Monoamine oxidase type B (MAO-B) inhibitors have shown neuroprotective effects in cell culture and animal studies of Parkinson’s disease (PD), but clinical trial results have been mixed and have failed to convincingly demonstrate disease modifying effects. However, data published in the Journal of Parkinson’s Disease , show that extended treatment with an MOA-B inhibitor slowed clinical decline in PD patients.
The finding is based on a secondary analysis of data from the NET-PD-LS1 clinical trial; a multicentre, double-blind, placebo-controlled trial of 1,741 participants with early PD to determine whether creatine mono-hydrate 10mg/day is more effective than placebo in slowing long-term clinical decline. NET-PD-LS1 is one of the largest and longest PD clinical trials to date.
During that study, approximately half of participants received an MAO-B inhibitor. After adjusting for identifiable confounding factors, a significant association was identified between longer duration of MAO-B inhibitor exposure and slower clinical decline. A one-year increase in duration of MAO-B inhibitor exposure was associated with a benefit equivalent to approximately 20% of the annual decline in activities of daily living, ambulatory capacity, and global disability observed in participants not receiving an MAO-B inhibitor. The results suggest MAO-B inhibitors may confer long-term benefits in PD.