Zimberelimab

Overview

Zimberelimab (WBP-3055, GLS-010, AB122) is a fully human monoclonal antibody targeting programmed cell death protein 1 (PD-1). It is being studied alone and in combination regimens across multiple cancers. It received its first approval in China in 2021 for relapsed or refractory classical Hodgkin lymphoma (cHL) after at least two prior systemic therapies; development in other indications remains investigational. (pubmed.ncbi.nlm.nih.gov)

Mechanism of action

Zimberelimab is an IgG4 antibody that binds PD-1 and blocks signaling through its ligands, PD-L1 and PD-L2. This releases an inhibitory immune checkpoint and can restore T-cell activation and antitumor immune responses. Preclinical studies reported high-affinity PD-1 binding, blockade of PD-1/ligand interactions and enhanced T-cell activity. (cancer.gov)

Efficacy

• Relapsed/refractory cHL: In a single-arm phase 2 trial involving 85 heavily pretreated patients, independently assessed objective response rate (ORR) was 90.6% (95% CI 82.3%–95.9%), including a 32.9% complete response rate. At 12 months, progression-free and overall survival rates were 78% and 99%, respectively. Median follow-up was 15.8 months. (pubmed.ncbi.nlm.nih.gov)
• Recurrent/metastatic cervical cancer: In a single-arm phase 2 study of 105 patients, zimberelimab monotherapy produced an independently assessed ORR of 27.6%, comprising 5.7% complete and 21.9% partial responses. Median overall survival was 16.8 months; median response duration had not been reached, with 74% of responses ongoing at 12 months. Responses were more frequent among tumors with higher PD-L1 expression. (pmc.ncbi.nlm.nih.gov)
• Zimberelimab has also shown activity in combination with chemotherapy, anti-TIGIT antibodies and other agents. These results cannot establish zimberelimab’s independent contribution and generally remain preliminary or investigational. (pmc.ncbi.nlm.nih.gov)

Safety

In the cHL study, 92.9% of patients experienced treatment-related adverse events and 28.2% had grade 3–4 events. The most frequent severe events included abnormal liver function (5.9%), hyperuricemia (4.7%), neutropenia (3.5%) and increased weight (3.5%). One fatal gastrointestinal infection occurred. (pubmed.ncbi.nlm.nih.gov)

In the cervical-cancer study, treatment-related adverse events occurred in 78.1% of patients and grade 3 or higher treatment-related events in 24.8%. Hypothyroidism and anemia were the most frequent treatment-related events; grade 3 or higher anemia occurred in 7.6%. Overall, the safety profile was consistent with PD-1 checkpoint inhibition, although evidence is based mainly on nonrandomized studies. (pmc.ncbi.nlm.nih.gov)

Further reading

• Phase 2 study in relapsed/refractory classical Hodgkin lymphoma
• Phase 2 study in recurrent or metastatic cervical cancer
• Preclinical characterization of zimberelimab
• Zimberelimab: First Approval
• NCI Drug Dictionary entry

Last updated: Sep 2026