Moody's said Biogen Inc.'s discontinuation of clinical trials for the experimental Alzheimer's drug aducanumab is credit negative for the company.

There is no impact on Biogen's Baa1 senior unsecured rating or the stable rating outlook.

The Cambridge, Mass.-based company, together with Japan's Eisai Co. Ltd., stopped two late-stage clinical trials of the investigational Alzheimer's drug after a futility analysis conducted by an independent data monitoring committee showed that the studies were unlikely to meet their main goals.