Essential medicines are still essential.

On Oct 21, WHO published the full report of the 20th Expert Committee on the Selection and Use of Essential Medicines, with its new WHO Model List of Essential Medicines (EML). The new list includes recently developed medicines for drug-resistant tuberculosis (bedaquiline and delamanid), a number of new cancer treatments (such as imatinib, rituximab, and trastuzumab), and, perhaps most controversially, new direct-acting antiviral drugs (DAA) for the treatment of hepatitis C (sofosbuvir, simeprevir, daclatasvir, ledipasvir, and ombitasvir). Several of these medicines are very expensive. For example, the new medicines to treat hepatitis C are priced up to US$95 000 per 12-week course of treatment, and their primary patents will only expire in 2024–30. Despite the ability of some payers and intermediaries to negotiate large discounts, even high-income countries are struggling to pay for broad access to these treatments. It is not the fi rst time that WHO has added expensive medicines to the Model List. In 2002, the agency included 12 antiretroviral medicines for HIV/AIDS that were patented in many countries, to focus global attention on a major global public health need and to stimulate interventions to expand access to these lifesaving medicines. These products were unaff ordable for almost all countries at that time. The new Model List now expands further into other therapeutic areas. The recent inclusion of new expensive medicines has raised many questions. Has the original concept of essential medicines lost its original relevance as a list of basic medicines for resource-constrained settings? Should the list include medicines not yet authorised by stringent regulatory authorities or not easily available? Should the list include medicines for off -label indications? Should the list automatically include any medicine mentioned in a WHO treatment guideline? Previous expert committees’ reports have provided some answers to these questions. For instance, in 2013 bevacizumab was included for the treatment of macular degeneration, on the basis of available evidence but in the absence of regulatory approval for that specifi c indication. In 2005, child-friendly formulations of zinc sulfate tablets were added, even though such dispersible dosage forms were not widely available at the time. For many years, the WHO Model List has been viewed by some as applicable only to resource-constrained settings, and was assumed to include only the most basic medicines. This is a profound misunderstanding. The same principle of a limited list of cost-eff ective services underpins the logic of managed care institutions, hospital formularies, and reimbursement lists. The idea of selecting a limited list of essential medicines applies in all countries and in a variety of settings. We therefore believe that the inclusion of the newly listed cancer treatments, as well as the much-needed options for drug-resistant tuberculosis, is consistent with the defi nition of essential medicines. In 2002, WHO decided that cost alone would not prevent a medicine from being listed, if other criteria of safety, effi cacy, and comparative cost-eff ectiveness were fulfi lled. Yet the 2015 decision to include a range of DAAs for hepatitis C introduces a new approach of listing several very eff ective medicines, rather than selecting a single regimen. According to the Expert Committee, “Inclusion on the EML of all DAAs proposed in the applications aims at promoting competition among available alternatives and allowing for the selection of optimal combination treatment regimens, which may or may not be existing fi xed-dose combinations”. The Committee also noted that WHO is working to promote the rapid