Safety concerns have prompted Janssen to pull the plug on a development programme testing the BACE inhibitor atabecestat for Alzheimer’s disease.

The Johnson & Johnson group said liver enzyme elevations had been observed in some study participants who received the drug.

Following a thorough evaluation of all available liver safety data from its studies, the firm concluded that the benefit-risk ratio “is no longer favorable to continue development” of atabecestat for patients with late-onset preclinical stage Alzheimer’s disease.

Consequently, it is stopping the screening, randomisation and dosing of the drug in the Phase IIb/III EARLY study in late-onset preclinical stage Alzheimer’s disease and in a Phase II long-term safety study.

Evidence suggests that inhibiting BACE could reduce amyloid plaque formation and modify the progression of Alzheimer's disease, and several other drugmakers - including Lilly and Novartis - have investigational drugs targeting this mechanism.

However, earlier this year Merck & Co terminated a Phase II/III trial of its experimental BACE inhibitor verubecestat after it emerged there was “virtually no chance of finding a positive clinical effect”.