542P - First-line HLX07 plus serplulimab with or without chemotherapy versus serplulimab plus chemotherapy in advanced/recurrent squamous non-small cell lung cancer: A phase II study

Background

Adding PD-L1/PD-1 inhibitors to chemotherapy (chemo) has demonstrated efficacy and been approved for advanced squamous non-small cell lung cancer (sqNSCLC) as first-line therapy. However, the prognosis remains unsatisfactory. High expression of the epidermal growth factor receptor (EGFR) is prevalent in sqNSCLC. This study aimed to compare the efficacy of HLX07, a novel humanised anti-EGFR antibody, plus serplulimab (anti-PD-1 antibody) ± chemo versus serplulimab plus chemo as first-line option for advanced sqNSCLC.

Methods

This randomised, multicentre phase 2 study consisted of 4 parts and assessed different combinations of HLX07 (at various doses), serplulimab, and chemo. Part 3 explored the preliminary efficacy of the three-drug combination and is presented below. Patients with stage IIIB/IIIC or IV sqNSCLC that could not be treated with surgery or radiation therapy and had not received prior systemic therapy were enrolled and randomised 1:1 to receive intravenous HLX07 at 800 mg (group A) or 1000 mg (group B), combined with serplulimab (300 mg) and chemo (carboplatin and nab-paclitaxel), Q3W. The primary endpoints were IRRC-assessed ORR and PFS per RECIST 1.1.

Results

As of 27 June 2023, 12 patients were enrolled and randomly assigned to group A (n=6) and group B (n=6) in part 3. The median age was 64 years. 11 (91.7%) patients were male. 10 (83.3%) patients had stage IV disease. With a median follow-up of 3.5 months, investigator-assessed unconfirmed ORR per RECIST 1.1 was 83.3% (95% CI 35.9–99.6) in group A and 66.7% (95% CI 22.3–95.7) in group B. Disease control rate was 100.0% (95% CI 54.1–100.0) in both groups. 2 (33.3%) patients in group A and 1 (16.7%) in group B had serious treatment-emergent adverse events (TEAEs). 1 (16.7%) patient in group B reported a grade 3 adverse event of special interest (AESI) with dermatitis acneiform; no grade 4–5 AESI occurred. No TEAE leading to death was reported.

Conclusions

First-line HLX07 plus serplulimab and chemo conferred encouraging antitumour efficacy with a manageable safety profile in patients with advanced sqNSCLC and warrants further investigation.

Clinical trial identification

NCT04976647 (released on 26 July 2021).

Editorial acknowledgement

Editorial assistance was provided by Zhi Hao Kwok, Shiqi Zhong, and Chen Hu of Shanghai Henlius Biotech, Inc.

Legal entity responsible for the study

Shanghai Henlius Biotech, Inc.

Funding

Shanghai Henlius Biotech, Inc.

Disclosure

J. Feng, L. Wang, J. Li, Q. Wang, J. Zhu: Financial Interests, Personal, Full or part-time Employment: Shanghai Henlius Biotech, Inc. All other authors have declared no conflicts of interest.