Design: Systematic review and network meta-analysis of randomised trials
Population: Children and adolescents under 18 with TB infection or drug-susceptible TB contact, without HIV (11 studies)
Primary outcome: Active TB incidence, adherence and adverse reactions by regimen
Effect: 4HR vs 9H active TB RR 0.49 (0.32–0.76); 3HP, 4HR, 4R better adherence than 9H

A network meta-analysis gathered the randomised evidence on preventive TB treatment in children and adolescents without HIV — the contacts and infected children who need preventive therapy — comparing short regimens with the old standard of nine months of isoniazid (9H).

The short courses came out well. Four months of isoniazid–rifampicin (4HR) reduced active TB through five years against 9H (relative risk 0.49, 95% CI 0.32–0.76), and 4HR, three months of isoniazid–rifapentine (3HP) and four months of rifampicin (4R) all had better adherence than 9H. Among the short regimens, adverse reactions were more common with 3HP than with 4HR or 4R, and 4R had the fewest adverse reactions of all.

For India, where paediatric TB infection and household contact numbers are vast and completion of nine-month isoniazid is poor, this supports the move to short rifamycin-based regimens — and gives a basis for choosing between them: 4R or 4HR where tolerability is the priority.

Prefer a short regimen (4HR, 3HP or 4R) over 9 months of isoniazid for preventive TB therapy in children.
4 months of isoniazid–rifampicin reduced active TB versus 9 months of isoniazid (RR 0.49).
Short regimens had better completion than 9 months of isoniazid.
Among short courses, 4R had the fewest adverse reactions and 3HP the most.

Why it matters

It backs abandoning the hard-to-complete 9-month course and helps pick between the short regimens on adherence and side effects.

The statistics, in plain English

The network had disconnected loops and the certainty is not high, so the adherence and adverse-event rankings are clearer than the head-to-head efficacy; the RR of 0.49 for 4HR is a halving of active TB against the old standard.