Alphamab Oncology...announced that, the recombinant humanized PD-L1 single-domain antibody Envafolimab (Project Code: KN035) was granted priority review by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA). The Envafolimab BLA is accepted for the treatment of microsatellite instability-high (MSI-H) advanced colorectal cancer, gastric cancer / mismatch repair deficient (dMMR) advanced solid tumors that have failed previous standard of care.

One hundred and three patients (65 with colorectal cancer, 18 with gastric cancer, and 20 with other solid tumors) were enrolled....Median progression-free survival was 11.1 months (95% CI 5.5 to not evaluable). Overall survival at 12 months was 74.6% (95% CI 64.7–82.1)....Envafolimab was effective and had acceptable safety in the treatment of previously treated advanced dMMR/MSI-H solid tumors.

...103 pts with dMMR/MSI-H advanced cancer were enrolled, including 65 with colorectal cancer...18 with gastric cancer (GC)…The 12 months OS rate was 72.9%, 83.3%, 75.0% and 74.6% for CRC, GC, other tumors, and overall population, respectively….Envafolimab demonstrated robust anti-tumor activity with a manageable safety profile in heavily pretreated pts with dMMR/MSI-H cancer.

The PEPi included 39 patients with CRC and 11 with GC, with a median follow-up of 7.5 months. Median progression-free survival was 6.6 months in both the PEPi and the overall population. Envafolimab demonstrated durable anti-tumor activity with a manageable safety profile in patients with previously treated advanced MSI-H/dMMR cancer.