The safety and efficacy of stem cells for the treatment of severe community-acquired bacterial pneumonia: A randomized clinical trial.

Purpose: Evaluate the safety profile of expanded allogeneic adipose-derived mesenchymal stem cell (eASC) for the treatment of severe community-acquired bacterial pneumonia (CABP).
Materials and Methods: Randomized, multicenter, double-blind, placebo-controlled, phase 1b/2a trial. Patients with severe CABP were enrolled to receive intravenous infusions of Cx611 or placebo. The primary objective was safety including hypersensitivity reactions, thromboembolic events, and immunological responses to Cx611. The secondary endpoints included the clinical cure rate, ventilation-free days, and overall survival (Day 90).
Results: Eighty-three patients were randomized and received infusions (Cx611: n = 42]; placebo: n = 41]. The mean age was similar (Cx611: 61.1 [11.2] years; placebo: 63.4 [10.4] years). The number of AEs and treatment-emergent AEs were similar (243; 184 and 2; 1) in Cx611 and placebo respectively. Hypersensitivity reactions or thromboembolic events were similar (Cx611: n = 9; placebo: n = 12). Each study arm had similar anti-HLA antibody/DSA levels at Day 90. The clinical cure rate (Cx611: 86.7%; placebo: 93.8%), mean number of ventilator-free days (Cx611: 12.2 [10.29] days; placebo: 15.4 [10.75] days), and overall survival (Cx611: 71.5%; placebo: 77.0%) did not differ between study arms.
Conclusion: Cx611 was well tolerated in severe CABP. These data provide insights for future stem cell clinical study designs, endpoints and sample size calculation.
Trial Registration: NCT03158727 (retrospectively registered: May 09, 2017). Full study protocol: https://clinicaltrials.gov/ProvidedDocs/27/NCT03158727/Prot_000.pdf.
Competing Interests: Declaration of Competing Interest PFL has received honorarium from Takeda for blinded adjudication activities related to the SEPCELL trial and received consulting fees with Inotrem and Adrenomed. MSG has received honorarium from Takeda for blinded adjudication activities related to the SEPCELL trial. TvDP has received honorarium from Takeda for blinded adjudication activities related to the SEPCELL trial and received consulting fees from Pluristem outside the trial (both paid to Amsterdam UMC). XW was part of the clinical coordinating center located at Cliniques universitaires Saint-Luc, which assessed all patients' eligibility. FMS declares no conflict of interest. GH has received speaking fees and travel expenses from Fisher & Paykel Healthcare. RF has received consulting fees with Grifols, MSD, Pfizer, Shionogi, Gilead, Baxter, GSK, Menarini, and Boehringer outside the trial. JC has no conflict of interest. KAC and AS were salaried employees of Takeda Pharmaceuticals, Cambridge, MA, USA at the time of the study. BZ is a salaried employee of Takeda Pharmaceuticals, Cambridge, MA, USA. EL and OdlR are salaried employees of Takeda Madrid, Cell Therapy Technology Center, Tres Cantos, Spain. BF has received honorarium from Takeda for blinded adjudication activities related to the SEPCELL trial and consulting fees with Aridis, Enlivex, Inotrem, AM-Pharma, and GSK outside the trial.
(Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)