The use of docetaxel as a radiosensitizer in patients with head and neck cancer unsuitable for cisplatin based chemoradiation: Landmark 3-year survival analysis of a randomized phase III trial (DHANUSH).

6086 Background: Patients with cisplatin-ineligible locally advanced head and neck squamous cell carcinoma (LA-HNSCC) have limited guideline-recommended treatment options. DHANUSH (CTRI/2017/05/008700), an open-label, phase II/III randomized controlled trial, was among the first studies to demonstrate superior disease-free survival (DFS) and overall survival (OS) in this patient population. Here, we present the 3-year landmark survival analysis update of our study cohort. Methods: This was a single-centre, open-label, randomized controlled phase II/III study conducted at our institute between July 2017 and May 2021. Cisplatin-ineligible patients with LA-HNSCC who were planned for definitive or adjuvant chemoradiation in the multidisciplinary joint clinic were enrolled. Patients were randomly assigned in a 1:1 ratio to receive either radiation therapy alone or concurrent weekly docetaxel (15 mg/m²) for up to seven cycles. The primary endpoint of the study was 2-year disease-free survival (DFS). Here, we present the 3-year landmark survival update, including disease-free (DFS) and overall survival (OS), as of January 25, 2025. Results: The study recruited 356 patients, with 179 receiving concurrent docetaxel and 177 receiving radiation therapy alone. The median follow-up for the entire cohort was 67.9 months (95% CI, 65.7–70.3). At the time of the median follow-up, 123 deaths occurred in the concurrent docetaxel arm compared to 136 deaths in the radiation therapy alone arm. The median DFS in the concurrent docetaxel arm was 11.9 months (95% CI, 8.3–21.7) compared to 5.9 months (95% CI, 4.9–8.2) in the radiation therapy alone arm (p = 0.003). Similarly, the median OS was 23.1 months (95% CI, 17.4–30.6) in the concurrent docetaxel arm versus 15.3 months (95% CI, 13.9–22.3) in the radiation therapy alone arm (p = 0.048). The 3-year DFS was 36.3% (95% CI, 29.9–44.1) in the concurrent docetaxel arm versus 23.2% (95% CI, 17.7–30.3) in the radiation therapy alone arm. Similarly, the 3-year OS was 40.2% (95% CI, 33.7–48.1) in the concurrent docetaxel arm compared to 28.8% (95% CI, 22.9–36.3) in the radiation therapy alone arm. Conclusions: The addition of concurrent docetaxel to radiation therapy significantly improved survival outcomes (DFS and OS) in cisplatin-ineligible LA-HNSCC patients at the 3-year survival landmark. Clinical trial information: CTRI/2017/05/008700 .