Tackling the threat of antimicrobial resistance in neonates and children: outcomes from the first WHO-convened Paediatric Drug Optimisation exercise for antibiotics.

Children and neonates are highly vulnerable to the impact of antimicrobial resistance. Substantial barriers are faced in relation to research and development of antibacterial agents for use in neonates, children, and adolescents aged yonger than 19 years, and focusing finite resources on the most appropriate agents for development and paediatric optimisation is urgently needed. In November and December, 2022, following the successes of previous similar disease-focused exercises, WHO convened the first Paediatric Drug Optimisation (PADO) exercise for antibiotics, aiming to provide a shortlist of antibiotics to be prioritised for paediatric research and development, especially for use in regions with the highest burden of disease attributable to serious bacterial infection. A range of antibiotics with either existing license for children or in clinical development in adults but with little paediatric data were considered, and PADO priority and PADO watch lists were formulated. This Review provides the background and overview of the exercise processes and its outcomes as well as a concise review of the literature supporting decision making. Follow-up actions to implement the outcomes from the PADO for antibiotics process are also summarised. This Review highlights the major beneficial influence the collaborative PADO process can have, both for therapeutic drug class and disease-specific themes, in uniting efforts to ensure children have access to essential medicines across the world.

WHO's essential medicines and AWaRe: recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections.

The WHO Model List of Essential Medicines (EML) prioritizes medicines that have significant global public health value. The EML can also deliver important messages on appropriate medicine use. Since 2017, in response to the growing challenge of antimicrobial resistance, antibiotics on the EML have been reviewed and categorized into three groups: Access, Watch, and Reserve, leading to a new categorization called AWaRe. These categories were developed taking into account the impact of different antibiotics and classes on antimicrobial resistance and the implications for their appropriate use. The 2023 AWaRe classification provides empirical guidance on 41 essential antibiotics for over 30 clinical infections targeting both the primary health care and hospital facility setting. A further 257 antibiotics not included on the EML have been allocated an AWaRe group for stewardship and monitoring purposes. This article describes the development of AWaRe, focussing on the clinical evidence base that guided the selection of Access, Watch, or Reserve antibiotics as first and second choices for each infection. The overarching objective was to offer a tool for optimizing the quality of global antibiotic prescribing and reduce inappropriate use by encouraging the use of Access antibiotics (or no antibiotics) where appropriate. This clinical evidence evaluation and subsequent EML recommendations are the basis for the AWaRe antibiotic book and related smartphone applications. By providing guidance on antibiotic prioritization, AWaRe aims to facilitate the revision of national lists of essential medicines, update national prescribing guidelines, and supervise antibiotic use. Adherence to AWaRe would extend the effectiveness of current antibiotics while helping countries expand access to these life-saving medicines for the benefit of current and future patients, health professionals, and the environment.

Paediatric medicine issues and gaps from healthcare workers point of view: survey results and a narrative review from the global accelerator for paediatric formulations project.

The WHO Model List of Essential Medicines for Children (EMLc) has not been systematically revised in the last few years. We conducted a survey addressed to healthcare professionals prescribing, preparing, or administering medicines to children and a narrative review to identify problematic paediatric formulations or missing medicines in all therapeutic fields to inform the review of the EMLc in 2023. A total of 285 physicians (63%), 28 nurses (6%) and 142 pharmacists (31%), mostly working in the hospital setting, reported at least one problematic medicine. 290 medicines were reported as missing (completely or the child-appropriate formulation). The top three most mentioned were ciprofloxacin together with phenobarbital and omeprazole. 387 medicines were reported as problematic (34% were oral liquid formulations, 34% tablets, 18% parenteral preparations. Mostly of the products were antibacterials (27%), cardiovascular medicines (11%) and antivirals (11%). The obtained responses show the perspective of healthcare workers working around the world, particularly in the European region (25%), in the African region (24%), and in the Region of the Americas (19%), with limited representation from Northern Africa and the Middle East. Our results need to be analysed with the outputs of other ongoing works before specific products can enter the WHO-hosted Global Accelerator for Paediatric formulations network prioritisation process. Efforts to develop appropriate formulations for children should be accelerated so that the uncertainties associated with off-label drug preparation and use are minimised, and therapeutic benefits are optimised.

Cancer medicines on the WHO Model List of Essential Medicines: processes, challenges, and a way forward.

