Lepu Biopharma Co., Ltd. announced that it has obtained the latest data readout from the Phase Ia dose-escalation trial of CMG901 (a drug candidate co-developed by the company and Keymed Biosciences Inc. through a joint venture, KYM Biosciences Inc.) for advanced solid tumors. The Phase Ia Trial was designed to evaluate the safety, tolerability, pharmacokinetics, immunogenicity, and preliminary anti-tumor activity of CMG901 in patients with advanced solid tumors. During the dose-escalation phase, Claudin 18.2 expression was retrospectively tested by the central lab.

As of August 4, 2022, a total of 27 patients (13 gastric/gastroesophageal junction ("GC/GEJ") cancer and 14 pancreatic cancer patients) were enrolled in the Phase Ia Trial. The results showed that CMG901 was well-tolerated with a favorable safety profile. Drug-related grade 3 adverse events occurred in 3/27 (11.1%) patients.

No drug-related grade 4 adverse events were reported. Patients received CMG901 at dose levels up to 3.4 mg/kg, and maximum tolerated dose (MTD) was not reached. One patient in the 2.2 mg/kg cohort developed a dose-limiting toxicity.

Preliminary efficacy results demonstrated that in the 8 Claudin 18.2-positive GC/GEJ cancer patients receiving CMG901, objective response rate and disease control rate (DCR) were 75.0% (6/8) and 100% (8/8), respectively, with ORR of 100% in the 2.6, 3.0, and 3.4 mg/kg cohorts. Median progression free survival (mPFS) and median overall survival (mOS) were not reached yet. CMG901 showed a favorable safety and tolerability profile in this trial.

CMG901 at doses of 1.8 mg/kg yielded encouraging anti-tumor activity in patients with Claudin 18.2-positive GC/GEJ cancer. The Phase Ia Trial data has been presented as a poster at the 2023 Gastrointestinal Cancers Symposium of the American Society of Clinical Oncology (2023 ASCO GI).