Rational use of moxifloxacin for tuberculosis treatment.

Despite intensifi ed eff orts in recent years, tuberculosis is uncontrolled in many regions. 1 Although drug-susceptible tuberculosis is a treatable disease, the 6 month duration of therapy, often administered under daily direct observation, can result in poor outcomes because of the demands that this regimen places on patients and health systems. Therapy for multidrug-resistant (MDR) tuberculosis is even more demanding: it lasts 2 years and is associated with distressing and often severe side-eff ects. 2 Unsurprisingly, treatment outcomes for MDR tuberculosis are considerably poorer than for drug-susceptible tuberculosis, even in optimum conditions. 3 After decades of neglect, eff orts to develop new drugs against tuberculosis have revived. Thanks to the Global Alliance for TB Drug Development (TB Alliance) and a few pharmaceutical companies, at least seven new chemical entities are in clinical development. In view of the urgent need for new drugs to treat drug-susceptible and drug-resistant tuberculosis, a pressing question for researchers, policy makers, and clinicians is, should new tuberculosis drugs be prioritised for the treatment of drug-susceptible or drug-resistant tuberculosis? The importance of this question is emphasised by the case of moxifl oxacin, a newer generation fl uoroquinolone. This drug is being trialled in a fi rst-line regimen that aims to shorten the treatment of drug-susceptible tuberculosis, 4 and is increasingly used in the treatment of MDR and extensively drug resistant (XDR) tuberculosis. Moxifl oxacin is widely available in developed countries and commonly used for upper respiratory tract infections. On the basis of its effi cacy against Mycobacterium tuberculosis, 5 a phase 3 trial to assess the effi cacy of a 4-month fi rst-line regimen incorporating moxifl oxacin is underway. However, even if successful, a 4-month regimen is not expected to improve cure rates, reduce mortality, or reduce community transmission. There is also evidence to support the use of moxifl oxacin for treatment of drug-resistant tuberculosis. At present therapeutic options are scarce and outcomes are particularly poor in the presence of resistance to the most commonly used fl uoroquinolone, ofl oxacin. 3,6 Moxifl oxacin has en hanced antituberculosis activity compared with ofl oxacin, might be eff ective against isolates phenotypically resistant to ofl oxacin or ciprofl oxacin, 7,8 and has less potential to promote fl uoroquinolone resistance. 9–11 It has also improved outcomes for patients with XDR tuberculosis. 6 Although there are many reasons to incorporate moxifl oxacin into a fi rst-line regimen, there is also a …