From trials to programmatic scale-up: treatment outcomes of rifampicin-resistant tuberculosis during transition to short oral regimens in Vietnam (2021-2022).

OBJECTIVES

Vietnam is a high tuberculosis (TB) and rifampicin-resistant TB (RR-TB) burden country. Different new RR-TB regimens were recommended in recent years. Locally-generated evidence about nationwide implementation of different RR-TB regimens is essential to inform national treatment guidelines.

METHODS

A retrospective cohort study of all patients with RR-TB treated nationwide in Vietnam from 2021 to 2022. Short treatment regimens (STR) were 9-11-month standardized 7-drug regimens with either bedaquiline (BDQ_STR) or an injectable drug (inj_STR), and a modified 9-11-month 5-drug regimen (m_STR). Long regimens were 18-20-month regimens for fluoroquinolone-susceptible RR-TB (long RR-TB) or fluoroquinolone-resistant RR-TB (long pre-extensively drug-resistant TB). With logistic regression we estimated predictors of unfavorable outcome.

RESULTS

Of 4814 patients with RR-TB, 71.2% had end-of-treatment success. Failure, death, lost-to-follow-up (LTFU) and not evaluated accounted for 3.6%, 7.8%, 13.3%, and 4.2%, respectively. Long RR-TB regimen had significantly higher unfavorable outcomes as compared to BDQ_STR (adjusted odds ratio [95% confidence interval] = 1.56 [1.32-1.84]). Among STR, inj_STR had the lowest success rate (71.8%) in comparison to BDQ_STR (76.2%) (adjusted odds ratio [95% confidence interval] = 1.23 [1.04-1.45]). However, the LTFU rate is still high in both BDQ_STR and inj_STR. Treatment with inj_STR or long RR-TB regimen, retreatment after LTFU, being male and aged ≥50 years were predictors of unfavorable RR-TB treatment outcomes.

CONCLUSIONS

During the transition from injectable-containing to all-oral short regimens, nationwide data showed 71.2% RR-TB treatment success in Vietnam. The wider use of STRs and addressing LTFU may further improve outcomes. More robust and better managed long regimens are needed for those not eligible for any STR.