Capital Stock (Tables)

12 Months Ended

Dec. 31, 2016

Authorized, Issued and Reserved shares of common stock

As of December 31, 2016 the Company has 229,381,059 shares of common stock outstanding and the following shares of common stock are reserved for issuance:

	Reserved for		Strike
	issuance		Price		Expiry
Shares reserved under outstanding stock options and options available for grant		52,092,463
Rights associated with Employee Stock Purchase Plan		70,122
Warrants to purchase common stock associated with the 2016 Debt Restructuring		5,169,577	$	0.0994		Aug 1, 2026
Warrants to purchase common stock associated with July 2016 private placement		56,262,571	$	0.0994		Jul 29, 2023
Warrants to purchase common stock associated with December 2014 private placement		50,189,431	$	0.1003		Dec 23, 2021
Warrants to purchase common stock associated with December 2014 venture loan and security agreement		2,492,523	$	0.1003		Dec 23, 2024
Warrants to purchase common stock associated with September 2014 consulting agreement with Danforth Advisors		100,000	$	0.2500		Sep 8, 2024
Outstanding warrants issued in May 2013, vesting August 2013		14,426,230	$	0.2745		Aug 9, 2020
Outstanding warrants issued in May 2013, vesting May 2013		20,655,737	$	0.2745		May 17, 2020
Outstanding warrants issued in June 2012		437,158	$	0.2745		Jun 29, 2017
Total common shares reserved for issuance at December 31, 2016		201,895,812
Total common shares issued and outstanding at December 31, 2016		229,381,059
Total common shares outstanding and reserved for issuance at December 31, 2016		431,276,871

Black-Scholes Pricing Model Assumptions to Determine Fair Value of Warrants

The fair value of the 2016 Warrants at issuance was $6.5 million. Fair value of the 2016 Warrants was calculated using the following inputs in a Black-Scholes model:

	July 29, 2016
Risk-free interest rate		1.52	%
Expected life		7 years
Expected volatility		147.03	%
Dividend yield		0	%

Principal payments due under the terms of Loan Agreement

Principal payments due under the terms of the Loan Agreement and the 2016 Debt Restructuring are as follows:

2017		2,304,545
2018		1,920,455
	$	4,225,000

Lender Warrants [Member]

Black-Scholes Pricing Model Assumptions to Determine Fair Value of Warrants

Fair value of the 2016 Lender Warrants was calculated using the following inputs in a Black-Scholes model:

	August 1, 2016
Risk-free interest rate		1.78	%
Expected life		10 years
Expected volatility		138.81	%
Dividend yield		0	%