A new Avastin study has confirmed the cancer drug’s link with serious, life-threatening gastrointestinal perforations. According to researchers at Stony Brook University Medical Center in Long Island, New York, people taking Avastin developed such perforations – holes in the gastrointestinal tract – at twice the rate that occurred among patients not taking the drug. Avastin already bears a Black Box warning on its label regarding its association with gastrointestinal perforations.
Avastin was the first approved therapy designed to inhibit angiogenesis, the process by which new blood vessels develop and carry vital nutrients to a tumor. Avastin was approved by the Food & Drug Administration (FDA) in 2004 to treat metastatic colon cancer, and in 2006, the agency approved it as a treatment for non-small cell lung cancer. Last year, the FDA also approved Avastin as a metastatic breast cancer treatment, and earlier this month, it was approved to treat glioblastoma multiforme, an incurable brain cancer.
The Stony Brook study involved 12,300 cancer patients in 17 clinical trial. Of those patients, 6,490 took various doses of Avastin. According to a report on WebMD, about 1% of Avastin patients developed holes in the gastrointestinal tract – twice the rate seen in patients not taking Avastin. The risk was highest in people treated with higher doses, as well as those whose cancer had spread, and in people suffering from colorectal or kidney cancers. Also, of all of the patients in the study who developed such perforations, more Avastin patients (22%) died from the complication, compared to those taking another drug (18%), WebMD said.
Avastin has been the subject of other safety concerns. When the FDA approved Avastin for breast cancer patients, it did so against the recommendation of its own advisory panel. The FDA advisory panel recommendation came after agency staffers posted documents on the FDA website noting that while Avastin did extend the period prior to patients’ breast cancer becoming worse, treatment with the drug did not markedly increase survival time. The FDA documents also pointed out that Avastin caused serious side effects, including cardiovascular problems, bowel perforations, and a few deaths. The FDA staff said that those side effects included several patient deaths that were “probably or definitely” due to Avastin.
Avastin has also been linked to a higher risk of blood clots in the veins. And in December, Genentech reported that some Avastin patients had experienced eye inflammation when it was used off-label to treat an eye condition.