Merck halts Vertex cancer drug trial on heart risk

LOS ANGELES, Nov 20 (Reuters) - Vertex Pharmaceuticals Inc (VRTX.O) said Merck & Co Inc (MRK.N) halted enrollment on trials of their lead investigational Aurora kinase inhibitor cancer drug due to a potential heart safety issue.

The companies said trials involving the drug, known as MK-0457 or VX-680, were suspended pending a full analysis of efficacy and safety data after preliminary data showed QTc prolongation in one patient.

QTc prolongation is a disorder of the heart's electrical system that can result in an irregular heartbeat and is associated with increased risk of sudden cardiac death. (Reporting by Lisa Baertlein; Editing by Braden Reddall)