The world's most neglected diseases

Infectious diseases can be considered “neglected” when there is a lack of effective, affordable, or easy to use drug treatments. As most patients with such diseases live in developing countries and are too poor to pay for drugs, the pharmaceutical industry has traditionally ignored these diseases. Over the past decade, however, the public sector, by creating favourable marketing conditions, has persuaded industry to enter into public-private partnerships to tackle neglected diseases such as malaria, HIV, and tuberculosis. Yet some infectious diseases—the world's “most neglected” diseases—are still being ignored not just by the pharmaceutical industry but also by public-private partnerships.

Why have these partnerships ignored the most neglected diseases, such as kala-azar, Chagas' disease, and sleeping sickness? This question was explored at a recent meeting in New York, organised by Médecins sans Frontières.¹ The answer lies in the social contract that exists between the public and private sectors.

The public sector has decided to make it public policy to leave drug development in the hands of the pharmaceutical industry. This industry in turn invests almost exclusively in developing drugs that are likely to be marketable and profitable—drugs for conditions such as pain, cancer, heart disease, and baldness. Public policies, such as tax incentives and patent protection, are geared towards this market driven private investment. As a result, out of 1393 new drugs marketed between 1975 and 1999, only 16 were for neglected diseases,² yet these diseases accounted for over 10% of the global disease burden. In contrast, over two thirds of new drugs were “me too drugs” (modified versions of existing drugs), which do little or nothing to change the disease burden.

The pharmaceutical industry only enters into public-private partnerships when it sees at least some potential market for its drug. For example, although people with malaria in the world's poorest countries cannot afford to pay for new malaria drugs, Western travellers can. Similarly, patients with tuberculosis or HIV in Africa or India cannot afford to purchase new treatments. However, many patients in the United States or Europe, whose health expenditure is covered partly by government run health insurance programmes, can pay for these treatments.

When the pharmaceutical industry sees enough of a market, the public sector then has sufficient leverage, or bargaining power, to persuade the private sector into a partnership. The bargaining power involves creating favourable conditions that make it attractive for industry to invest in drug development. For example, the public sector might reduce the costs of research and development through grants, tax credits, or public support for clinical trials, or it might create a purchase fund, in which donors ensure that there is a pot of gold ready to buy the new drug once it is developed. Examples of this type of approach are the Medicines for Malaria Venture, the International AIDS Vaccine Initiative, and the Global Alliance for TB Drugs Development.

When it comes to the world's most neglected diseases, however, these present absolutely no market opportunities. Without such opportunites, there is no incentive for the pharmaceutical industry to invest in drug research and development. The patients have no purchasing power, no vocal advocacy group is pleading for their needs, and no strategic interests—military or security—are driving concern about these conditions. This is why no public-private partnerships exist specifically for the most neglected diseases. The figure shows how these diseases fall totally outside the global pharmaceutical market.

For example, sleeping sickness, which claims thousands of lives annually in Africa, can be considered as a most neglected disease. Current drug treatments are in scarce supply, difficult to administer, and often toxic. Melarsoprol, which was developed over 50 years ago, kills up to 10% of people who are given the drug, and in some regions drug resistance means it is ineffective in a third of patients.³ An effective, less toxic drug, has been developed—eflornithine—but the company that developed it stopped its production in 1995, citing commercial failure. African patients could not afford to buy the drug. Eflornithine became available again five years later in the United States, when it was found to reduce unwanted facial hair in women.⁴ The injustice of American women depilating their faces while thousands in Africa were dying of a treatable illness finally led the original makers to restart production of the drug.⁵ It is currently available through a donation programme until 2006, though a long term producer is yet to be found.

Médecins sans Frontières believes that the best hope of treating the world's most neglected diseases is for the public to accept responsibility for drug development, taking it out of the marketplace and into the public sector. The organisation has launched an initiative on drugs for neglected diseases, founded only by public sector and non profit partners, such as the Pasteur Institute, the Special Programme for Research and Training in Tropical Diseases (a project undertaken jointly by the United Nations Development Plan, the World Bank, and the World Health Organization), the Indian Council for Medical Research, and the Brazilian government pharmaceutical organisation Fiocruz. The initiative is testing the idea that a drug research and development network can be established in the developing world, with a centralised management structure, and its feasibility study will be published later this year. Philippe Kourilsky, the director general of the Pasteur Institute, believes that the initiative will do “nothing short of creating a global, not-for-profit pharmaceutical industry.” If the initiative proves viable, it is likely to engage with the pharmaceutical industry on specific projects, since industry has great expertise in the development of drugs. The initiative, however, will not rely on market forces; it will define its needs, and then rely on public investment to meet them.

Will the strategy of taking medicines out of the marketplace work? Few precedents for truly international public initiatives exist (the Human Genome Project is an example), and the public investment will need to be massive. There will need to be concerted political attention to make available the necessary financial and technical resources. Right now there is little other hope for those dying of the world's most neglected, yet curable, infectious diseases.

Figure.

Three types of diseases