Biogen Idec (BIIB 4.56%) announced today that results of a new phase 3 clinical trial show significant reductions in relapse rates for multiple sclerosis patients using peginterferon beta-1a .

In the 1,500-patient study, the injectable drug reduced relapses for 39% of those receiving biweekly doses, and 26% for those receiving monthly doses. In addition, peginterferon beta-1a was also found to decrease the risk of disability progression and reduce the number of new or enlarging brain lesions.

"If approved, peginterferon beta-1a will represent an innovation that offers patients a less frequent dosing schedule of no more than 26 doses annually, as well as a significant reduction in relapses and disability progression," said Gilmore O'Neill, Biogen's vice president of global neurology late-stage clinical development. "Interferons are an important and widely used option for many patients. As a leader in MS, Biogen Idec has the deepest MS pipeline in the industry, and we remain steadfast in our commitment to study compounds that target a broad range of patients' needs."

Peginterferon is a longer-lasting version of Biogen's Avonex, which pulled in $2.7 billion in revenue for FY 2011. As a result of the trial's success, Biogen expects to submit the new drug for U.S. and E.U. regulatory approval this year.

Biogen's stock closed 1.99% up today .