The FDA released its quarterly list of early investigations into health problems reported with various drugs on Wednesday.
On the list, the agency said it was probing cases of thrombotic thrombocytopenic purpura (TTP) in patients treated with Effient, a blood thinner from Lilly and Daiichi Sankyo. TTP is a rare but potentially fatal blood disorder.
Effient's makers have seen one, or "possibly two," reports of TTP with the drug since its approval a year ago, Lilly spokeswoman Tammy Hull said. No cases were recorded in clinical trials, she said.