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Will the FDA Yank Bayer's Risky Birth-Control Pill Yaz?

When the FDA meets on Dec. 8 to review the Bayer (BAYRY) birth control pill Yaz, it will be a test of whether drugs should be allowed on the market if, although they may be effective, they offer no advantages over other drugs but carry extra risks.

Preliminary results of an FDA-funded study of Yaz and similar drospirenone-based contraceptives show they carry a 1.5-fold increase in the risk of potentially lethal blood clots compared to older hormonal contraceptives. That study follows six others, four of which have shown an increased clot risk for Yaz and its ilk.

Meanwhile, 9,300 lawsuits have been filed against Bayer as of Q2 2011, alleging Yaz caused blood-clot related strokes, heart attacks and fatalities, as well as gallbladder problems. More than 190 women have died while taking Yaz.

The DrugCite database of adverse event information culled from the FDA shows that blood-clot events are more common for pills containing drosperinone than for levonorgestrel, an older version of the progestin ingredient in contraceptive pills:

  • Most Common Drospirenone Adverse Events
  • Pulmonary Embolism: 119
  • Deep Vein Thrombosis: 99
  • Gallbladder Injury: 57
  • Thrombosis: 20
  • Most Common Levonorgestrel Adverse Events
  • Pulmonary Embolism: 17
  • Deep Vein Thrombosis: 10
  • Thrombosis: 9
  • Gallbladder Injury: 0
With the evidence showing that Yaz carries risks that equivalent drugs do not, the FDA will have to ask whether it is justified in allowing it to remain on the market. That's a sensitive economic issue in the drug industry. Some patients want extra options, even if they carry risks, companies argue. Companies also tend to shy away from head-to-head comparisons of drugs' safety, preferring drug vs. placebo tests, precisely because they might find out that their drug offers only disadvantages.

The issue has been dragging on for years and has become more urgent because Yaz has gone off patent and now faces competition from cheap generic versions. In Q2 2011, Bayer earned €263 million in revenues from the pill, down 9 percent from the year before; it's still Bayer's third-largest product. On top of that are all the women taking generic versions with names such as Ocella, Safyral, Syeda and Zarah.

The fact that Yaz's sales have held up even though it's more expensive shows that when it comes to contraception, women like to stick with something they feel works, especially if it isn't associated with weight gain, acne and mood swings.

The problem is that you can't feel blood clots in your veins until it's too late -- which is why the December FDA meeting is so important.


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