Cubist Proceeding with New Antibiotic - Drug Discovery and Development

LEXINGTON, Mass. (AP) – Cubist Pharmaceuticals Inc. said it will move an experimental antibiotic into late-stage clinical testing as a treatment for complex infections of the urinary tract and abdomen.

The company said it will start those trials of the drug, code-named CXA-201, by the end of 2011. Cubist announced the decision while reporting that CXA-201 met its goal in a midstage trial that evaluated it as a treatment for complicated abdominal infections.

The company said the study of 122 patients showed that a combination of CXA-201 and metronidazole, an antibiotic used to treat anaerobic bacteria, was about as effective as the broad-spectrum antibiotic Merrem.

Of patients whose response could be evaluated, Cubist said 91 percent treated with CXA-201 were cured. The company said that was similar to already-approved drugs. It said 94 percent of the patients treated with Merrem were cured in the study. Cubist said the drug was safe, and side effects were similar to those seen in other antibiotics used for abdominal infections.

Merrem, or meropenem, is an antibiotic marketed by AstraZeneca PLC. Cubist helped promote Merrem in the U.S. starting in 2008 and ending in June 2010, after a low-cost generic version reached the market.

The company also reported results from a midstage trial studying a drug candidate designated CB-183,315 as a treatment for severe diarrhea caused by bacteria called C. difficile. The trial compared the drug candidate to Vancocin, a powerful antibiotic. Cubist studied two doses of CB-183,315 and said both doses resulted in cure rates similar to Vancocin. The percentage of patients who were cured and later had a recurrence was also similar.

Cubist has not decided if it will advance CB-183,315 into late-stage testing. It plans to make that decision by the end of the year. By then, Cubist will be involved in the marketing of Dificid, a drug designed to treat C. difficile infections. Dificid was developed by Optimer Pharmaceuticals Inc. The Food and Drug Administration approved it in late May. Cubist will help sell the drug in the U.S. under a partnership with Optimer.

The company gets most of its revenue from sales of its antibiotic Cubicin, which is used to treat severe skin and bloodstream infections. U.S. sales of Cubicin rose to $153.7 million in the first quarter.

Date: June 16, 2011
Source: Associated Pres