A multicenter phase II study of everolimus in patients with progressive unresectable adenoid cystic carcinoma

Background: The aim of this study was to examine the efficacy and safety of everolimus in patients with progressiveunresectable adenoid cystic carcinoma (ACC).Methods: Histologically confirmed ACC patients with documented disease progression within 12 months prior tothe study entry were eligible. Everolimus was given at a dose of 10 mg daily until progression or occurrence ofunacceptable toxicities. The primary endpoint was a 4-month progression-free survival (PFS).Results: A total of 34 patients were enrolled. The 4-month PFS probability was 65.5% (95% one-sided confidenceinterval [CI], 47.7 to infinity). Median PFS duration was 11.2 months (95% CI, 3.6 to 15.8). Complete or partial responsewas not achieved. Twenty-seven (79.4%, 95% CI, 63.2 to 89.6) patients showed stable disease (SD). Tumor shrinkagewithin SD criteria was observed in 15 patients (44.1%) and SD lasting 6 months was observed in 13 patients (38.2%).Four patients had disease progression. Among the 18 patients with both pre- and post-treatment (at 8 weeks) FDG-PETscans available, 8 patients (44.4%) showed a partial metabolic response, defined as a ≥25% reduction in maximumstandardized uptake values (SUVmax). The most common adverse events were stomatitis, anemia, asthenia, andleukopenia. No unexpected everolimus related toxicities were reported.Conclusions: Everolimus showed promising efficacy and good tolerability in progressive unresectable ACC.Trial registration: ClinicalTrials.gov identifier, NCT01152840.