When considering combination therapy with MAO-B inhibitors and levodopa, all three were effective compared to placebo, but selegiline was the most effective, and remained the most effective when adjusting for disease duration (2.410; 1.874-3.105).
The authors defined responders as the number of patients with at least 20% reduction in the UPDRS scores, or an improvement on the Clinical Global Impressions (CGI) scale from baseline to end of study. They note however that it is uncertain how much clinical difference these changes make for the individual patient. Although the CGI scale and the Activities of Daily Living (ADL) part II of the UPDRS takes this into consideration, these were not included as part of the outcome measure in all of the included studies. No study has directly compared all of the monoamine oxidase B (MAO‑B) inhibitors.
The NICE guideline on Parkinson’s disease, published in July 2017, does not distinguish between the available MAO-B inhibitors in its recommendations.