Generic Wellbutrin Gets FDA Backing, Despite User ComplaintsApr 18, 2008 | Parker Waichman LLP Despite complaints from patients, the US Food and Drug Administration (FDA) says a cheaper, generic version of GlaxoSmithKline PLC's Wellbutrin XL antidepressant is safe and effective. The FDA said it received 85 reports from patients who switched from Wellbutrin XL to either Teva Pharmaceutical Industries Ltd. or Impax Laboratories Inc.'s cheaper generic. Of these, 78 people said their depression returned once they stopped taking the name brand and began a generic. Others reported new or worsening side effects including headaches, fatigue, anxiety, and digestion issues.
"The question is whether the reported lack of efficacy and/or new onset side effects in these patients who switched suggest a problem with the generic product ... or have some other explanation," the FDA said. Agency scientists reviewed 300-milligram versions of the two drugs, which both use once-a-day formulations of the chemical bupropion. According to the FDA, half of the patients who resumed taking the name-brand drug said they improved. The FDA said it would continue to monitor the issue. The FDA does not subject generics to the same level of scrutiny as brand name drugs; therefore, there is concern that these problems do not reflect isolated incidents.
Meanwhile, previous studies comparing Teva’s generic Budeprion XL with Wellbutrin XL found that although the generic contained the same active ingredient as the brand name, it performed differently in lab tests. The consumer advocacy website ConsumerLab.com conducted an investigation following hundreds of complaints from former Wellbutrin XL users that Budeprion XL was not working as well. ConsumerLab.com found both versions contained the stated amount of the active ingredient bupropion; however, differences occurred when the drugs underwent “dissolution testings.” Both medications are time-released, meaning the active ingredient is released over a period of many hours. 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 brupropion up front could have caused the headaches, irritability and nausea so many generic users complained of. Worse, more serious problems, like a return of depression or suicidal thoughts, could be the result of less medication entering the patients’ bloodstreams later in the day.
Add all this to the FDA’s uneven inspection processes and issues with foreign-manufactured drug components. Drug imports increased in the past five years, but inspection funds dropped. While 3,250 non-US plants were subject to FDA inspections last year, it only conducted 1,445 in the last five years. It’s worse in China where the FDA averaged just 15 inspections in each of the last five years, despite that there are 714 plants shipping drug products to the US. If China's 17% annual growth rate for drug exports continues, they will produce about 25% of the world's pharmaceutical ingredients by 2010. "Millions of FDA-regulated products are imported into the country each year from foreign facilities that have never been inspected by FDA and, with current appropriations, never will be," according to the FDA Science Board's subcommittee on science and technology. The head of the FDA study group, in an interview, held out little hope the FDA is coming to grips with its challenges.