FDA: More study needed on birth control patch risk
|
Early findings suggest Johnson & Johnson’s contraceptive patch may cause more blood clots than birth control pills but more research is needed, U.S. health officials said on Friday.
One study showed women who used the patch, Ortho Evra, were twice as likely to develop blood clots than others who took the pill. A second study, however, found the risk was about the same with either method.
“We should caution that these results are preliminary and further evaluation is necessary to understand what these results mean,” said Dr. Daniel Shames, director of the Food and Drug Administration’s division of reproductive and urologic drug products.
“By chance, it’s possible that these (studies) are telling us the same thing,” Shames told reporters.
The chances of a clot forming remained “fairly low” with any contraceptive product, he added.
Both birth control pills and the patch increase clot risk because they contain the hormone estrogen. The patch is supposed to be replaced once a week, while the pill should be taken daily.
Women who use Ortho Evra are exposed to about 60 percent more estrogen than pill users, according to a warning added to the patch label in November 2005.
The warning says it is unknown if the patch is riskier than birth control pills. FDA officials said they do not plan any immediate changes to that language.
For every 10,000 women who take a hormonal contraceptive for a year, about three to five of them will develop a clot, Shames said. The risk is about one out of every 10,000 women who do not take hormonal contraceptives over a year.
Blood clots can lead to heart attacks and strokes. Data so far do not show any increase in those problems with patch users, Johnson & Johnson said. Shames said it could take 18 months to tell if there was a difference between the methods for those risks.
Johnson & Johnson said it worked with the FDA when it decided to commission the studies, which looked at health insurance records of thousands of women.
“Other analyses, including further evaluation of potential differences in risk factors between the two groups, are ongoing,” the company said in a statement.
Women who are concerned about the blood clot risk should consult a physician, Shames said.
“Some people don’t reliably take the pill… so the patch does offer them some alternative for contraception,” he said.
Shares of J&J fell as low as $58.74 before reversing direction. In afternoon trading, the shares were up 9 cents at $59.07 on the New York Stock Exchange.
Print Version
Tell-a-Friend comments powered by Disqus