Biogen Inc said on Friday it has decided to withdraw the marketing authorization application for its troubled Alzheimer's drug, aducanumab, in Europe after it failed to convince the regulator of the drug's benefits.

The drugmaker said the move follows its interactions with the European Medicines Agency that suggested data provided so far would not be enough to support an approval. The agency had in December rejected the drug and Biogen had sought a re-examination of its decision.

"We stand by the safety and efficacy of aducanumab, and we look forward to upcoming data readouts to continue to provide important information on the science of this new class of compound," said Priya Singhal, interim head of R&D at Biogen.

The drug is only approved in the United States, a controversial decision since only one of two late-stage trials showed that it helped slow cognitive decline. The U.S. approval was based on the drug's ability to clear amyloid plaque from the brain, which believes could likely help slow cognitive decline for Alzheimer's patients. But critics and the U.S. Centers for Medicare and Medicaid Services (CMS) did not agree with the decision.

CMS earlier this month limited the drug to patients in clinical trials, significantly restricting its use. Analysts expect minimal sales of the drug in the next few years.