[PD-1 Inhibitor Combined with Azacitidine and HAG Regimen for the Treatment of Relapsed/Refractory Acute Myeloid Leukemia: A Prospective, Single-Arm, Phase II Clinical Study].

To evaluate the efficacy and safety of PD-1 inhibitor combined with azacitidine and HAG regimen in the treatment of relapsed/refractory acute myeloid leukemia (R/R AML). This study is a prospective, single-arm, phase II clinical trial that included R/R AML patients who met the inclusion criteria and were treated at The First Affiliated Hospital of Soochow University from December 2020 to August 2023. Patients could undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT) after salvage therapy. The efficacy and safety were evaluated. Twenty patients were enrolled, including 14 males and 6 females, with an average age of (50.7±15.3) years. The overall response rate (ORR) after one cycle of the treatment was 75.0% (15/20), and 35.0% (7/20) of the patients achieved complete remission (CR) or complete remission with incomplete hematologic recovery (CRi) after two cycles of the treatment. Eight patients received allo-HSCT. The main adverse events were hematologic toxicities, and no grade 5 adverse events occurred. The combination of PD-1 inhibitor, azacitidine, and the HAG regimen is a feasible and relatively safe treatment option for R/R AML, thus, to be worth further study.