One death and a several patient hospitalizations of Phase II clinical trial patients has prompted Bristol-Myers Squibb to end development of its experimental hepatitis C drug, BMS-986094. The company idled the study August 1 because of a cardiac event among one of its patients. That patient has died. The company said in a statement that a total of 9 patients, including the patient who died, have been hospitalized.

BMS said in a statement that the cause of the unexpected medical problems has not been definitively established, but it does involve heart and kidney toxicity.

The experimental drug was a nucleotide polymerase inhibitor. The August 1 idling announcement triggered concerns about the mechanism, which is also being explored by other companies.