NCT03906474

VAC063C: A Study to Assess Repeat Blood-stage P. Falciparum Infection

A Clinical Study to Assess the Safety of Primary, Secondary and Tertiary Blood-stage Controlled Human Plasmodium Falciparum Malaria Infection of Healthy Malaria-naïve UK Adults, and to Characterise Parasite Growth Dynamics

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 11 (actual)
• Sponsor: University of Oxford · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Accepted

Summary

This is a clinical study to assess the safety of primary, secondary and tertiary blood-stage controlled human Plasmodium falciparum malaria infection of healthy malaria-naïve UK adults, as well as to evaluate any effect of prior exposure to a blood-stage controlled human malaria infection (CHMI) on the parasite multiplication rate. As a secondary objective, the immune response to primary, secondary and tertiary P. falciparum blood-stage infection, as well as gametocytaemia, will also be assessed.

Detailed description

Nine to seventeen healthy adult volunteers, aged between 18 and 50 years, will be recruited and receive a blood-stage controlled human malaria infection (CHMI) at the CCVTM, Oxford. Of these volunteers, three will be newly recruited, malaria-naïve volunteers, who will receive a primary CHMI. The remaining volunteers will be invited to be involved in this study, following previous participation in the VAC063 study (ClinicalTrials.gov Identifier: NCT02927145). VAC063 was a study to assess the safety, immune responses and efficacy of the new malaria vaccine RH5.1/AS01. As part of this study, control volunteers, who did not receive a vaccine, received a blood-stage CHMI, or "challenge", in order to compare to the vaccinated volunteers. Some control (unvaccinated) participants received two challenges and some received just one challenge, therefore, in this study, participants who previously took part in VAC063 will receive either a third or second malaria challenge. Volunteers will be challenged with malaria by administering a small amount of P. falciparum infected blood intravenously. Blood will then be taken at regular intervals to measure the parasite growth, quantify the sexual parasite forms and assess the immune response to primary, secondary or tertiary P. falciparum CHMI. When volunteers are diagnosed with malaria, treatment with a standard antimalarial course of oral artemether-lumefantrine (Riamet) will be given over 3 days. Volunteers who take part in this study will be involved in the trial for approximately 3 months.

Conditions

• Malaria

Interventions

Type	Name	Description
BIOLOGICAL	Blood-stage controlled human P. falciparum malaria infection	Volunteers will be challenged with malaria by administering a small amount of P. falciparum infected blood intravenously.

Timeline

• Start date: 2018-11-06
• Primary completion: 2019-02-14
• Completion: 2019-02-14
• First posted: 2019-04-08
• Last updated: 2019-04-08

Locations

1 site across 1 country: United Kingdom