The WHO's latest essential medicines list included 16 new cancer drugs – but how many more can be added without changing the nature of the list?

How many medicines can truly be described as essential? The World Health Organization, which has been updating its global list of essential medicines every two years since 1977, currently includes around 450 drugs. India, however, runs its own essential medicines list (EML) which contains around 900 drugs. That disparity has come under scrutiny in recent weeks as India debates expanding the price controls that already cover around half the drugs on its EML. 

The debate in India is a familiar one. On the one side is the National Pharmaceutical Pricing Authority, which sees price controls as a way to ensure that these essential drugs really are available to as much of the population as possible. On the other is much of the pharma industry, arguing that price controls are a blunt instrument that, by restricting the returns on drugs, risk reducing production and investment in future development. The widespread use of pharma price controls in Pakistan has in the past had precisely that effect. 

The WHO's EML is not directly linked with price controls. Instead it consists of a core list that contains the "minimum medicine needs for a basic healthcare system" and a complementary list of "essential medicines for priority diseases". Both are intended primarily as a guideline to healthcare payers and governments about which drugs they should consider as a priority for funding – because in effect it's a guarantee that the listed drugs are life-saving, safe and cost-effective. 

However, to meet the last of these criteria, the WHO does also put pressure on suppliers to ensure that EML drugs are "available at all times in adequate amounts and in appropriate dosage forms, at a price the community can afford". In other words, in return for priority funding, suppliers are under an obligation to keep prices as low as possible. That is par for the course for the 95 percent of EML drugs that are off-patent. But what about the five percent that are still patented? 

That issue became particularly apparent in the run-up to the 2015 revision of the WHO EML, when countries including India were lobbying for a long list of patented drugs to be put on the list. In the end the EML, for the first time, did include several groundbreaking new treatments for diseases such as hepatitis C, multidrug-resistant tuberculosis and cancer. Indeed, 16 new cancer drugs made the list, including treatments for breast cancer and leukaemia. 

Most of the pharma companies affected apparently welcomed the listing, with some of them using the opportunity to boast that they are producing essential drugs. But there were a few areas of controversy. One was the decision to keep the Roche cancer drug Avastin (bevacizumab) on the list as an off-label treatment for age-related wet macular degeneration, rather than listing Novartis's more expensive Lucentis (ranibizumab injection). Many also took the WHO's decision to list Sovaldi (sofosbuvir) as a direct rebuke to Gilead for the high prices it was asking for the hepatitis C drug, despite the company's generics programme which aids access in poorer countries. 

Such debates are going to become increasingly fraught in the years to come. With the next EML revision due in 2017, the EML is likely to expand to include more new patented drugs. With the disease profile of less-developed countries rapidly shifting towards non-communicable diseases such as cancer, such drugs are indeed becoming more essential. 

Nevertheless, with each revision the debate about cost-effectiveness, pricing and the long-term effect on R&D will become more difficult. Indeed, the debate will get closer and closer to that raging in many developed countries, where payers and suppliers argue over the benefits of a few months of life for a cancer patient. And with each controversial listing, the tolerance of pharma companies is going to be stretched. There may eventually need to be clearer guidelines which actually make explicit the pricing promises that the WHO's EML currently only hints at.

Cancer drugs added to the EML in 2015 

  • Anastrozole (class) 
  • ATRA 
  • Campto (irinotecan) 
  • Casodex (bicalutamide) 
  • Cisplatin Eloxatin (oxaliplatin) 
  • Fludara (fludarabine) 
  • Gemzar (gemcitabine) 
  • Glivec (imatinib) 
  • G-CSF 
  • Herceptin (trastuzumab) 
  • Levact (bendamustine) 
  • Leuprolide (class) 
  • Mabthera (rituximab) 
  • Navelbine (vinorelbine) 
  • Xeloda (capecitabine)

Ana Nicholls is chief healthcare analyst at the Economist Intelligence Unit