Evaluation of a Modified Short all oral Treatment Regimen for Rifampicin-Multidrug Resistant Tuberculosis in Dominican Republic

Abstract Background This study aims to evaluate the effectiveness, safety, and impact on health-related quality of life (HQoL) of a fully oral shortened regimen for Rifampicin-Resistant/Multidrug-Resistant Tuberculosis (RR/MDR-TB) over 9 to 12 months under programmatic conditions. Methods A prospective cohort study was conducted on an all-oral modified Shortened Treatment Regimen (mSTR) comprising linezolid (Lzd), bedaquiline (Bdq), levofloxacin (Lfx), clofazimine (Cfz), and cycloserine (Cs). Patients with RR/MDR-TB were enrolled between January and December 2022 across seven drug-resistant TB units in the Dominican Republic. Results A total of 113 patients were enrolled, with 87% achieving culture conversion at two months. Treatment outcomes revealed that 79% of patients were successfully treated and didn’t relapse six months after the end of the treatment, 14% were lost to follow-up during the treatment, 6% deceased, and one experienced treatment failure due to Adverse Drug Reactions (ADRs). Adverse events (AEs) were common, with 82% of patients experiencing at least one AE with high proportion of QT interval prolongation, elevated transaminases, and anemia. A total of 12% of the patients experiencing Serious Adverse Events (SAEs). Improvement in HQoL dimensions was noted throughout treatment, with the EQ-VAS score increasing by an average of 15.5 by treatment end. Conclusion The high treatment success rate of the 5-drug mSTR facilitated the adaptation and integration of a shortened treatment regimen lasting 9 to 12 months in routine care in Dominican Republic. Although AEs were frequent, they were manageable in most cases. Continuous monitoring, especially regarding Lzd and Bdq use, is crucial to effectively mitigate risks. Since September 2023, this short all oral treatment regimen is now the one recommended for RR/MDR-TB patients in Dominican Republic.