Feb 14 (Reuters) - Merck & Co Inc said it would halt a late-stage trial of its drug in patients with mild to moderate Alzheimer's disease after an external panel pointed to a lack of effectiveness.
The company's shares were down 2.4 percent at $64.06 in after-market trading on Tuesday.
Merck said the external data monitoring committee, which assessed overall benefit or risk of verubecestat, determined that there was "virtually no chance of finding a positive clinical effect".
Patients with mild to moderate Alzheimer's disease exhibit detectable and worsening impairment of cognitive and functional abilities.
The company's announcement comes nearly three months after Eli Lilly and Co said its Alzheimer's treatment failed to slow declines in mental capacity of patients with even mild symptoms.
Merck said that another late-stage study for the treatment of people with prodromal Alzheimer's disease would continue and results from the study are expected by February 2019.
Patients with prodromal Alzheimer's disease have objective memory problems but relatively normal functioning in activities of daily living. (Reporting by Akankshita Mukhopadhyay in Bengaluru; Editing by Maju Samuel)