OBJECTIVE 1: Optimization of MDA with existing drugs for lymphatic filariasis and onchoceriaisis
Part 1: Cost/benefit based studies of accelerated mass drug administration (MDA) for elimination of lymphatic filariasis (LF)
Part 2: Population based studies of accelerated mass drug administration (MDA) for elimination of lymphatic filariasis (LF)
Seven of these large, community-based studies are ongoing in 6 countries in Africa, Asia, and in the western Pacific. Five studies are comparing the relative impact and cost effectiveness of annual vs. semiannual MDA for elimination of LF. We are also performing two community studies to determine whether MDA with Albendazole alone can eliminate LF in Central Africa where the standard MDA regimen (Ivermectin plus Albendazole) cannot be used because of coendemic loiasis. Results from these studies have the potential to significantly accelerate progress toward global elimination of LF.
OBJECTIVE 2: Clinical trials to test the impact of new drug combinations and treatment schedules for lymphatic filariasis and onchocerciasis using currently used drugs
We are conducting four randomized clinical trials to identify safe and effective treatments utilizing combinations of existing drugs that are more effective than those currently used for MDA. Two studies are testing whether Ivermectin/Albendazole regimens are superior to Ivermectin alone for killing or sterilizing adult Onchocerca volvulus worms. One study is comparing different Albendazole regimens to the standard MDA regimen used in Africa (annual Albendazole/Ivermectin). The fourth study is comparing the efficacy of a triple drug regimen (Iver/Alb/DEC) to DEC plus Albendazole (the standard MDA regimen for LF outside of Africa).
OBJECTIVE 3: Effect of MDA for LF on soil-transmitted helminth infections
DOLF is collecting important data on impact of community-wide MDA for LF on STH infections in various countries. First surveys show varying results, mostly affected by the kind of treatment (albendazole alone, ivermectin combined with albendazole or DEC combined with albendazole), the frequency of treatment, pre-treatment prevalence and density of STH, the ecological background of the study area, and the composition of STH species. For example it appears that low level of hookworm infection can be efficiently controlled or even eliminated by community-wide twice yearly MDA with albendazole in the a remote study area in the Republic of Congo but high levels of Ascaris and hookworm infections are difficult to suppress permanently with twice yearly DEC combined with albendazole on Flores island in Indonesia.
OBJECTIVE 4: Community studies of ivermectin+DEC+albendazole (IDA) vs. DEC+albendazole (DA) for lymphatic filariasis
Based on the results from the clinical trials we are assessing the potential of IDA for LF elimination on the community level. These studies are evaluating the safety, acceptability, and efficacy of IDA for lymphatic filariasis in 5 countries (Fiji, Haiti, India, Indonesia and Papua New Guinea) outside Africa with varied LF epidemiology and MDA histories. Our goal is perform cohort event monitoring for at least 10,000 individuals treated with IDA and compare the outcome with the standard MDA treatment regimen. These data are needed for the guideline review process at WHO and for consideration by drug donors and other stakeholders in the LF elimination program.