2026 ESMO: Duality Bioics Reports Data from Three Trials of B7H3 ADC Elfe-D and HER3 ADC DB-1310

DualityBio's B7-H3 ADC elfetabart drozuntecan (DB-1311/BNT324, i.e., Elfe-D) is being developed in collaboration with BioNTech, and the two parties have repeatedly presented clinical data for this agent in advanced solid tumors at academic meetings. The global study of the HER3 ADC DB-1310 (NCT05785741) is a Phase 1/2, non-randomized design planning to enroll 1000 participants across 5 dose-level cohorts, with primary endpoints including dose-limiting toxicities, treatment-emergent adverse events, and serious adverse events; it started on 2023-08-17 with primary completion expected 2027-12-30, sponsored by DualityBio Inc.. On peer-reviewed platforms, DB-1310 showed a manageable safety profile and encouraging antitumor activity in heavily pretreated advanced solid tumors, particularly in EGFRm NSCLC（需要核查）.

The three studies presented at ESMO 2026 cover Elfe-D and DB-1310. Among them, the ADC+IO 2.0 global pan-tumor Phase 2 data are disclosed for the first time, and per the material this is the first clinical dataset read out for a PD-(L)1×VEGF bispecific combined with a B7-H3 ADC in solid tumors beyond lung cancer. Elfe-D combined with pumitamig showed encouraging early antitumor activity and deep responses in multiple late-stage solid tumors beyond lung cancer: in PROC (platinum-resistant ovarian cancer) patients, uORR reached 80.6% and DCR 90.3%; in HCC (hepatocellular carcinoma) patients, uORR was 42.9% and DCR 90.5%. The PROC data further showed that Elfe-D monotherapy demonstrated encouraging antitumor activity at two evaluated dose levels, with the combination achieving a uORR of 80.6%, providing a basis for subsequent dose optimization and combination strategy exploration.

Relative to prior materials, this release advances Elfe-D from monotherapy and lung cancer toward pan-tumor combination development: earlier company disclosures focused on B7-H3 ADC data presented alone or jointly with BioNTech, whereas this release adds global Phase 2 data for the combination with the PD-L1/VEGF-A immunomodulator pumitamig in solid tumors beyond lung cancer. The uORR of 80.6% and DCR of 90.3% in PROC, and uORR of 42.9% and DCR of 90.5% in HCC, provide preliminary efficacy support for the pan-tumor development of this novel-novel combination. For DB-1310, the registry shows the study still recruiting, with primary completion expected by end of 2027.

Undisclosed information includes: the specific enrollment numbers, dose-level details, duration of response, overall survival data, and detailed safety results for the Elfe-D combinations are not provided in the material (需要核查); the specific efficacy figures for DB-1310 in this release are also not listed in the material, 待确认. Upcoming milestones to watch include the full data release at the ESMO 2026 congress and the primary completion of the DB-1310 study by end of 2027.