Henlius reports positive results from ASTRIDE U.S. bridging study for serplulimab in combination with chemotherapy for first-line treatment of patients with extensive-stage small cell lung cancer (ES-SCLC)

• ASTRIDE trial for first-line ES-SCLC demonstrated favorable median overall survival in serplulimab with chemotherapy versus atezolizumab plus chemotherapy
• Study enrolled over 200 U.S. patients, including underrepresented racial and ethnic populations
• Results support ASTRUM-005, a global, randomized, double-blind Phase 3 trial, which showed statistically significant overall survival benefit

SHANGHAI, Oct. 27, 2026 /PRNewswire/ -- On October 26, 2026, Shanghai Henlius Biotech, Inc ("Henlius"), a global, innovation-driven biopharmaceutical company, announced at the European Society for Medical Oncology (ESMO) Congress 2026, positive results from ASTRIDE, a randomized, descriptive, open-label, U.S. study of serplulimab (in Europe, Hetronifly^®), an anti-PD-1 monoclonal antibody (mAb), in combination with carboplatin and etoposide (chemotherapy) compared to atezolizumab plus chemotherapy for first-line treatment of patients with extensive-stage small cell lung cancer (ES-SCLC). The study is led by David R. Gandara, MD, Professor Emeritus at the University of California Davis Comprehensive Cancer Center in Sacramento, California.

As of data cutoff on February 18, 2026, the median follow-up duration was 14.1 months. Despite a higher proportion of patients with liver metastasis in the serplulimab group than in the atezolizumab group (49.5% vs 40.0%), median OS was numerically longer with serplulimab than with atezolizumab (12.4 vs 10.2 months; hazard ratio [HR], 0.82; 95% confidence interval [CI], 0.56-1.20). One-year OS rates were 52.4% and 41.4%, and two-year OS rates were 32.2% and 17.6%, respectively.

David R. Gandara, MD, Professor Emeritus at the University of California Davis Comprehensive Cancer Center and the leading principal investigator in the ASTRIDE trial said, "ES-SCLC is a rapidly progressive and life-threatening disease. Overall survival is the primary endpoint. The results are remarkably consistent with those of ASTRUM-005. In particular, the two-year survival rate of 32% is identical in both studies, ASTRIDE and the previous ASTRUM-005 phase 3 trial. These results provide an important clinical assessment of serplulimab in the U.S. patient population and strongly support the benefit of serplulimab and applicability of the ASTRUM-005 findings to the U.S. patients with ES-SCLC in the first-line setting."

Dr. Jason Zhu, Executive Director and Chief Executive Officer of Henlius, said, "Serplulimab is a current treatment option for patients in Europe and other global markets, and the results from our ASTRIDE study, combined with our ASTRUM-005 Phase 3 trial, reflect the potential benefit for U.S. patients with ES-SCLC, a rare and aggressive disease. These encouraging results further validate our strategy and commitment to finding better treatment options for patients worldwide."

Summary of ASTRIDE Results

ASTRIDE is a randomized, open-label, descriptive, U.S. trial conducted in the United States. Between 2022 and 2025, it randomized 201 patients across 63 sites with ES-SCLC 1:1 to serplulimab 300 mg every three weeks plus carboplatin and etoposide or atezolizumab 1,200 mg every three weeks plus carboplatin and etoposide. Atezolizumab was selected as the active comparator because it is most widely used in U.S. practice. The ASTRIDE protocol was amended in June 2024 to allow newly diagnosed patients to receive one cycle of chemotherapy before randomization. The amendment allowed participation of eligible U.S. patients who needed to begin chemotherapy treatment before completing trial screening for enrolment and helped increase accrual.

The primary endpoint is OS, and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), duration of response (DOR), assessed by blinded independent central review (BICR), together with safety. Analyses were descriptive, and no formal hypothesis testing for superiority or noninferiority was planned.

Median PFS assessed by blinded independent central review (BICR) was 5.4 months with serplulimab and 4.9 months with atezolizumab. ORR was 65.7% and 67.0%, and median DOR was 4.2 and 4.0 months, respectively. In total, 158 patients in the ITT population had no prior chemotherapy for newly diagnosed ES-SCLC (serplulimab group: 82 patients; atezolizumab group: 76 patients). Among these patients, the median OS was 13.4 and 10.8 months in the respective groups, with an HR of 0.77 (95% CI, 0.50–1.17).

Safety profiles were similar between the groups. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 73.7% of patients in the serplulimab group and 73.0% of patients in the atezolizumab group. Grade ≥3 TEAEs related to serplulimab or atezolizumab occurred in 20.2% and 25.0% of patients, respectively. Immune-related adverse events occurred in 21.2% and 23.0% of patients, respectively.

The ASTRIDE study is conducted exclusively in the U.S. and includes underrepresented groups, including 5% of patients who are Black or African American and 4.5% of patients are Hispanic or Latino. ASTRIDE is a complementary study to the global phase 3 ASTRUM-005 study.

ASTRUM-005

ASTRUM-005, was a randomized, double-blind, international, phase 3 clinical study aimed to compare the efficacy and safety of serplulimab with placebo when combined with chemotherapy (carboplatin-etoposide) in previously untreated patients with ES-SCLC. Enrolled patients were randomized 2:1 to receive intravenous infusion of either serplulimab or placebo in combination with chemotherapy every three weeks until disease progression, death, intolerable toxicity, withdrawal of informed consent, or other reasons specified in the protocol (whichever occurred first). The primary endpoint of this study was overall survival (OS). The secondary endpoints included progression-free survival (PFS), objective response rate (ORR), duration of response (DOR), safety, pharmacokinetic characteristics, and immunogenicity. ASTRUM-005 included a total of 128 sites in countries including Türkiye, Poland, Georgia, and China, and enrolled 585 subjects from 114 sites, among whom 31.5% were White. In December 2021, ASTRUM-005 met its primary study endpoint of the overall survival (OS) in the interim analysis and demonstrated a manageable safety profile.

Serplulimab

Serplulimab, an anti-PD-1 mAb, has been approved in more than 50 countries and regions for first-line treatment of ES-SCLC, squamous non-small cell lung cancer (sqNSCLC), esophageal squamous cell carcinoma (ESCC), non-squamous non-small cell lung cancer (nsqNSCLC), and is the world's first and only^[i] anti-PD-1 monoclonal antibody approved for perioperative treatment of gastric cancer.^[ii] It is included in reimbursement or public healthcare coverage systems of more than 10 countries, including the U.K., Germany, Italy, and Spain. FDA granted serplulimab orphan-drug designation for the treatment of small cell lung cancer in March 2022.

About Henlius

Shanghai Henlius Biotech, Inc. is a global, innovation-driven biopharmaceutical company committed to delivering high-quality biologic therapies to patients worldwide. Founded in 2010, Henlius focuses on oncology, autoimmune diseases, and ophthalmic diseases, with end-to-end capabilities spanning research and development, clinical operations, regulatory affairs, manufacturing, and commercialization. Its portfolio of innovative medicines and biosimilars includes 10 products approved across more than 60 countries and regions. Guided by a patient-centered mission, Henlius works to address unmet medical needs and turn scientific advances into meaningful value for patients and healthcare systems. For more information, visit https://www.henlius.com/en/index.html. 

SOURCE Shanghai Henlius Biotech, Inc.