Sugemalimab Earns Chinese Approval for Esophageal Squamous Cell Carcinoma

"The GEMSTONE-304 study [NCT04187352] demonstrated that sugemalimab in combination with chemotherapy significantly improved PFS and OS compared [with] first-line chemotherapy for ESCC, with a manageable safety profile," according to principal investigator Li Jin, MD, PhD.

A supplemental biologics license application (sBLA) for frontline sugemalimab (Cejemly) plus fluorouracil and platinum-based chemotherapy has received approval from China’s National Medical Products Administration for patients with unresectable locally advanced, recurrent, or metastatic esophageal squamous cell carcinoma (ESCC), according to a press release from CStone Pharmaceuticals.¹

Sugemalimab’s approval was based on data from the phase 3 GEMSTONE-304 study (NCT04187352), the results of which were presented at the 2023 European Society for Medical Oncology (ESMO) World Congress on Gastrointestinal Cancer and published in Annals of Oncology.² Investigators reported a prolonged progression-free survival (PFS) benefit by blinded independent central review among patients treated with sugemalimab and chemotherapy compared with placebo and chemotherapy at a median follow-up of 15.2 months. The median PFS in each respective group was 6.2 months vs 5.4 months (HR, 0.67; 95% CI, 0.54-0.82; P = .0002).

Additionally, the median overall survival (OS) was 15.3 months in the sugemalimab arm compared with 11.5 months in the placebo arm (HR, 0.70; 95% CI, 0.55-0.90; P = .0076). Improvements in both PFS and OS were observed across most prespecified subgroups, which included various PD-L1 expressions.

Moreover, the sugemalimab regimen resulted in an overall response rate of 60.1% compared with 45.2% in the placebo arm. The median duration of response was 6.0 months compared with 4.5 months, respectively.

“Esophageal cancer is a prevalent malignancy in China, with ESCC being the most common in terms of pathological type,” principal investigator Li Jin, MD, PhD, director of the Department of Oncology, East Hospital, Tongji University, said in the press release.¹

“About 70% of patients with esophageal cancer have progressed to locally advanced or advanced stages at the time of initial diagnosis. In addition, 50% to 60% of patients with resectable esophageal cancer relapse or develop distant metastases after radical surgery. The GEMSTONE-304 study demonstrated that sugemalimab in combination with chemotherapy significantly improved PFS and OS compared [with] first-line chemotherapy for ESCC, with a manageable safety profile. We believe, with this approval, sugemalimab will provide a new first-line treatment option to patients with advanced ESCC.”

Investigators reported grade 3 or higher treatment-related adverse effects (TRAEs) in 51.3% of patients in the sugemalimab cohort vs 48.4% in the placebo cohort, as well as serious TRAEs in 21.5% vs 13.2%, respectively.² Additionally, treatment discontinuations due to treatment-emergent AEs and TRAEs leading to death were reported in 13.3% vs 10.4% and 1.7% vs 0.5%, respectively.

“We are excited about the approval of sugemalimab for the fourth indication in first-line ESCC, which further demonstrates its clinical significance and potential,” Jason Yang, MD, PhD, chief executive officer at CStone, explained.¹ “In additional to the approved indications such as non–small cell lung cancer [NSCLC], NK/T-cell lymphoma, and ESCC, sugemalimab is currently under review for its sBLA for the first-line treatment of gastric cancer. We are keeping active and productive communication with the NMPA to secure early approval in China and will also work with the FDA and European Medicines Agency [EMA] to explore registration pathways in the U.S, Europe, and other territories. We look forward to benefiting more patients with ESCC around the world with sugemalimab.”

References

1. CStone announces NMPA approval of sugemalimab as first-line treatment for esophageal squamous cell carcinoma. News release. CStone. December 8, 2023. Accessed January 3, 2024. https://bit.ly/4aFuUX4
2. Li J, Chen Z, Bai Y, et al. O-4 GEMSTONE-304: a phase 3 study of sugemalimab plus chemotherapy versus chemotherapy as first-line treatment of patients with unresectable locally advanced, recurrent or metastatic esophageal squamous cell carcinoma (ESCC). Ann Oncol. 2023;34(suppl 1):S181-S182. doi:10.1016/j.annonc.2023.04.019