Recently, the end-of-study analysis results from ASTRUM-005, a study of Henlius’ self-developed anti-PD-1 monoclonal antibody(mAb) HANSIZHUANG (serplulimab, trade name in Europe: Hetronifly®) in combination with chemotherapy for the first-line treatment of extensive-stage small cell lung cancer (ES-SCLC), were published in the internationally renowned oncology journal JAMA Oncology (impact factor: 23.9). The publication also reported patient-reported outcomes (PROs) data for the first time. The final analysis confirmed that serplulimab delivers durable and clinically meaningful survival benefits for patients with ES-SCLC, accompanied by a contemporaneous editor’s note that highly recognized the durable clinical benefit this study brings to patients with ES-SCLC. The relevant long-term follow-up data were first presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, and their publication in a top-tier journal now provides high-level evidence to inform global clinical practice, further reinforcing its leading position in the field of immunotherapy for small cell lung cancer.
In September 2022, the interim analysis of ASTRUM-005 was published in JAMA, becoming the first clinical immunotherapy study in small cell lung cancer worldwide to appear in the journal. In 2025, updated data analyses and biomarker exploration results were published in Cancer Communications. In addition, key data from ASTRUM-005 were presented at the ASCO Annual Meetings in 2022, 2024, and 2025, achieving coordinated dissemination through both major academic conferences and top-tier journals. This four-year academic journey, with three appearances in leading international journals, not only highlights the robustness of the study data but also reflects broad recognition from the global academic community.
4-Year OS Rate Reaches 21.9%, Further Validating Durable Long-Term Benefit Lung cancer remains the most commonly diagnosed cancer and the leading cause of cancer-related death worldwide, with approximately 2.5 million new cases and 1.8 million deaths reported globally in 2022.1 Small cell lung cancer (SCLC), the most aggressive subtype of lung cancer, accounts for around 15% of all lung cancer cases.2 Approximately two-thirds of patients with SCLC are diagnosed at the extensive stage, and the 5-year survival rate remains only 7%.2,3 ASTRUM-005 is a randomized, double-blind, international multicenter, placebo-controlled Phase 3 clinical trial designed to evaluate the efficacy and safety of serplulimab in combination with chemotherapy (carboplatin plus etoposide) as first-line treatment for ES-SCLC. Conducted across 114 investigational sites in 6 countries, the study enrolled 585 previously untreated patients with ES-SCLC. Based on the ASTRUM-005 results, serplulimab has been approved in 50 countries and regions, including China, the United Kingdom, the European Union, Singapore, India, Switzerland, and Peru, for the first-line treatment of ES-SCLC, making it the world’s first anti-PD-1 mAb approved for this indication. It has also received orphan drug designation from the U.S. FDA and other regulatory authorities, addressing a significant unmet clinical need. As of the data cutoff date of May 7, 2024, with a median follow-up of 42.4 months, the long-term follow-up results demonstrated durable survival benefits with the serplulimab-based regimen: Overall Survival (OS): Median OS reached 15.8 months in the serplulimab group, representing an extension of 4.7 months versus 11.1 months in the chemotherapy control group, with a 40% reduction in the risk of death (HR=0.60, 95% CI: 0.49–0.73, P<0.001). Long-term survival outcomes were particularly notable, with a 4-year OS rate of 21.9% in the serplulimab group—more than triple that of the chemotherapy group (7.2%). Tumor Response and Disease Control: Median progression-free survival (PFS) was 5.8 months in the serplulimab group versus 4.3 months in the chemotherapy group (HR=0.47, P<0.001). The objective response rate (ORR) improved to 68.9%, and median duration of response (DOR) was 6.8 months, both markedly superior to the control arm, suggesting that more patients achieved deeper and more durable tumor responses. Safety and Quality of Life: No new safety signals were identified during long-term follow-up. The incidence of grade ≥3 treatment-related adverse events was comparable between the serplulimab and chemotherapy groups (35.0% vs 29.1%). Meanwhile, PRO data showed that the serplulimab regimen prolonged survival without compromising patients’ quality of life.
