Background: Miltefosine is the first oral drug with demonstrable success in treating visceral leishmaniasis in adults. Because approximately one-half of the visceral leishmaniasis patients worldwide are children, we performed a Phase I/II dose ranging study in the pediatric population in India.
Methods: Thirty-nine (39) children (defined as < 12 years of age) with visceral leishmaniasis demonstrated by parasites in splenic aspirates, were treated with oral miltefosine daily for 28 days: 21 patients received 1.5 mg/kg/day (Group A); and 18 patients received 2.5 mg/kg/day (Group B). About one-half of these children had failed prior antileishmanial treatment.
Results: All patients were parasitologically negative and symptomatically improved by the end of therapy on Day 28 of therapy; the initial parasitologic cure rate was 100%. Two patients in each treatment group relapsed with fever, splenomegaly and parasite-positive splenic aspirates by the end of the 6-month follow-up. The per protocol final clinical cure rate was 19 of 21 = 90% in Group A and 15 of 17 = 88% in Group B. Miltefosine was well-tolerated. As per the adult experience, gastrointestinal adverse events were seen: 33 and 39% of children experienced vomiting and 5 and 17% experienced diarrhea in Groups A and B, respectively, but all episodes were mild to moderate in severity and commonly lasted <1 day without symptomatic treatment.
Conclusion: Oral miltefosine was safe and approximately 90% effective in this initial clinical trial of childhood visceral leishmaniasis.