July 19 (Reuters) - Cubist Pharmaceuticals Inc's revenue beat market expectations as sales of its lead drug Cubicin soared, sending its shares up as much as 5 percent in extended trade.
Total revenue rose 30 percent to $231 million.
The company said revenue from Cubicin, an antibiotic injection approved in the United States to treat bacterial skin infections, rose 20 percent to $212 million.
It posted a second-quarter net income of $43.1 million, or 58 cents per share, compared with a loss of $20.6 million, or 34 cents a share, a year earlier.
Cubist recorded a contingent consideration of $81.8 million in the year-ago quarter relating to potential milestone payments to stockholders of Calixa, which it acquired in 2009.
Excluding one-time items, the company earned 68 cents per share.
Analysts were expecting a profit of 45 cents per share on revenue of $226.1 million, according to Thomson Reuters I/B/E/S.
Cubist is also developing treatments for bacterial infections, hospital-acquired diarrhea and opioid-induced constipation in chronic non-cancer pain.
Shares of Lexington, Massachusetts-based Cubist were up 5 percent at $42.50 after the bell. They closed at $40.63 on Thursday on the Nasdaq.