After Wellbutrin fiasco, FDA takes a look at generic equivalence

The FDA's recent call to withdraw Teva Pharmaceuticals' ($TEVA) version of Wellbutrin XL didn't come in a vacuum. At the time, the agency also asked drugmakers selling their own Wellbutrin XL knockoffs to deliver more proof of their brand equivalence. And now, FDA says it's broadening scrutiny to other copies of extended-release medications.

Last month, the agency declared that Teva and Impax Laboratories' ($IPXL) version of Wellbutrin XL wasn't therapeutically equivalent to the brand. The decision came after years of patient complaints--and after FDA pooh-poohed the purported differences in efficacy. The agency finally conducted its own tests to find that the generic version didn't release the active ingredient at the same rate as the brand did.

The episode has FDA rethinking its position on generic equivalence. It's analyzing current equivalence testing processes, especially for extended-release formulations."This has actually prompted us to change our policy," Generic Drugs Director Gregory Geba told The New York Times.

The FDA's closer scrutiny comes at a time when some of the industry's biggest drugs are going generic. Government payers and insurers are eager to switch patients to the cheaper alternatives.

Generics advocates--including the Generic Pharmaceutical Association--vociferously defend the copycats, while critics applaud the agency's new caution. "This may be far more common than the FDA had realized," Consumer Advocate Joe Graedon, of the People's Pharmacy, told the Times. That remains to be seen, of course. Drugmakers, branded and generic alike, will be following this one closely.

- read the NYT piece

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