The Zhitong Finance App learned that, according to Cornerstone Pharmaceutical's official website on October 24, Cornerstone Pharmaceutical (02616) announced registered clinical research data on frontline treatment of gastroesophageal adenocarcinoma with Zejemei (suglizumab injection) in the form of an oral report at the 2023 European Society of Internal Oncology (ESMO) annual meeting. The data published at this ESMO conference is based on the final analysis of PFS with a deadline of August 6, 2022, and the final analysis of the OS with a deadline of July 9, 2023. The results show that the GEMSTONE-303 study has reached the predetermined main end point of collaboration. Among patients with PD-L1 expression ≥ 5%, compared with placebo combined with chemotherapy, Zegemei combined with chemotherapy significantly improved PFS and OS, and the differences were statistically significant and clinically significant.

Key results are as follows:

The median PFS assessed by the researchers in the Zejemei treatment group and placebo group was 7.6 months vs. 6.1 months, risk ratio (HR) = 0.66 (95% CI, 0.54-0.81), P<0.0001.

OS between the Zejemei treatment group and the placebo group was 15.6 months vs. 12.6 months, risk ratio (HR) = 0.75 (95% CI, 0.61-0.92), P = 0.0060.

Subgroup analysis showed that all pre-defined subgroups, such as PD-L1 expression status, showed clinical benefits.

The ORR assessed by the researchers in the Zejemei treatment group and placebo group was 68.6% vs. 52.7%, and the median DoR was 6.9 months vs. 4.6 months.

Zejemei combined with chemotherapy is well tolerated and safe, and no new safety risks have been discovered.

Dr. Yang Jianxin, CEO of Cornerstone Pharmaceutical, said, “We are delighted to see that Zegemei's GEMSTONE-303 research data was accepted as a major summary (LBA) of this year's ESMO Annual Meeting and selected as an oral report. This fully confirms the international academic community's interest in progress in the field of gastric cancer and its recognition of the clinical value of Zejemei in first-line gastric cancer. Currently, no PD-L1 antibody has been approved for first-line treatment of gastroesophageal adenocarcinoma worldwide; at the same time, the marketing application for new indications for frontline treatment of advanced gastric cancer is being reviewed by the China State Drug Administration. We will continue to closely communicate with global regulators and look forward to bringing this innovative and effective treatment plan to more gastric cancer patients as soon as possible.”

Professor Shen Lin of Peking University Cancer Hospital, the main researcher of Ze Jiemei's GEMSTONE-303 study, said, “The number of new stomach cancer cases and deaths each year in China is close to half of the global total. In particular, patients with advanced or metastatic gastric cancer face a heavy burden of disease. Clinically, most patients with gastric adenocarcinoma have already entered an advanced stage at the time of initial diagnosis and cannot be surgically removed, and patients with advanced or metastatic gastric cancer usually have poor prognosis, and there are huge unmet medical needs. According to the GEMSTONE-303 study data released this time, Zegemei combined with chemotherapy can significantly prolong PFS and OS in patients with gastroesophageal junction adenocarcinoma, and is safe. We believe Zejemei can be a new treatment option for this patient group.”