Pucotenlimab (HX008): A Comprehensive Clinical and Scientific Monograph

Executive Summary

Pucotenlimab is a next-generation, recombinant humanized anti-programmed cell death protein 1 (PD-1) monoclonal antibody representing a significant advancement in the field of immuno-oncology. Developed with a "best-in-class" strategic approach, its primary molecular innovation is an engineered Fragment crystallizable (Fc) domain that confers a uniquely prolonged pharmacokinetic half-life, a key differentiator in the competitive landscape of immune checkpoint inhibitors. This report provides a comprehensive analysis of Pucotenlimab's molecular profile, mechanism of action, clinical development program, and regulatory standing, synthesizing data from preclinical studies to late-stage clinical trials.

The drug has secured conditional marketing approvals from China's National Medical Products Administration (NMPA) for two key indications: the treatment of unresectable or metastatic microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) solid tumors, and for unresectable or metastatic melanoma in patients who have failed prior systemic therapy. These approvals are underpinned by robust clinical evidence, most notably from the pivotal Phase 2 study (NCT03704246) in MSI-H/dMMR tumors. Long-term follow-up from this trial demonstrated not only a high objective response rate of 50.0% but also exceptional durability, with a median progression-free survival of 33.8 months and a median overall survival of 55.9 months in a heavily pre-treated patient population.