Fexinidazole for Chagas
Evaluate efficacy and safety of short-course and low-dose regimens of fexinidazole in adults with chronic Chagas disease
last phase of drug development




updated 25 Feb 2025
A Phase II Proof of Concept (PoC) study of fexinidazole was initiated in 2014 in Cochabamba and Tarija, Bolivia. The study was interrupted due to safety and tolerability issues. Interim data efficacy and safety analysis suggested potential high efficacy rates of fexinidazole and a decision was made to extend clinical study follow-up to 12 months. Analysis of key efficacy outcomes and safety confirmed the potential high efficacy findings at the lowest dose tested and for all treatment durations, with safety concerns around treatment with high doses tested for more than 14 days. In addition, acceptable safety and tolerability was found at low doses and short treatment durations – taken together, these results warrant further investigation of fexinidazole for Chagas disease.
Although the Fexinidazole for Chagas project showed promising potential, with positive safety results for shorter regimens, the study did not demonstrate the expected efficacy compared to the standard of care. Given this, DNDi has decided not to pursue its further development.
Project updates
2022
The clinical study report on the Phase II trial was completed at the end of 2022. The results of the study are expected to be published in early 2023.
2021
A Phase II proof-of-concept study using shorter and lower-dose treatment regimens that began in October 2017 at four sites in Spain was completed, with final analyses concluded in early 2022. Results showed that the efficacy of fexinidazole at lower doses and durations was not confirmed after 12 months. Future development of fexinidazole is under review to assess potential use in combination with other drugs or for new indications, such as for immunocompromised patients at risk of reactivation.
2019
DNDi is evaluating fexinidazole, which was registered to treat sleeping sickness in 2018, as a potential new drug for Chagas disease. This Phase II proof-of-concept study, carried out in five sites in Spain, has been evaluating different short-course regimens of fexinidazole for adults with chronic indeterminate Chagas. The follow-up phase of the study was completed in late 2019; results will be available in 2021.
2018
By September 2018, 45 patients had been recruited for this Phase II proof-of-concept study carried out in five sites in Spain to test different short-course regimens of fexinidazole for adults with chronic indeterminate Chagas. The study is now in the follow-up phase and will be completed in late 2019 with results available in 2020.
2017
A new Phase II proof-of-concept study using shorter and lower-dose treatment regimens started in October 2017 at four sites in Spain (three in Barcelona, one in Valencia) with a fifth site to be opened in Madrid. The target conclusion date is mid-2019. This is the first time DNDi conducts a clinical trial for Chagas disease outside Bolivia and Latin America.
2016
A new PoC study has been designed and will be run in four sites in Spain. Recruitment of patients is planned for 2017.
News & resources
- 10 January 2024 – Efficacy and safety of fexinidazole for treatment of chronic indeterminate Chagas disease (FEXI-12): a multicentre, randomised, double-blind, phase 2 trial, The Lancet Infectious Diseases
- 10 January 2024 – Clinical trial confirms the tolerability of the drug fexinidazole in the treatment of Chagas disease
- 4 August 2022 – A phase-2, randomized, multicenter, placebo-controlled, proof-of-concept trial of oral fexinidazole in adults with chronic indeterminate Chagas disease, Clinical Infectious Diseases
- 27 March 2019 – A pharmacokinetic-pharmacodynamic assessment of the hepatic and bone-marrow toxicities of the new trypanoside fexinidazole, Antimicrobial Agents and Chemotherapy
- 12 August 2014 – New Drug Candidate for Chagas Disease Tested in Patients in Bolivia
Clinical trials documents
- Centre National de Pharmacovigilance (CNPV), Université de Kinshasa, DRC
- Collective of Applied Studies and Social Development (CEADES), Bolivia
- Fundacio Investigacio Hospital General Valencia, Spain
- Hospital Clínic de Barcelona, Spain
- Hospital General de l’Hospitalet and Hospital de Sant Joan Despí Moisès Broggi, Consorci Sanitari Integral, Spain
- ISGlobal, Barcelona Institute for Global Health, Spain
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Argentina
- Luxembourg Institute of Health, Luxembourg
- Platform of Integral Care for Patients with Chagas Disease, Tarija and Cochabamba, Bolivia
- Unidad de Enfermedades Infecciosas, Seccion de Salud Internacional y Consejo al Viajero, Spain, Spain
- Universidad Autónoma Juan Misael Saracho, Bolivia
- Universidad Mayor de San Simon, Bolivia
- University Hospital Bonn, Germany
- Vall d’Hebron University Hospital, Spain
- Centre National de Pharmacovigilance (CNPV), Université de Kinshasa
- ,DRC
- Collective of Applied Studies and Social Development (CEADES)
- ,Bolivia
- Fundacio Investigacio Hospital General Valencia
- ,Spain
- Hospital Clínic de Barcelona
- ,Spain
- Hospital General de l’Hospitalet and Hospital de Sant Joan Despí Moisès Broggi, Consorci Sanitari Integral
- ,Spain
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET)
- ,Argentina
- ISGlobal, Barcelona Institute for Global Health
- ,Spain
- Luxembourg Institute of Health
- ,Luxembourg
- Platform of Integral Care for Patients with Chagas Disease, Tarija and Cochabamba
- ,Bolivia
- Unidad de Enfermedades Infecciosas, Seccion de Salud Internacional y Consejo al Viajero, Spain
- ,Spain
- Universidad Autónoma Juan Misael Saracho
- ,Bolivia
- Universidad Mayor de San Simon
- ,Bolivia
- University Hospital Bonn
- ,Germany
- Vall d’Hebron University Hospital
- ,Spain
- Collective of Applied Studies and Social Development (CEADES), Bolivia
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Argentina
- Fundacio Investigacio Hospital General Valencia, Spain
- Hospital Clínic de Barcelona, Spain
- Hospital General de l’Hospitalet and Hospital de Sant Joan Despí Moisès Broggi, Consorci Sanitari Integral, Spain
- Luxembourg Institute of Health, Luxembourg
- Platform of Integral Care for Patients with Chagas Disease, Tarija and Cochabamba, Bolivia
- Unidad de Enfermedades Infecciosas, Seccion de Salud Internacional y Consejo al Viajero, Spain, Spain
- Universidad Autónoma Juan Misael Saracho, Bolivia
- Universidad Mayor de San Simon, Bolivia
- Vall d’Hebron University Hospital, Spain
- ISGlobal, Barcelona Institute for Global Health, Spain
- University Hospital Bonn, Germany
- Centre National de Pharmacovigilance (CNPV), Université de Kinshasa, DRC
- Germany - Federal Ministry of Education and Research (BMBF) through KfW
- Switzerland - Swiss Agency for Development and Cooperation (SDC)
- The Netherlands - Dutch Ministry of Foreign Affairs (DGIS)
- UK - UK International Development
- Bem-Te-Vi Diversidade
- Mundo Sano (PRV)
- Médecins Sans Frontières International
- Other private foundations and individuals
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