By Fineline Cube 
Abbisko Cayman Limited (HKG: 2256) announced preliminary results from the dose escalation phase of the ongoing Phase 2 study (ABSK043-202) for its oral small‑molecule PD‑L1 inhibitor ABSK043 combined with third‑generation EGFR‑TKI firmonertinib in non‑small cell lung cancer (NSCLC) at the European Society for Medical Oncology Asia Congress 2025 (ESMO Asia 2025).
Clinical Data Summary
Safety Profile (Favorable)
| Safety Metric | Result | Significance |
|---|---|---|
| DLTs | None observed | Well‑tolerated across dose levels |
| ILD | None observed | Critical for EGFR‑TKI combinations |
| TEAEs | All Grade 1‑2 | Manageable safety profile |
| Severe AEs | No Grade 4 or 5 | Supports further development |
Efficacy Results (Promising)
| Endpoint | Result | Clinical Context |
|---|---|---|
| Disease Control Rate (DCR) | 71% (14/14 patients) | Strong tumor control signal |
| Partial Response (PR) | 5 patients | 4 had prior 3rd‑gen EGFR‑TKI exposure |
| Target Lesion Regression | 14 patients | Majority showed tumor shrinkage |
| Median DOR | Not reached | Durability data immature |
Drug Profile & Combination Rationale
ABSK043: Oral small‑molecule PD‑L1 inhibitor targeting immune evasion
Firmonertinib: Third‑generation EGFR‑TKI for EGFR‑mutated NSCLC
“Targeted‑plus‑immuno‑therapy”: Combines precision oncology with immunotherapy to overcome resistance
Strategic Rationale:
- Addresses unmet need in EGFR‑TKI pretreated patients
- Avoids ILD risk seen with other EGFR/IO combinations
- Oral convenience vs. injectable PD‑1/PD‑L1 inhibitors
Market Context & Strategic Outlook
- NSCLC Market: China has ~800,000 new lung cancer cases annually; EGFR‑mutated subset represents 40‑50%
- Competitive Landscape: Dominated by osimertinib (Tagrisso) and PD‑1 inhibitors; limited options post‑TKI failure
- Commercial Potential: Analysts project ¥2‑3 billion peak sales if approved in 3rd‑line+ setting
- Next Milestones: Phase 2 expansion cohort ongoing; registration strategy to be finalized based on durability data
- Global Ambition: ESMO Asia presentation signals intent for international development pathway
Forward‑Looking Statements
This brief contains forward‑looking statements regarding ABSK043 development timelines, clinical outcomes, and market potential. Actual results may differ due to clinical, regulatory, and competitive uncertainties.-Fineline Info & Tech