The safety of modified, all-oral shorter tuberculosis regimens in Armenia.

Background: The implementation of modified, all-oral shorter regimens for treatment of rifampicin-resistant tuberculosis has started in Armenia since August 2020 under the conditions of operational research.

Objective: This study aims to evaluate the safety and effectiveness of shorter regimens.

Methods: We evaluated cumulative incidence rates of serious adverse events, adverse events of grade 3 and greater and events resulting in treatment modifications or suspension for 52 study participants.

Results: A new, different pattern of adverse events emerged compared with the previous evaluations of drug safety of treatment for rifampicin-resistant tuberculosis. Arthralgia (23.1%) and peripheral neuropathy (21.2%) took leading positions among the adverse events resulting in modifications of treatment. Some adverse events of interest (prolonged QT interval, elevated liver enzymes and anemia) remained relevant for the patients receiving new combinations of anti-TB drugs. The other adverse events (impaired hearing, acute kidney injury and hypokalemia) lost their significance for safety surveillance of rifampicin-resistant tuberculosis treatment. One unexpected serious adverse event (lymphoproliferative skin lesion) brought to a "failed treatment" outcome. The other serious adverse event was anemia.

Conclusion: The shorter regimens proved to be safe and effective for treatment of rifampicin-resistant tuberculosis, but proper follow-up of adverse events is necessary.