A vaccine against one of the most neglected yet fatal tropical diseases is being tested for the first time in a clinical trial in India and the US. After malaria, leishmaniasis is the second largest parasitic killer, and the visceral form is the most deadly.
“Visceral leishmaniasis (VL) kills 50,000 persons per year, 70 percent of them children. It can be treated but the costs are too high… at hundreds of US dollars per person,” said Dr Franco Piazza at the Infectious Disease Research Institute (IDRI), a Seattle-based NGO that developed the vaccine with funding from the Bill and Melinda Gates Foundation.
The leishmaniasis group of diseases is transmitted by infected sand flies, which carry a parasite that attacks the liver, spleen and bone marrow. Left untreated, VL is almost always fatal, said Philippe Desjeux, a specialist in the infection at the San Francisco-based non-profit OneWorld Health.
The clinical trial testing IDRI’s vaccine is led by Gennova Pharmaceuticals - a Pune-based Indian company to which IDRI has transferred its technology - in collaboration with the Banaras Hindu University in Varanasi.
“We have just opened a formulation centre [research and production facility] for vaccines against neglected diseases in Pune," said Sanjay Singh, the chief executive officer of Gennova. “If the vaccine passes all the tests, producing it in India will make it affordable to all the people who are affected by VL.”
The infection is one of more than a dozen grouped as “neglected tropical diseases”, occurring mostly in tropical countries where they kill an estimated half million people annually and for which few treatments exist due to lack of funding for research and treatment.
A total of 72 volunteers are participating in the trial, but scientists say it will take years of testing to roll out an affordable vaccine to the 200 million people globally at risk of VL infection.
VL is most fatal in South Sudan, where poverty and conflict make even relatively inexpensive methods like treated bed nets to protect people from infected sand flies hard to implement.
The WHO has warned that VL is spreading to previously unaffected countries due to co-infections of HIV and leishmaniasis, while the Intergovernmental Panel on Climate Change (IPCC) has said climate change can also spur the spread of the disease.
*This article was amended on 11 May 2012. The original report erroneously reported that OneWorld Health was part of the vaccine trials