Triple-Drug Therapy Superior to Two Drugs for Treating Lymphatic Filariasis

Prof.Dr.Dram,profdrram@gmail.com,Gastro Intestinal,Liver Hiv,Hepatitis and sex diseases expert 7838059592,9434143550

The World Health Organization (WHO) has targeted lymphatic filariasis for elimination by 2020. Despite progress achieved using mass drug administration (MDA), an estimated 852 million people in 52 countries still require preventive chemotherapy. Can outcomes from MDA programs be improved?

Researchers randomized 182 adults (1:1:1) in Papua New Guinea with Wuchereria bancrofti microfilaremia to receive a single dose of a three-drug regimen, a single dose of a two-drug regimen, or a two-drug regimen yearly for 3 years. The two-drug regimen included diethylcarbamazine (6 mg/kg) and albendazole (400 mg). The three-drug regimen added ivermectin (200 μg/kg). All drugs were given orally under direct observation.

After the three-drug regimen, 96% of participants were clear of microfilaremia at 12 months; the same rate of clearance was found at 24 and 36 months. Clearance was significantly better than with the single dose, two-drug regimen (32%, 56%, and 83% clearance at 12, 24, and 36 months). Clearance at 36 months with triple-drug therapy was not inferior to clearance with two-drug therapy once yearly for 3 years (98% at 36 months). No serious adverse events were noted; moderate adverse events were more common for three-drug than two-drug recipients (27% vs. 5%). Participants with higher baseline microfilarial counts had more-severe and more frequent adverse events.

Rapidity of microfilarial clearance is relevant because blood microfilariae are a source of onward transmission via mosquitoes. Although three doses of the two-drug regimen was not inferior at 3 years, repeat dosing is a barrier to successful implementation. The advantage of the three-drug regimen is that a single encounter can clear microfilariae for most. The WHO has now recommended the triple-drug regimen for selected regions. As an editorialist observes, triple-drug treatment is not recommended for parts of Africa because of potential adverse effects in areas where loiasis or onchocerciasis is co-endemic, but potential added benefits from including ivermectin, where possible, are reduced transmission of scabies and intestinal helminths.