Safety, immunological effects and clinical response in a phase I trial of umbilical cord mesenchymal stromal cells in patients with treatment refractory SLE

• Published in: Lupus science & medicine 2022-07, Vol.9 (1), p.e000704
• Main Authors: Kamen, Diane L, Wallace, Caroline, Li, Zihai, Wyatt, Megan, Paulos, Crystal, Wei, Chungwen, Wang, Hongjun, Wolf, Bethany J, Nietert, Paul J, Gilkeson, Gary
• Format: Article
• Language: English
• Subjects: Autoimmunity; B-Lymphocytes; Bone marrow; Clinical Trials and Drug Discovery; Disease; Immune system; Immunology; Lupus; Lupus Erythematosus, Systemic; Patients; Response rates
• ISSN: 2053-8790; 2053-8790
• DOI: 10.1136/lupus-2022-000704

BackgroundReports of clinical improvement following mesenchymal stromal cell (MSC) infusions in refractory lupus patients at a single centre in China led us to perform an explorative phase I trial of umbilical cord derived MSCs in patients refractory to 6 months of immunosuppressive therapy.MethodsSix women with a SLEDAI >6, having failed standard of care therapy, received one intravenous infusion of 1×106 MSCs/kg of body weight. They maintained their current immunosuppressives, but their physician was allowed to adjust corticosteroids initially for symptom management. The clinical endpoint was an SRI of 4 with no new British Isles Lupus Activity Guide (BILAG) As and no increase in Physician Global Assessment score of >0.3 with tapering of prednisone to 10 mg or less by 20 weeks.ResultsOf six patients, five (83.3%; 95% CI 35.9% to 99.6%) achieved the clinical endpoint of an SRI of 4. Adverse events were minimal. Mechanistic studies revealed significant reductions in CD27IgD double negative B cells, switched memory B cells and activated naïve B cells, with increased transitional B cells in the five patients who met the endpoint. There was a trend towards decreased autoantibody levels in specific patients. Two patients had increases in their Helios+Treg cells, but no other significant T cell changes were noted. GARP-TGFβ complexes were significantly increased following the MSC infusions. The B cell changes and the GARP-TGFβ increases significantly correlated with changes in SLEDAI scores.ConclusionThis phase 1 trial suggests that umbilical cord (UC) MSC infusions are very safe and may have efficacy in lupus. The B cell and GARP-TGFβ changes provide novel insight into mechanisms by which MSCs may impact disease.Trial registration numberNCT03171194.