10. WARRANTS

The following table presents information about warrants to purchase common stock issued and outstanding at December 31, 2020:


			Number of	Exercise Price as of
Year Issued	Defined Name	Classification	Warrants	December 31, 2020		Date of Expiration
2014	2014 Warrants	Equity	11	$	352.50	5/9/2021
2016	2016 Warrants	Equity	2,865	$	7,500.00	3/18/2021
2018	2018 Series A Warrants	Equity	211,921	$	6.98	6/25/2023
2019	2019 Placement Agent Warrants	Equity	15,168	$	4.50	11/21/2024
2020	March 2020 Series A Warrants	Equity	2,545,455	$	2.75	3/10/2025
2020	March 2020 Placement Agent Warrants	Equity	165,455	$	3.4375	3/5/2025
2020	March 2020 Series B Warrants	Equity	12,728	$	0.00001	Until Fully Exercised
2020	April 2020 Series C Warrants	Equity	1,680,240	$	1.62	10/17/2025
2020	April 2020 Placement Agent Warrants	Equity	111,491	$	2.1875	4/15/2025
2020	October 2020 Placement Agent Warrants	Equity	1,218,750	$	1.00	10/22/2025
2020	October 2020 Series A Warrants	Equity	18,750,000	$	0.80	10/27/2025
Total			24,714,084
Weighted average exercise price				$	2.01
Weighted average life in years						4.73

2019 Warrant Amendments

In November 2019, the Company entered into a Second Amendment to Warrant Agency Agreement and Warrants, (“the Second Ladenburg Warrant Amendment”), by and between the Company and Continental, as Warrant Agent, that amended the 2018 Series A warrants issued by the Company in the June 2018 underwritten public offering to reflect a reduced exercise price per share of $6.98 from $60.00. As a result of the Second Ladenburg Warrant Amendment, the fair value of the amended 2018 Series A warrants was re-measured immediately prior to the date of the Second Ladenburg Warrant Amendment with changes in fair value recorded as incremental warrant modification expense of $0.7 million in the Company’s consolidated statement of operations for the year ended December 31, 2019.