CStone Secures US FDA IND Clearance for Trispecific Antibody CS2009 to Enter Phase II Trial

CStone Pharmaceuticals has announced that the US Food and Drug Administration (FDA) has cleared its Investigational New Drug (IND) application for CS2009, a novel trispecific antibody targeting PD-1, VEGF, and CTLA-4. The clearance enables the company to advance CS2009 into a Phase II clinical trial, marking a significant milestone in the development of next-generation immuno-oncology therapies designed to enhance anti-tumor efficacy through multi-target engagement.

Advancing Multi-Target Immuno-Oncology Innovation

CS2009 is engineered to simultaneously inhibit PD-1, VEGF, and CTLA-4 pathways, aiming to overcome resistance mechanisms and improve therapeutic outcomes compared to single- or dual-target therapies. By integrating immune checkpoint inhibition with anti-angiogenic activity, the candidate seeks to deliver a synergistic anti-cancer effect. The Phase II trial will further evaluate its safety, tolerability, and preliminary efficacy across selected tumor indications.

Strengthening CStone’s Global Oncology Pipeline

The FDA clearance reinforces CStone’s strategic focus on innovative biologics and its commitment to expanding its global clinical footprint. Progressing CS2009 into Phase II positions the company competitively within the evolving immunotherapy landscape, where multi-specific antibodies are gaining attention as potential solutions to improve response rates and durability in oncology treatment.