Donor-derived Anti-CD19 CAR T cells GC007g for relapsed or refractory B-cell acute lymphoblastic leukemia after allogeneic HSCT: a phase 1 trial.

Background: Although chimeric antigen receptor-modified T cells (CAR T) cell therapy has been widely reported in improving the outcomes of B-cell acute lymphoblastic leukemia (B-ALL), less research about the feasibility and safety of donor-derived CAR T after allogeneic hematopoietic stem cell transplantation (allo-HSCT) was reported. Methods: This phase 1 clinical trial aims to evaluate safety and efficacy of donor-derived anti-CD19 CAR T cells (GC007g) in B-ALL patients who relapsed after allo-HSCT. This trial is registered with ClinicalTrials.gov, NCT04516551. Findings: Between 15 March 2021 and 19 May 2022, fifteen patients were screened, three patients were excluded due to withdraw of consent, donor's reason, and death, respectively. Patients received donor-derived CAR T cells infusions at 6 × 105/kg (n = 3) or 2 × 106/kg (n = 6) dose level. The median time from HSCT to relapse was 185 days (range, 81-2063). The median age of patients was 31 years (range 21-48). Seven patients (77.8%) had BCR-ABL fusion gene. CAR T cells expanded in vivo and the median time to reach Cmax was 9 days (range, 7-11). One patient had hyperbilirubinemia after GC007g infusion which was defined as a dose-limiting toxicity. All patients experienced CRS and hematological adverse events. Three patients had acute graft-versus-host-disease (grade I, n = 1; grade II, n = 1; grade IV, n = 1) and all resolved after treatment. They received CAR T cells from matched sister, haploidentical matched father and sisiter, respectively. At 28 days after infusion, all patients achieved complete remission with/without incomplete hematologic recovery (CRi/CR) with undetectable MRD. At a median follow-up of 475 days (range 322-732), seven patients remained in CR/CRi while two had CD19-negative relapse. The overall response rates (ORR) were 100% (9/9), 88.9% (8/9), and 75% (6/8) at 3 month, 6 month, and 12 month, respectively. The 1-year progression-free and overall survival were 77.8% and 85.7%, respectively. Interpretation: GC007g expanded and induced durable remission in patients with B-ALL relapsed after allo-HSCT, with manageable safety profiles. Funding: Gracell Biotechnologies Inc.

Efficiency and Toxicity of Imatinib Mesylate combined with Atorvastatin Calcium in the Treatment of Steroid-Refractory Chronic Graft-Versus-Host Disease: A Single-center, Prospective, Single-arm, Open-label study.

INTRODUCTION: Steroid-refractory cGVHD (SR-cGVHD) presents new great challenges for treatment. We have reported imatinib monotherapy was effective to SR-cGVHD, but the CR rate was not satisfactory and the benefit was not showed specific to some target organs, previously. Imatinib and statin drugs have been recognized to regulate T-cell function, statins also have been demonstrated endothelia protection, but whether this combination therapy was able to improve the efficacy remains unknown. Therefore, we designed this prospective, single-arm, open-label trial to investigate the efficacy of imatinib-based combination therapy in the treatment of SR-cGVHD for the first time. METHODS: 60 SR-cGVHD patients were entered into this trial to investigated the combination of imatinib mesylate and atorvastatin calcium for the treatment of SR-cGVHD. The primary endpoint included the overall response rate (ORR) after 6 months of combined treatment. The secondary endpoints included an evaluation of survival, changes in T-cell subsets and adverse events. RESULTS: At baseline, 45% (27/60) of patients had moderate cGVHD, and 55.0% (33/60) of patients had severe cGVHD. At the 6-month follow-up, a clinical response was achieved in 70.0% of patients, and a complete response (CR) was achieved in 26.7%. A total of 11.7% (7/60) of patients stopped immunosuppressive therapy at this point. After 6 months of treatment, the ORR rates of the liver, skin, eyes and oral cavity were 80.6%, 78.1%, 61.5%, and 60.9%, respectively, with the liver also having the highest CR of 58.1%. The patients with moderate cGVHD had a better CR rate than those with severe cGVHD (55.6% vs. 3.0%, P<0.0001). The overall survival in patients who with ORR was improved (P = 0.0106). Lung involvement is an independent risk factor to affected ORR achievement (P = 0.021, HR = 0.335, 95%CI 0.133-0.847), and the dosage of steroids was reduced in ORR patients. In clinical response patients, the ratio of CD8+ T cells (P = 0.0117) and Th17 cells (P = 0.0171) decreased, while the number of Treg cells (P = 0.0147) increased after 3 months. The most common adverse events were edema, nausea, and neutropenia which were 13.3%, 11.7%, and 11.7%, respectively. CONCLUSION: Combination treatment with imatinib mesylate and atorvastatin calcium was effective in treating SR-cGVHD and significantly decreased target organ injury, especially liver damage, indicating that T-cell regulatory function may play an important role in this process.

