Clinical Trials Logo

Clinical Trial Summary

The disease leishmaniasis mainly occurs in hot and tropical countries, affects millions of people and causes around 20,000 deaths across the world every year. Leishmaniasis is caused by the Leishmania parasite and is transmitted by sand flies. The parasite is tiny and not visible to the naked eye, whereas the sand fly is visible but small and inconspicuous. There are different types of leishmaniasis which can affect the skin (cutaneous leishmaniasis) or the internal organs of the body (visceral leishmaniasis). Some of the milder forms will produce skin problems which will be localised, whilst other forms of leishmaniasis will cause widespread skin changes. The skin lesions of cutaneous leishmaniasis can be disfiguring if left untreated. There are some treatments for leishmaniasis but many of them are not easy to use or don't work well. Therefore, new treatments are needed including vaccines that prevent or work against leishmaniasis. A solution being adopted for other diseases, which the investigators now wish to adopt for leishmaniasis is to develop a 'Controlled human infection model' (CHIM). These models involve deliberate exposure of individuals to an infection, in order to better understand how the disease works and to test potential vaccines and treatments. They have contributed knowledge that has led to advances in the development of treatments. This is study builds on an our initial successful study, FLYBITE, where uninfected (disease-free) sand flies were used to test the safety aspects and ensure that sand flies were able to bite human participants in a controlled environment. The investigators observed no major adverse effects and it was well tolerated by participants. The investigators therefore wish to proceed to a study using sand flies infected with a form of leishmaniasis that causes localised skin disease and is treatable, on the pathway to assessing future vaccines.


Clinical Trial Description

This is a clinical study in up to twelve healthy Leishmania-naïve subjects aged between 18 and 50 years old who develop a confirmed sand fly bite. Initially six subjects will be studied and exposed to biting by Phlebotomus duboscqi infected by Leishmania major. An adaptive design will be used, that has been pragmatically designed to minimise unnecessary exposure of volunteers to Leishmania and maximise the likelihood of developing a reproducible Controlled Human Infection Model. The primary objective is the development of a controlled human infection model of Leishmania major using sand fly transmission which is (a) effective and (b) safe. The first six subjects will be exposed to biting by Phlebotomus duboscqi (sand fly species) infected by Leishmania major (species of leishmaniasis causing cutaneous, ie skin disease) and assess the 'take rate', that is the number of subjects developing parasitologically confirmed cutaneous leishmaniasis (PCCL) lesions. If 6/6 subjects develop PCCL lesions no further recruitment will take place; if only < 6 subjects develop PCCL lesions, then an adaptive design will be followed. This study is based on an initial study, entitled FLYBITE (clinicaltrials.gov identifier: NCT03999970). the FLYBITE study was a clinical study to develop a sand fly biting protocol using pathogen-free blood-fed sand flies. Twelve healthy participants were enrolled into the study and all 12 participants experienced at least one successful sand fly bite. ;


Study Design


Related Conditions & MeSH terms


NCT number NCT04512742
Study type Interventional
Source University of York
Contact
Status Completed
Phase N/A
Start date October 16, 2021
Completion date November 1, 2023

See also
  Status Clinical Trial Phase
Completed NCT03641339 - Defining Skin Immunity of a Bite of Key Insect Vectors in Humans N/A
Completed NCT04504435 - Safety, Tolerability and Pharmacokinetics (PK) Investigation of GSK3494245 in Healthy Participants Phase 1
Completed NCT00004755 - Allopurinol, Glucantime, or Allopurinol/Glucantime for Cutaneous Leishmaniasis in Brazil Phase 2
Completed NCT00657618 - Use of Sodium Stibogluconate as a Treatment for Leishmaniasis Phase 1/Phase 2
Recruiting NCT00344188 - Diagnosis and Treatment of Leishmania Infections
Active, not recruiting NCT03009422 - Fractional CO2 Laser With Topical Pentostam Treatment for Cutaneous Leishmaniasis. N/A
Recruiting NCT05449717 - Incidence of Relapse and Post-Kala-Azar Dermal Leishmaniasis in South Sudan
Recruiting NCT06307171 - Human Leishmaniasis: Antigen Recognition Pattern and Study of New Potential Biomarkers N/A
Completed NCT01751048 - LEISH-F3 + GLA-SE and the LEISH-F3 + MPL-SE Vaccine Phase 1
Terminated NCT06124144 - Safety and Drug Absorption of Orally Administered Oleylphosphocholine (OlPC) in Healthy Adults Phase 1
Completed NCT00662012 - Sodium Stibogluconate Treatment of Leishmaniasis Phase 2
Completed NCT03993093 - Prevalence of HIV +ve Cases With AIDS Defining Opportunistic Infections Among ART Naive Patients Attending ART Centre
Recruiting NCT03784248 - Mediterranean Visceral Leishmaniasis With Leishmania Infantum
Withdrawn NCT02429505 - Treatment of Leishmaniasis With Impavido® (Miltefosine): Higher-Weight Patient Registry
Completed NCT01377974 - Clinical Trial of Miltefosine to Treat Mucosal Leishmaniasis Phase 2
Completed NCT02656797 - Topical Liposomal Amphotericin B Gel Treatment for Cutaneous Leishmaniasis Phase 2
Completed NCT01484548 - Phase 1 LEISH-F3 Vaccine Trial in Healthy Adult Volunteers Phase 1
Completed NCT01300975 - Intralesional Antimony for Bolivian Cutaneous Leishmaniasis Phase 2
Completed NCT03294161 - Fourth-generation Immucillin Derivative DI4G Associated Therapy in Cutaneous Leishmaniasis Phase 2
Completed NCT00401557 - Mechanisms Relating to the Distinct in Vitro Susceptibility of Human Macrophages to L. Viannia Infection