Generic medications have been a godsend to global consumers, allowing millions to buy lifesaving drugs at significantly reduced costs. About 65% of all prescriptions filled in the U.S. are for generics according to the Generic Pharmaceutical Association. But consumers and physicians are becoming concerned as more patients are using generics to save money and more problems with medications and the US regulator of such medications—the US Food and Drug Administration (FDA)—have been in the press recently for such problems as inadequate foreign drug manufacturer inspections, uneven drug trials, and drug and drug component contamination. With the global manufacturing of pharmaceuticals, come the global problem and the related regulatory lapses.
Legally, a generic must contain the same active ingredient and the same action as its brand-name counterpart, which allows generics to share credit on brand name safety and efficacy trials. That being said, generics do have different inactive ingredients, which can affect how they are absorbed into the body, as was recently revealed with Wellbutrin and its generic counterparts. Generics can produce blood levels as much as 20% below or 25% above that of the original drug and still be considered “bioequivalent,” according to FDA guidelines. But, some patients are more sensitive to those differences than others and although people who experience problems with medications are advised to contact their doctors, the drug manufacturer, and the FDA’s MedWatch, last week’s FDA report on generic Wellbutrin revealed that consumers who complain may get no satisfaction.
GlaxoSmithKline PLC’s Wellbutrin XL and Teva’s generic Budeprion XL performed differently in lab “dissolution testings.” In Wellbutrin XL, tests showed that in two hours, about 8% of the bupropion was released; in the generic, 34% was released in the same period. Receiving a higher dose of bupropion up front could cause headaches, irritability, nausea, and seizures and even a return of depression or suicidal thoughts. Patients logged complaints at PeoplesPharmacy.com, a Web site for medication gripes where, “We’ve received hundreds of complaints about generic drugs in general. But with this one drug, all of a sudden—kaboom—right after it was approved,” says Joe Graedon, a pharmacologist who runs People’s Pharmacy.
The FDA also received about 130 complaints from December 2006 to January 2008, according to Dow Jones News Service. In response to its own investigation, the FDA reported last week that although there were “small differences” between the two formulations, “they are not outside the established boundaries for equivalence.” Some critics say the FDA was saying, “it’s all in their head,” but were more alarmed to read in the report that the FDA relied on tests comparing a lower dose of Wellbutrin and Budeprion—150 mg –when it first approved the 300 mg version in 2006. Also, the FDA did not have specific bioequivalence data on the 300 mg dose that generated the complaints. “Everybody involved in this whole chain—pharmacists, physicians, insurance companies, drug-store buyers—assumes the FDA approves every single generic formulation to prove that it isn’t harmful,” says Graedon. “We learned last week that that’s not the case.” In response, the FDA explained that it didn’t want to expose test subjects to the risk of seizures with the 300 mg dose. Sandy Walsh, an FDA spokeswoman, says this is common procedure for testing antidepressants and antipsychotics.