Nilotinib In Patients With Advanced Parkinsons Disease: A Randomized Phase 2A Study (Nilo-Pd)

BackgroundNilotinib, a tyrosine kinase Abelson inhibitor, exhibits neuroprotective effects in preclinical Parkinson disease (PD) models. MethodsThis Phase 2A double-blind placebo-controlled study in moderate/advanced PD randomized participants 1:1:1 to placebo:150:300 mg nilotinib in matching capsules once daily for 6 months. The primary outcomes were safety and tolerability, the latter defined as ability to complete the study on assigned dose. Secondary outcomes included change in PD disability (Movement Disorder Society Unified Parkinsons Disease Rating Scale (MDS-UPDRS), Part 3 OFF/ON). Additional exploratory outcomes included serum and cerebrospinal fluid (CSF) pharmacokinetic (PK) profile, and CSF dopamine metabolites. FindingsThe study screened 125 and enrolled 76 participants (39% screen failure) between November 2017 and December 2018 at 25 US sites. The last participant completed the study in September 2019. At baseline, mean (standard deviation) age was 64.6 years (7.5), disease duration 9.9 years (4.7), MDS-UPDRS Part 1-3 OFF score 66.4(19.3) and ON score 48.4(16.2), Montreal Cognitive Assessment (MoCA) score 27.1(2.2). Tolerability was 21(84%):19 (76%):20 (77%) in placebo:150:300 mg arm, respectively. Both active doses were safe. The most common reasons for drug suspension were elevations of amylase and/or lipase, which were dose-dependent. The 300 mg group had transitory worsening of MDS-UPDRS-3 ON at 1 month compared to placebo (p<0.01), which resolved by 6 months. There was no difference in the change of MDS-UPDRS-3 OFF from baseline to 6 months between the groups (p=0.17). CSF/serum PK ratio was 0.2-0.3%. There was no evidence of treatment-related elevation of any dopamine metabolites. InterpretationBoth doses of nilotinib were safe and tolerable in these participants, who were selected with strict inclusion/exclusion criteria. There was no evidence of any symptomatic benefit of nilotinib. The drug had low CSF exposure and failed to change dopamine metabolites. These findings do not warrant further testing of nilotinib in PD. FundingThe study was funded by Funded by Michael J Fox Foundation for Parkinsons Research / The Cure Parkinson Trust / Van Andel Institute. Clinicaltrials.gov NCT03205488