MeiraGTx Announces Positive Data from Randomized, Sham-controlled Clinical Bridging Study of AAV-GAD for the Treatment of Parkinson’s Disease

MeiraGTx
MeiraGTx

In This Article:

The primary study objective of safety and tolerability was met

Significant and clinically meaningful improvements from baseline demonstrated for key efficacy endpoints at 26 weeks

Significant improvement of 18 points in Unified Parkinson’s Disease Rating Scale (UPDRS) Part 3 in the high dose group at 26 weeks

Significant improvement in the Parkinson’s Disease Questionnaire (PDQ-39) score, a key quality of life measure, for both the high and low dose groups at 26 weeks

LONDON and NEW YORK, Oct. 15, 2024 (GLOBE NEWSWIRE) -- MeiraGTx Holdings plc (Nasdaq: MGTX), a vertically integrated, clinical-stage genetic medicines company, today announced top-line data from its clinical bridging study of AAV-GAD for the treatment of Parkinson’s disease, MGT-GAD-025.

MGT-GAD-025 is a 6-month, three-arm, randomized, double-blind, sham-controlled study using AAV-GAD drug product manufactured by MeiraGTx at its wholly-owned facilities with its commercial platform process. Participants had idiopathic Parkinson's disease, a history of levodopa responsiveness for at least 12 months, and a UPDRS Part 3 score of ≥25 points in the "off" state. Fourteen subjects were randomized to one of three groups (high dose n=5, low dose n=5, and sham n=4).

Subjects received either AAV-GAD infused bilaterally into the subthalamic nucleus or a sham procedure in a blinded fashion. The total dose per treated participant was 7.0×1010 vg (low dose group) or 21×1010 vg (high dose group). The primary objective of the study was to evaluate the safety and tolerability of AAV-GAD, with exploratory efficacy endpoints including the mean change from baseline to Week 26 in MDS-UPDRS Part 3 (motor examination) scores in the “off” state and the Parkinson’s Disease Questionnaire (PDQ-39) score, a key patient-reported quality of life measure in Parkinson’s disease. Subjects who completed this trial may enroll in a long-term follow-up study (NCT05894343), where they will be monitored for a total of five years post-treatment.

Top-line data summary:

  • AAV-GAD was safe and well tolerated, with no serious adverse events (SAEs) related to AAV-GAD treatment.

  • At Week 26, a statistically significant 18-point average improvement from baseline in UPDRS Part 3 “off” medication score was demonstrated in the high dose group (p=0.03), with no significant change in the sham or low dose groups.

  • Significant improvements from baseline in the disease-specific, patient-reported quality of life PDQ-39 score were demonstrated in both the high and low dose groups with no significant change in the sham group at Week 26:

    • In the high dose AAV-GAD group, the PDQ-39 score improved by 8 points from baseline (p=0.02), the low dose group improved by 6 points from baseline (p=0.04), while the 0.2 point worsening in the sham surgery group was not statistically significant.

    • A dose response in PDQ-39 score was observed, with 100% of participants in the high dose group, 60% of participants in the low dose group, and 25% of participants in the sham surgery group reporting an improvement.

    • For the PDQ-39 score, there was a trend to significance between the high dose and sham surgery groups at 6 months (n=4 evaluable per group).