Novartis had suspended U.S. sales of Zelnorm in 2007 at the request of the U.S. Food and Drug Administration because a safety analysis found it increased the risk of heart attack, stroke and chest pain, compared with placebo.
Zelnorm, which first went on sale in 2001, was approved to treat irritable bowel syndrome with constipation. It had sales of $561 million in 2006, the last full year before its withdrawal.
The withdrawal sparked a number of lawsuits. Novartis said in its earnings release it's a defendant in about 135 cases brought in U.S. and Canadian courts.