By Bill Berkrot
(Reuters) - Roche Holding AG's drug Avastin helped prolong the lives of women with advanced cervical cancer when added to chemotherapy in a late-stage clinical trial, likely paving the way to another major use for the multibillion-dollar medicine.
This marked the first study to demonstrate that a drug which blocks blood vessel formation in the tumor can prolong the lives of women with gynecologic cancers, researchers said.
In the study of 452 patients with cervical cancer that had spread or returned, those who received Avastin on top of chemotherapy on average lived for 17 months. That compared with a median overall survival of 13.3 months for those who received only chemotherapy. The result was considered to be statistically significant.
"Improvement in overall survival is a huge deal in this disease," Dr. Krishnansu Sujata Tewari, the study's lead investigator, said in an interview.
The current standard treatment for cervical cancer that has recurred or spread offers little hope, and patients tend to live for 12 months or less.
"We finally have a drug that helps women live longer," said Tewari, who presented data from the study on Sunday at the American Society of Clinical Oncology (ASCO) meeting in Chicago
Avastin, which had sales approaching $6 billion in 2012, is approved in the United States to treat cancers of the colon, lungs and kidneys, and - pending additional confirmatory data - has conditional approval for a type of brain cancer. In some overseas markets, it is also approved for ovarian and breast cancer. A conditional U.S. breast cancer approval was pulled after it failed to prolong survival in clinical trials.
An approval for treating advanced cervical cancer would open another large market for the medicine in patients for whom chemotherapy has been largely ineffective. About 4,000 women in the United States and 250,000 worldwide die each year from the disease.
The National Cancer Institute-sponsored study tested two chemotherapy regimens against the Avastin combination - cisplatin plus paclitaxel and topotecan plus paclitaxel - to assess if topotecan performed any better than commonly used cisplatin. Researchers found no significant differences in survival between the two chemotherapy regimens.
Avastin with either chemo agent also met secondary goals of the trial by improving progression-free survival (PFS), or the time before the disease began to worsen, to 8.2 months versus 5.9 months for chemotherapy.
Tumor shrinkage rates were higher in patients who received Avastin, known chemically as bevacizumab - 48 percent versus 36 percent for chemotherapy.
Researchers encountered no new or unexpected side effects from Avastin use in cervical cancer, while those that were observed did not significantly diminish patient quality of life.
"Not only did we not find any new side effects, but the overall side effects that we did see were all under 10 percent, which is considered to be an acceptable tradeoff when getting a survival gain," Tewari said.
(Reporting by Bill Berkrot; Editing by Michele Gershberg and Gunna Dickson)