LBA3 - First-line HLX07 vs. placebo combined with serplulimab and chemotherapy for nasopharyngeal cancer: A randomised, double-blind, multicentre phase II study

Background

High epidermal growth factor receptor (EGFR) expression is found in nearly 85% of NPC cases and is associated with poor outcomes. This study aims to compare the efficacy of HLX07 (a novel humanised anti-EGFR antibody) versus placebo, in combination with serplulimab (anti-PD-1 antibody) and chemotherapy as first-line treatment for R/M-NPC.

Methods

This is a randomised, double-blind, multicentre phase 2 study. Patients with pathohistologically confirmed, unresectable, recurrent or metastatic NPC that is not amenable to local or radical treatment and had no prior systemic therapy are randomized 2:1 to receive intravenous HLX07 (1000 mg) or placebo once every 3 weeks (Q3W). Serplulimab (300 mg), and chemotherapy (gemcitabine and cisplatin) were also given Q3W for up to 2 years, and 6 cycles, respectively. The primary endpoint is independent radiological review committee (IRRC)-assessed objective response rate (ORR) per the RECIST version 1.1. Secondary endpoints include other efficacy endpoints, safety, pharmacokinetics and biomarker explorations.

Results

By the data cutoff date of September 06, 2024, 75 patients were randomised to receive HLX07 (n=50) or placebo (n=25), combined with serplulimab and chemotherapy. Median follow-up duration was 10.8 months. A trend of a progression-free survival (PFS) benefit was observed for the HLX07 group compared to the placebo group (IRRC-assessed median PFS: not reached [NR] vs. NR; stratified HR 0.74, 95% CI 0.33-1.66). The 12-month PFS rate was 63.0% and 52.8% for the respective groups. IRRC-assessed confirmed ORR was 72.0% for the two groups. A trend of an improved median duration of response was also observed for the HLX07 group (median: NR vs. NR; stratified HR 0.56, 95% CI 0.22-1.43). Serious treatment-related adverse events occurred in 14 (28.0%) patients in the HLX07 group, and 8 (32.0%) in the placebo group.

Conclusions

The addition of HLX07 to serplulimab and chemotherapy showed preliminary efficacy along with a manageable safety profile. This treatment regimen warrants further investigation as a potential first-line option for R/M-NPC patients.

Clinical trial identification

NCT05513573 (released on 24 August 2022).

Editorial acknowledgement

Abstract writing support was provided by Zhi Hao Kwok, and Chen Hu of Shanghai Henlius Biotech, Inc.

Legal entity responsible for the study

Shanghai Henlius Biotech, Inc.

Funding

Shanghai Henlius Biotech, Inc.

Disclosure

H. Ni, Q. Wang, H. Yu, J. Li: Financial Interests, Institutional, Full or part-time Employment: Shanghai Henlius Biotech, Inc. All other authors have declared no conflicts of interest.