Should We Use Combination Therapy for Multiple Sclerosis?

By Susan Gauthier, DO, MS, Assistant Professor of Neurology, Weill Cornell Medical College.

Synopsis: This study finds that combined treatment of interferon beta 1a and glatiramer acetate is not more effective than either individual treatment in combating relapsing-remitting multiple sclerosis.

Source: Lublin F, et al. Randomized study combining interferon and glatiramer acetate in multiple sclerosis. Ann Neurol 2013;73:327-340.

The injectables interferon beta and glatiramer acetate (GA) have in recent years been joined by a multitude of other FDA-approved multiple sclerosis treatments. Each injectable treatment is considered only partially effective as ensuring patient cooperation has repeatedly proved difficult. As such, considerably more convenient oral treatment agents have entered the scene bringing a wide range of efficacy. Despite compliance issues, injection therapy to treat MS consistently has demonstrated the most desirable safety profiles. This increases the importance of improving injection therapy’s efficacy, leading to the conduction of the current CombiRx study, which expected to improve injectable MS treatments by combining interferon beta 1a with glatiramer acetate treatment.

Randomized and double-blind, the CombiRx study matched patients treated with a combined IFN/GA treatment or individual treatment alone with a matching placebo. The study initially intended to last 3 years but some patients participated for up to seven years as a part of an extended phase. In order to be included, patients had to have experienced at least two MS relapses in the prior 36 months. The outcome measure that was prioritized was the rate of annual relapse. Other, secondary outcome measures included changes in clinical disability scores as well as composite MRI scores. The study aimed to compare the combination treatment to the more effective of the two individual treatments, which proved to be glatiramer acetate. In comparisons, the combination group proved to not be more effective than GA treatment alone. None of the groups showed significant differences in disease progression, composite MRI or brain atrophy rates. The combination treatment of IFN and GA, however, did show significantly better results in lessening the number of enhancing lesions as well as in disease activity-free status, suggesting that though the study found no significant proof that combination therapy is more effective, the method merits further research.