By Fineline Cube Sichuan Biokin Pharmaceutical Co., Ltd. (SHA: 688506) announced that iza-bren (izalontamab brengitecan, BL-B01D1), its first‑in‑class EGFR×HER3 bispecific antibody‑drug conjugate (ADC), has been included in the Priority Review list by China’s Center for Drug Evaluation (CDE) for the treatment of recurrent or metastatic esophageal squamous cell carcinoma (ESCC) in patients who have failed prior PD‑1/PD‑L1 monoclonal antibodies combined with platinum‑containing chemotherapy. This marks the second Priority Review designation for BL-B01D1, following a similar nod for nasopharyngeal carcinoma in September 2025.
Regulatory & Product Milestone
| Item | Detail |
|---|---|
| Product | iza-bren (izalontamab brengitecan, code: BL-B01D1) |
| Company | Sichuan Biokin Pharmaceutical (688506.SH) |
| Regulatory Status | CDE Priority Review for ESCC indication |
| Indication | Recurrent/metastatic ESCC (post‑PD‑1/PD‑L1 + platinum) |
| Mechanism | EGFR×HER3 bispecific ADC (first‑in‑class) |
| Development Stage | Phase 3 (over 40 active trials globally) |
| Previous Priority Review | Nasopharyngeal carcinoma (Sep 2025) |
Technology Differentiation
First‑in‑Class Bispecific ADC: BL-B01D1 is the only EGFR×HER3 bispecific ADC in clinical development, offering dual targeting of two key receptors overexpressed in solid tumors.
Advantages Over Monospecific ADCs:
- Broader Coverage: Co‑targeting compensates for tumor heterogeneity and resistance
- Internalization Synergy: Enhanced tumor cell uptake via avidity effects
- Resistance Overcome: Active against EGFR‑resistant and HER3‑upregulated tumors
Clinical Evidence: Phase 1/2 data showed objective response rate (ORR) of 42% in heavily pretreated ESCC patients, with median duration of response (DOR) of 8.5 months and manageable safety profile (Grade ≥3 adverse events in 18% of patients).
Market Opportunity: ESCC in China
Disease Burden:
- Incidence: 300,000‑350,000 new ESCC cases annually in China (50% of global total)
- Recurrent/Metastatic: 60‑70% of patients develop advanced disease
- PD‑1/PD‑L1 Failure: 40‑50% of patients progress after first‑line immunotherapy + chemotherapy
Treatment Gap:
- Current Standard: Chemotherapy alone (docetaxel, paclitaxel) yields ORR <15% and median PFS 3‑4 months
- ADC Landscape: No approved ADCs for ESCC; Enhertu (HER2) limited to <10% HER2‑positive patients
Market Size:
- China ESCC Market: ¥18 billion (2025), projected ¥25 billion by 2030
- Target Population: ~80,000‑100,000 eligible patients for BL-B01D1 annually
- Peak Sales Potential: ¥3.5‑4.5 billion (US$490‑630 million) by 2029, capturing 35‑40% market share
Competitive Landscape
| Drug | Company | Target | Stage (China) | Annual Cost (¥) |
|---|---|---|---|---|
| BL-B01D1 | Sichuan Biokin | EGFR×HER3 ADC | Priority Review | ¥180,000‑220,000 (projected) |
| Enhertu | Daiichi/AZ | HER2 ADC | Approved | ¥250,000‑300,000 |
| Tiselizumab | BeiGene | PD-1 | Marketed | ¥100,000‑120,000 |
| Docetaxel | Generic | Chemotherapy | Marketed | ¥8,000‑12,000 |
| Camrelizumab | Hengrui | PD-1 | Marketed | ¥90,000‑110,000 |
Strategic Differentiation: BL-B01D1’s bispecific targeting and first‑in‑class status justify premium pricing vs. chemotherapy and positions it as best‑in‑class ADC for ESCC.
Clinical Development & Expansion
Phase 3 Status:
- ESCC Study: Global trial (NCT05987663) enrolling 400 patients comparing BL-B01D1 vs. chemotherapy in second‑line ESCC
- Nasopharyngeal Carcinoma: Priority Review granted Sep 2025; NDA submission expected Q2 2026
- Pipeline: 40+ active trials across lung, breast, gastric, and colorectal cancers in China and U.S.
Manufacturing:
- Biokin’s Chengdu facility (capacity: 500 kg/year ADC production) already GMP‑certified and supplying Phase 3 trials
- Plans to triple capacity by 2027 to meet commercial demand
Financial Implications
Valuation Impact: Priority Review designation derisks regulatory pathway and could add ¥5‑8 billion to Biokin’s market capitalization upon NDA approval.
Revenue Model:
- 2026E: ¥250 million (nasopharyngeal carcinoma launch)
- 2027E: ¥1.2 billion (ESCC approval)
- 2028E: ¥2.8 billion (expanded indications)
- Peak: ¥4.5 billion (ESCC + nasopharyngeal + other solid tumors)
Licensing Potential: Biokin is in discussions with global pharma for ex‑China rights, with potential USD 500‑800 million upfront valuation.
Forward‑Looking Statements
This brief contains forward‑looking statements regarding BL‑B01D1’s regulatory approval timeline, market penetration, revenue forecasts, and competitive positioning. Actual results may differ materially due to NMPA review outcomes, clinical trial results, competitive responses, and market access policies.-Fineline Info & Tech