A pilot phase IIa randomized, placebo-controlled, double-blind trial of intravenous human pluripotent adipose-derived stem cells (PASCs) in Parkinson's disease: The REPOSE study.

Pluripotent adipose-derived stem cells (PASCs) are a non-tumorigenic, stress-enduring SSEA-3+ cell population sharing key biological markers with Muse cells while representing a phenotypically distinct population. This Phase IIa randomized, double-blind, placebo-controlled pilot trial evaluated the safety, feasibility, and exploratory clinical effects of intravenous PASCs in Parkinson's disease (PD). Forty participants with Hoehn and Yahr stages I-III PD were randomized 1:1 to receive three intravenous infusions of PASCs (25 million cells) or placebo at baseline, month 3, and month 6, with 12-month follow-up. All participants underwent a structured neurological rehabilitation program. The primary endpoint was safety (CTCAE v5.0). No treatment-related adverse events of any grade were observed across 60 infusions. One thromboembolic event in the PASC group was independently adjudicated as of uncertain relationship to the study intervention, and one death in the placebo group was adjudicated as unrelated. For each of the seven exploratory functional and quality-of-life endpoints, the global treatment-by-time interaction was tested and adjusted for multiplicity using the Benjamini-Hochberg procedure; no endpoint reached significance after control of the false discovery rate (all q > 0.05). Repeated intravenous PASC administration is safe and feasible in PD. Efficacy was not demonstrated in this pilot trial, and the exploratory findings are hypothesis-generating, supporting further investigation in adequately powered Phase IIb/III trials.