Comparative effectiveness of tislelizumab versus pembrolizumab as monotherapy in transplant-ineligible adult relapsed/refractory classical Hodgkin lymphoma: a systematic review

Abstract

Pembrolizumab is a widely accepted PD-1 inhibitor in relapsed/refractory classical Hodgkin lymphoma (R/R cHL). It can be used in conjunction with hematologic stem cell transplant (HSCT), either as induction or as salvage therapy after HSCT. However, HSCT is not widely available in Indonesia. Nevertheless, pembrolizumab as a single agent is still recommended for patients ineligible for HSCT. Tislelizumab, a novel PD-1 inhibitor, has emerged as a potential alternative with promising results. We aimed to compare both regimens in managing R/R cHL, especially in ASCT-ineligible settings. A systematic literature search identified 128 articles. After the exclusion process, including studies involving HSCT after PD-1 treatment, 2 prospective phase II clinical trials were analyzed. Eligible studies evaluated adult R/R cHL patients who were previously treated by 2 or more chemotherapy lines and had not received HSCT. Outcomes assessed included overall response rate (ORR), complete response rate (CRR), progression-free survival (PFS), and treatment-related adverse events (AEs). Tislelizumab achieved an ORR of 87.1%, CRR of 67.1%, and median PFS of 31.5 months, with grade ≥3 AEs in 31.4% of patients. Pembrolizumab demonstrated an ORR of 66.7%, CRR of 25.9%, and median PFS of 13.2 months, with a lower incidence of grade ≥3 AEs (12–16%). Both studies showed a moderate risk of bias. As no head-to-head clinical trials have been conducted between these regimens in this specific patient population, this limits a definitive conclusion. Treatment decisions should balance response depth, safety, and strength of supporting evidence. Further head-to-head studies are needed to guide optimal therapy selection