Breast Cancer Drug Iniparib Fails Stage III Trials

NEW YORK (CBS/AP) - Tough news for women battling breast cancer - a promising drug to treat the toughest cases has failed in late-stage clinical trials.

French drugmaker Sanofi-Aventis SA had high hopes that their compound called iniparib would improve survival or slow the disease down. It did neither, the company said.

It's tough news for patients with "triple negative" breast cancer, a type that is very difficult to treat. As many as 20 percent of breast cancer patients are in this category, according to the company.

The study involved 519 patients whose cancer had metastasized or spread to other body parts. The trial compared a chemotherapy regimen including iniparib to one without it, evaluating its effects on overall patient survival and the amount of time patients lived before their disease resumed progressing or they died.

Sanofi-Aventis said there was not a significant difference between the regimen that included iniparib and the one that did not. Both regimens included the cancer drug Gemzar and the chemotherapy drug carboplatin.

However, the company said some patients who had been treated with one or two other therapies before enrolling in the trial did benefit from the iniparib regimen.

The disease is called triple negative because the tumors have normal levels of three proteins that are often found in high levels in breast cancer patients. Patients are usually treated with chemotherapy because the cancer does not respond to hormone-based drugs like tamoxifen, or drugs that target epidermal growth factors like Herceptin.