Study Rationale: Targeting neuroinflammation by increasing T regulatory cell numbers is a promising strategy for treating Parkinson’s disease. We propose a Phase 1 trial in non-PD volunteers for our novel clinical candidate, PDM608, which is a long-acting version of GM-CSF. GM-CSF has been shown to be safe in human patients with different diseases and effective in two groups of Parkinson’s disease patients.
Hypothesis: Given the highly favorable safety, pharmacokinetic and pharmacodynamic profiles demonstrated in our preclinical animal studies, along with the human safety profile of the related compound sargramostim, we hypothesize that our long-acting GM-CSF will be safe for human use and of benefit to Parkinson’s disease patients.
Study Design: We will enroll non-PD volunteers to evaluate safety, tolerability, pharmacokinetics and pharmacodynamics in a single center, randomized, double-blind, placebo-controlled study. Part 1 is a single ascending dose study consisting of 5 cohorts of 8 subjects each, while Part 2 is a multiple ascending dose study with 3 cohorts of 12 subjects each. We will study adverse events, pharmacokinetics, levels of anti-drug antibodies and pharmacodynamics in the study population.
Impact on Diagnosis/Treatment of Parkinson’s Disease: Following a successful Phase 1 study, efficacy in subsequent Phase 2 and Phase 3 clinical trials would offer a first-in-class disease-modifying treatment for Parkinson’s disease. Targeting neuroinflammation is a novel treatment approach that could reduce or halt the rate of disease progression.
Next Steps for Development: Positive results in this Phase 1 study would prompt us to proceed rapidly into Phase 2 clinical trials to test efficacy in Parkinson’s disease patients. The results from this study will inform decisions regarding appropriate dosing to ensure the best chances of efficacy as we plan the Phase 2 study.