Rosiglitazone restricted to patients who can't take other drugs

The use of rosiglitazone (Avandia) will be restricted to patients who cannot control their diabetes using other medications, the FDA announced last Thursday.

Manufacturer GlaxoSmithKline (GSK) will be required to develop a restricted access program, under which rosiglitazone will be available to new patients only if they are unable to achieve glucose control on other medications and are unable to take pioglitazone (Actos). Physicians who prescribe rosiglitazone will have to attest to and document their patients' eligibility, according to the FDA press release. Patients will be required to review statements describing the cardiovascular safety concerns associated with the drug.

Current users of the drug will be able to continue taking rosiglitazone if they appear to be benefitting and they acknowledge their understanding of the potential risks. The FDA also ordered GSK to convene independent scientists to review the results of the RECORD study. During the FDA review of RECORD, questions arose about potential bias in identifying cardiovascular events due to the study's open-label design, FDA administrators wrote in a perspective published Sept. 23 in the New England Journal of Medicine.

The FDA leaders also explained the reasoning behind their restriction of rosiglitazone. The evidence of the drug's risks was not definitive but “there was no reliable evidence to refute these cardiovascular safety concerns,” the article said. Less regulation, such as a label change, would not provide adequate assurance that use of the drug would be limited to appropriate patients. However, removing the drug from the market would take away the glycemic control benefits seen by patients who have reasons not to take pioglitazone. For example, the FDA's recently announced investigation of an association between pioglitazone and bladder cancer may dissuade patients with a history of that disease from taking pioglitazone, the article noted.