A phase 2 study of neoadjuvant chemotherapy plus durvalumab in resectable locally advanced head and neck squamous cell carcinoma.

Background: Patients with locally advanced head and neck squamous cell cancer (HNSCC) are treated with surgery followed by adjuvant (chemo) radiotherapy or definitive chemoradiation, but recurrence rates are high. Immune checkpoint blockade improves survival in patients with recurrent/metastatic HNSCC; however, the role of chemo-immunotherapy in the curative setting is not established.

Methods: This phase 2, single-arm, multicenter study evaluated neoadjuvant chemo-immunotherapy with carboplatin, nab-paclitaxel, and durvalumab in patients with resectable locally advanced HNSCC. The primary end point was a hypothesized pathologic complete response rate of 50%. After chemo-immunotherapy and surgical resection, patients received study-defined, pathologic risk adapted adjuvant therapy consisting of either durvalumab alone (low risk), involved field radiation plus weekly cisplatin and durvalumab (intermediate risk), or standard chemoradiation plus durvalumab (high risk).

Results: Between December 2017 and November 2021, 39 subjects were enrolled at three centers. Oral cavity was the most common primary site (69%). A total of 35 of 39 subjects underwent planned surgical resection; one subject had a delay in surgery due to treatment-related toxicity. The most common treatment-related adverse events were cytopenias, fatigue, and nausea. Post treatment imaging demonstrated an objective response rate of 57%. Pathologic complete response and major pathologic response were achieved in 29% and 49% of subjects who underwent planned surgery, respectively. The 1-year progression-free survival was 83.8% (95% confidence interval, 67.4%-92.4%).

Conclusions: Neoadjuvant carboplatin, nab-paclitaxel, and durvalumab before surgical resection of HNSCC were safe and feasible. Although the primary end point was not met, encouraging rates of pathologic complete response and clinical to pathologic downstaging were observed.