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Expanded Drug Commitment Could Accelerate Elimination of Lymphatic Filariasis


In response to new treatment guidelines from the World Health Organization (WHO), Merck & Co., Inc. (known as MSD outside the United States and Canada) has announced that it will expand the Mectizan® Donation Program (MDP) to reach up to an additional 100 million people per year through 2025 as part of the global effort to eliminate lymphatic filariasis (LF).

LF is a disabling and disfiguring neglected tropical disease that affects an estimated 120 million people worldwide. Merck & Co., Inc. donates the anti-parasitic drug ivermectin to MDP for the elimination of both LF and river blindness. With the new commitment, the company will now donate up to 480 million treatments annually to MDP, which is a program of The Task Force for Global Health.

WHO revised its treatment guidelines after research showed that a three-drug combination that includes ivermectin is more effective than a two-drug treatment regimen in eliminating LF in endemic countries where there is no river blindness.

“The triple-drug therapy is more effective and just as safe,” said MDP Director Yao Sodahlon, MD.

Triple drug therapy could potentially accelerate LF elimination in countries where the disease is endemic. The Task Force’s Neglected Tropical Diseases Support Center (NTD-SC) helped with the research on the safety and social acceptability of the therapy that led to the revised WHO guidelines, including conducting clinical trials in India and Fiji.

NTD-SC staff recently visited Kenya – which could be the first country to administer the three-drug therapy on a large scale – to establish a protocol for eliminating LF the country. This will include providing recommendations for mass drug treatment with the new triple-drug therapy that also includes the drugs diethylcarbamazine and albendazole, and determining the metrics for success.

Kenya’s Neglected Tropical Diseases program head Sultani Matendechero said the increased donation of ivermectin will reduce the time needed to eliminate LF in his country from five to two years. “That is an exciting prospect,” he said.

Commonly known as elephantiasis, LF is caused by parasitic worms that are spread by mosquitoes. The infection damages the lymphatic system and causes massive swelling of lymph glands in the legs and lower body, resulting in long-term disability and social stigma.

Efforts to eliminate the disease have focused on treating entire communities where the disease is endemic. This strategy of mass drug administration eliminates the disease by curing existing infections and preventing new ones. “The accelerated elimination will protect millions of people from the risk of developing this life-changing condition,” Matendechero said.

Of the 73 countries where LF is endemic, 40 are on track to achieving elimination by 2025, according to WHO. In 2017, Togo became the first African country to eliminate LF with support from partners including MDP.

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