The effect of food on the bioavailability of panobinostat, an orally active pan-histone deacetylase inhibitor, in patients with advanced cancer

Panobinostat is a novel oral pan-deacetylase inhibitor with promising anti-cancer activity. The study aimed to determine the influence of food on the oral bioavailability of panobinostat. This multicenter study consisted of a randomized, three-way crossover, food-effect study period (cycle 1) followed by single-agent panobinostat continual treatment phase in patients with advanced cancer. Patients received panobinostat 20 mg twice weekly, and panobinostat pharmacokinetics was investigated on days 1, 8, and 15 with a randomly assigned sequence of three prandial states (fasting, high-fat, and normal breakfast). Thirty-six patients were assessed for the food effect on pharmacokinetics and safety in cycle 1, after which 29 patients continued treatment, receiving single-agent panobinostat. Safety and antitumor activity were assessed during the extension period. Panobinostat systemic exposure was marginally reduced (14-16%) following food [geometric mean ratio (GMR) of the AUC(0-a)/high-fat breakfast/fasting, 0.84 (90% confidence interval {CI}, 0.74-0.96); normal breakfast/fasting, 0.86 (90% CI, 0.75-1.00)], and interpatient variability (coefficient of variation, 59%) remained essentially unchanged with or without food. Panobinostat C (max) was reduced by 44% (high-fat) and 36% (normal) with median T (max) prolonged by 1-1.5 h following food. Panobinostat was well tolerated, with thrombocytopenia, fatigue, nausea, and vomiting as common adverse events, and demonstrated antitumor activity with one patient with a partial response and six patients with stable disease as best response. Food produced minor changes in oral panobinostat exposure; thus, panobinostat can be given without regard to food intake in future clinical studies.