Reply to Comments by Kakkar and Dahiya

Abstract

TO THE EDITOR: Chahine, Karaoui, and Mansour1 reviewed the efficacy and safety of bedaquiline in the treatment of adults with pulmonary multidrug-resistant tuberculosis (MDR-TB) and generally agree with the comments made by Kakkar and Dahiya.2 Bedaquiline was approved by the Food and Drug Administration based largely on results from phase 2 studies using sputum conversion as a surrogate marker for efficacy rather than long-term mortality data.2 Bedaquiline was shown to be associated with an unfavorable side effect profile, including an unexplained increased risk of mortality, QT prolongation, and elevated liver function tests.2 However, it is important to acknowledge that bedaquiline is the first novel drug to be approved for the treatment of TB in more than 4 decades and the communities devastated by MDR-TB are in desperate need for more options to manage their patients. Initial reports describing the use of bedaquiline in patients with MDR-TB and extensively drug-resistant TB are promising.3,4 Fortunately, the World Health Organization (WHO) has recently issued an interim policy guidance recommending that bedaquiline may be added to a WHO-recommended regimen in adult patients with MDR-TB when an effective regimen containing 4 second-line drugs in addition to pyrazinamide cannot be designed, and when there is documented evidence of resistance to any fluoroquinolone in addition to multidrug resistance.5 Similarly, the Centers for Disease Control and Prevention (CDC) has also issued provisional guidelines recommending that bedaquiline may be used for 24 weeks in adults with laboratory-confirmed pulmonary MDR-TB when an effective regimen cannot otherwise be provided; on a case-by-case basis in children, persons with HIV, pregnant women, persons with extrapulmonary MDR-TB, and patients with comorbidties when effective regimen cannot otherwise be provided; and on a case-by-case basis for durations longer than 24 weeks when an effective regimen cannot be provided.6 Both WHO and CDC emphasize the need for careful monitoring of patients on bedaquiline therapy for safety concerns.5,6

Until further data become available, the authors believe that patients who meet eligible criteria according to current guidelines may benefit from bedaquiline therapy with careful monitoring for potential side effects and drug interactions.