A larger proportion of patients achieved a ≥5-point improvement in motor function with three infusions of allo-hMSCs compared to placebo (93.7% probability).
The mean improvement in motor function for the three-infusion group was 16.9 points on the scale, while the placebo group improved by 14.6 points.
Fewer patients in the two-infusion group showed significant improvement compared to placebo, with a mean improvement of only 3.9 points.
All treatment arms exhibited some level of improvement in motor function on the MDS-UPDRS-III scale.
Adverse events reported were mild and transient, indicating a favorable safety profile for the allo-hMSC infusions.
Future studies are needed to explore the variability in clinical efficacy related to different batches of allo-hMSCs.
Simplified
BACKGROUND: Neuroinflammation contributes to Parkinson's disease (PD) progression and motor dysfunction. Allogeneic human mesenchymal stem cells (allo-hMSCs) may reduce neuroinflammation and improve motor symptoms.
OBJECTIVES: To evaluate the efficacy of repeated intravenous doses of 10 × 10/kg allo-hMSCs in improving motor symptoms in patients with PD (PwP). 6
METHODS: In this phase 2, randomized, placebo-controlled trial (November 2020-July 2023), mild-to-moderate PwP received either three allo-hMSC infusions, one placebo followed by two allo-hMSC infusions, or three placebo infusions at 18-week intervals. Follow-up lasted 88 weeks. The primary outcome was a >70% posterior probability (PP) of a difference in the proportion of participants with ≥5-point improvement in OFF-medication Movement Disorder Society Sponsored Revision of the Unified Parkinson's Disease Rating Scale-Part III () at week 62. Bayesian analysis was conducted using R v4.2.0.
RESULTS: Forty-five PwP were enrolled. A larger proportion of subjects achieved a ≥5-point improvement in MDS-UPDRS-III in the three-infusion arm compared with placebo at week 62 (mean difference [MD]: 5.0%, PP = 93.7%), translating to a 16.9-point improvement in MDS-UPDRS-III in the three-infusion arm compared with a 14.6-point improvement in the placebo arm. Conversely, fewer subjects in the two-infusion arm compared with placebo showed ≥5-point improvement at week 62 (MD: -62.4%, PP ≥ 99.9%), translating to only a 3.9-point improvement in MDS-UPDRS-III in the two-infusion arm. However, improvement in MDS-UPDRS-III was seen across all treatment arms. Adverse events were mild and transient.
