- Associated Press - Monday, December 5, 2011

WASHINGTON (AP) - Birth control drugs that were heavily promoted as having fewer side effects and the ability to clear up acne and other hormonal bothers are under new scrutiny from safety regulators.

Research suggesting that newer birth control formulations are more likely to cause blood clots than older drugs has prompted the Food and Drug Administration to consider new safety measures in meetings later this week. The increased risk is slight but significant because blood clots can cause heart attacks, strokes and blockages in lungs or blood vessels, which can be fatal.

Regulators could order new warning labels on several contraceptives that gained popularity in the last decade, including Bayer’s pill Yaz, which was the best-selling birth control pill in the U.S. for 2008 and 2009.

Yaz, its Bayer precursor Yasmin, and similar drugs use a version of a female hormone that appears to reduce side effects found in older drugs, including bloating and mood swings.

On Tuesday, a judge unsealed several court documents suggesting Bayer may have withheld data from FDA about the blood clots risks of its drugs. The documents stem from expert opinion gathered by personal injury lawyers suing Bayer on behalf of patients.

According to one document, Bayer drafted a white paper in 2004 to address “FDA concerns,” about clots with Yasmin. An early draft indicated that reports of blood clots with Yasmin were significantly higher than those for three other oral contraceptives. But that information was not included in the final paper submitted to the FDA, and instead the company said a more definitive study of blood clot risk would be forthcoming. That study did not show an increased risk.

“Based on the information that I have reviewed, and it is my opinion, that Bayer presented a selective view of the data, and that presentation obscured the potential risks associated with Yasmin,” wrote Dr. David Kessler, a former FDA commissioner, in his expert testimony. Kessler was paid for his time and opinion by the plaintiffs’ lawyers.

The FDA declined to accept the court documents for this week’s hearings, saying the deadline for submissions was last month, according to an emailed message from an agency officer.

A Bayer spokeswoman said the company had no comment on the material in the documents, noting the issues would be addressed at trial.

Bayer AG spent more than $270 million on TV and magazine advertisements for Yaz between 2007 and 2010, according TNS Media Intelligence. Such big-budget campaigns are rare for birth control products. One advertisement featured young women singing the Twisted Sister anthem, “We’re Not Gonna Take It,” while popping balloons labeled “moodiness,” “bloating” and “acne.”

Sales of Yaz have fallen since regulators forced Bayer to correct advertisements that overstated Yaz’s benefits and as safety questions drew scrutiny in both the U.S. and Europe.

FDA also is reviewing research on clot risks associated with Johnson & Johnson’s weekly Ortho Evra patch, which is marketed as an “option for busy women who are looking to simplify life.” The drug uses a different version of the female hormone progestin than the pills under scrutiny.

Millions of women have used the products since they launched a decade ago, but recent studies comparing the medical histories of women taking the newer drugs to older ones suggest a slightly higher risk of blood clots in the legs and lungs. Last year, the U.S. market for female contraceptive drugs totaled $3.4 billion, according to IMS Health.

Sorting out the blood clot risk of birth control drugs is especially difficult because all hormone-based drugs increase the risk of clotting. Further complicating the issue is that clots can be caused by factors such as smoking, obesity or family history.

Yaz, Yasmin and other pills containing a synthetic hormone called drospirenone are the focus of a discussion Thursday. The next day’s meeting focuses on the Ortho Evra patch, which uses the hormone norelgestromin.

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