The role of chemotherapy in adenoid cystic carcinoma (ACC) is controversial because ACC is usually stable without chemotherapy and the lack of randomized trials. Here, we conducted the first randomized trial to evaluate the efficacy of axitinib as compared with observation in ACC.
In this multicenter, prospective phase II trial, we enrolled patients with recurrent or metastatic ACC whose cancer had progressed within the past 9 months. Patients were randomly assigned to either axitinib (5 mg twice daily) or observation at a 1:1 ratio. Crossover from observation to axitinib was permitted after progression. The primary endpoint was a 6-month progression-free survival (PFS) rate. The secondary endpoints included objective response rate (ORR), overall survival (OS), PFS, duration of response, and adverse events.
Sixty patients were allocated to the axitinib or observation group, with response evaluation conducted in 54 patients. With a median follow-up of 25.4 months, the 6-month PFS rate was 73.0% with axitinib and 23.0% with observation. Median PFS was longer in the axitinib arm (10.8 months vs. 2.8 months, P < 0.001). The ORR of axitinib was 0.0%, but the disease control rate was 100.0% with axitinib and 51.9% with observation. Median OS was not reached with axitinib, but was 27.2 months with observation (P = 0.226). The most frequently reported adverse events for axitinib were oral mucositis and fatigue.
In this first randomized trial in patients with ACC, axitinib significantly increased the 6-month PFS rate as compared with observation. (ClinicalTrials.gov number, NCT02859012)