Drug Interaction Report

MONITOR: The concomitant use of bone marrow depressants and sodium phosphate P-32 may have additive myelosuppressive effects.

MANAGEMENT: Patients should be monitored for excessive bone marrow suppression during treatment with sodium phosphate P-32. Sodium phosphate P-32 should not be used as part of a sequential treatment with a chemotherapeutic agent. Dose reductions of the other bone marrow depressants may be necessary. The manufacturer's labeling should be consulted for more specific recommendations for each agent involved. Patients should be advised to contact their physician if they develop signs and symptoms of myelosuppression such as pallor, dizziness, fatigue, lethargy, fainting, easy bruising or bleeding, or signs of infection such as fever, chills, sore throat, body aches, and other influenza-like symptoms.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of umbralisib. When a single oral dose of umbralisib was administered with a high-fat, high-calorie meal (approximately 917 calories; 171 calories from protein, 232 calories from carbohydrate, 502 calories from fat) in healthy subjects, umbralisib peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 115% and 61%, respectively, compared to administration under fasted conditions.

MANAGEMENT: Umbralisib should be administered with food at approximately the same time each day.