The European Medicines Agency’s (EMA’s) Committee for Medicinal Products for Human Use has adopted a positive opinion for Acoziborole Winthrop (acoziborole, Sanofi Winthrop Industrie) for the treatment of human African trypanosomiasis (HAT) due to Trypanosoma brucei gambiense (g-HAT).

Current therapies for g-HAT involve multiple doses, intravenous infusions, or intramuscular injections, as well as hospitalisation. 

Acoziborole Winthrop is given as a single oral dose and is effective in all stages of g-HAT, removing the need for lumbar puncture and hospitalisation. This simplifies treatment for patients, facilitating compliance and accessibility.

The positive opinion was adopted for use of the drug outside the European Union, which was assessed under the EU-M4all program. This aims to facilitate patient access in low- and middle-income countries to essential medicines intended to prevent or treat diseases of major public health interest. The application for scientific opinion was assessed under an accelerated timetable to enable faster patient access to the medicine.

HAT is spread through the bite of tsetse flies infected with the parasite T brucei gambiense. It is endemic in sub-Saharan Africa. Initially patients may experience fever, headache, and rash (first stage). Later, they may experience a more severe form of the disease that affects the nervous system, causing symptoms such as sleep disturbances and changes in behaviour (second stage). Without treatment, HAT is generally fatal.

The active substance of Acoziborole Winthrop is the antiprotozoal acoziborole. The EMA said that available data suggested that acoziborole binds to cleavage and polyadenylation specificity factor 3 in T brucei gambiense, inhibiting the maturation of its mRNA. The boron atom in the drug’s molecular structure is thought to be essential for the trypanocidal activity, though the precise molecular interactions have not been fully characterised.

Acoziborole Winthrop is indicated for the treatment of both first-stage (hemo-lymphatic) and second-stage (meningo-encephalitic) disease, including severe second-stage with ≥ 100 white blood cell count/μL with or without trypanosomes in the cerebrospinal fluid, HAT due to T brucei gambiense in adolescents ≥ 12 years old with body weight ≥ 40 kg, and in adults. 

The single-dose oral treatment will be available as 320 mg tablets.

The safety and efficacy of acoziborole are based on the results of a single-arm open-label phase 2/3 clinical trial carried out in the Democratic Republic of Congo and Guinea. The study involved 208 adults and adolescents from 15 years of age with g-HAT who received a single dose of the medicine.

The results showed that, after 18 months, treatment was successful in 95.2% of people with second-stage disease and in 100% of people with first- and intermediate‑stage g-HAT.

The most common side effects of the treatment are pyrexia, asthenia, decreased appetite, tremor, and headache.

Rob Hicks is a retired National Health Service doctor. A well-known TV and radio broadcaster, he has written several books and has regularly contributed to national newspapers, magazines, and online publications. He is based in the United Kingdom.