Drug Interactions between regorafenib and tovorafenib

Consumer information for this interaction is not currently available.

MONITOR CLOSELY: Coadministration of regorafenib and drugs that interfere with platelet function or coagulation may potentiate the risk of bleeding complications. Treatment with regorafenib is associated with a high frequency of hemorrhage and thrombocytopenia. In one study, the overall incidence of hemorrhage (grades 1 to 5) was 21% in regorafenib-treated patients compared to 8% in placebo-treated patients, and the incidence of thrombocytopenia was 41% versus 17%. Fatal hemorrhage occurred in 4 of 500 (0.8%) patients receiving regorafenib and involved the respiratory, gastrointestinal, or genitourinary tracts.

GENERALLY AVOID: Coadministration of regorafenib with strong UGT1A9 inhibitors such as mefenamic acid or diflunisal may theoretically increase systemic exposure to regorafenib.

MANAGEMENT: Concomitant use of other medications that interfere with platelet function or coagulation should be considered cautiously in patients treated with regorafenib. Close clinical and laboratory observation for bleeding complications is recommended during therapy. The INR should be monitored more frequently during coadministration of warfarin. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools. According to European labeling, concomitant use of regorafenib with mefenamic acid or diflunisal should be avoided.