Reviewed by Dr. Michael Payne, Providence Health Care
The WHO recommends an all oral bedaquiline based second line regimen for treatment of drug resistant (DR) tuberculosis (TB). However, the microbiological response to these second-line regimens, as compared to first line regimens, is not well known. In Haiti, subjects were enrolled with drug susceptible (DS) (n=31) and DR (n=23) TB, with their response to therapy being assessed with first-line (rifampin, isoniazid, ethambutol, pyrazinamide) or second-line (bedaquiline, pyrazinamide, levofloxacin, linezolid, clofazimine) regimens, respectively. They found that the early bactericidal activity of first and second line regimens was similar during the first two weeks of therapy, as determined by multiple culture methods. Additionally, the same percentage (77.8%) of subjects from the DS and DR cohorts converted to culture negative after two months of therapy. Despite DR patients presenting with more advanced disease, they displayed a similar microbiological response to therapy as subjects with DS TB receiving a first-line treatment regimen. This information may be used to inform future recommendations on duration of therapy for DR TB.
Reference: J Infect Dis. 2023 Dec 7:jiad564. https://doi.org/10.1093/infdis/jiad564