FDA has called in the cavalry for help reviewing the safety of Bayer's Yaz line of birth-control pills. The agency plans to convene an advisory panel in December to sift through the evidence on the contraceptives--and their generic equivalents--which contain drospirenone, a synthetic version of the hormone progestin. And in the meantime, it's warning women using this type of birth control and doctors prescribing it to be mindful of the potential risks.
The question is whether the pills increase the risk of blood clots compared with other types of birth-control drugs. Hormonal contraceptives have long been linked with a risk of venous thromboembolism, or VTE, but early data from an FDA-funded study of 800,000 women suggests that drospirenone pills boost that risk by 50%. Earlier studies published this year in the British Medical Journal found double to triple the usual clotting risk, HealthDay reports, whereas some other trials found no difference in risk.
FDA says it has wrapped up its review of the BMJ studies and is continuing to analyze data from its own research. But "[g]iven the conflicting nature of the findings," the agency said, it has scheduled a joint meeting of two advisory committees, one devoted to reproductive health and the other focused on drug safety.
Bayer has said that its own analysis of available data shows that the clotting risk with its Yaz line of pills is "comparable" to the risk with other birth-control pills, the Wall Street Journal reports. The company also says it's working with FDA on the safety review, but tells Pharmalot that it hasn't yet had the chance to see data from the FDA study.
Meanwhile, the company faces thousands of lawsuits claiming that the Yaz line of products is riskier than other BCPs--and that Bayer heavily marketed the pills without disclosing those risks.