Heyu-B (02256): Heyu Pharmaceutical announced preliminary phase II clinical results of oral PD-L1 inhibitor ABSK043 combined with EGFR inhibitor vumetinib in ESMO Asia 2025

Zhitong Finance App News, Heyu-B (02256) announced that on December 8, 2025, Shanghai Heyu Biomedical Technology Co., Ltd. (FAW Pharmaceutical) announced that it announced that it is developing ABSK043, an oral small molecule PD-L1 inhibitor ABSK043 and Shanghai Allis Pharmaceutical Technology Co., Ltd. (ALIS) third-generation EGFR-TKI vometinib for non-small cell lung cancer (NSCLC) at the 2025 European Society of Medical Oncology Asian Annual Meeting (ESMO Asia 2025) ABSK043 202) Positive results in the dose escalation phase. According to the data, the “target-free combination” scheme of ABSK043 and vormetinib showed good safety and tolerability. Based on the good safety of the protocol, the regulatory authorities agreed to expand it to first-line treatment studies for patients with EGFR mutations and PD-L1 positive NSCLC.

Epidermal growth factor receptor (EGFR) mutations are the most common carcinogenic driver gene mutations in NSCLC. Although third-generation EGFR-TKIs has become the first-line standard treatment for NSCLC with advanced EGFR mutations, studies have shown that patients with EGFR mutations combined with high PD-L1 expression benefit less from EGFR-TKIs treatment compared to patients with low or negative PD-L1 expression. Furthermore, although immunotherapy has shown excellent efficacy in many types of cancer, the combination regimen of PD-1/PD-L1 antibody and EGFR-TKI is limited due to serious toxic side effects, so the clinical needs of this type of patient population are still not being met.

At this year's ESMO Asia 2025, Professor Lu Shun of Shanghai Chest Hospital affiliated to Shanghai Jiao Tong University School of Medicine presented the positive results of the ongoing Phase II study (ABSK043-202) dose escalation phase in the form of a poster. In the dose escalation phase, a total of 21 patients with EGFR mutations and PD-L1 positive advanced NSCLC were included. Of these, 17 patients had received third-generation EGFR-TKIs.

Research results showed that ABSK043 combined with vometinib showed controlled safety and good tolerability. At the time of data analysis, no dose-limiting toxicity (DLTs) and interstitial pneumonia (ILD) had been observed. The most common treatment-related adverse effects (TEAES) were grade 1-2, and no grade 4 or 5 TEAE had been observed.

The combined regimen also showed positive anti-tumor activity. The disease control rate (DCR) assessed according to the RECIST v1.1 standard reached 71%, and a total of 14 patients achieved target lesion reduction. Of the 5 patients who achieved partial remission (PR), 4 were treated with third-generation EGFR-TKI. At the time of data analysis, the median duration of remission (DOR) had not been achieved.

The results of the dose-escalation phase showed that ABSK043 combined with vormetinib was not only safe and well-tolerated, but also showed encouraging initial anti-tumor activity. This innovative oral+oral “target-free combination” treatment strategy is expected to overcome the toxicity challenges faced by combining EGFR-TKIs with immunotherapy antibodies in the past. These positive results lay the foundation for the ongoing dose expansion phase, which will evaluate ABSK043 combined with vometinib as first-line therapy to treat patients with initially treated EGFR mutations and PD-L1-positive NSCLC.