Drug Interaction Report

CONTRAINDICATED: Administration of intravesical BCG during immunosuppressant or intense antineoplastic therapy may be associated with a risk of disseminated infection due to enhanced replication of the BCG strain of Mycobacterium bovis in the presence of diminished immune competence. Deaths have been reported as a result of systemic BCG infection and sepsis. Patients may be immunosuppressed if they have recently received or are receiving alkylating agents, antimetabolites, radiation, some antirheumatic agents, high dosages of corticosteroids or adrenocorticotropic agents (e.g., greater than or equal to 2 mg/kg/day or 20 mg/day of prednisone or equivalent for 14 consecutive days or more), or long-term topical or inhaled corticosteroids. In addition, these patients may not develop an adequate immune response to BCG, which would reduce its anti-tumor efficacy.

MANAGEMENT: Use of intravesical BCG in immunosuppressed patients with congenital or acquired immune deficiencies, including those due to concurrent disease (e.g., AIDS, leukemia, lymphoma), cancer therapy (e.g., cytotoxic drugs, radiation) or immunosuppressive therapy (e.g., corticosteroids), is considered contraindicated. Clinicians should be aware that BCG may persist in the urinary tract for several months after BCG instillations, and delayed manifestations of disseminated BCG infection may develop months or years after BCG therapy. Patients who receive cancer or immunosuppressive therapy after BCG instillation may be at increased risk.

GENERALLY AVOID: Grapefruit juice may significantly increase the plasma concentrations of midostaurin. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. 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. Ketoconazole, a potent CYP450 3A4 inhibitor, has been shown to increase midostaurin systemic exposure (AUC) by greater than 10-fold in healthy volunteers. Increased exposure to midostaurin may increase the risk of adverse effects such as nausea, vomiting, diarrhea, edema, hyperglycemia, hyperuricemia, QT prolongation, neutropenia, lymphopenia, thrombocytopenia, and anemia.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of midostaurin. Relative to fasting conditions, midostaurin systemic exposure (AUC) increased by approximately 1.2-fold when administered with a standard meal (457 calories; 50 g fat, 21 g proteins, 18 g carbohydrates) and 1.6-fold when administered with a high-fat meal (1007 calories; 66 g fat, 32 g proteins, 64 g carbohydrates), while midostaurin peak plasma concentration (Cmax ) decreased by 20% and 27%, respectively.

MANAGEMENT: The manufacturer recommends taking midostaurin with food. Midostaurin was administered with food in clinical trials. Patients should avoid consumption of grapefruit and grapefruit juice during treatment with midostaurin.