Achillion lost $11.5 million, or 16 cents per share
That compares to a loss of $11.3 million, or 19 cents per share, in last year's quarter, when the company had fewer shares outstanding.
The drug developer reported no revenue in this year's second quarter, compared to about $56,000 last year after receiving reimbursement costs from a former collaboration with another hepatitis C treatment developer, Gilead Sciences Inc.
Analysts surveyed by FactSet expected, on average, a loss of 17 cents per share on about $100,000 in revenue.
Achillion's operating expenses climbed 2 percent to $11.6 million, as research and development and general and administrative costs rose.