Girl with post Kala Azar Dermal Leishmaniasis, a recurrent but non-fatal form of Kala Azar that affects 5-10 per cent of patients between six months to three years after cure. Photograph by Matthew Smeal
Letter |

Global Health Groups Appeal to Congress: Fix the FDA PRV for Neglected Diseases

Fix FDA PRV for NTDs letter cover
Photograph by Matthew Smeal

April 28, 2017

Honorable Members of U.S. Congress: 

We are writing to request that you amend the Food and Drug Administration (FDA) Priority Review Voucher (PRV) program for neglected diseases. Amendments could help ensure that the program effectively accomplishes its goal of incentivizing new research and development (R&D) for neglected diseases, and that new neglected disease products brought to market through the PRV program are made accessible and affordable to those who need them.

As several of the most recent and ongoing global health emergencies have reminded the world, the need for well-functioning incentives for R&D for neglected diseases is today more urgent than ever. Yet, despite representing more than 10% of the global disease burden, only 4% of new drugs and vaccines approved across the world were indicated for neglected diseases between 2000 and 2011.1

In May 2016, the American Thoracic Society, Doctors Without Borders/Médecins Sans Frontières, the Drugs for Neglected Diseases initiative, HIV Medicine Association, Infectious Diseases Society of America, the Sabin Vaccine Institute, the TB Alliance and the Treatment Action Group sent a letter to U.S. Congress expressing our concerns with the design of the FDA PRV program for neglected diseases and asking for changes to fix the program.2

The monetary value of PRVs has been established through sales, with vouchers being sold for up to $350 million.3 However, the value of these vouchers as an incentive to promote innovation for new therapeutic and preventive options for populations affected by neglected diseases depends on the PRVs being awarded only to treatments and vaccines that are new for people affected by neglected diseases and that are accessible to those who need them.

Nevertheless, the absence of requirements for a product to be new or to be made available and affordable for those for whom the product is designed are two critical flaws in the design of the neglected disease PRV program that remain unaddressed. To address these flaws, this Congressionally-mandated program must be amended by Congress. As the PRV program for neglected diseases reaches a ten-year anniversary this year, we urge Congress to fix the neglected disease FDA PRV program to ensure that new neglected disease medical products, including treatments and vaccines, are appropriately incentivized and are accessible to the patients and health care providers who urgently need them.

There are two key amendments to the PRV program for neglected diseases that we strongly recommend:

1. The PRV program should have a novelty requirement. Under current law, a PRV for neglected diseases can be awarded even when the medical product already exists and is not new to people affected by neglected diseases. 

The PRV rewards successful FDA registration of products for select neglected diseases that have not been registered in the U.S., even if that drug or vaccine has already been in use to treat or prevent the neglected disease in other countries for years. Two of the FDA PRVs for neglected diseases, awarded to Knight Therapeutics and Novartis for products for treatment of leishmaniasis (miltefosine)4 and malaria (artemether-lumefantrine) respectively, were for drugs already in use for a long time in other countries. One was for a cholera vaccine for which the effectiveness had not been established in persons living in cholera-affected areas. 5 A PRV should only be awarded to products that are truly new to people affected by neglected diseases, or that are registered with the FDA in a timely manner after initial registration in disease-endemic countries.

2. The PRV program should require an access strategy. The PRV program for neglected diseases does not include any mechanism to ensure patients, governments and health care providers will have affordable and appropriate access to products for which a PRV has been awarded.

Critically, the PRV program for neglected diseases does not ensure that the qualifying products will be accessible and affordable to patients in need.6 PRV recipients are not even required to market a product that earns a PRV. Additionally, products that are marketed do not need to be priced affordably. For example, in the case of miltefosine, health care providers like MSF, R&D organizations like DNDi, governments and others are still struggling to access this product at an affordable price – or in some cases to access it at all. A PRV should only be awarded to companies who commit to serious efforts to make the PRV-earning neglected disease product available and accessible to patients in disease-endemic countries, whom the PRV program is intended to benefit.

Straightforward statutory changes, based on existing law for the rare pediatric disease PRV program and proposed legislation for PRV programs, could help to remedy the functioning of the PRV for neglected diseases.

As organizations working to develop and provide access to neglected disease treatments and vaccines, we see every day the need for more effective strategies to incentivize needs-driven R&D for neglected diseases, including appropriate rewards for investments.7 Improvements to the PRV program will be one important step toward broader changes that are urgently needed to ensure the R&D system delivers appropriate and affordable health technologies for those who need them. We, therefore, hope that this Congress will not only amend the PRV program for neglected diseases, but also consider the potential creation of additional mechanisms to ensure that R&D for global public health needs is successfully and appropriately incentivized and that all patients in need can benefit from the fruits of biomedical innovation.


American Thoracic Society

Drugs for Neglected Diseases initiative

HIV Medicine Association

Infectious Diseases Society of America

Médecins Sans Frontières/Doctors Without Borders USA

TB Alliance

Treatment Action Group


1 Pedrique B, et al. The drug and vaccine landscape for neglected diseases (2000-11): a systematic assessment. Lancet 2013, 1(6):
2 Letter sent to US Congress May 19, 2016, available
3 See:
4 Doshi P. US incentive scheme for neglected diseases: a good idea gone wrong? BMJ 2014; 349:g4665
5 See:
6 See, for
example:, and
7 2008 WHO Global Strategy and Plan of Action on Public Health, Innovation and Intellectual Property (WHA61.21) and 2012 Report of the WHO Consultative Expert Working Group on Research and Development: Financing and Coordination (CEWG report), see:

Global health groups appeal to congress: Fix the FDA PRV for neglected diseases