Public Health

Single injection of liposomal amphotericin cures visceral leishmaniasis

Last Updated: 2013-12-27 17:32:22 -0500 (Reuters Health)

By C. Vidya Shankar MD

NEW YORK (Reuters Health) - A single dose of intravenous liposomal amphotericin (AmBisome, Gilead) can cure visceral leishmaniasis, according to a new study from Bangladesh.

"The clinical implication of our study is huge," said lead author Dr. Dinesh Mondal in an email to Reuters Health.

Although known to be highly effective against leishmaniasis, the drug was too expensive and remained out-of-reach until a recent 90% price cut for resource-poor countries, the researchers point out.

Dr. Mondal, from the International Center for Diarrheal Diseases Research, Dhaka, Bangladesh, added in his email that not only is the treatment highly effective, but it's safe, it improves compliance, and it allows patients to be treated closer to home, with only a brief hospital stay.

Visceral leishmaniasis, also known as "Kala-azar" or black fever, is a potentially fatal parasitic infection caused by Leishmania donovani. It manifests with prolonged fever, anemia and splenomegaly.

Although it's been reported on every continent but Australia and Antarctica, 90% of cases are from the Indian subcontinent, the authors noted in a paper online December 5th in The Lancet Global Health. Each year, approximately 20,000 new cases are reported in Bangladesh and 100,000 in India.

The current treatment, oral miltefosine, fails in roughly a fifth of patients. Also, it's unsafe in pregnant women due to its teratogenic effects.

Liposomal amphotericin B is a lipid encapsulated formulation of anti-fungal amphotericin with a better safety profile than plain amphotericin.

In the disease endemic Mymensingh district in Bangladesh, Dr. Mondal's team enrolled 300 patients with visceral leishmaniasis confirmed by the rK39 antigen rapid test. There were 175 children and 125 adults, including 232 newly diagnosed patients and 28 relapsers.

Everyone received a single dose of IV liposomal amphotericin, 10 mg/kg. Treatment required only a day's stay in the hospital.

Initial cure was defined as resolution of fever, reduction in splenomegaly, and a 10% increase in hemoglobin concentration or a level of at least 100 g/L, at 30 days after treatment. A final cure was defined as a relapse-free period of at least 180 days.

Overall, 261 patients (87%) attained an initial cure and 290 (97%) achieved a final cure, in the intention-to-treat analysis.

The final cure rates were similar among children and adults and among primary cases and relapsers. The treatment was safe without significant side-effects, the authors say.

The most common cause of treatment failure in visceral leishmaniasis is poor compliance, said coauthor Prof. Shyam Sundar, from the Kala-azar Research Center in Varanasi, India, in email to Reuters Health. "Single dose AmBisome ensures 100% compliance being administered in one go, and thus minimizing the chances of resistance," he added.

The study supports the 2010 WHO recommendation on use of single-dose amphotericin as first-line in visceral leishmaniasis and "shows the feasibility of the drug's use under real-life conditions," Drs. P.K. Sinha and S. Bhattacharya write in an editorial.

This new regimen "could therefore support the elimination of visceral leishmaniasis as a major public health problem in southeast Asia," the researchers conclude.

SOURCE: http://bit.ly/1hKipIU

Lancet Global Health 2013.