As an innovative anti-PD-1 mAb independently developed by Henlius, serplulimab is distinguished by a differentiated mechanism. Preclinical studies have proven that serplulimab not only induces stronger PD-1 internalization—reducing PD-1 receptor presence on T cells for rapid and potent immune activation4—but also minimizes PD-1-mediated recruitment of the co-stimulatory molecule CD28, thereby preserving CD28 signaling,5-7 enhancing downstream AKT activity,8 and promoting sustained T-cell activation. Leveraging its unique mechanistic advantages, serplulimab has achieved breakthroughs in both lung cancer and gastric cancer. It is the world’s first anti-PD-1 mAb approved for first-line treatment of SCLC, and also the first and only* anti-PD-1 mAb approved for the perioperative treatment of gastric cancer. To date, serplulimab has been approved globally** for first-line treatment of squamous non-small cell lung cancer (sqNSCLC), ES-SCLC, esophageal squamous cell carcinoma (ESCC), and non-squamous non-small cell lung cancer (nsqNSCLC), as well as perioperative treatment of gastric cancer. Key clinical studies of serplulimab have been successively published in leading international medical journals, highlighting the strong value and leadership of its evidence base. In lung cancer, beyond the ASTRUM-005 study, results from the ASTRUM-004 study in first-line sqNSCLC and the ASTRUM-002 study in first-line nsqNSCLC were published in Cancer Cell and The Lancet Respiratory Medicine, respectively. In gastrointestinal cancers, the ASTRUM-006 study in perioperative gastric cancer and the ASTRUM-007 study in first-line ESCC were published in The Lancet and Nature Medicine, respectively, further reinforcing the academic influence of serplulimab across multiple tumor types. At the same time, Henlius continues to advance the global clinical development of serplulimab across high-incidence cancers, including lung cancer and gastrointestinal malignancies. In lung cancer, serplulimab now covers the full spectrum of first-line treatment for advanced lung cancer. Beyond already approved indications, patient enrollment has been completed in an international multicenter Phase 3 trial evaluating serplulimab in combination with chemotherapy and concurrent radiotherapy as first-line treatment for limited-stage SCLC (LS-SCLC). In addition, bridging studies for ES-SCLC being conducted in parallel in the United States and Japan have also completed enrollment. In gastrointestinal cancer, global enrollment has been completed in the international multicenter Phase 3 study ASTRUM-015, which is evaluating serplulimab in combination with bevacizumab and chemotherapy as first-line treatment for metastatic colorectal cancer (mCRC), with the potential to address an unmet need for immunotherapy in patients with MSS mCRC. In addition, serplulimab continues to make breakthroughs internationally, with its commercial footprint expanding rapidly. Up to date, it has been approved in 50 countries and regions including China, the United Kingdom, the European Union, Singapore, India, Switzerland, and Peru, covering nearly half of the global population. Henlius, together with its regional partners including Accord and Abbott, has continued to advance market access and commercialisation efforts for serplulimab in overseas markets. Since receiving its first approval in the European Union in February 2025, to date, serplulimab has been commercially launched in 16 European countries and has been included in reimbursement or public healthcare coverage systems in 10 countries, including Austria, Denmark, Germany, Ireland, Italy, Spain, and Sweden, thereby gaining access to mainstream healthcare systems in these markets. *As of June 22, 2026 **Approved indications may vary by country or region. Please refer to the prescribing information and approvals issued by the relevant local regulatory authorities. References 1. Bray F, Laversanne M, Sung H, et al. Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2024;74(3):229-263. doi:10.3322/caac.21834 2. Rudin CM, Brambilla E, Faivre-Finn C, Sage J. Small-cell lung cancer. Nat Rev Dis Primers. 2021;7 (1): 3. doi:10.1038/s41572-020-00235-0 3. American Cancer Society. Cancer facts & figures. Accessed December 26, 2025. http://www. cancer.org/content/dam/cancer-org/research/ cancer-facts-and-statistics/annual-cancer-factsand-figures/2021/cancer-facts-and-figures-2021. Pdf 4.Issafras H, et al. Structural basis of HLX10 PD-1 receptor recognition, a promising anti-PD-1 antibody clinical candidate for cancer immunotherapy. PLoS One. 2021;16(12):e0257972. 5.Hui E, et al. T cell costimulatory receptor CD28 is a primary target for PD-1-mediated inhibition. Science. 2017;355(6332):1428-1433. 6.Patsoukis N, et al. Interaction of SHP-2 SH2 domains with PD-1 ITSM induces PD-1 dimerization and SHP-2 activation. Commun Biol. 2020;3(1):128. 7.Fenwick C, et al. Tumor suppression of novel anti-PD-1 antibodies mediated through CD28 costimulatory pathway. J Exp Med. 2019;216(7):1525-1541. 8.Primavera E, et al. Computer-Aided Identification of Kinase-Targeted Small Molecules for Cancer: A Review on AKT Protein. Pharmaceuticals (Basel). 2023;16(7):993.
