Safety and preliminary efficacy of allogeneic bone marrow-derived multipotent mesenchymal stromal cells for systemic sclerosis: a single-centre, open-label, dose-escalation, proof-of-concept, phase 1/2 study.

BACKGROUND: Systemic sclerosis remains an orphan life-threatening autoimmune disease. The unique immunomodulatory, proangiogenic, and antifibrotic properties of mesenchymal stromal cells provide a strong rationale for mesenchymal stromal cell-based therapy for systemic sclerosis, and treatment with mesenchymal stromal cells has shown benefits in preclinical models of this disease. The safety of allogeneic bone marrow-derived mesenchymal stromal cell administration in patients with severe systemic sclerosis has not yet been established. We aimed to test the safety and feasibility of a single intravenous injection of intrafamilial allogeneic bone marrow-derived mesenchymal stromal cells to treat severe diffuse systemic sclerosis. METHODS: We did an open-label, dose-escalation, proof-of-concept, phase 1/2 study at Saint-Louis-Hospital, Paris, France. Eligible patients were aged 18-70 years with severe diffuse systemic sclerosis, who fulfilled the 2013 American College of Rheumatology and European League Against Rheumatism systemic sclerosis criteria, had a minimum modified Rodnan skin score of 15 (range 0-51), had severe lung, heart, or kidney involvement, and had inadequate response or contraindications to conventional immunosuppressive therapy or autologous haematopoietic stem cell transplantation. Patients with severe comorbidities were excluded. The first ten recipients were to receive a single intravenous infusion of 1 × 106 bone marrow-derived mesenchymal stromal cells per kg bodyweight, and the subsequent ten recipients were to be infused with a single dose of 3 × 106 bone marrow-derived mesenchymal stromal cells per kg bodyweight. The primary endpoint was immediate tolerance during infusion and within the first 10 days after infusion, measured as the occurrence of serious adverse events (grade 3 or higher) in all infused patients. Safety was assessed in all participants during the 24-month follow-up period. This study is registered with ClinicalTrials.gov, NCT02213705. FINDINGS: Between March 24, 2014, and Jan 6, 2020, 20 cisgender individuals (13 women and seven men) with severe diffuse systemic sclerosis were enrolled. All 20 patients were included in the primary outcome analysis. No infusion-related severe adverse events and three infusion-related adverse events occurred in the first 10 days after treatment; one patient had grade 1 flushing and another patient had grade 1 nausea and grade 2 asthenia. After ten days and up to a median follow-up of 24·1 months (IQR 20·8-24·5), 36 non-treatment-related severe adverse events in 14 (70%) patients and no treatment-related adverse event were reported. INTERPRETATION: A single infusion of allogeneic bone marrow-derived mesenchymal stromal cells was safe in patients with severe diffuse systemic sclerosis. Future placebo-controlled trials will help to definitively ascertain the efficacy of mesenchymal stromal cell-based cell therapy from various tissue sources in larger number of patients with systemic sclerosis. FUNDING: French Ministry of Health, Capucine Association, Fonds de Dotation de l'AFER pour la Recherche Médicale, and Agence Nationale de la Recherche (Infrastructure Program Ecell), France.

Long term outcomes of the French ASTIS systemic sclerosis cohort using the global rank composite score.

Two randomised trials (ASTIS, SCOT) of Autologous Hematopoietic Stem Cell Transplantation (AHSCT) versus monthly Cyclophosphamide for severe Systemic Sclerosis (SSc) patients used similar inclusion criteria, but different primary endpoints: event-free-survival (EFS) at 24 months in ASTIS versus the global rank composite score (GRCS) at 54 months in SCOT. Here we analysed the French ASTIS cohort (n = 49) outcome using the same GRCS endpoint as reported in SCOT. All patients, randomised to AHSCT (n = 26) or Cyclophosphamide (n = 23), were evaluated for the non-parametric GRCS endpoint based on: death, EFS, forced vital capacity (FVC), Health Assessment Questionnaire Disability Index (HAQ-DI) and modified Rodnan skin score (mRSS) at 60 months. Secondary endpoints were: EFS, overall survival (OS), HAQ DI and organ status. In intention-to-treat analysis, the GRCS demonstrated superiority for AHSCT (median: 9 versus -19, p = 0.018), mRSS (Δ mRSS: -16 versus -9, p = 0.02), and HAQ-DI (ΔHAQ-DI: -0.89 versus -0.2, p = 0.05) with no significant difference in OS, EFS, lung, heart and kidney function between the groups. In conclusion, this study demonstrates long term benefits of non-myeloablative AHSCT when assessed by the five longitudinal measures within GRCS affording direct primary endpoint comparison between ASTIS and SCOT.

Association of Autologous Hematopoietic Stem Cell Transplantation in Systemic Sclerosis With Marked Improvement in Health-Related Quality of Life.

OBJECTIVE: To quantify the magnitude, domains, and duration of change in health-related quality of life (HRQoL) in patients with systemic sclerosis (SSc) who underwent autologous hematopoietic stem cell transplantation (HSCT) as compared to SSc patients with similar characteristics who did not undergo autologous HSCT. METHODS: The study was designed as a retrospective study comparing SSc patients who underwent autologous HSCT and SSc patients who met the criteria for transplantation but were treated with conventional care. Outcomes included scores on the 36-item Short Form (SF-36) health survey and the Health Assessment Questionnaire (HAQ) and its disease-specific symptom scales. Differences in scores between the groups were compared using linear models, adjusting for baseline scores and inverse probability of treatment and censoring weights. RESULTS: In total, 41 SSc patients who underwent autologous HSCT and 65 SSc patients treated with conventional care were compared. In marginal linear weighted models, the SF-36 physical component summary score was a mean ± SEM 7.02 ± 1.94 points higher at the first annual visit (P = 0.001) and 14.40 ± 6.16 points higher at the seventh annual visit (P = 0.03) in patients treated with autologous HSCT compared to the conventional care group. HAQ scores were significantly better in the autologous HSCT group compared to the conventional care group during follow-up (mean ± SEM difference from baseline -0.57 ± 0.13 [P < 0.001] at the first annual visit and -0.94 ± 0.49 [P = 0.07] at the seventh annual visit). There were no differences in the SF-36 mental component summary scores between the 2 groups either at baseline or during follow-up. CONCLUSION: This study provides robust complementary HRQoL data, including overall and event-free survival data, to expand on the standard repertoire of biomedical variables, thus potentially supporting the physical benefits of autologous HSCT in patients with SSc.