Bedaquiline Drug Resistance Emergence Assessment in Multidrug-resistant-tuberculosis (MDR-TB) (DREAM) was a 5-year (2015-2019) drug-resistance surveillance study across 11 countries. This study demonstrates that resistance rates to bedaquiline are low for bedaquiline-treatment-naïve populations. There were no changes in resistance rates to bedaquiline over the 5 year study period. Co-resistance between bedaquiline, linezolid and clofazimine was rare. The study determined the susceptibility of 5036 MDR-TB isolates of bedaquiline-treatment-naïve patients to bedaquiline and other anti-tuberculosis drugs by the 7H9 broth microdilution (BMD) and 7H10/7H11 agar dilution (AD) minimal inhibitory concentration (MIC) methods. Of the 5036 MDR-TB isolates, bedaquiline-susceptible, intermediate and bedaquiline-resistant rates were 97.9%, 1.5% and 0.6%, respectively, for BMD, and 98.8%, 0.8% and 0.4% for AD. Resistance rates were: ofloxacin 35.1%, levofloxacin 34.2%, moxifloxacin 33.3%, 1.5% linezolid and 2% clofazimine. Cross resistance between bedaquiline and clofazimine was 0.4% in MDR-TB and 1% in pre-extensively drug-resistant (pre-XDR-TB)/XDR-TB populations. Co-resistance to bedaquiline and linezolid, and clofazimine and linezolid, were 0.1% and 0.3%, respectively, in MDR-TB, and 0.2% and 0.4% in pre-XDR-TB/XDR-TB populations.
Reference:
Koné Kaniga et al. Bedaquiline Drug Resistance Emergence Assessment in MDR-TB (DREAM): a 5-Year Prospective In-Vitro Surveillance Study of Bedaquiline and Other Second-Line Drug-Susceptibility Testing in MDR-TB Isolates. J Clin Microbiol. 2021 Oct 27;JCM0291920. doi: 10.1128/JCM.02919-20.