Drug Interaction Report

MONITOR CLOSELY: Coadministration of loncastuximab tesirine with antineoplastic, immune-modulating, immuno- or myelosuppressive therapies may potentiate the risk of severe infections, myelosuppression, and/or other unintended additive immunosuppressive effects. Serious and fatal infections, including opportunistic infections, as well as myelosuppression, including neutropenia, thrombocytopenia, and anemia have been reported with the use of loncastuximab tesirine. Concomitant use may potentiate these risks. However, clinical data are not available.

MANAGEMENT: The safety and efficacy of loncastuximab tesirine use in combination with other immuno- or myelosuppressive agents have not been evaluated. Patients receiving loncastuximab tesirine should be monitored closely for the development of signs and symptoms of infection and/or myelosuppression. The manufacturers' recommendations and institutional protocols for dosage, treatment regimens, monitoring, and management of toxicities should be consulted.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of ruxolitinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits.

MANAGEMENT: Patients treated with ruxolitinib should avoid consumption of grapefruit, grapefruit juice, and any supplement containing grapefruit extract. Ruxolitinib may be administered with or without food.