Drug Interactions between bedaquiline and lurbinectedin

GENERALLY AVOID: Grapefruit and Seville oranges may increase the plasma concentrations of lurbinectedin. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit and Seville oranges. Inhibition of hepatic CYP450 3A4 may also contribute. The interaction has not been studied with grapefruit or Seville oranges, but pharmacokinetic data are available for potent and moderate CYP450 3A4 inhibitors. In a clinical drug interaction study, coadministration of itraconazole, a potent CYP450 3A4 inhibitor, increased the systemic exposure (AUC) of total lurbinectedin by 2.7-fold and unbound lurbinectedin by 2.4-fold. In a Phase 1 study, coadministration of aprepitant, a moderate CYP450 3A4 inhibitor, decreased lurbinectedin plasma clearance by 33% compared to lurbinectedin alone. In general, the effect of grapefruit and Seville oranges is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice and Seville oranges (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. Increased exposure may increase the incidence and severity of adverse reactions of lurbinectedin, such as myelosuppression and hepatotoxicity.

MANAGEMENT: Patients should avoid consumption of grapefruit, grapefruit juice, and Seville oranges during treatment with lurbinectedin.

ADJUST DOSING INTERVAL: Food enhances the oral bioavailability of bedaquiline. When administered with a standard meal containing approximately 22 grams of fat (558 total Kcal), the relative bioavailability of bedaquiline increased by approximately 2-fold compared to administration under fasted conditions.

GENERALLY AVOID: Coadministration with alcohol may increase the risk of hepatotoxicity associated with the use of bedaquiline. In clinical trials, hepatic adverse drug reactions developed in more bedaquiline-treated patients than in those who received other drugs used to treat tuberculosis. In patients receiving bedaquiline or placebo in combination with other drugs used to treat multidrug-resistant tuberculosis, reversible aminotransferase elevations of at least 3 times the upper limit of normal developed more frequently in the bedaquiline treatment group [10.8%] than in the placebo group [5.7%].

MANAGEMENT: To ensure maximal oral absorption, bedaquiline should be taken with food. Patients should avoid alcohol use during treatment.