A multiple treatment comparison meta-analysis of monoamine oxidase type B inhibitors for Parkinson's disease

Aims
To the best of our knowledge, there are no systematic reviews or meta‐analyses that compare rasagiline, selegiline and safinamide. Therefore, we aimed to perform a drug class review comparing all available monoamine oxidase type B (MAO‐B) inhibitors in a multiple treatment comparison.

Methods
We performed a systematic literature search to identify randomized controlled trials assessing the efficacy of MAO‐B inhibitors in patients with Parkinson's disease. MAO‐B inhibitors were evaluated either as monotherapy or in combination with levodopa or dopamine agonists. Endpoints of interest were change in the Unified Parkinson's Disease Rating Scale (UPDRS) score and serious adverse events. We estimated the relative effect of each MAO‐B inhibitor versus the comparator drug by creating three networks of direct and indirect comparisons. For each of the networks, we considered a joint model.

Results
The systematic literature search and study selection process identified 27 publications eligible for our three network analyses. We found the relative effects of rasagiline, safinamide and selegiline treatment given alone and compared to placebo in a model without explanatory variables to be 1.560 (1.409, 1.734), 1.449 (0.873, 2.413) and 1.532 (1.337, 1.757) respectively. We also found all MAO‐B inhibitors to be efficient when given together with levodopa. When ranking the MAO‐B inhibitors given in combination with levodopa, selegiline was the most effective and rasagiline was the second best.

Conclusions
All of the included MAO‐B inhibitors were effective compared to placebo when given as monotherapy. Combination therapy with MAO‐B inhibitors and levodopa showed that all three MAO‐B inhibitors were effective compared to placebo, but selegiline was the most effective drug.