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May 14 (Reuters) - Biogen BIIB.O said on Thursday it was advancing its experimental Alzheimer’s drug to late-stage trials despite the treatment failing to meet the main goal of a mid-stage study.

Shares of the company were up over 6% in premarket trading.

Cambridge, Massachusetts-based Biogen was testing the drug, diranersen, in patients with early-stage Alzheimer’s disease.

In the 416-patient trial, the drug failed to show that higher doses worked better than lower ones on a standard scale used to track dementia severity at 76 weeks, the company said.