The aim of this study was to estimate the effect of a high-fat, high-calorie meal on the single-dose pharmacokinetics (PK) of trametinib, a MEK inhibitor. The design of this 2 treatment, 2 period crossover, incomplete wash-out study was influenced by the subject population, long half-life and PK variability; 24 subjects were randomized to a single, oral 2 mg trametinib dose administered in a fed/fasted state, followed by 7 days of serial PK sampling. Period 2 PK parameters were adjusted based on residual Period 1 concentrations. Geometric least square mean ratios of fed:fasted were 0.30, 0.76, and 0.90 for corrected maximum concentration (Cmax), area under concentration-time curve from time 0 to last quantifiable sample (AUC(0–last)) and AUC from time 0 extrapolated to infinity (AUC(0–α)), respectively. Median half-life was 6.3 and 5.3 days for fed and fasted regimens, respectively. Uncorrected PK parameters were consistent with these results. Food delayed absorption and had a mean difference in time of maximum concentration (tmax) of 3.9 hours. Both oral trametinib doses were well-tolerated. Single-dose trametinib administration with food decreased the rate and, to a lesser degree, the extent of absorption, supporting the recommendation to administer trametinib 1 hour before or 2 hours after a meal.