Stockholders' Deficit (Tables)

6 Months Ended

Jun. 30, 2013

Shares of Common Stock Authorized and Reserved for Future Issuance

At June 30, 2013, we have shares of common stock authorized and reserved for future issuance as follows:

Options to purchase common stock	10,438,038
Options available for future issuance	1,238,803
Convertible preferred Series A stock warrants	442,578
Common stock warrants	286,724
Total common stock authorized and reserved for future issuance	12,444,210