Drug Interactions between bedaquiline and conivaptan

GENERALLY AVOID: Coadministration with potent inhibitors of CYP450 3A4 may increase the plasma concentrations of bedaquiline, which is primarily metabolized by CYP450 3A4 to its less active N-monodesmethyl metabolite, M2. In healthy volunteers, administration of bedaquiline (400 mg once daily for 14 days) in combination with ketoconazole (400 mg once daily for 4 days) increased bedaquiline peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) by 9%, 22% and 33%, respectively, compared to administration alone. The potential for increased risk of adverse reactions should be considered, including prolongation of the QT interval and liver enzyme and bilirubin elevations.

MANAGEMENT: The concomitant use of potent CYP450 3A4 inhibitors such as clarithromycin, cobicistat, conivaptan, delavirdine, nefazodone, telithromycin, and most protease inhibitors and azole antifungal agents given systemically for more than 14 consecutive days should generally be avoided during treatment with bedaquiline unless the benefit is anticipated to outweigh the risk. Appropriate clinical monitoring for bedaquiline-related adverse reactions is recommended if coadministration is required. ECG, serum electrolytes (potassium, magnesium, calcium), and liver function tests (ALT, AST, alkaline phosphatase, bilirubin) should be monitored before starting bedaquiline therapy and periodically during treatment in accordance with the product labeling. Hypokalemia, hypomagnesemia, and hypocalcemia must be corrected prior to bedaquiline administration. Bedaquiline should be interrupted in patients who develop clinically significant ventricular arrhythmia or a QTcF interval greater than 500 msec confirmed by repeat ECG. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope. Patients should also seek medical attention if they experience potential signs and symptoms of hepatotoxicity such as fever, rash, itching, anorexia, nausea, vomiting, fatigue, malaise, right upper quadrant pain, dark urine, pale stools, and jaundice.