Paediatric drug optimization (PADO) exercises have been convened by the World Health Organization (WHO) for various diseases, demonstrating their potential and impact to accelerate access to optimal formulations in the context of fragmented small markets for medicines for children. The WHO Global Tuberculosis Programme has convened PADO-TB meetings since February 2019 (PADO-TB1), followed by an interim review of the PADO-TB1 priorities in September 2020. Optimization of paediatric TB medicines forms part of the key actions in the Roadmap towards ending TB in children and adolescents, third edition and contributes to the achievement of the targets for ending TB in children and adolescents set out at the second United Nations High-level Meeting on the Fight Against TB in 2023. Considering the latest WHO recommendations on drug-susceptible TB, drug-resistant TB and TB preventive treatment, recent developments in new TB medicines and formulations made available, results of clinical trials and studies, and advancements of key medicines in the TB R&D pipeline, WHO convened the second PADO-TB meeting (PADO-TB2) on 3–5 October 2023. This meeting report summarizes the proceedings, discussions and the main consensus-based outputs of the PADO-TB2 meeting: - PADO-TB2 priority list (priority formulations to be investigated/developed in the short term and essential formulations to be developed in the longer term) - PADO-TB2 watch list (promising candidates for investigation/development for children within 5–10 years) - Priority research questions.

It is estimated that one third of the world's population is infected with Mycobacterium tuberculosis (the bacterium that causes tuberculosis (TB)), and that each year, about 9 million people develop TB, of whom about 2 million die. Of the 9 million annual TB cases, about 1 million (11%) occur in children (under 15 years of age). Of these childhood cases, 75% occur annually in 22 high-burden countries that together account for 80% of the world's estimated incident cases. In countries worldwide, the reported percentage of all TB cases occurring in children varies from 3% to more than 25%. The Stop TB Strategy, which builds on the DOTS strategy developed by the World Health Organization (WHO) and the International Union Against TB and Lung Disease, has a critical role in reducing the worldwide burden of disease and thus in protecting children from infection and disease. The management of children with TB should be in line with the Stop TB Strategy, taking into consideration the particular epidemiology and clinical presentation of TB in children. These consensus guidelines were produced to help the National Tuberculosis Programmes on the management of tuberculosis in children.

The Paediatric Antituberculosis Drug Optimization (PADO-TB) meetings provide a forum for clinicians, researchers, financial and technical partners and other relevant key stakeholders to work together, to ensure that priority optimal paediatric formulations of TB medicines are investigated, developed and made available to children in a timely manner. After the first meeting (PADO-TB1) in February 2019, WHO hosted an interim review of the PADO-TB1 priorities. The review considered the latest WHO recommendations and other relevant developments since February 2019, such as results of clinical trials, results of pharmacokinetics and pharmacodynamics studies, new formulations available and advancements of key drugs in the TB research and development pipeline. The 4.5-hour virtual review was attended by more than 50 experts including clinicians, researchers, representatives of national TB programmes (NTPs) from high TB burden countries, community representatives, financial and technical partners, members of the Child and Adolescent TB Working Group and representatives from various international agencies, including WHO. This report summarizes the main developments presented for various TB medicines and the decisions taken with regard to the PADO-TB priority list.

The aim of this document is to provide guidance on how to undertake a paediatric drug optimization (PADO) exercise and identify key priority products for research and development. This guidance is for all technical units undertaking a PADO exercise, all stakeholders involved in PADO processes as well as interested organizations and experts involved in the research and development of therapeutics in the public and private sectors.

Tuberculosis (TB) strains with drug resistance (DR-TB) are more difficult to treat than drug-susceptible ones, and threaten global progress towards the targets set by the End TB Strategy of the World Health Organization (WHO). There is thus a critical need for evidence-based policy recommendations on the treatment and care of patients with DR-TB, based on the most recent and comprehensive evidence available. In this regard, the WHO consolidated guidelines on drug-resistant tuberculosis treatment fulfil the mandate of WHO to inform health professionals in Member States on how to improve treatment and care for patients with DR-TB. Between 2011 and 2018, WHO has developed and issued evidence-based policy recommendations on the treatment and care of patients with DR-TB. These policy recommendations have been presented in several WHO documents and their associated annexes, including the WHO treatment guidelines for multidrug- and rifampicin-resistant tuberculosis, 2018 update, issued by WHO in December 2018. The policy recommendations in each of these guidelines have been developed by WHO-convened Guideline Development Groups (GDGs), using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach to summarize the evidence, and formulate policy recommendations and accompanying remarks. The present Consolidated guidelines include a comprehensive set of WHO recommendations for the treatment and care of DR-TB, derived from these WHO guidelines documents. The consolidated guidelines include policy recommendations on treatment regimens for isoniazid-resistant TB (Hr-TB) and MDR/RR-TB, including longer and shorter regimens, culture monitoring of patients on treatment, the timing of antiretroviral therapy (ART) in MDR/RR-TB patients infected with the human immunodeficiency virus (HIV), use of surgery for patients receiving MDR-TB treatment, and optimal models of patient support and care.

This work contains updated and clinically relevant information about tuberculosis. It is aimed at providing a succinct overview of history and disease epidemiology, clinical presentation and the most recent scientific developments in the field of tuberculosis research, with an emphasis on diagnosis and treatment. It may serve as a practical resource for students, clinicians and researchers who work in the field of infectious diseases.

The goal of the Paediatric drug optimization for cancer exercise was to develop a PADO priority list of formulations to be prioritized with a time horizon of 3–5 years, and a PADO ‘watch list’ containing promising candidates for investigation and development for children with a time horizon of 5–10 years. The PADO–cancer exercise enables alignment between funders, procurers, market-coordination entities, researchers, innovators, generics manufacturers, product development partnerships and regulators on priority products to be investigated and developed, as well as increasing efforts to tackle challenges in access to cancer medicines in LMICs.

This 2011 update of Guidelines for the programmatic management of drug-resistant tuberculosis is intended as a tool for use by public health professionals working in response to the Sixty-second World Health Assembly's resolution on prevention and control of multidrug-resistant tuberculosis and extensively drug-resistant tuberculosis. Resolution WHA62.15, adopted in 2009, calls on Member States to develop a comprehensive framework for the management and care of patients with drug-resistant TB. The recommendations contained in these guidelines address the most topical questions concerning the programmatic management of drug-resistant TB: case-finding, multidrug resistance, treatment regimens, monitoring the response to treatment, and selecting models of care. The guidelines primarily target staff and medical practitioners working in TB treatment and control, and partners and organizations providing technical and financial support for care of drug-resistant TB in settings where resources are limited.

The development of paediatric medicines can be challenging since this is a different patient population with specific needs. A medicine designed for use in paediatric patients must consider the following aspects: patient population variability; the need for dose flexibility; route of administration; patient compliance; excipient tolerability. For example, the toxicity of excipients may differ in children compared to adults and children have different taste preferences. Globally, about 75% of drugs do not carry regulatory approval for use in children; worldwide, many medications prescribed for the treatment of paediatric diseases are used off-label, and less than 20% of package inserts have sufficient information for treating children. This book provides an update on both state-of-the-art methodology and operational challenges in paediatric formulation design and development. It aims at re-evaluating what is needed for more progress in the design and development of age-appropriate treatments for paediatric diseases, focusing on: formulation development; drug delivery design; efficacy, safety, and tolerability of drugs and excipients.