Last week, FDA attention on two drugs – Avandia and Plan B – may change things for, respectively, people with diabetes and many women seeking emergency contraception.
As reported in the New York Times, the FDA removed some restrictions how doctors prescribe and patients use Avandia. A couple of years ago, as we blogged Avandia was removed from the general market because the FDA said it posed a major risk of heart attack.
It was still available, but allowed to be prescribed only by certified physicians and taken only by patients who were informed of the risks and filled their prescriptions by mail order through specific pharmacies. The FDA limited the drug to patients already successfully treated with it or to those for whom it’s pretty much a last-ditch effort to control blood glucose medically.
Now, the FDA says that new research shows that Avandia does not increase the chances of heart attacks. The “new” data came from an outside review of an old clinical trial conducted by GlaxoSmithKline, which manufactures the drug. As we blogged in June, the panel that reviewed the data had recommended that the restrictions be lifted.
The Times story said that some researchers had criticized the original trial as flawed and resisted revisiting a case that had been resolved. Others questioned its independence, because Glaxo had paid for it.
The FDA and Glaxo claimed that the data was the best the medical community had about a potentially lifesaving drug, and that the high incidence of diabetes compelled its review. And the FDA said the data showed no elevated risk for Avandia compared with standard diabetes drugs.
But Avandia’s future popularity remains a cloudy forecast. After a 2007 analysis showed that taking it regularly could increase the risk of heart attack, Avandia went from a blockbuster drug to a marginal drug used by just a few thousand people.
Doctors responding to its renewed lease on life said the FDA’s action was unlikely to reinvigorate is market. It was widely discredited in the U.S., and withdrawn from the market in Europe in 2010. And Glaxo paid $3 billion in fines partly because it failed to report safety updates about Avandia.
As we’ve advised, unless there are no other options, choose older medications over new ones. The safest option is to let at least five to seven years elapse so a drug’s true safety profile can be drawn.
In the case of the drug known as Plan B, it wasn’t its harmful effects that attracted FDA scrutiny, but its failure to work in a large segment of its market.
As reported by NPR, the feds are reviewing whether Teva Pharmaceuticals, which manufactures the contraceptive compounded with the hormone levonorgestrel, should to change its label. Apparently, the drug widely known as the “morning after pill” doesn’t work for many overweight, obese and unusually tall women.
European companies that make a similar product have relabeled their version after studies showed that levonorgestrel starts losing its effectiveness in women who weigh as little as 165 pounds, and stops working completely for those who weigh more than about 175 pounds.
According to NPR, the fact that Plan B doesn’t prevent pregnancy after unprotected sex in overweight or obese women came as an accidental finding of a broader study that was comparing the effectiveness different kinds of emergency contraceptives. After a long political battle, Plan B was approved for sale to even teenagers without a prescription.
It took a while until studies included enough subjects who were sufficiently overweight, such as in the U.S., where nearly 2 in 3 adult women are considered overweight or obese.
Still, there was anecdotal evidence. One medical director of a reproductive health project in New York City interviewed by NPR said many of her overweight patients have told her, ” ‘Yeah, I got pregnant using that.’ So they’ve had the experience already of it not working.”
Researchers aren’t sure why the drug, which costs $50 a dose, doesn’t work for hefty patients. It might have to do with metabolism, or with the volume of the medication in the bloodstream. No one knows if a higher dose for these women would work. That would have to undergo clinical tests.
But medical professionals say that now that the effect is known, manufacturers of all products containing levonorgestrel – not just Plan B, but all its generic copies – should be required to tell women about it.
In a statement, the FDA said it’s “currently reviewing the available and related scientific information on this issue,” and will determine “what, if any, labeling changes to approved emergency contraceptives are warranted.”
In the meantime, women who weight more than 165 pounds should choose other forms of contraception than Plan B or generic meds with levonorgestrel.