What are the possible interactions of Quizartinib with other drugs? What medications should be avoided?

Quizartinib is a targeted therapy drug mainly used to treat acute myeloid leukemia (AML) with FLT3 mutations. It inhibits the proliferation and survival of cancer cells by selectively inhibiting the activity of FLT3 receptor tyrosine kinase. However, like other anticancer drugs, interactions with other drugs may occur, and these interactions may affect the drug's efficacy or increase the risk of adverse effects.

Quizatinib is metabolized by the cytochromeP450 enzyme system in the liver, specifically CYP3A4. Therefore, any drug that affects CYP3A4 activity may interact with quizartinib. If you use CYP3A4 inhibitors (such as ketoconazole, itraconazole, diltiazem, etc.) at the same time, it may cause the concentration of quizartinib to increase in the body, thereby increasing the risk of side effects, such as hepatotoxicity, prolongation of the QT interval, etc. On the contrary, if it is used in combination with CYP3A4 inducers (such as carbamazepine, phenobarbital, St. John's wort, etc.), it may lead to a decrease in the blood concentration of quizartinib and weaken its efficacy.

Quizatinib has the side effect of QT interval prolongation. Therefore, special caution is required when using other drugs that also have QT prolongation effects (such as azithromycin, fluconazole, certain antipsychotic drugs, etc.). Concomitant use of these drugs may increase the risk of prolongation of the QT interval and increase the probability of arrhythmia.

Quizartinib may also interact with certain anticoagulant medications. Studies have shown that quizartinib may affect blood coagulation mechanisms, so if used in combination with oral anticoagulants such as warfarin, coagulation indicators may need to be monitored and the anticoagulant dose adjusted as needed.

Quizartinib may also interact with certain other chemotherapy drugs (such as cyclophosphamide) or immunosuppressive drugs (such as cyclosporine). These drugs may cause severe drug toxicity in patients by altering the metabolism of quizartinib or enhancing its side effects. Therefore, when using these drugs together, patients are advised to strictly monitor them under the guidance of a doctor.

Reference materials:https://go.drugbank.com/drugs/DB12874