Shanghai-based Abbisko Therapeutics (HKEX: 02256.HK) has entered a clinical collaboration with AstraZeneca (NYSE: AZN) to evaluate lumipodlin (ABSK043), a small-molecule PD-L1 inhibitor, in combination with osimertinib (Tagrisso) in EGFR-mutated, PD-L1 positive non-small cell lung cancer. The deal gives AstraZeneca a clinical partner for a novel immunotherapy modality with no approved precedent, while positioning Abbisko as the most clinically advanced oral PD-L1 program globally backed by a major pharma combination partner.
No financial terms were disclosed. The arrangement is a co-development collaboration rather than a licensing transaction: AstraZeneca contributes osimertinib as the combination backbone, Abbisko leads the Phase II study, and both parties share clinical trial responsibilities. Abbisko retains full ownership of lumipodlin. China's National Medical Products Administration cleared the IND for the combination on May 20, 2026.
Deal context
Lumipodlin is described by Abbisko as a selective small-molecule PD-L1 inhibitor that binds the PD-L1 receptor and induces its internalization from the cell surface, thereby blocking the PD-1/PD-L1 interaction and relieving T-cell suppression. In preclinical models, Abbisko reports anti-tumor activity comparable to approved PD-L1 antibodies, though no clinical efficacy data have been published. The molecule entered Phase I testing in advanced solid tumors in Australia and China, and has reached Phase II stage across various indications.
The biological rationale for the combination targets a specific unmet need: published clinical data indicate that EGFR-mutant patients with high PD-L1 expression derive less benefit from osimertinib monotherapy than those with low or negative PD-L1 expression. Prior attempts to combine osimertinib with anti-PD-1/PD-L1 antibodies, including pembrolizumab in the TATTON trial, were associated with excess pulmonary toxicity — a safety concern that an oral small molecule with a different pharmacokinetic profile may potentially circumvent, though this hypothesis has not been tested clinically.