More than 90 years after it was first discovered, and despite being listed as an essential medicine by the World Health Organization (WHO) since 2007, the lifesaving diabetes drug, insulin, remains very expensive and beyond the reach of many people with type 1 and 2 diabetes who need it globally, say leading experts writing in The Lancet Diabetes & Endocrinology journal.

"Insulin access is a complex challenge," explains author Dr David Beran from the Geneva University Hospitals and University of Geneva in Switzerland. "A wide variety of issues affect access including the global insulin market being dominated by three multinational manufacturers; import duties and taxes affecting the price insulin is entering different counties; and mark ups in the public and private sectors that also make insulin expensive."1

The Review is the first stage of the study, 'Addressing the Challenge and Constraints of Insulin Sources and Supply (ACCISS)', being led by Health Action International in collaboration with Boston University's School of Public Health and the Geneva University Hospitals and University of Geneva2. The ACCISS Study is a comprehensive and pioneering approach to gain a greater understanding of the complexity and challenges of poor access to insulin and enable countries to develop a tailored solution to address the challenge.

Insulin is essential for people with type 1 diabetes to stay alive and is needed by around a quarter of people with type 2 diabetes to control blood sugar.

With just three multinational companies having a near monopoly on the market, competition has been limited and impacted the price of insulin. Access and affordability to insulin is a challenge in both high-income settings, such as the USA, where the medicine can cost up to US$400 a month, as well as in sub-Saharan Africa, where the life expectancy of a child with type 1 diabetes is just 1 year because of poor access to affordable insulin.

Over the last decade, there has also been a record rise in the use of analogue (synthetic) insulin which now makes up two-thirds of all insulin used in high-income countries, adding to rises in cost. "We have seen a trend in the insulin market with animal insulin disappearing and being replaced by human insulin. A concern is whether a similar trend in which human insulin is replaced by analogue will occur,"1 explains Beran. The authors note that this trend exists despite a 2011 report by the WHO's 17th Expert Committee on the Selection and Use of Essential Medicines that found no evidence that the more costly analogue forms work better than the cheaper, older insulin.

Increased costs of insulin for health systems are due to this increasing use of analogue insulin as well as increasing numbers of people using insulin. In the UK, for example, the number of people using insulin trebled between 1991 and 2010, mainly due to a large increase in the number of people with type 2 diabetes using the drug. Between 2000 and 2010, the UK NHS paid out an astounding £2732 million on insulin. The key driver of this expenditure was the spiraling use of analogue insulin that rose from £18.2 million, or 12% of the total in 2000, to £305 million or 85% of the total in 2010.

According to the authors, over half of active patents on insulin are linked to the delivery pen devices and not the insulin itself, so intellectual property is not a barrier to entry in the market. "Although patents on the first analogue insulin expired in 2014, these newer forms are harder to copy. Unlike antiretrovirals and other chemical drugs, lengthy approval processes and the numerous procedures involved in making an exact copy of the biological product drive up the costs of making generic or biosilmilar versions of insulin. It can cost hundreds of millions of pounds to bring a new drug to market,"1 explains Richard Laing, co-author and Professor of international health at Boston University's School of Public Health in the USA.

"Addressing the challenges and constraints of insulin supply will require interventions to be tailored to individual countries. Some lower-income countries, like Nicaragua, are doing very well at providing insulin for free for its population, while other countries, such as Mali are charging high prices for it even in the public sector,"1 says Beran.

The authors hope that this Review will raise awareness of the issue and inspire action. Co-author Margaret Ewen from Health Action International in Amsterdam, The Netherlands, explains, "The issue of access to insulin lacks a global voice and global mobilization of resources. Over the past three decades, HIV/AIDS has attracted global attention with civil society truly getting behind the issue of universal access to antiretrovirals. The lessons from the successful treatment of HIV/AIDS need to be applied to ensure universal access to insulin."1