Efficacy and safety of regimens for drug-resistant tuberculosis

[...]only three of the ten cohorts had follow-up data on relapse.4 It seems reasonable to suppose that good outcomes are possible using either a longer or a shorter regimen and, consequently, based on the data available to date, to allow cautious use of the 9-11 month regimen. Programmes treating large numbers of patients co-infected with HIV and MDR tuberculosis should note that the data are very scarce in this population, although this situation should improve with the publication of STREAM's results.9 Where there are no data on the prevalence of pyrazinamide resistance, programmes should also proceed with caution given recent data describing widespread genotypic resistance to pyrazinamide in patients with MDR tuberculosis in several countries.11 An important safety consideration is the recommended dose of moxifloxacin; by contrast with the cohorts included in the WHO comparison, which used either gatifloxacin or the standard dose of moxifloxacin, WHO are recommending higher weight-adjusted doses4 about which the data are very scarce.