By Fineline Cube 
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. (HKG: 6990) announced that its Investigational New Drug (IND) application for SKB105, an integrin beta‑6 (ITGB6)‑targeted antibody‑drug conjugate (ADC), has been approved by the Center for Drug Evaluation (CDE) of China’s National Medical Products Administration (NMPA) for the treatment of advanced solid tumors.
Regulatory Milestone
| Item | Detail |
|---|---|
| Product | SKB105 (ITGB6‑targeted ADC) |
| Company | Sichuan Kelun‑Biotech (6990.HK) |
| Target | Integrin beta‑6 (ITGB6) |
| Payload | Topoisomerase 1 inhibitor |
| Regulatory Status | IND approved by CDE/NMPA |
| Indication | Advanced solid tumors |
| Technology | Kthiol irreversible conjugation |
Technology & Differentiation
Mechanism of Action: SKB105 targets ITGB6, which is overexpressed in many solid tumors but shows minimal to no expression in most normal tissues, potentially reducing systemic toxicity and off‑target effects.
Kthiol Conjugation: Proprietary irreversible conjugation technology enhances linker‑payload stability and tumor‑specific delivery, while reducing adverse effects compared to traditional ADCs.
Preclinical Profile: Demonstrated favorable efficacy, safety, and pharmacokinetic (PK) profile in preclinical models.
Strategic Crescent Biopharma Collaboration
In December 2025, Kelun‑Biotech entered into a strategic collaboration with Crescent Biopharma, Inc.:
| Product | Region | Rights Holder |
|---|---|---|
| SKB105 (CR‑003) | US, Europe, Ex‑Greater China | Crescent Biopharma |
| SKB118/CR‑001 (PD‑1×VEGF bispecific) | Greater China | Kelun‑Biotech |
Transaction Rationale: Cross‑license structure allows Kelun to monetize SKB105 globally while gaining access to SKB118/CR‑001, a PD‑1×VEGF bispecific antibody, for the Greater China market.
SKB118 IND: Kelun‑Biotech plans to submit an IND application for SKB118/CR‑001 in China in the near future.
Market Opportunity
Global ADC Market: $15 billion (2025), growing at 25% CAGR. ITGB6 is a novel target with limited competition, offering first‑mover advantage in solid tumors including lung, breast, pancreatic, and gastric cancers.
Revenue Projections:
- China Peak Sales: ¥3‑5 billion (US$420‑700M) by 2032
- Ex‑China Royalty: Mid‑teens royalties on Crescent’s global sales
Competitive Landscape
| ADC | Company | Target | Stage | Technology |
|---|---|---|---|---|
| SKB105 | Kelun‑Biotech | ITGB6 | Phase I ready | Kthiol conjugation |
| A166 | Kelun‑Biotech | HER2 | Phase II | Traditional conjugation |
| Enhertu | Daiichi/AZ | HER2 | Marketed | Traditional conjugation |
| Trodelvy | Gilead | TROP2 | Marketed | Traditional conjugation |
Differentiation: SKB105’s novel target and enhanced conjugation aim for improved safety and efficacy.
Forward‑Looking Statements
This brief contains forward‑looking statements regarding SKB105’s clinical development, commercial potential, and partnership outcomes. Actual results may differ materially due to clinical trial results, competitive dynamics, and regulatory decisions.-Fineline Info & Tech