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FDA Cites Blood-Clot Risk Tied to Bayer Birth-Control Pills

October 27, 2011

(Adds Bayer response in the fourth and fifth paragraphs)

Oct. 27 (Bloomberg) -- U.S. regulators warned there may be an increased risk of blood clots connected with birth-control pills made by Bayer AG, and said the issue will be further evaluated in a meeting with advisers in December.

Women taking pills containing the hormone drospirenone were 74 percent more likely to experience clots than those on low- estrogen pills, the Food and Drug Administration said in a report released today. An FDA advisory committee will meet Dec. 8 to discuss the findings.

Sales of the Yaz family of birth-control pills fell 13 percent in 2010 to 1.11 billion euros ($1.57 billion), making them the company’s second-biggest drug. North American revenue from the pills has fallen as the German drugmaker, based in Leverkusen, faces competition from generics made by Teva Pharmaceutical Industries Ltd. The company earlier today said the pill’s risks weren’t higher than that of other oral contraceptives.

“We believe that the overall potential risk that Yaz or Beyaz present to patients is absolutely compared with that of other oral contraceptives,” said Joerg Reinhardt, head of Bayer’s HealthCare unit, in a conference call with analysts today before the FDA released the study results.

After the FDA made its statement, Astrid Kranz, a Bayer spokeswoman, said the company will comment further at the agency’s panel in December.

Similar to Progesterone

Drospirenone is similar to the natural female hormone progesterone. The study evaluated data from 835,826 women ranging in age from 10 to 55 taking pills containing the hormone over time, including Bayer’s Yaz, Beyaz and Angeliq, the FDA report said.

The FDA findings come on top of recent studies suggesting newer birth control pills, including those containing drospirenone, carry twice the risk of potentially deadly blood clots than older contraceptives.

Researchers in Denmark used the country’s health-care data base of women between the ages of 15 and 49 from 2001 through 2009 to find dangerous clots known as venous thromboembolism developed in 4,246 women for the first time during the study. The researchers reported their results in the British Medical Journal this week.

--With reporting by Catherine Larkin in Indianapolis and Michelle Fay Cortez in Minneapolis. Editors: Reg Gale, Bruce Rule

To contact the reporter on this story: Adriel Bettelheim in Washington at; Naomi Kresge in Berlin at

To contact the editor responsible for this story: Adriel Bettelheim at; Phil Serafino at

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