Dr Tao on the Efficacy of Avelumab/Cetuximab/Radiotherapy in Cisplain-Eligibile vs Ineligible HNSCC

Yungan Tao, MD, radiation oncologist, Department of Radiotherapy, Gustave Roussy Institute; president elect, GORTEC - French Head and Neck Oncology Radiotherapy Group, discusses the efficacy of avelumab (Bavencio) plus cetuximab (Erbitux) and radiotherapy in cisplatin-fit vs -unfit patients with head and neck squamous cell carcinoma (HNSCC), according to data from the final analysis of the phase 3 GORTEC-REACH study (NCT02999087).

Previously reported data from the study showed that the addition of an immune checkpoint inhibitor to cetuximab plus radiotherapy did not improve progression-free survival (PFS) vs standard-of-care (SOC) intensity-modulated radiation therapy (IMRT) plus cisplatin in this patient population, failing to meet the study's primary end point, Tao explains.

According to results presented at the 2024 ESMO Congress, a favorable PFS benefit (adjusted HR, 0.80; 95%CI 0.60-1.06) and low distant metastasis rate (subHR 0.24; 95%CI 0.11-0.49) was observed with the addition of avelumab to cetuximab plus radiotherapy in patients unfit for cisplatin. However, the regimen did not confer superior overall survival (OS) vs the SOC in this population (HR 1.05, 95% CI 0.76-1.44). At a median follow-up of 47.7 months (IQR 39.4-56.0), 4-year PFS rate was 33.7% (95% CI, 26.2%-42.2%) with the avelumab regimen vs 18.4% (95% CI,12.5%-26.1%) with the SOC. Respective 4-year OS rates were 42.6% (95% CI, 34.3%-51.3%) vs 39.4% (95% CI, 30.8%-48.7%).

Conversely, PFS (HR, 1.40; 95% CI, 1.07-1.82; P = .013), loco-regional progression (subHR, 2.26; 95% CI, 1.59-3.22), and OS (HR, 1.43; 95% CI, 1.05-1.93; P = .021) outcomes were inferior with avelumab plus cetuximab and radiotherapy vs the SOC, although potential improvement in the progression of distant metastases was observed (subHR=0.63; 95% CI, 0.32-1.22). At a median follow-up of 50.8 months (IQR, 45.8-57.4), the 4-year PFS rates were 54.7% (95% CI, 47.8%- 61.4%) with the SOC vs 42.3% (95% CI, 35.7%-49.2%) with the avelumab regimen. Four-year OS rates in these respective groups were 67.1% (95% CI, 60.4%-73.2%) vs 55.1% (95% CI, 48.3%- 61.8%).