Response to Interferon-g plus Pentavalent Antimony in Indian Visceral

One hundred fifty-six previously untreated Indian patients with visceral leishmaniasis were treated with pentavalent antimony (Sb) alone for 30 days (group A), Sb plus interferon-g (IFN-g) for 30 days (group B), or Sb plus IFN-g for 15 days (group C). The purpose was to show that IFN-g would increase the response to 30 days of Sb treatment and that short-course (15 days) combination therapy was as effective as 30 days of Sb alone. Six months after treatment, 36 % of group A, 49% of group B, and 42 % of group C patients were designated as definitively cured. The success rates for long-term responses to Sb alone (36%) and Sb plus IFN-g (49%) were unexpectedly low, and responses in groups A, B, and C were not significantly different. These results suggest that the beneficial effects of adjunctive IFN-g in visceral leishmaniasis may be limited in regions where this disseminated intracellular infection shows high-level resistance to Sb. In an earlier trial using previously untreated Indian patients To remedy this shortcoming, we conducted a second larger trial in which patients were randomized for 30 days of treatmentwith visceral leishmaniasis (kala-azar) [1], we demonstrated that the addition of interferon-g (IFN-g) as cytokine immuno- with Sb alone or Sb plus IFN-g. A third group of patients was randomized to receive Sb plus IFN-g for 15 days to determinetherapy accelerated the parasitologic effect and enhanced the clinical efficacy of conventional pentavalent antimony (Sb) if the duration of Sb treatment in kala-azar can be effectively treatment. In view of the declining effectiveness of Sb in Indian shortened by using IFN-g. kala-azar [2–4] and the recommendation to extend already prolonged initial treatment (28–30 days) to ⁄40 days [5], Methodsboth of the added effects produced by IFN-g made it appear potentially useful. IFN-g is well recognized as an activatin