Results of a phase II randomized controlled clinical trial comparing efficacy of cabazitaxel versus docetaxel as second-line or above therapy in recurrent head and neck cancer.

Abstract

6018 Background: Cabazitaxel has shown activity in squamous cancer cell lines and in taxane resistant cell lines. Hence we planned a randomized phase 2 study to evaluate the efficacy and safety of cabazitaxel against docetaxel in recurrent head and neck cancer, post first line treatment. Methods: This was a phase 2 open label, investigator initiated, randomized controlled trial of Docetaxel (75 mg/m2) versus Cabazitaxel (20 mg/m2), in adult patients with head and neck cancer, ECOG performance status 0-2, with measurable disease, who have been exposed to at least one line of chemotherapy (CTRI/2015/06/005848). 1:1 central randomization was performed and chemotherapy was administered till progressive disease or until patient had intolerable side effects. The sample size of 92 (46 per group) was determined based on an assumption for a difference in disease control rate of 25%, an alpha of 0.05 and 80% power. The data was censored for analysis on 3rd March 2017. Primary analysis of disease control at 6 weeks (CR/PR/SD) was assessed and compared using the chi-square test. Progression free survival (PFS) and overall survival (OS) curves were estimated using the Kaplan-Meier method. Cox proportional hazard model was used for comparison of PFS and OS between the 2 arms. Results: 92 patients were accrued in the study with 46 in each arm. The disease control rate at 6 weeks was better in the docetaxel arm which was statistically significant over the cabazitaxel arm (13.6% versus 52.3%, p = 0.017). The median PFS was 21 days (95% CI 5.28-36.72 days) in the cabazitaxel arm versus 61 days (95% CI 16.21 to 105.79 days) in the docetaxel arm (HR = 1.466, 95% CI 0.923-2.328, p = 0.105). The median OS was 172 days (95% CI 111.78 to 232.22 days) in the cabazitaxel arm versus 188 days (95% CI 134.4 to 241.6 days) in the docetaxel arm (HR-1.408, 95% CI 0.738-2.688, p = 0.299). Conclusion: In this phase 2 study, docetaxel had a superior disease control rate at 6 weeks and PFS compared to cabazitaxel. Clinical trial information: CTRI/2015/06/005848.