An analysis of the safety of the single dose, two drug regimens used in programmes to eliminate lymphatic filariasis

This review of the safety of the co-administration regimens to be used in p rogrammes to eliminate lymphatic filariasis (albendazole + ivermectin or al bendazole + diethylcarbamazine [DEC]) is based on 17 studies conducted in S ri Lanka, India, Haiti, Ghana, Tanzania, Kenya, Ecuador, the Philippines, G abon, Papua New Guinea, and Bangladesh. The total data set comprises 90635 subject exposures and includes individuals of all ages and both genders. Re sults are presented for hospital-based studies, laboratory studies, active surveillance of microfilaria-positive and microfilaria-negative individuals , and passive monitoring in both community-based studies and mass treatment programmes of individuals treated with albendazole (n = 1538), ivermectin (9822), DEC (576), albendazole + ivermectin (7470), albendazole + DEC (6902 0), or placebo (1144). The most rigorous monitoring, which includes haemato logical and biochemical laboratory parameters pre- and post-treatment, prov ides no evidence that consistent changes are induced by any treatment; the majority of abnormalities appear to be sporadic, and the addition of albend azole to either ivermectin or DEC does not increase the frequency of abnorm alities. Both DEC and ivermectin show, as expected, an adverse event profil e compatible with thr destruction of microfilariac. The addition of albenda zole to either single-drug treatment regimen does not appear to increase th e frequency or intensity of events seen with these microfilaricidal drugs w hen used alone. Direct observations indicated that the level of adverse eve nts, both frequency and intensity, was correlated with the level of microfi laraemia. In non microfilaracmic individuals, who form 80 90% of the 'at ri sk' populations to be treated in most national public health programmes to eliminate lymphatic filariasis (LF), the event profile with the compounds a lone or in combination does not differ significantly from that of placebo. Data on the use of ivermectin + albendazole in areas either of double infec tion (onchocerciasis and I,T;), or of loiais (with or without concurrent LF ) are still inadequate and further studies are needed. Additional data are also recommended for populations infected with Brugia malayi, since most da ta thus far derive from populations infected with Wuchereria bancrofti.