ESMO Congress 2026

Rolditamig deuderuxtecan (TQB2102) is a biapotropic ADC against HER2, simultaneously targeting the ECD2 and ECD4 extracellular domains, with a topoisomerase I payload and a DAR of ~6. As for the established evidence base of the HER2 ADC class, the background literature accompanying this report does not contain data from pivotal trials of same-class ADCs; the class-level evidence is therefore recorded here as not disclosed, no cross-trial numeric comparisons are made below, and all interpretation is based solely on the on-site posts.

What was actually reported at ESMO2026 is the APEX Breast01 study: in HER2-low metastatic breast cancer patients receiving first-line cytotoxic therapy with no prior chemotherapy, rolditamig deuderuxtecan was compared against TPC chemotherapy. Enrollment included 461 HR-positive and 81 TNBC patients, all PD-L1 negative. The core numbers: in all HER2-low patients, PFS improved from 5.5 months in the chemotherapy arm to 16.4 months, HR 0.29; OS showed an early trend, HR 0.44; ORR more than doubled (absolute values not disclosed). On safety, hematologic toxicity was most common; regarding ILD, two on-site posts gave different rates of 1.1% and 2.2% respectively (the latter noted no deaths), and the definition needs verification against the formal abstract.

In terms of the step forward, this readout uses a randomized controlled design to bring HER2-low ADC evidence into the first-line, chemotherapy-naive setting, covering a mixed HR+/TNBC cohort that was entirely PD-L1 negative; the numbers in the posts indicate a notable PFS effect size (HR 0.29) and an early OS trend (HR 0.44). The ECD2+ECD4 biparatopic design and DAR of ~6 are features distinguishing this molecule from conventional HER2 ADCs, but head-to-head or cross-trial data against same-class agents are not disclosed in this material, so relative positioning cannot be judged.

Regarding limitations: OS is only a trend, with maturity and follow-up time not disclosed; ORR is described only qualitatively without absolute values; subgroup results for HR+ versus TNBC are not disclosed; and the discrepancy between the two ILD rates suggests safety details await confirmation in formal publication. Moreover, no pivotal trials of same-class ADCs are provided in this material as reference, so all comparisons above are confined to the two arms within the trial.