Iza-bren was approved in China for recurrent or metastatic ESCC following progression on platinum-based chemotherapy and PD-1/PD-L1 inhibition.
China’s National Medical Products Administration (NMPA) has approved izalontamab brengitecan (iza-bren; formerly BL-B01D1) for the treatment of adult patients with recurrent or metastatic esophageal squamous cell carcinoma (ESCC) with disease progression following prior platinum-based chemotherapy and PD-1/PD-L1 inhibition.¹
The approval was supported by findings from the phase 3 PANKU-Esophagus01 trial (NCT06304974), which met its dual primary end points of overall survival (OS) and progression-free survival (PFS) benefits with iza-bren vs investigator’s choice of chemotherapy at a prespecified interim analysis. Findings from the trial showed that patients who received iza-bren achieved a median OS of 9.8 months vs 7.2 months for those given investigator’s choice chemotherapy (HR, 0.64; 95% CI, 0.49-0.83; P = .0004). The median PFS by blinded independent central review was 4.2 months vs 2.0 months, respectively (HR, 0.50; 95% CI, 0.40-0.63; P < .0001).
“The [PANKU-Esophagus01] study demonstrated significant improvements in both progression-free and overall survival compared with chemotherapy, supporting iza-bren as a new treatment option for these patients,” Jonathan Cheng, chief medical officer of SystImmune, stated in a news release.
Notably, iza-bren is under evaluation in multiple global studies in patients with non-small cell lung cancer, breast cancer, urothelial cancer, and other EGFR/HER3-expressing malignancies.
Iza-bren is a bispecific antibody-drug conjugate directed at both EGFR and HER3, receptors that are highly expressed across epithelial tumors and are associated with cancer cell proliferation and survival. Dual targeting blocks EGFR- and HER3-mediated signaling. Following antibody-mediated internalization, the agent’s topoisomerase I inhibitor payload is released, producing cytotoxic stress and cell death.
Iza-Bren in Pretreated Recurrent or Metastatic ESCC: PANKU-Esophagus01 Highlights
ESCC represents the second approved indication for iza-bren in China. In June 2026, the NMPA also approved the agent
PANKU-Esophagus01 was a randomized, open-label, multicenter trial that evaluated iza-bren compared with investigator’s choice chemotherapy in patients with recurrent or metastatic ESCC who had disease progression after platinum-based chemotherapy in combination with PD-1/PD-L1 inhibitor therapy.1,3 A total of 497 patients were randomly assigned across 80 centers in China. Iza-bren was administered at 2.5 mg/kg on days 1 and 8 every 3 weeks.3 Chemotherapy consisted of irinotecan, paclitaxel, or docetaxel.
PFS and OS served as the trial’s dual primary end points. Secondary end points included overall response rate (ORR), disease control rate (DCR), duration of response (DOR), safety, pharmacokinetics, and immunogenicity.
Further findings from PANKU-Esophagus01 presented at the
Treatment discontinuation due to treatment-related adverse effects occurred in 2.0% of patients treated with iza-bren, and the safety profile of the agent was consistent with that observed in prior studies of the agent.1,3 The rates of all-grade and grade 3 or higher interstitial lung disease were 1.6% and 0.8%, respectively, in the iza-bren arm vs 0.4% and 0%, respectively, in the chemotherapy arm.
