Safety and Tolerability of ADR-001 Therapy for Immunoglobulin A Nephropathy.

Background: Immunoglobulin A nephropathy often requires kidney replacement therapy because of its refractoriness and because corticosteroids pose infection risks. However, mesenchymal stem cells offer clinical benefits because of their regenerative and immunomodulatory properties. This prospective clinical trial assessed the safety and tolerability of adipose-derived mesenchymal stem cell therapy and evaluated its therapeutic efficacy.

Methods: This phase 1 study included adult patients with refractory immunoglobulin A nephropathy that was difficult to treat with traditional therapies. Adipose-derived mesenchymal stem cell therapy comprising one intravenous dose of 1 × 108 cells was administered to three to six patients in cohort 1. The same intravenous dose was administered twice with a 2-week interval to six patients in cohort 2. Heparin was administered simultaneously. This study continued for 52 weeks, and the primary endpoints were safety and tolerability during the 6-week period after treatment administration. Secondary endpoints included adverse events and efficacy measures such as clinical remission, partial remission, urine protein remission, hematuria remission, time to remission, changes in the urine protein and hematuria levels, and changes in the estimated glomerular filtration rate.

Results: The three patients in cohort 1 and six patients in cohort 2 who received adipose-derived mesenchymal stem cell therapy achieved the primary endpoints. No severe adverse clinical events were observed. Therefore, the safety and tolerability of adipose-derived mesenchymal stem cells were confirmed. Improvements such as significantly decreased kidney damage markers and urinary protein levels were observed immediately after adipose-derived mesenchymal stem cell administration.

Conclusions: The safety and tolerability of adipose-derived mesenchymal stem cells are acceptable for patients with immunoglobulin A nephropathy.

Trial registration: This trial was registered with the Japan Registry of Clinical Trials (jRCT2043200002; registration date: April 14, 2020) and ClinicalTrials.gov (NCT04342325; registration date: April 13, 2020).