A randomized double-blind trial of comparative efficacy and safety of Avonex and CinnoVex for treatment of relapsing-remitting multiple sclerosis

Interferon beta is currently the first line treatment of relapsing-remitting multiple sclerosis (RRMS). Different formulations of interferon beta are available. Avonex and CinnoVex are two interferon beta-1a being prescribed by neurologists in Iran. The aim of this study was to compare the four and half year outcome of Avonex and CinnoVex in patients with RRMS. A total 186 of patients with definite RRMS diagnosis were followed for four and half years. Patients were randomly assigned to receive either Avonex or CinnoVex. Patients were subsequently visited every 6 months, and MRI was also undertaken prior each visit. The efficacy end points were to compare mean scores of expanded disability status scale (EDSS) and the proportion of patients with MRI and clinical activity in follow-up visits between Avonex and CinnoVex. Safety end point was to compare the percentage of adverse events between two groups. One hundred and eighty-two patients completed the study. The population of study experienced a steady increase in EDSS during follow-up with a mean increase of 1.03. Repeated measures ANOVA revealed no statistically significant difference between Avonex and CinnoVex (p = 0.78). The most common adverse events were headache, myalgia, fatigue, fever, flu symptoms, injection site pain, and depression. Direct comparison of each adverse events revealed no meaningful difference between two groups except for only a few adverse events. There was no statistically significant difference in MRI activity and clinical activity between two groups. Avonex and CinnoVex showed similar efficacy and safety outcome in patients with RRMS.