The WHO 2018 guideline update promotes the use of optimal treatment regimens in all populations. Though new, more effective and better tolerated options with a higher genetic barrier to resistance are now available for adults, optimized treatment options for children lag significantly behind.

This fifth edition of the Optimal Formulary and Limited-use List supports the transition to optimal WHO-recommended regimens for infants and children, while giving due consideration to the rapidly evolving treatment landscape and the risks inherent in the uncertain timelines for paediatric drug development.