The 2025 European Society For Medical Oncology Immuno-Oncology Congress (ESMO IO 2025) was held in London, UK, from December 10–12, 2025. At the congress, real-world data from a multicenter, prospective study of its self-developed innovative monoclonal antibody(mAb), HANSIZHUANG (serplulimab, Hetronifly^® in Europe)  as a first-line treatment for patients with small cell lung cancer (SCLC) and brain metastases were released. The preliminary results suggest that serplulimab-based therapy may offer potential therapeutic benefits for previously untreated SCLC patients with brain metastases.

Lung cancer is one of the most common malignancies around the world. SCLC is the most aggressive subtype of lung cancer, accounting for around 15% of all lung cancer cases^[1]. The SCLC breaks down into limited stage small cell lung cancer (LS-SCLC) and extensive-stage small cell lung cancer (ES-SCLC). Serplulimab is the world’s first anti-PD-1 mAb approved for the first-line treatment of small cell lung cancer (SCLC), and the first  anti‑PD‑1 mAb to have succeeded in a phase 3 registration study for perioperative gastric cancer. Up to date, serplulimab has been approved for the treatment of squamous non-small cell lung cancer (sqNSCLC), extensive-stage small cell lung cancer (ES-SCLC), esophageal squamous cell carcinoma (ESCC), and non-squamous non-small cell lung cancer (nsqNSCLC). It has been approved in 40 countries and regions including China, the U.K., Germany, Singapore, Switzerland and India, covering nearly half of the global population and accelerating global accessibility. Serplulimab demonstrates unique advantages in treating various solid tumors via its differentiated mechanism, especially achieving groundbreaking progress in both lung and gastric cancers. The results of 4 pivotal trials of serplulimab were published in the Journal of the American Medical Association (JAMA), Nature Medicine, Cancer Cell and British Journal of Cancer, respectively. It has also received orphan drug designations granted by the US FDA, the European Commission, Swissmedic, Korea MFDS and Mexico COFEPRIS.

In lung cancer, serplulimab has covered the full range of first-line treatment. Beyond its three approved indications (sqNSCLC, ES-SCLC, nsqNSCLC), Henlius is conducting a global, multicenter Phase 3 trial of serplulimab plus chemotherapy and radiotherapy for first-line treatment of limited-stage SCLC (LS-SCLC).  Additionally, bridging studies for ES-SCLC are underway in both the U.S. and Japan. The phase 3 clinical trial for LS-SCLC and the head-to-head bridging study for ES-SCLC in the U.S. have both completed patient enrollment.

The real-world study data findings released at the ESMO IO 2025 conference are as follows^[2]:

Title：Serplulimab Combined with Chemotherapy as First-line Therapy in Small-cell Lung Cancer Patients with Brain Metastases: A Multicenter, Prospective Real-World Study

Study design: This prospective real-world study was conducted across eleven centers in China and included adult patients with previously untreated SCLC and BM. Patients received serplulimab plus platinum-based chemotherapy, followed by serplulimab maintenance therapy until disease progression or intolerable toxicity. The primary endpoint was intracranial progression-free survival (iPFS); secondary endpoints included PFS, overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety.

Results: The median iPFS was 8.9 months (95% CI: 6.5 - 18.3), and the median PFS was 8.7 months (95% CI: 6.5 - 17.9). Median iPFS was numerically longer in patients who initially received intracranial radiotherapy than in those who never received it (18.1 vs. 8.9 months, P = 0.234). The intracranial ORR and intracranial DCR were 76.2% (95% CI: 60.6 - 88.0%) and 90.5% (95% CI: 77.4 - 97.3%), respectively. The overall ORR and DCR were 83.3% (95% CI: 68.6 - 93.0%) and 90.5% (95% CI: 77.4 - 97.3%), respectively. The OS data were immature, with a 1-year OS rate of 83.0% (95% CI: 71.3 - 96.5%). The incidence of overall adverse events (AEs) was 61.9% (n = 26), with 23.8% (n = 10) of patients reporting grade ≥ 3 AEs. Eight patients (19.1%) had grade ≥ 3 immune-related AEs.

Conclusion: Preliminary findings suggest that serplulimab-based therapy shows potential therapeutic benefits for previously untreated SCLC with BM. Patient follow-up is continuing, and further evaluation is warranted.

【Reference】

[1] Eskandar A, Ahmed A, Daughtey M, et al. Racial and sex differences in presentation and outcomes of small cell lung cancer in the United States: 1973 to 2010[J].Chest, 2015,147(4): e164-e165.

[2] Guanming Jiang et al. 2025 ESMO IO. 155P.