Phase 2 data at ESMO
Innovent Biologics presented Phase 2 data at the 2026 European Society for Medical Oncology Congress for IBI354, its HER2-targeted antibody–drug conjugate, in first-line treatment of breast cancer, the company said. The study tested IBI354 in combination with pertuzumab in patients with HER2-positive, unresectable locally advanced or metastatic breast cancer.
Response and follow-up
As of July 1, 20 patients were enrolled and received IBI354 at 9 mg/kg every three weeks alongside pertuzumab, the company said, with a median follow-up of 9.6 months and a median treatment duration of 42.21 weeks. The confirmed objective response rate was 95% and the disease control rate was 100%. Median follow-up for progression-free survival was 8.3 months; progression-free and overall survival were not yet mature, with one progression-free survival event and no overall survival events.
Safety findings
The most common treatment-emergent adverse events were nausea, vomiting and anemia, and no interstitial lung disease occurred. Four patients (20%) had treatment-related adverse events of Grade 3 or higher, two (10%) had dose interruptions because of them, one (5%) discontinued treatment and none had a dose reduction; no treatment-related adverse event led to death. Professor Xiaohua Zeng of Chongqing University Cancer Hospital said the profile showed no severe interstitial lung disease or the ocular toxicity commonly seen with other ADC drugs.
Phase 3 trials under way
Two pivotal Phase 3 studies, HeriCare-Breast01 and HeriCare-Ovarian01, have been initiated, and Innovent said further Phase 3 studies are being planned. Dr Hui Zhou, the company's chief R&D officer for its oncology pipeline, said the breast cancer data added to the clinical evidence supporting the drug's development.