Biotech drug developer CombinatoRx Inc. said Thursday it turned a $25.2 million profit in the final quarter of 2009, as it cut research costs and saw big gains from the completion of an acquisition.

The Cambridge, Mass., company said it earned 57 cents per share in the three months that ended Dec. 31. That compares with a $15.2 million loss, or 43 cents per share, in the final quarter of 2008.

Revenue more than doubled to $8.6 million from $3.5 million.

CombinatoRx shares climbed 13 cents, or 10 percent, to $1.39 in Thursday morning trading.

CombinatoRx completed an acquisition of the privately held Canadian company Neuromed Pharmaceuticals Ltd. in the quarter. Chief Financial Officer Justin Renz said CombinatoRx recognized gains totaling $21.9 million from that deal.

A litigation settlement led to a $3.7 million gain, and the company also cut research and development expenses to $3.1 million in the fourth quarter from $9.8 million in the last quarter of 2008.

For the full year, CombinatoRx, which focuses on treatments for pain and inflammation, earned $15.4 million, or 41 cents per share, on $17.3 million in revenue.