Drug Interactions between abiraterone and brincidofovir

ADJUST DOSING INTERVAL: Food may significantly increase the oral bioavailability of some formulations of abiraterone acetate. Compared to administration in the fasted state, abiraterone peak plasma concentration (Cmax) and systemic exposure (AUC) were approximately 7- and 5-fold higher, respectively, when a single dose of abiraterone acetate was administered with a low-fat meal (7% fat; 300 calories) and approximately 17- and 10-fold higher, respectively, when it was administered with a high-fat meal (57% fat; 825 calories). Given the normal variation in the content and composition of meals, taking abiraterone acetate with meals has the potential to result in increased and highly variable exposures. The safety of these increased exposures during multiple dosing has not been assessed. However, the abiraterone acetate 125 mg tablet, commonly marketed as Yonsa, was found to have an approximately 6.5-fold higher Cmax and 4.4-fold higher AUC when a single dose of 500 mg (4 tablets) was administered with a high-fat meal (56% - 60% fat, 900 - 1000 calories) compared to overnight fasting in healthy volunteers. These differences were not considered clinically significant for this formulation.

MANAGEMENT: Some formulations of abiraterone acetate must be taken on an empty stomach. No food should be consumed for at least two hours before and one hour after the abiraterone acetate dose. However, the abiraterone acetate 125 mg tablet, commonly marketed as Yonsa, can be taken with or without food. The manufacturer's product labeling should be consulted for specific guidance.

ADJUST DOSING INTERVAL: Administration with food decreases the oral bioavailability of brincidofovir. According to the product labeling, administration of brincidofovir tablets with a low-fat meal (approximately 400 calories, 25% of calories from fat) was associated with a reduction in the systemic exposure (AUC) and peak plasma concentration (Cmax) of brincidofovir by 31% and 49%, respectively, compared to administration under fasting. However, no clinically meaningful changes in intracellular concentrations of cidofovir diphosphate were observed. The effect of food on the oral suspension formulation has not been evaluated.

MANAGEMENT: Brincidofovir oral tablets and suspension should be taken on an empty stomach. If necessary, the oral tablets may be taken with a low-fat meal.