A Study of AdCh63 AMA1 Alone and With MVA AMA1

University of Oxford

Status and phase

Completed

Phase 1

Conditions

Malaria

Treatments

Biological: AdCh63 AMA1

Biological: AdCh63 AMa1 and MVA AMA1

Study type

Interventional

Funder types

Other

Identifiers

NCT01095055

VAC036

Details and patient eligibility

About

This is an open label phase I study, to assess the safety of a novel malaria vaccine, AdCh63 AMA1, simian adenovirus encoding Plasmodium falciparum blood stage antigen, Apical Membrane Antigen -1. All volunteers recruited will be healthy adults. They will be primed with various doses of AdCh63 AMA1 administered intramuscularly. Some of the volunteers will receive a booster vaccination with MVA AMA1 administered via intramuscular route. Safety data will be collected for each of the eight regimens. Secondary aims of this study will be to assess the immune responses generated by each of these regimes.

Full description

AMA1 is a type I integral membrane protein. It is produced by mature P. falciparum schizonts in infected erythrocytes AMA1 has become a leading candidate vaccine antigen. This is based on several facts, most notably that in several field studies an association was found between antibodies to the ectodomain of AMA1 and protection against clinical malaria. Also, in the Gambia, presence of antibodies to AMA1 and MSP-1 has been shown to enhance clearance of chloroquine resistant parasites in vivo.

There are a number of trials currently ongoing in Oxford which are aimed at examining a simian adenovirus as a delivery vehicle and liver and blood stage malaria antigens as inserts. AdCh63 is currently in use with the MSP-1 insert, a blood stage antigen, in a phase I dose escalation clinical trial in Oxford (VAC037 / GTAC 166). The trial design includes AdCh63 MSP-1 administered alone and with MVA MSP-1 as part of a heterologous prime boost schedule, with sporozoite challenge of 3 volunteers in the higher dose group. At the most recent interim analysis, AdCh63 MSP-1 demonstrates an excellent safety profile.

Also, AdCh63 is currently in use with the ME-TRAP insert, a liver stage antigen in a phase I dose escalation clinical trial in Oxford, (VAC033 / GTAC133) and a phase I/IIa trial with sporozoite challenge (MAL034 / OXREC: 09/H064/9). AdCh63 ME-TRAP has been administered alone and with MVA ME-TRAP as part of a heterologous prime boost schedule at various doses with excellent safety and immunogenicity to 87 volunteers at time of interim analysis.

Enrollment

16 estimated patients

Sex

All

Ages

18 to 50 years old

Volunteers

Accepts Healthy Volunteers

Inclusion criteria

Healthy adults aged 18 to 50 years

Able and willing (in the Investigator's opinion) to comply with all study requirements
Willing to allow the investigators to discuss the volunteer's medical history with their General Practitioner
For females only, willingness to practice continuous effective barrier contraception during the study and a negative pregnancy test on the day(s) of vaccination
For males only to use barrier contraception until three months after the last vaccination
Agreement to refrain from blood donation during the course of the study
Written informed consent

Exclusion criteria

Participation in another research study involving an investigational product in the 30 days preceding enrolment, or planned use during the study period

Prior receipt of a recombinant adenoviral vaccine.
Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccine candidate
Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed)
History of allergic disease or reactions likely to be exacerbated by any component of the vaccine, e.g. egg products, Kathon.
History of clinically significant contact dermatitis
Any history of anaphylaxis in reaction to vaccination
Pregnancy, lactation or willingness/intention to become pregnant during the study
History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ)
History of serious psychiatric condition
Any other serious chronic illness requiring hospital specialist supervision
Suspected or known current alcohol abuse as defined by an alcohol intake of greater than 42 units every week
Suspected or known injecting drug abuse
Seropositive for hepatitis B surface antigen (HBsAg)
Seropositive for hepatitis C virus (antibodies to HCV)
Any other significant disease, disorder or finding, which, in the opinion of the Investigator, may either put the volunteer at risk because of participation in the study, or may influence the result of the study, or the volunteer's ability to participate in the study.
Any history of malaria or
Travel to a malaria endemic region during the study period or within the previous six months
Any clinically significant abnormal finding on screening biochemistry or haematology blood tests or urinalysis
Any other finding which in the opinion of the investigators would significantly increase the risk of having an adverse outcome from participating in the protocol.