Drug Interactions between abacavir / lamivudine / zidovudine and copanlisib

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of copanlisib. The proposed mechanism is inhibition of CYP450 3A4-mediated metabolism of copanlisib by certain compounds present in grapefruit. When a single 60 mg intravenous dose of copanlisib was administered to cancer patients in combination with the potent CYP450 3A4 and P-gp inhibitor, itraconazole (200 mg once daily for 10 days), mean copanlisib peak plasma concentration (Cmax) did not change but systemic exposure (AUC) increased by 53%. The interaction has not been studied with grapefruit juice. In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Increased exposure to copanlisib may increase the risk of adverse effects such as nausea, vomiting, diarrhea, stomatitis, hyperglycemia, hypertension, noninfectious pneumonitis, cutaneous reactions (e.g., exfoliative dermatitis, maculopapular rash), anemia, neutropenia, thrombocytopenia, and infections.

MANAGEMENT: Patients should avoid the consumption of grapefruit and grapefruit juice during treatment with copanlisib.

Food may have variable effects on the oral bioavailability of zidovudine. Fatty foods have been reported to decrease the rate and extent of zidovudine absorption following oral administration. In a study of 13 AIDS patients, mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of zidovudine were 2.8 and 1.4 times higher, respectively, in fasting patients than in those administered the medication with breakfast. In addition, variations in plasma zidovudine concentrations were increased when administered in the fed state. In another study of eight patients, the time to reach peak concentration (Tmax) was increased from 0.68 to 1.95 hours, and Cmax was reduced by 50% when zidovudine was administered with a liquid high-fat meal relative to fasting. Protein meals can also delay the absorption and reduce the Cmax of zidovudine, although the extent of absorption is not significantly affected. The clinical significance of these alterations, if any, is unknown. The product labeling states that zidovudine may be taken with or without food.