Drug development for neglected tropical diseases: DNDi and the product development partnership (PDP) model.

Abstract Neglected tropical diseases (NTDs), including leishmaniasis, Chagas disease, sleeping sickness, dengue fever, and schistosomiasis to name a few, are endemic in 149 countries and impact 1.4 billion people- often the most vulnerable groups in the poorest countries (WHO 2016). Unfortunately, many of these diseases have no vaccines to prevent them, nonexistent or incredibly problematic treatments, and limited resources dedicated to monitoring, controlling, and improving the situation of those who are infected. These diseases may impact millions of people, but the affected population is too poor to exert economic sway and attract investment under the current medical research and development system, and a long-standing market failure has left their needs unmet. However, since the turn of the century, the growing humanitarian concern for NTDs has prompted exploration into innovative partnership and financing mechanisms for developing health technologies for these diseases. Product development partnerships (PDPs), such as the Drugs for Neglected Disease Initiative (DNDi), have emerged to coordinate new collaborations between private industry, academia, and the public sector. Furthermore, the political landscape around NTDs is changing as exemplified by the fact that the World Health Organization (WHO) is endorsing demonstration projects to experiment with "delinkage" principles that aim to separate the innovation market from the price of products and increase affordability and access. These novel approaches to drug development are important case studies in understanding how to best address the market failure around diseases of poverty and offer insight as to what strategies effectively advance the development of innovative health technologies. The lessons learned from the activities of DNDi and other PDPs shed light on how to align the goals of global health with political and economic realities.