July 16, 2021
The U.S. FDA has approved Sanofi’s fexinidazole tablets to treat both stages of sleeping sickness (human African trypanosomiasis, or HAT) caused by Trypanosoma brucei gambiense in patients who are at least six years old and weigh at least 20kg (44 pounds). Sanofi developed fexinidazole in partnership with the Drugs for Neglected Diseases initiative (DNDi), a nonprofit research and development organization, which conducted clinical trials in partnership with Sanofi and the National Sleeping Sickness Programs of the Democratic Republic of Congo (DRC) and Central African Republic (CAR).
- b. gambiense is a protozoan (single-celled animal) parasite transmitted to humans through the bite of the tsetse fly, an insect found only in Africa. It causes a slowly progressing form of HAT that has two stages, defined by whether or not the parasite has crossed the blood-brain barrier. In the second stage, when the parasite has crossed the barrier, the disease affects the central nervous system. Several effective treatments are available, but fexinidazole offers the only oral option for treating both stages of HAT.
In three clinical trials, fexinidazole delivered cure rates ranging from 91.2% to 98.7% after 10 days of treatment. It was found to be most effective in patients who were in the first stage of HAT. For patients who have severe second stage disease, the prescribing information recommends using fexinidazole tablets only if there are no other available treatment options, due to its decreased efficacy.
Recommended dosing is based on the patient’s weight and consists of a loading dose taken for four days, followed by a maintenance dose taken for six days. Fexinidazole must be administered with food, and patients should avoid consuming alcohol throughout treatment and for at least 48 hours after completing their fexinidazole regimen.