ESMO Congress 2026

Izalontamab brengitecan (iza-bren, BL-B01D1) is a bispecific ADC targeting both EGFR and HER3. Before this lung cancer study, the asset had already secured randomized phase 3 evidence in nasopharyngeal carcinoma, at 2.5 mg/kg on days 1 and 8 every 3 weeks versus chemotherapy ^[2]; in EGFR-mutated NSCLC progressing after TKI therapy, a pooled analysis of phase I and phase II trials included 171 patients with a cORR of 47.4% (95% CI 39.7-55.1) and DCR of 81.3%, establishing the RP2D of 2.5 mg/kg on days 1 and 8 every 3 weeks ^[5]; in a phase Ib study of NSCLC with actionable genomic alterations outside classical EGFR mutations, the most common grade ≥3 TRAEs were thrombocytopenia (51.8%), anemia (44.6%), and neutropenia (43.4%) ^[4]. The molecule is currently listed among antibody therapeutics under regulatory review ^[1].

At ESMO26, Dr. Li Zhang (Sun Yat-sen University Cancer Center) presented PANKU-Lung01, a phase 3 trial: 432 patients with EGFR-mutant NSCLC progressing after third-generation EGFR TKI, versus platinum-based chemotherapy. mPFS by BICR was 11.1 vs 5.7 months, HR 0.40 (95% CI 0.31-0.51), p<0.0001; cORR was 60.2% vs 34.5%, and mDoR was 10.4 vs 5.7 months. OS is immature, with an 18-month OS rate of 68.8% vs 55.3% (another live post cited 1-year OS rates of 83% vs 73%). Safety was dominated by hematologic toxicities, with high dose reduction and interruption rates but low discontinuation rates. Also presented at the same meeting were positive phase 3 data for the HER3-targeting ADC ruzaltatug rezetecan, with live commentary noting DAR values of 8 and 4, respectively.

The main site news independently reported the same study, confirming the significant PFS benefit consistent with the live posts, and added the detail that the rate of grade ≥3 treatment-related adverse events was higher than with chemotherapy, with the population specified as advanced nonsquamous NSCLC; the authors stated that these results provide the first phase 3 evidence for bispecific antibody-drug conjugates [N1]. A separate Chinese industry news piece reported a more precise PFS of 11.14 months, described it as the longest second-line PFS, and disclosed that the molecule links a topoisomerase I inhibitor, Ed-04, via a tetrapeptide cleavable linker [N2].

Relative to prior knowledge, this study advances the single-arm signal from the pooled phase I/II analysis ^[5] into randomized controlled phase 3 evidence, with mPFS nearly doubled versus chemotherapy; the hematologic toxicity profile is consistent with the earlier phase Ib report ^[4][5]. Limitations include immature OS data, a grade ≥3 TRAE rate higher than chemotherapy [N1], high dose reduction and interruption rates suggesting that dose management will be a practical challenge, and the absence of a head-to-head comparison with ruzaltatug rezetecan presented at the same meeting.