Medicines for cancers in children: The WHO model for selection of essential medicines.

Pressures to include more cancer medicines in the WHO Model List of Essential Medicines (EML) pose challenges for the Expert Committee responsible for recommending changes to the list. How do medicines for cancer fit within a definition of essential medicines as those meeting the priority health needs of the population? Will identifying a medicine as "essential" offer some leverage to improve access to effective cancer medicines in low and middle-income countries (LMICs)? The addition of a number of medicines for the treatment of cancers in children to the Model List of Essential Medicines for Children (EMLc) in 2011 provides important insights into previous Expert Committee decision-making and offers a platform for future deliberations. As combination chemotherapy is required for effective treatment of many malignancies, a disease-based approach makes more sense than an agent-based approach. Inadequate financing to purchase essential medicines is a reality in many LMICs, thus a consideration of health impact is central to decisions on the selection and procurement of medicines. Inclusion in national EMLs should identify medicines that have priority for procurement in the public sector. This article will discuss some of the factors taken into account by the Expert Committee in developing the WHO EMLc. We argue that the disease-based approach coupled with the assessment of the magnitude of the clinical benefit provides an appropriate approach for considering further additions of medicines for pediatric cancers and for the review of the adult cancer section of the Model List.