4D Molecular presents interim data from 4D-310 INGLAXA Phase 1/2 trials

4D Molecular Therapeutics announced updated interim safety and efficacy data on six adults with Fabry disease cardiomyopathy treated with a single intravenous infusion of 4D-310 with follow-up of 12-33 months overall, including 12-24 month follow-up data on cardiac contractility, exercise capacity, quality of life and cardiac biopsy data. The data was presented in a late-breaking session at WORLDSymposium 2024 in San Diego, California on Friday, February 9, 2024. INGLAXA Phase 1/2 Clinical Trial Design & Enrollment: Dose escalation and dose expansion trial assessing a single IV infusion of 4D-310 in a broad and diverse Fabry disease patient population; Enrolled six patients, each treated with 1E13 vg/kg of 4D-310 and a prophylactic corticosteroid immunosuppressive regimen; Protocol amended to change immunosuppressive regimen to rituximab and sirolimus; Cardiac biopsies allowed at week 6 and 26 in the INGLAXA-2 trial. INGLAXA Phase 1/2 Interim Data Summary: Safety and Tolerability: Previously reported cases of aHUS have fully resolved; No clinically significant cardiac or liver toxicities; No new 4D-310-related adverse events greater than Grade 1 since the last interim update in February 2023. Echocardiography Contractility Assessments: Improved GLS in all five evaluable patients by month 12; Two patients who reached 24 months of follow-up both showed clinically meaningful improvement with change from baseline exceeding the minimal detectable difference of -1.5%. Cardiopulmonary Exercise Testing Peak VO2 Assessments: 3 of 4 evaluable patients demonstrated clinically meaningful improvement by CPET peak VO2 with change from baseline exceeding the minimal clinically important difference of +1.5 at month 12; One patient who reached 24 months of follow up continued to show meaningful improvement with change from baseline exceeding the MCID of +1.5. Cardiac Quality of Life Assessments; Two patients had low baseline scores less than90; both patients had clinically meaningful improvements in QOL; Cardiac Biopsy Assessments of Transgene Expression and Substrate Clearance; Cardiac biopsies at week 6 and 26 from one patient showed robust & durable 4D-310-mediated transgene expression in cardiomyocytes: At week 26, mean Gb3 inclusion body volume per cardiomyocyte was reduced 15% from week 6 and 61% vs. historical sample collected approximately 7 years prior to enrollment and analyzed independently by investigator.