A diabetes drug co-developed by Boehringer Ingelheim and Vitae has failed to significantly reduce blood sugar in a Phase II trial.

The trial was testing VTP-34072 – an HSD1 inhibitor, also known as BI187004 ­– as an add-on to the common diabetes treatment metformin in overweight type 2 diabetics.

The firms are still awaiting results from a study testing the drug as a monotherapy. Boehringer has said that it will decide the next steps for VTP-34072 once it has both sets of data.

"The metabolically complex, overweight type 2 diabetic patient population is in need of novel mechanisms of action that can address their overall risk profile," said Richard Gregg, chief scientific officer of Vitae. "We are anxious to learn more about VTP-34072 when the study is completed and fully analysed."

This is the second setback for the partnership after Boehringer put Phase I trials of their Alzheimer’s drug BI1181181 on hold in February. The drug is part of the promising BACE inhibitor class, but skin rashes were observed in some patients taking it.

Vitae received an upfront payment of $74.2 million from Boehringer as part of the diabetes deal and $78.2 million for the Alzhiemr’s partnership. Both deals also have the potential for milestone payments – up to $278 million in diabetes, of which $6 million has already been paid, and $326 million in Alzheimer’s.