Serono gets lift from head-to-head study of Rebif versus Avonex

Serono of Switzerland may be able to launch its multiple sclerosis drugRebif (interferon beta-1a) in the important US market, after having demonstrated superiority to Biogen's Avonex (interferon beta-1a) in a head-to-head clinical trial.

Although Rebif is already available in 67 countries around the world, and saw first-quarter sales surge 71.3% to $83 million, Serono has been prevented from introducing it in the USA because Biogen has orphan drug exclusivity for Avonex there, extending into 2003. The only way for the Swiss firm to circumvent this protection is to demonstrate a clinical advantage over Biogen's drug.

The EVIDENCE (EVidence for Interferon Dose Effect: European North American Comparative Efficacy) study was designed to compare the two drugs in the relapsing-remitting form of MS, based on pre-defined endpoints agreed with the US Food and Drug Administration, and enrolled 677 patients. The primary endpoint of the study showed that patients treated with Rebif (44mcg three times weekly) had a 90% greater chance of remaining relapse-free during the 24-week period of observation (an odds ratio of 1.9) compared to patients treated with Avonex (30mcg once weekly; p=0.0005). The finding is based on a 32% relative reduction in the proportion of patients experiencing relapses on Rebif as compared to Avonex.