Abstract
Background
Optimal doses of first line drugs for drug-susceptible tuberculosis (DS-TB) treatment in children and young adolescents remain uncertain. We aimed to determine if children treated using WHO-recommended or higher doses of first-line drugs achieve successful outcomes and sufficient pharmacokinetic exposures.
Methods
Titles, abstracts, and full-text articles were screened. We searched Pubmed, EMBASE, CENTRAL, and trial registries from 2010 to 2021. We included studies in children <18 years, being treated for DS-TB with rifampicin, pyrazinamide, isoniazid, and ethambutol. Outcomes were treatment success rates and drug exposures. The protocol for the systematic review was preregistered in PROSPERO, CRD42021274222.
Results
Of 304 studies identified, 46 studies were eligible for full-text review and 12 and 18 articles were included for the efficacy and pharmacokinetic analysis, respectively. Of 1,830 children in cluded in the efficacy analysis, 82% had favourable outcomes (range 25%-95%). At WHO-recommended doses, exposures to rifampicin, pyrazinamide, and ethambutol were lower in children as compared to adults. Children ≤6 years have 35% lower AUC than older children (14.4 (9.9-18.8) vs 22.0 (13.8-30.1) μg.h/mL) and children with HIV (CWHIV) had 35% lower rifampicin AUC than HIV negative children (17.3 (11.4-23.2) vs 26.5 (21.3-31.7) μg.h/mL). Heterogeneity and small sample sizes were major limitations.
Conclusion
There is large variability in outcomes with an average 82% favourable outcomes. Drug exposures are lower in children than in adults. Younger children and CWHIV are underexposed to rifampicin. Standardization of pharmacokinetic paediatric studies and individual patient data analysis with safety assessment are needed to inform optimal dosing.
