Barriers against a successful MS treatment: The importance of effectiveness beyond efficacy

Current multiple sclerosis (MS) therapeutic options have significantly increased treatment algorithm complexity. This urges physicians to take into account multiple factors in the decision-making process and make an even more thorough analysis of the risk-benefit balance. We carried out a descriptive review aiming to assess some factors that endanger the proper MS treatment fulfillment, focusing mainly on Latin American countries. Firstly, it is paramount to warrant the correct, fair and timely treatment access. We found that disease modifying drugs (DMDs) access is highly variable among different countries and even different regions within a country. In this sense less than 35% of MS patients in Latin American have access to treatment. Secondly, adherence depends on some characteristics such as the way of administration, treatment length and side effects, among others. Finally, chronic immune suppression has become a common consequence of most DMDs. Hence, the different mechanisms of action and their safety profile should be taken carefully into consideration when choosing a specific drug. These three areas of interest related to a single medication, adherence, access to it and mechanism of action, are of utmost importance when trying to achieve effectiveness instead of just efficacy.