Mei Q, et al. Clin Cancer Res 2020.
PURPOSE: Patients with relapsed/refractory primary mediastinal B-cell lymphoma (rrPMBCL) represent a particularly challenging population to treat, with few life-saving treatment options in the context of a dismal prognosis.
EXPERIMENTAL DESIGN: In this open-label, single-arm, phase 2 study, the safety and efficacy of combined regimen of chemotherapy consisting of gemcitabine, vinorelbine and pegylated liposomal doxorubicin (GVD) plus anti-PD-1 antibody camrelizumab was assessed in rrPMBCL. Patients received chemo-immunotherapy every 3 weeks until the second confirmed complete response or up to 12 cycles, followed by camrelizumab monotherapy for up to 1 year. The primary endpoints were objective response rate and safety.
RESULTS: 27 response-evaluable patients were enrolled, who received a median of 3 frontline therapies, 59% with bulky disease. The objective response rate was 74%, including 56% with a complete response. A median time of 1.7 months to response was observed, with 78% exhibiting tumor shrinkage at the first evaluation. After 24.8 months median follow-up, the median duration of response was not reached, with a 65% 2-year estimated response rate. Thirteen responders remained in sustained complete remission. Estimated 24-M progression-free survival and overall survival rates were 48.2% and 81.5%, respectively. Any-grade and grade 3 treatment-related adverse events occurred in 93% and 33% of patients, respectively; with no grade 4 or 5 adverse events. Baseline levels of IL-10, IFN-γ and sFas were associated with objective response.
CONCLUSIONS: Camrelizumab plus GVD chemotherapy offers a potent option as life-saving chemo-immunotherapy with promising efficacy and a manageable safety profile for rrPMBCL patients, especially with bulky aggressive disease.