Innovent Biologics, Inc., a world-class biopharmaceutical company that develops, manufactures and commercializes high quality medicines for the treatment of oncology, cardiovascular and metabolic, autoimmune, ophthalmology and other major diseases, announces that the New Drug Application (NDA) for ipilimumab injection (anti-CTLA-4 monoclonal antibody; R&D Code: IBI310) has been accepted by the Center for Drug Evaluation (CDE) of China's National Medical Products Administration (NMPA) and granted Priority Review designation[1] in combination with sintilimab as neoadjuvant treatment for resectable microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR) colon cancer.

This is China's first NDA for a domestic CTLA-4 inhibitor and another milestone strengthening sintilimab's leadership position in cancer immunotherapy. Immune checkpoint blockade (ICB) therapy targeting PD-1 and CTLA-4 has transformed oncology treatment, ipilimumab with sintilimab as a neoadjuvant treatment could increase R0 resection rate, achieve pathological complete response, and relieve the majority of patients from adjuvant chemotherapy burdens. This novel treatment is also expected to reduce recurrence rate and improve long-term prognosis, anticipated to benefit MSI-H/dMMR colon cancer patients upon NDA approval.

The NDA acceptance and Priority Review designation are based on results from a randomized, controlled, multicenter, pivotal Phase 3 clinical trial (NeoShot, NCT05890742) which evaluated the safety and efficacy of ipilimumab  combined with sintilimab as neoadjuvant therapy and as compared with direct radical surgery for MSI-H/dMMR colon cancer. The primary endpoints are pathologic complete response (pCR) rate and event-free survival (EFS). Interim analysis by the Independent Data Monitoring Committee (IDMC) showed that the NeoShot trial has met its primary endpoint. Detailed results will be presented at future academic conferences or published in academic journals.

Previously, the results of a randomized controlled Phase 1b trial evaluating ipilimumab in combination with sintilimab as neoadjuvant treatment for MSI-H/dMMR colon cancer were presented orally at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting. Based on promising Phase 1b results, the CDE has granted Breakthrough Therapy Designation (BTD) for ipilimumab.