DualityBio has initiated a trial of DB-1419, an anti-B7H3xPD-L1 BsAb ADC

Duality Biologics has initiated a trial (NCT06554795) of an anti-B7H3xPD-L1 BsAb ADC, DB-1419, in the United States, Australia, and China. However, Duality Bio has not yet submitted the IND application in China.

In 2023, BioNTech and DualityBio entered into a partnership to globally develop, manufacture, and commercialize two assets, including an ADC (DB-1311/BNT324) targeting B7H3.

Duality and BioNTech

DB-1419

DB-1419 is a bispecific antibody-drug conjugate targeting B7H3 and PD-L1. It was discovered by Duality Biologics and is still in the preclinical stage according to the pipeline on the official website. 

In 2022 and 2023, Duality Biologics filed patents (WO2024140846) covering anti-B7H3xPD-L1 BsAb ADCs. The patent includes examples of bispecific antibody-drug conjugates comprising the following components: an anti-B7H3 and PD-L1 bispecific antibody or an antigen-binding fragment thereof, a linker unit L, and TOP1 inhibitor, with a drug-to-antibody ratio (DAR) of 4, 6, or 8.

DSYE001-X1/2

DSYE001-X1 and DSYE001-X2 are two antibody-drug conjugates (ADCs) that are linked to the anti-B7H3xPD-L1 bispecific antibody DSYE001, designed to deliver the TOP1 inhibitors X1 and X2. DSYE-X1 demonstrated EC50 values of 6.2 nM, 226.8 nM, 14.3 nM, and 0.04 nM in the A375, NCI-H1975, NCI-H441, and NCI-H358 cell lines, respectively. The candidate DSYE-X1 (DAR6) was also tested in the NCI-H1975 (NSCLC) and MDA-MB-231 (breast cancer) xenograft mouse models as monotherapy or in combination with pembrolizumab (anti-PD-1 therapy).

in vivo data

Anti-B7-H3 Candidates in China

As of now, no anti-B7H3 therapies have received regulatory approval. Pharmaceutical technologies such as antibodies, ADCs, bispecific antibodies (BsAbs), and CAR-Ts targeting B7H3 are still under research in preclinical or clinical stages. So far, no other anti-B7H3xPD-L1 ADC or BsAb is in the clinical stage, either in China or globally.

Below is a list of anti-B7H3 candidates in China.

B7-H3 Landscape in China