Newly approved agents for relapsing remitting multiple sclerosis: how real-world evidence compares with randomized clinical trials?

From the authors' review of the literature, the efficacy profiles resulted from RCTs were confirmed by observational studies with regard to the disease-modifying drugs considered. The magnitude of the effects on annualized relapse rates and MRI active lesions was generally even larger in the observational studies compared to RCTs. From the safety point of view, observational studies revealed new adverse events, mostly in the area of bacterial and opportunistic infections, not seen in the relative registration programme. This is a very important gain because it allows to elaborate appropriate strategies to prevent and handle the risks.