US drug giant Merck & Co has pulled the plug on an experimental combination of its diabetes drug Januvia and the cholesterol buster atorvastatin.

The Whitehouse Station, New Jersey-based firm said in a regulatory filing that it has decided to discontinue the clinical program for MK-0431E, which was in Phase III development.

The move, Merck said, was down to "business reasons", and a spokesperson for the company also confirmed to the media that there were no safety factors involved in the decision.

Merck already markets a combination of the dipeptidyl peptidase-4 (DPP-4) inhibitor Januvia (sitagliptin) with simvastatin, under the brand name Juvisync, which may have played a part in the move.

This is the second discontinued programme at the firm in the last few weeks - in October Merck decided to discontinue the clinical development program for MK-0524B, which combines extended-release niacin with laropriprant and simvastatin for cholesterol management, also for business reasons.