Shanghai Henlius Biotech, Inc...announced that its first self-developed innovative PD-1 inhibitor HANSIZHUANG (generic name: serplulimab injection) has been approved by the National Medical Products Administration (NMPA) for the treatment of adult patients with advanced unresectable or metastatic MSI-H (Microsatellite Instability-High) solid tumors that have failed to respond to previous standard treatments, providing an alternative treatment option for patients.

...- Patients with unresectable or metastatic MSI-H or dMMR malignant solid tumors which are histopathologically or/and cytologically confirmed by the central laboratory or study sites;...

As of 9 January 2021, 108 patients were enrolled, and 68 patients with confirmed MSI-H solid tumours were included in the main efficacy analysis population (MEAP). The median follow-up duration in the MEAP was 7.7 months, with an ORR of 38.2% (95% confidence interval, 26.7–50.8). Of the 108 patients, grade ≥3 treatment-emergent adverse events were reported in 53 (49.1%) patients; immune-related adverse events occurred in 52 (48.1%) patients...Serplulimab demonstrates a durable antitumour effect and a manageable safety profile in previously treated patients with MSI-H solid tumours.

In this single-arm, open-label, multicenter, phase 2 study, patients aged 18–75 years with histologically or cytologically confirmed unresectable or metastatic MSI-H/dMMR solid tumors were enrolled to receive 3 mg/kg of intravenous serplulimab...Among them, 68 patients with confirmed MSI-H (by local sites or central lab) were included in the main efficacy analysis population (MEAP); 58 patients with confirmed MSI-H (by central lab) and had no major protocol deviations were included in the sensitivity analysis population (SAP). The median follow-up duration was 13.5 months in the MEAP and 14.0 months in the SAP. IRRC-assessed ORR per RECIST v1.1 was 39.7% (95% CI 28.0–52.3; 3 complete response [CR]) in the MEAP and 43.1% (95% CI 30.2–56.8; 2 CR) in the SAP. Investigator-assessed ORRs were 38.2% (95% CI 26.7–50.8; 1 CR) and 41.4% (95% CI 28.6–55.1; 1 CR) in the MEAP and the SAP, respectively. Median DoR, PFS, and OS were not reached; 12-month OS rate was 74.5% (95% CI 62.2–83.3) in the MEAP and 82.4% (95% CI 69.7–90.1) in the SAP.

In this single-arm, open-label, multicenter, phase 2 study (NCT03941574), patients (18≤ age ≤75 years) with histologically/cytologically confirmed unresectable or metastatic MSI-H/dMMR solid tumors were recruited to receive 3 mg/kg HLX10 every two weeks intravenously for up to 2 years until disease progression….HLX10 provides encouraging antitumor activity with a manageable safety profile in patients with MSI-H/dMMR solid tumors who have progressed on or been intolerant to standard therapies.