Built on the foundation of Specificity Enhanced Bi-specific Antibody (SEBA) molecules, the SEBA-ADC have an advanced mechanism of action. This advanced functional class is referred to as Heterogeneity overcoming - Immunogenic death inducing - Resistance antagonizing - Enhanced Specificity (HIRE) molecules that target cancer cells. While HIRE molecules provide cancer cells specific targeting, and exert bi-modal proliferative inhibition, any cancer cell clones attempting proliferative escape are exposed to topoisomerase inhibition and die when attempting to duplicate.

The tetravalent HIRE BL-B01D1 has two binding domains for distinct Growth Factor Receptors that drive cancer cell proliferation and survival. Inheriting the SI-B001 mechanisms of action, BL-B01D1 blocks EGFR and HER3 signals to cancer cells, reducing proliferation and survival signals. Upon antibody mediated internalization, BL-B01D1 is trafficked to cancer cell lysosomes and liberates its therapeutic payload that induced genotoxic stress activating pathways leading to cancer cell death.

BL-B01D1 is currently being evaluated as a single agent in clinical trials enrolling patients with a variety of EGFR+ and HER3+ solid tumor types.