Serono has completed the patient enrolment in a multi-national Rebif (interferon beta-1a) versus Copaxone (glatiramer acetate) comparative clinical trial. This two-year trial is designed to compare the efficacy of the two therapies in patients with relapsing remitting multiple sclerosis (RRMS), who were previously untreated with disease modifying therapies.

Over 700 patients have been enrolled and are being treated either with Rebif 44 mcg administered three times per week by subcutaneous injection or Copaxone 20 mg administered daily by subcutaneous injection. The primary outcome of the trial is time to first relapse. Secondary outcomes include assessments of MRI (magnetic resonance imaging) brain scans and disability progression. Physicians performing the neurological examinations and radiologists assessing the MRI scans do not know what treatment each patient has been allocated to, Serono said in a release.

"We believe that a head-to-head trial is necessary to provide scientific data that can be used to compare different therapeutic options. In the past, we have provided such data, comparing Rebif with Avonex in the landmark EVIDENCE trial, which allowed Rebif to gain market approval in the US under the terms of the Orphan Drug Act," said Paul Lammers, CMO of Serono, Inc. "The ongoing Rebif versus Copaxone trial will provide comparative data that will support an evidence-based approach for rational treatment decisions in multiple sclerosis, and we expect the data to support Rebif as the foundation therapy for treatment of multiple sclerosis," he added.

Rebif is the only approved MS therapy proven in a four-year clinical study in all three key measures of treatment effectiveness: reducing MRI lesion area and activity1, reducing relapses and delaying the progression of disability. Rebif is the most prescribed MS disease modifying drug outside the US and is the fastest growing one in the US.