8. Long-Term Debt

In August, 2010 the Company obtained a $15.0 million loan commitment from Mid Cap Financial (“Mid-Cap”) and Silicon Valley Bank (“SVB”) and borrowed $10.0 million at the time the facility was created. In December 2010, the Company accessed the remaining tranche of $5.0 million. In June 2012, the company terminated the facility, paid the entire outstanding balance and recorded a loss on debt extinguishment of $992,000, which included a 5% prepayment fee of $615,000 and the write off of unamortized deferred financing fees and discounts of $377,000. In connection with the loan during 2010, the Company issued warrants to lenders to purchase an aggregate of 64,674 shares of Series C-3 convertible preferred stock. The fair value of the preferred stock warrants issued was $219,322 on the dates of issuance and was based on observable inputs using quoted market values and the income approach as derived by the Black-Scholes model. The terms of these preferred stock warrants are described in Note 9.

Interest paid was $655,834, $0 and $0 for the years ended December 31, 2012, 2013 and 2014, respectively.