance at Dec. 31, 2020 | $ 2,932,000 | $ 3,000 | 245,548,000 | | (242,619,000) |
Beginning Balance, shares at Dec. 31, 2020 | 3,554,000 | 3,554,000 | | | |
Issuance of common stock under stock plan, net | $ (2,000) | | (2,000) | | |
Issuance of common stock under stock plan, net, shares | | 16,000 | | | |
Exercise of warrants | 2,478,000 | $ 1,000 | 2,477,000 | | |
Exercise of warrants, shares | | 1,033,000 | | | |
Issuance of common stock for payment of accrued interest | 140,000 | | 140,000 | | |
Issuance of common stock for payment of accrued interest,shares | | 43,000 | | | |
Sale of common stock, net of placement costs | 6,817,000 | $ 2,000 | 6,815,000 | | |
Sale of common stock, net of placement costs,shares | | 1,488,000 | | | |
Stock-based compensation | 68,000 | | 68,000 | | |
Unrealized loss on available-for-sale investments | (1,000) | | | $ (1,000) | |
Net loss | (1,369,000) | | | | (1,369,000) |
Ending Balance at Mar. 31, 2021 | 11,063,000 | $ 6,000 | 255,046,000 | (1,000) | (243,988,000) |
Ending Balance, shares at Mar. 31, 2021 | | 6,134,000 | | | |
Beginning Balance at Dec. 31, 2020 | $ 2,932,000 | $ 3,000 | 245,548,000 | | (242,619,000) |
Beginning Balance, shares at Dec. 31, 2020 | 3,554,000 | 3,554,000 | | | |
Sale of common stock, net of placement costs | $ 139,964 | | | | |
Sale of common stock, net of placement costs,shares | 42,672 | | | | |
Unrealized loss on available-for-sale investments | $ (6,000) | | | | |
Net loss | (4,288,000) | | | | |
Ending Balance at Sep. 30, 2021 | $ 22,063,000 | $ 9,000 | 268,967,000 | (6,000) | (246,907,000) |
Ending Balance, shares at Sep. 30, 2021 | 8,686,000 | 8,686,000 | | | |
Beginning Balance at Mar. 31, 2021 | $ 11,063,000 | $ 6,000 | 255,046,000 | (1,000) | (243,988,000) |
Beginning Balance, shares at Mar. 31, 2021 | | 6,134,000 | | | |
Issuance of common stock under stock plan, net, shares | | 2,000 | | | |
Exercise of warrants | 1,696,000 | $ 1,000 | 1,695,000 | | |
Exercise of warrants, shares | | 706,000 | | | |
Sale of common stock, net of placement costs | 11,969,000 | $ 1,000 | 11,968,000 | | |
Sale of common stock, net of placement costs,shares | | 1,818,000 | | | |
Stock-based compensation | 97,000 | | 97,000 | | |
Unrealized loss on available-for-sale investments | (3,000) | | | (3,000) | |
Net loss | (1,205,000) | | | | (1,205,000) |
Ending Balance at Jun. 30, 2021 | 23,617,000 | $ 8,000 | 268,806,000 | (4,000) | (245,193,000) |
Ending Balance, shares at Jun. 30, 2021 | | 8,660,000 | | | |
Issuance of common stock under stock plan, net | (3,000) | | (3,000) | | |
Issuance of common stock under stock plan, net, shares | | 20,000 | | | |
Exercise of warrants | 15,000 | $ 1,000 | 14,000 | | |
Exercise of warrants, shares | | 6,000 | | | |
Stock-based compensation | 150,000 | | 150,000 | | |
Unrealized loss on available-for-sale investments | (2,000) | | | (2,000) | |
Net loss | (1,714,000) | | | | (1,714,000) |
Ending Balance at Sep. 30, 2021 | $ 22,063,000 | $ 9,000 | $ 268,967,000 | $ (6,000) | $ (246,907,000) |
Ending Balance, shares at Sep. 30, 2021 | 8,686,000 | 8,686,000 | | | |