CSPC's DP303c Research Findings Presented at ESMO

The 2023 European Society for Medical Oncology (ESMO) Congress has been convened in Madrid, Spain. The ESMO Congress, renowned as one of the most prestigious and academically influential international conferences, attracts experts and scholars in the field each year.

DP303c, the first ADC product independently developed by CSPC, has shown good anti-tumor activity. The results of DP303c's Phase I clinical study of in the treatment of advanced HER2-expressing solid tumors led by Professor Hu Xichun of Fudan University Shanghai Cancer Center were reported in Mini oral (No.385MO) at the 2023 ESMO Congress on October 22, 2023.

This was a multi-center Phase I clinical study (NCT04146610) to evaluate the safety, tolerability, initial efficacy, PK profile, and immunogenicity of DP303c in patients with advanced HER2-expressing solid tumors.

As of February 28, 2023, a total of 94 subjects were enrolled, including 68 with breast cancer, 10 with colon cancer, 9 with gastric cancer, and 7 with other tumor types, with a median follow-up of 11.98 months, and only one dose-limiting toxic event (grade 3 eye pain) during the dose escalation phase. The ORR and DCR were 42.9% (95%CI 32.5-53.7%) and 68.1% (95%CI 57.5-77.5%), respectively, in 91 patients assessable for efficacy. The ORR and DCR were 51.5% (95%CI 38.9-64.0%) and 77.3% (95%CI 65.3-86.7%), respectively, in 66 breast cancer subjects assessable for efficacy.

According to preliminary results, DP303c is of significant efficacy and good safety in patients with solid tumors, especially in those with breast cancer. Phase II pivotal studies of DP303c are ongoing.