Drug Interaction Report

Coadministration with inhibitors of CYP450 3A4 may increase the plasma concentrations of asciminib. According to the prescribing information, asciminib is metabolized by CYP450 3A4-mediated oxidation and uridine diphosphate glucuronosyl transferase (UGT) 2B7- and 2B17-mediated glucuronidation. When a single 40 mg dose of asciminib was coadministered with clarithromycin, a potent CYP450 3A4 inhibitor, asciminib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 19% and 36%, respectively. However, no clinically significant differences in the pharmacokinetics of asciminib were observed when coadministered with itraconazole, another potent CYP450 3A4 inhibitor. Clinically significant interactions are not expected with mild or moderate CYP450 3A4 inhibitors.

MONITOR: Ethanol may increase folic acid elimination and folic acid absorption is decreased in chronic alcoholics. Excessive alcohol consumption may lead to folate deficiency.

MANAGEMENT: Monitoring of patient response to folic acid supplementation if they also consume alcohol regularly may be recommended.

ADJUST DOSING INTERVAL: Administration with food may increase the absorption of calcium. However, foods high in oxalic acid (spinach or rhubarb), or phytic acid (bran and whole grains) may decrease calcium absorption.

MANAGEMENT: Calcium may be administered with food to increase absorption. Consider withholding calcium administration for at least 2 hours before or after consuming foods high in oxalic acid or phytic acid.

ADJUST DOSING INTERVAL: Food may reduce the oral bioavailability of asciminib. When a single 40 mg dose of asciminib was administered with a low-fat meal (400 calories; 25% fat) in healthy volunteers, asciminib peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 35% and 30%, respectively, compared to asciminib administered in the fasted state. Administration with a high-fat meal (1000 calories; 50% fat) decreased the Cmax and AUC of asciminib by 68% and 62%, respectively.

MANAGEMENT: To ensure adequate asciminib exposures, food consumption should be avoided for at least 2 hours before and 1 hour after taking asciminib.