In a letter to GlaxoSmithKline, the FDA stated that the drugmaker exaggerated the benefits and downplayed the risks of breast cancer drug Tykerb in promotional materials sent to doctors. In response, a company spokesperson commented that GlaxoSmithKline will "work with the agency to address its concerns."
The FDA noted in its letter, posted to the agency website on Monday, that GlaxoSmithKline did not adequately warn doctors about Tykerb's risks, including the risk of decreased left ventricular ejection fraction. The drugmaker also left out precautions and warnings for patients with liver disease and pregnant women, the agency said. Furthermore, the FDA indicated that although the drug's approval was based on the findings from two studies, GlaxoSmithKline only included data from the trial that showed a higher decrease in the risk of tumour growth.
"These letters, which were part of the launch campaign for Tykerb, are misleading in that they omit and minimise the most serious and important risk information for Tykerb and selectively present efficacy information for Tykerb, thereby overstating the efficacy of the drug," the agency remarked. The FDA requested that GlaxoSmithKline halt distribution of the letters and come up with a plan to address the misleading promotional materials by December 6.