A single treatment for visceral leishmaniasis under study
Faster with fewer side effects
A new TDR study in collaboration with McGill University will begin in January to determine if a single dose of liposomal amphotericin B is feasible to treat visceral leishmaniasis in Indian primary health care centres. If successful, the single intravenous drip that takes about 2 hours will be an important improvement over the current standard of miltefosine pills over a 28 day course. Many people do not finish this treatment because it requires such a long time period and there are toxic side effects.
The study is part of a multidisciplinary and multi-centre project coordinated by the Drugs for Neglected Diseases initiative (DNDi), which was awarded a US$ 9 million grant from the Bill & Melinda Gates Foundation over 3 years. TDR and One World Health (OWH) are the other partners in the effort toward eliminating this deadly disease. (More information on the full project is in the link to the right.)
Visceral leishmaniasis (VL) is highly endemic in the Indian subcontinent and in East Africa. Also known as kala-azar (black illness), it is a infectious disease caused by the Leishmania donovani (L. donovani) parasite that is transmitted by the bite of an infected sandfly. The main clinical features are prolonged fever, anaemia, an enlarged spleen and liver, prominent wasting and, when untreated, death due to internal bleeding or opportunistic infections. There are an estimated 360 000 new cases of VL worldwide each year and over 60% of these occur in the northern state of Bihar, India and the bordering regions of Nepal and Bangladesh.
An earlier study of treatment with the single dose of liposomal amphotericin B (manufactured as AmBisome®) showed a 96% cure rate in a hospital setting with fewer side effects than other treatments. However, the majority of patients do not have easy access to hospitals, so this next study is designed to determine whether diagnosis and treatment can be managed in the government primary health centres. Health care providers are being trained to use a rapid diagnostic test from a drop of blood, and if found positive, to treat on the same day with the single dose of AmBisome®. TDR is conducting this study in India as part of the DNDi study, and also in Bangladesh and Nepal in other studies. If the study is successful, treatment could be provided within several kilometers of the villages where the largest burden of visceral leishmaniasis exists.
The preferential pricing agreement for developing countries secured by WHO in 2007 for the purchase of AmBisome® at 10% of its original price brings the cost for this treatment in line with previous treatments. Families of visceral leishmanisis patients save even further because only a single visit to a primary health care centre would be needed.
TDR and McGill are working with the Indian government during this time so that once the feasibility studies are completed and if the results are positive, the system can be quickly adopted. This study is part of a two-pronged approach – the treatment is being paired with active case detection, another research project of TDR and McGill and Banaras Universities.