2 results
Editor's Choice
Blood Adv. 2024 Mar 12;8(5):1105-1115 doi: 10.1182/bloodadvances.2023011625.
POPULATION:
Adults with haematological disorders, scheduled for allogeneic transplantation with a 9/10 or matched donor, and suitable for myeloablative conditioning, from a single centre in USA (n=24) INTERVENTION:An engineered graft product (T-reg) graft alone (n=12) COMPARISON:An engineered graft product (T-reg) graft plus single-agent GVHD prophylaxis (n=12) OUTCOME:All patients developed full donor myeloid chimerism. Patients with T-reg graft alone versus with prophylaxis had an incidence of grade II-IV acute GVHD of 58% versus 8% and grade III-IV of 17% versus 0%, respectively. The incidence of moderate to severe chronic GVHD was 28% in the T-reg graft alone arm versus 0% with prophylaxis. Among patients with T-reg graft and prophylaxis, CD4+ T cell:Treg ratios were reduced after transplantation, gene-expression profiles showed reduced CD4+ proliferation, and the achievement of full donor T cell chimerism was delayed. Allogeneic hematopoietic cell transplantation (HCT) is a curative therapy for hematological malignancies for which graft-versus-host disease (GVHD) remains a major complication. The use of donor T-regulatory cells (Tregs) to prevent GVHD appears promising, including in our previous evaluation of an engineered graft product (T-reg graft) consisting of the timed, sequential infusion of CD34+ hematopoietic stem cells and high-purity Tregs followed by conventional T cells. However, whether immunosuppressive prophylaxis can be removed from this protocol remains unclear. We report the results of the first stage of an open-label single-center phase 2 study (NCT01660607) investigating T-reg graft in myeloablative HCT of HLA-matched and 9/10-matched recipients. Twenty-four patients were randomized to receive T-reg graft alone (n = 12) or T-reg graft plus single-agent GVHD prophylaxis (n = 12) to determine whether T-reg graft alone was noninferior in preventing acute GVHD. All patients developed full-donor myeloid chimerism. Patients with T-reg graft alone vs with prophylaxis had incidences of grade 3 to 4 acute GVHD of 58% vs 8% (P = .005) and grade 3 to 4 of 17% vs 0% (P = .149), respectively. The incidence of moderate-to-severe chronic GVHD was 28% in the T-reg graft alone arm vs 0% with prophylaxis (P = .056). Among patients with T-reg graft and prophylaxis, CD4+ T-cell-to-Treg ratios were reduced after transplantation, gene expression profiles showed reduced CD4+ proliferation, and the achievement of full-donor T-cell chimerism was delayed. This study indicates that T-reg graft with single-agent tacrolimus is preferred over T-reg graft alone for the prevention of acute GVHD. This trial was registered at www.clinicaltrials.gov as #NCT01660607. |
|
|
Editor's Choice
Blood Cancer J. 2024 Feb 19;14(1):31 doi: 10.1038/s41408-024-00990-3.
POPULATION:
Adults with haematological malignancies undergoing transplant from a matched related or 10/10 HLA-matched unrelated donor with reduced intensity conditioning, recruited from eleven centres in France (n=89) INTERVENTION:Post-transplantation cyclophosphamide 50 mg/kg/d at days +3 and +4 plus standard GVHD prophylaxis (PTCy, n=44) COMPARISON:Anti-thymocyte globulin 5 mg/kg plus standard GVHD prophylaxis (ATG, n=45) OUTCOME:At 12 months, disease-free survival was 65.9% in the PTCy group and 67.6% in the ATG group. Cumulative incidence of relapse, non-relapse mortality, and overall survival were also comparable in the two groups. GRFS at 12 months was 54.5% in the PTCy group versus 43.2% in the ATG group. The median time to neutrophil and platelet count recovery was significantly longer in the PTCy group compared to the ATG group. Except for day +30, where EORTC QLQ-C30 scores were significantly lower in the PTCy compared to the ATG group, the evolution with time was not different between the two groups. The use of post-transplantation cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis is not established after reduced intensity conditioning (RIC) hematopoietic stem cell transplantation (HSCT) from fully matched donors. This was a randomized, open-label, multicenter, phase 2 trial. All patients received a RIC regimen with fludarabine, intravenous busulfan for 2 days (Flu-Bu2), and a peripheral blood stem cell (PBSC) graft from a matched related or 10/10 HLA-matched unrelated donor. Patients were randomly assigned to receive anti-thymocyte globulin (ATG) 5 mg/kg plus standard GVHD prophylaxis or PTCy 50 mg/kg/d at days +3 and +4 plus standard GVHD prophylaxis. The primary endpoint was the composite endpoint of GVHD- and relapse-free survival (GRFS) at 12 months after HSCT. Eighty-nine patients were randomly assigned to receive either PTCy or control prophylaxis with ATG. At 12 months, disease-free survival was 65.9% in the PTCy group and 67.6% in the ATG group (P = 0.99). Cumulative incidence of relapse, non-relapse mortality, and overall survival were also comparable in the two groups. GRFS at 12 months was 54.5% in the PTCy group versus 43.2% in the ATG group (P = 0.27). The median time to neutrophil and platelet count recovery was significantly longer in the PTCy group compared to the ATG group. Except for day +30, where EORTC QLQ-C30 scores were significantly lower in the PTCy compared to the ATG group, the evolution with time was not different between the two groups. Although the primary objective was not met, PTCy is effective for GVHD prophylaxis in patients receiving Flu-Bu2 conditioning with a PBSC graft from a fully matched donor and was well tolerated in term of adverse events and quality of life. This trial was registered at clinicaltrials.gov: NCT02876679. |