Sugemalimab Monotherapy for Patients With R/R Extranodal Natural Killer/T-Cell Lymphoma

GEMSTONE-201: A Single-Arm, Multicenter, Phase 2 Study 

Sugemalimab treatment was well-tolerated and demonstrated robust and durable antitumor activity among patients with relapsed/refractory (R/R) extranodal natural killer/T-cell lymphoma (ENKTL), according to a phase 2 study published in the Journal of Clinical Oncology.

R/R ENKTL is “a rare and aggressive type of non-Hodgkin lymphoma with limited treatment options,” wrote Huiqiang Huang, MD, Sun Yat-sen University Cancer Center, Guangzhou, China, and colleagues.

The GEMSTONE-201 study assessed the efficacy and safety of anti–PD-L1 monoclonal antibody sugemalimab for R/R ENKTL. Eligible patients received sugemalimab 1,200 mg intravenously once every 3 weeks for up to 24 months or until progression, death, or study withdrawal. The primary end point was objective response rate (ORR) assessed by an independent radiologic review committee. Key secondary end points included ORR assessed by the investigators, complete response rate, duration of response, and safety.

At the data cutoff of February 23, 2022, 80 patients were enrolled and followed for a median duration of 18.7 months. At baseline, 54 patients (67.5%) had stage IV disease and 39 (48.8%) had received ≥2 lines of prior systemic therapy. Independent radiologic review committee–assessed ORR was 44.9% (95% confidence interval [CI], 33.6 to 56.6) with 28 (35.9%) patients achieving a complete response and 7 (9.0%) achieving a partial response. The 12-month duration of response rate was 82.5% (95% CI, 62.0 to 92.6). Investigator-assessed ORR was 45.6% (95% CI, 34.3 to 57.2), with 24 (30.4%) patients achieving a complete response. Most treatment-emergent adverse events were grade 1 to 2 in severity, and grade ≥ 3 events were reported in 32 (40.0%) patients.

“Sugemalimab showed robust and durable antitumor activity in R/R ENKTL. Treatment was well-tolerated with expected safety profile for this drug class,” the study authors concluded. 

Source:

Huang H, Tao R, Hao S, et al. Sugemalimab monotherapy for patients with relapsed or refractory extranodal natural killer/T-cell lymphoma (GEMSTONE-201): Results from a single-arm, multicenter, phase II Study. J Clin Oncol. Published online March 30, 2023. doi: 10.1200/jco.22.02367