Parkinson's disease drug therapies in the clinical trial pipeline: 2015–2024

Background There is an urgent need to find more effective treatments for motor and non-motor symptoms of Parkinson's disease (PD) and to ultimately discover therapies to slow, stop or reverse the condition. Objective To provide an overview of PD drug therapies in Phase 1–3 clinical trials between 2015–2024 in order to highlight research findings and trends, identify opportunities for further research and funding, and provide a common ground for discussion among the patient, research and funding communities. Methods A dataset of PD drug clinical trials registered on ClinicalTrials.gov between 2015–2024 was analyzed and classified by trial focus (symptomatic therapy or disease-modifying therapy), trial phase, therapeutic category and drug novelty. Results The dataset included 444 trials, of which 42% were in Phase 1, 46% in Phase 2 and 12% in Phase 3. 63% of the trials were evaluating symptomatic therapies (ST) and 37% were testing disease-modifying therapies (DMT). 52% of the trials were exploring novel treatments, a third were testing repurposed compounds and the remainder were evaluating reformulations of existing PD drugs. 281 drug interventions were evaluated across the 444 trials. Conclusion The pipeline of clinical trials evaluating PD drug therapies between 2015–2024 contained a diverse set of novel, repurposed and reformulated compounds across a variety of biological pathways. While additional symptomatic treatments received regulatory approval, there are still no treatments to modify the course of the disease.