The company said the Food and Drug Administration asked it to suspend U.S. marketing and sales of the irritable bowel syndrome drug after Novartis released a retrospective analysis of data from more than 18,000 patients in the clinical trial database.
A recent analysis revealed a statistically significant imbalance in the incidence of cardiovascular ischemic events in patients taking Zelnorm compared with those taking placebo, Novartis said. These events included myocardial infarction, stroke and unstable angina pectoris.
The data showed that events occurred in 13 out of 11,614 patients treated with Zelnorm (0.11%), compared with one case in 7,031 placebo-treated patients (0.01%). All patients affected had pre-existing cardiovascular disease and/or CV risk factors.
Novartis said multiple studies do not suggest any constrictive effects of Zelnorm on coronary arteries. It said the FDA will hold an advisory panel hearing on the matter.