Efficacy and Safety of Fexinidazole in Patients With Stage 1 or Early Stage 2 Human African Trypanosomiasis (HAT) Due to T.b. Gambiense: a Prospective, Multicentre, Open-label Cohort Study, plug-in to the Pivotal Study

The purpose of this study is to demonstrate the treatment success of fexinidazole, at one year follow-up visit, in HAT stage 1 and early stage 2 patients.

Primary Objective

-To demonstrate that the success rate of fexinidazole at one year follow-up in stage 1 and early stage 2 patients is greater than 80%. An 80 % success rate is considered as unacceptable.

Secondary Objectives

* To verify whether the success rate of fexinidazole treatment depends on the stage of the disease (stage 1 versus early stage 2); and, if the difference between the 2 stages is significant, to show that the success rate is greater than 80% and compatible with the historical success rate of NECT in early stage 2 patients and with the historical success rate of pentamidine in stage 1 patients.
* To verify whether the success rate of fexinidazole treatment depends on the number of WBCs in CSF before treatment initiation.
* To assess changes in the success rate over time.
* To evaluate the safety of fexinidazole and determine whether its safety profile is comparable to the historical safety profile of pentamidine.

Eligibility Criteria:
Inclusion Criteria:

* Signed informed consent
* 15 years old or more
* Male or female
* Ability to ingest at least one complete meal per day (or at least one Plumpy'Nut® sachet)
* Karnofsky index \> 50
* Presence of trypanosomes in blood or lymph
* Absence of trypanosomes in CSF
* Permanent address and ability to comply with the follow-up visit schedule
* Patient agreeing to be hospitalized to receive the treatment

Exclusion Criteria:

* Severely malnutrition, defined as BMI \< 16.
* Inability to take oral medication.
* Pregnancy or breastfeeding (a urine pregnancy test will be performed in all women of childbearing age within 24 h prior to treatment).
* Clinically relevant medical condition other than HAT that, in the Investigator's opinion, may jeopardize patient safety or interfere with participation in the study, including but not limited to significant liver or cardiovascular disease, documented or suspected active infection (including AIDS), CNS trauma or seizure disorders, coma or altered consciousness.
* Severely deteriorated general condition, e.g. cardiovascular shock, respiratory distress syndrome, or terminal illness.
* Any medical condition (except HAT specific symptoms) hindering communication with the Investigator as required for the completion of this study.
* Any contraindication to imidazole products (known hypersensitivity to imidazoles).
* History of HAT treatment in the past 2 years.
* Patients previously enrolled in the study or having already received fexinidazole.
* Expected follow-up difficulties (migrants, refugees, itinerant vendors, etc.).
* Current alcohol or drug abuse.
* Clinically significant abnormal laboratory value, such as:
* Alanine aminotransferase (ALAT) and/or aspartate aminotransferase (ASAT) \> 2 times ULN
* Total bilirubin (TBIL) \> 1.5 times ULN
* Severe leukopenia (\< 2000/mm3)
* Potassium (K+) \< 3.5 mmol/L
* Any clinically significant abnormal value (see details in Investigator Manual)
* Pregnancy confirmed by a positive urine pregnancy test obtained within 24 h prior to start of study treatment (see Section 5.8.3 Contraception; p35) QTcF ≥ 450 ms as measured automatically (if the first measurement is abnormal, a second assessment will be done at least 10-20 min later, with the patient in resting position)
* Patients not tested for malaria and/or not treated adequately for this infection
* Patients not treated adequately for soil-transmitted helminthic diseases