Outcomes of patients with hematological malignancies who undergo unrelated donor hematopoietic stem cell transplantation with ATG-Fresenius versus ATG-Genzyme.

To compare the outcomes of patients with hematological malignancies who received ATG-Fresenius (ATG-F) 20 mg/kg versus those who received ATG-Genzyme (ATG-G) 10 mg/kg in an unrelated donor hematopoietic stem cell transplantation (HSCT) procedure, a total of 186 patients who underwent their first allogeneic HSCT with an unrelated donor were retrospectively analyzed. One hundred and seven patients received ATG-F, and seventy-nine patients received ATG-G. Multivariate analysis showed that the type of ATG preparation had no effect on neutrophil engraftment (P = 0.61), cumulative incidence of relapse (P = 0.092), nonrelapse mortality (P = 0.44), grade II-IV acute graft-versus-host disease (GVHD) (P = 0.47), chronic GVHD (P = 0.29), overall survival (P = 0.795), recurrence-free survival (P = 0.945) or GVHD-free relapse-free survival (P = 0.082). ATG-G was associated with a lower risk of extensive chronic GVHD and a higher risk of cytomegaloviremia (P = 0.01 and HR = 0.41, P < 0.001 and HR = 4.244, respectively). The results of this study suggest that the preparation of rabbit ATG used for unrelated HSCT should be selected based on the incidence of extensive chronic GVHD of each center, and the posttransplant management strategy should be adjusted according to the ATG preparation.

Analysis of the Efficacy and Safety of Avatrombopag Combined With MSCs for the Treatment of Thrombocytopenia After Allogeneic Hematopoietic Stem Cell Transplantation.

Platelet graft failure (PGF) is a frequent and serious complication after Allogeneic hematopoietic stem cell transplantation (allo-HSCT) and lacks effective treatment strategies, which could affect the prognosis of patients and even cause death. The exact underlying mechanism of PGF remains unclear, and lacks standard treatment. Here, we conduct a retrospective study to evaluate the efficacy and safety of avatrombopag combined with mesenchymal stem cells (MSCs) in 16 patients with thrombocytopenia after allo-HSCT. Patients were administered the following treatment regimen: 20 mg/d avatrombopag; if the PLT count was less than 50×10^9/L for at least 2 weeks, the dose was increased to 40 mg/d; if the PLT count was 200-400×10^9/L, the dose was reduced; and if the PLT count was greater than 400×10^9/L, avatrombopag was terminated. Umbilical cord MSCs (1×10^6 cells/kg) infusion was performed every week for 4-6 weeks. Among the 16 patients, 13 patients (81.3%) achieved a complete response (CR), 2 patients (12.5%) got a partial response (PR), and 1 patient (6.3%) had no response (NR). The median time to obtain CR was 32 (7-426) days after treatment with avatrombopag combined with umbilical cord MSCs. The time to reach 20×10^9/L≤ PLT <50×10^9/L in the 2 patients with PR was 52 and 230 days after treatment, respectively. One patient had a severe pulmonary infection and died of cytomegalovirus pneumonia. Overall, our results indicated that combination of avatrombopag with MSCs can promote platelet recovery after transplantation, thereby improving the survival rate of patients and improving the quality of life of patients after transplantation, and providing a new method and strategy for the treatment of thrombocytopenia after allo-HSCT.