Shanghai, China, June 6th, 2022 – Shanghai Henlius Biotech, Inc. (2696.HK) announced that an international randomized phase 3 study (ASTRUM-005) of HANSIZHUANG (serplulimab), an anti-PD-1 mAb independently developed by Henlius, as first-line treatment for extensive-stage small-cell lung cancer (ES-SCLC) has been orally presented at 2022 American Society of Clinical Oncology (ASCO) Annual Meeting. Serplulimab is the first China-developed anti-PD-1 mAb in first-line treatment of lung cancer that was presented orally at ASCO Annual Meeting. The leading principal investigator is Professor Ying Cheng from Jilin Cancer Hospital.
Professor Ying Cheng said, "ASTRUM-005 is the first and largest ES-SCLC international multi-center clinical study led by Chinese researchers for anti-PD-1 mAb. A total of 114 sites’ subjects were screened around the globe, with 31.5% being Caucasian. The study results demonstrated that serplulimab in combination with chemotherapy can significantly extend the median OS to 15.4 months when compared to the control group in first-line SCLC, gaining global recognition while leapfrogging immunotherapy treatment for SCLC patients.”
Mr. Jason Zhu, President of Henlius, said, "HANSIZHUANG is an innovative mAb independently developed by Henlius. Based on the large number of unmet clinical needs, the company has implemented a comprehensive first-line treatment strategy for lung cancer with multiple clinical trials. Previously, the NDA of HANSIZHUANG for the treatment of ES-SCLC has been accepted by NMPA, which makes HANSIZHUANG potentially the world’s first anti-PD-1 mAb for the first-line treatment of SCLC. We are hoping that the approval comes soon to mend the gap and bring a new treatment option to patients living with ES-SCLC. Going forward, we will proactively promote more clinical research, thereby benefiting more patients around the world."
ASTRUM-005 has set up a total of 128 sites in China, Turkey, Poland, Georgia, etc. and enrolled 585 subjects from 114 sites, among whom 31.5% were Caucasian. In December 2021, ASTRUM-005 had met its primary study endpoint of the overall survival (OS) in the interim analysis and demonstrated HANSIZHUANG with a manageable safety profile. The global clinical data lays a solid foundation for future applications across the world. ASTRUM-005 results are as follows:
Titile
Serplulimab, a novel anti-PD-1 antibody, plus chemotherapy versus chemotherapy alone as first-line treatment for extensive-stage small-cell lung cancer: An international randomized phase 3 study (Abstract No. 8505)
Study design
This randomized, double-blind, international, multicenter, 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.
Results
As of October 22, 2021, 585 eligible patients were randomized (serplulimab group, n=389; placebo group, n=196), with a median follow-up duration of 12.3 months. The median OS in the serplulimab group and the placebo group were 15.4 (95% CI 13.3–NE) and 10.9 (95% CI 10.0–14.3) months, respectively, with a hazard ratio (HR) of 0.63 (95% CI 0.49–0.82; p<0.001). The 24-month OS rate in the two treatment groups were 43.1% and 7.9%, respectively. Median PFS assessed by the independent radiology review committee (IRRC) per RECIST v1.1 was 5.7 months in the serplulimab group and 4.3 months in the placebo group (HR 0.48, 95% CI 0.38–0.59). Efficacy improvements were also observed in ORR (80.2% vs. 70.4%) and DOR (median, 5.6 vs. 3.2 months) as assessed by IRRC per RECIST v1.1.
Grade ≥3 treatment related adverse events (TRAEs) related to serplulimab or placebo were reported by 129 (33.2%) and 54 (27.6%) patients in the respective groups. Incidence of immune-related adverse events (irAEs) was higher in the serplulimab group compared to the placebo group (37.0% vs. 18.4%), and was similar to the approved PD-1/PD-L1 antibodies.
Conclusions
The results demonstrated that serplulimab in combination with carboplatin-etoposide significantly improved OS as first-line treatment in ES-SCLC patients. The safety profile was consistent with previous studies. Serplulimab, as the first anti-PD-1 antibody showing OS benefit in untreated ES-SCLC patients, possess the potential to provide an alternative treatment option for this patient population worldwide.