|
Prepaid expenses and other current assets (Details) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
|
Dec. 31, 2013
|
|---|---|---|
| Prepaid expenses and other current assets | ||
| Receivable from unsettled at-the-market equity transactions | $ 2,085 | |
| Prepaid contract research organization costs | 238 | 411 |
| Receivable related to tenant improvement allowance | 150 | |
| Interest receivable | 113 | 123 |
| Prepaid other | 55 | 23 |
| Prepaid expenses and other current assets | $ 2,641 | $ 557 |