The selection of cancer medicines for national procurement requires deliberate evaluation of population benefit, budget impact, sustainability, and health system capacity. However, this process is complicated by numerous challenges, including the large volume and rapid pace of newly developed therapies offering marginal gains at prohibitively high prices. The WHO Model List of Essential Medicines (EML) and Model List of Essential Medicines for Children (EMLc) have undergone a series of evidence-based updates to ensure recommended cancer medicines offer meaningful clinical benefit. This Health Policy paper describes how cancer medicines are listed on the EML and EMLc, including two updated WHO processes: (1) the formation of the Cancer Medicines Working Group, and (2) additional selection principles for recommending cancer medicines, including a minimum overall survival benefit of 4-6 months with improvement to quality of life compared with standard treatment. These updates, along with proposals to include formal price considerations, additional selection criteria, and multisectoral collaboration (eg, voluntary licensing) promote procurement of high-value essential cancer medicines on national formularies in the context of supporting sustainable health systems to achieve universal health coverage.

The WHO essential medicines list AWaRe book: from a list to a quality improvement system.

Antibiotics are often prescribed inappropriately, either when they are not necessary or with an unnecessarily broad spectrum of activity. AWaRe (AccessWatchReserve) is a system developed by WHO to classify antibiotics based on their spectrum of activity and potential for favouring the development of antibiotic resistance (Access: narrow spectrum/low potential for resistance; Watch: broader spectrum/higher potential for resistance; Reserve: last resort antibiotics to use very selectively). The WHO target is that by 2023, at least 60% of prescribed antibiotics globally should be from the Access category. The WHO AWaRe Book aims to improve empiric antibiotic prescribing by providing simple guidance for common infections based on the principles of AWaRe in alignment with the Model Lists of Essential Medicines for adults and children.

Assessing the Appropriateness of Formulations on the WHO Model List of Essential Medicines for Children: Development of a Paediatric Quality Target Product Profile Tool.

The World Health Organization's Model List of Essential Medicines for Children (EMLc) presents a list of the most efficacious, safe, and cost-effective medicines for priority conditions, intended for use in children up to 12 years of age. However, gaps in global availability and use of age-appropriate formulations of medicines for children still exist. To address these shortcomings, a comprehensive analysis of the appropriateness of formulations of essential medicines for children is being undertaken through the Global Accelerator for Paediatric Formulations (GAP-f) network, a WHO network launched in 2020 to respond to the paediatric treatment gap. This article describes the development and application of a paediatric Quality Target Product Profile (pQTPP) tool by WHO, to retrospectively evaluate the paediatric age-appropriateness of formulations on the EMLc and identify potential formulation gaps, to inform the review of the EMLc in 2023. A combination of paediatric-centric and global health-focused attributes and targets were defined, taking into consideration regulatory agency paediatric development guidelines and literature sources, and a qualitative scoring system was developed and tested. Example evaluations of paracetamol and clofazimine are provided, illustrating the tool's use. The assessment of EMLc formulations is ongoing and shortcomings and gaps in EMLc formulations have already been identified. The pQTTP tool may also be applied to national lists and prospectively when designing new paediatric formulations.

The "Square Box": Therapeutic Equivalence as a Foundation of the WHO Model List of Essential Medicines.

Every two years, the World Health Organization (WHO) updates its Model List of Essential Medicines, intended as a guide for countries to adopt or adapt in accordance with local priorities and treatment guidelines, for the development of national essential medicines lists. When more than one therapeutic option is available for a given indication, the WHO Model List often includes a single medicine as representative of a group of equivalent and interchangeable medicines. The representative medicine of that group is listed with an accompanying 'square box' symbol. The intended purpose of the square box is to highlight pharmacological classes or groups of medicines for which countries, institutions and health professionals can assume homogeneous therapeutic efficacy and safety and select the most appropriate single medicine based on price, local availability, and acceptability. Though this concept of therapeutic equivalence within a therapeutic class has been endorsed by most authoritative textbooks of pharmacology since Goodman & Gilman's The Pharmacological Basis of Therapeutics and evidence-based guidelines, marketing forces have often made claims on individual drugs to distinguish them beyond relevant differences shown by reliable evidence: this has generated the concept of "me-too drugs" with its double meaning-i.e., market latecomers differing minimally from products preceding them and whose marketing budgets have significant opportunity costs, or medicines which may be useful to substitute for equivalent products in the event of shortages. The square box concept is applied in the context of a comprehensive list: therapeutic equivalence or interchangeability cannot always be easily established. Different interpretations have been applied to different groups of medicines over the 40+ year history of the Model List. This paper presents the concept of the square box, provides key examples and guidance on how square box listings should be practically interpreted in the development and implementation of national essential medicine lists, considers the applicability of a square box listing concept to biologic medicines and proposes that an updated review of the square box concept and listings is warranted.