Merck & Co has reported promising progress for its investigational Alzheimer's drug MK-8931 after a positive safety review.

A data monitoring committee has looked at interim safety data from the Phase II/III EPOCH study which included a safety cohort of 200 patients with mild to moderate Alzheimer's treated with the drug for at least three months. Based upon the DMC’s recommendations, Merck will continue enrollment of the EPOCH study and will initiate dosing in a new Phase III study (called APECS) evaluating MK-8931 in patients with amnestic mild cognitive impairment due to Alzheimer's.

The EPOCH trial is now anticipated to enroll up to 1,960 patients, while Merck is looking to recruit 1,500 participants for APECS.

MK-8931 inhibits the beta secretase (BACE) enzyme, which is believed to play a key role in the production of the amyloid beta that accumulates in the brain to form amyloid plaques in patients with the disease. However, this class of treatment suffered a setback in June when Eli Lilly halted a Phase II trial of its BACE inhibitor due to potential liver problems.

The DMC recommendation is clearly a positive for Merck and ISI analyst Mark Schoenebaum issued a research note noting that the safety profile of MK-8931 "is at least somewhat better than prior molecules".