Safety and Immunogenicity of Pfs25M-EPA/AS01 and Pfs230D1M-EPA/AS01 Vaccines, Transmission Blocking Vaccines Against Plasmodium Falciparum, at Full and Fractional Dosing in Adults in Mali

Phase 1

Completed

Conditions: Malaria

Interventions: Biological: Pfs25M-EPA
Biological: Pfs230D1M-EPA
Biological: Engerix-B
Other: AS01
Biological: Menactra
Other: Normal Saline
Drug: Coartem

Registration Number: NCT02942277

Lead Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

Brief Summary: Background:

Researchers are looking for new ways to control and eradicate malaria. They want to test vaccines to block malaria transmission in adults in Mali. These vaccines work by inducing antibodies in a person. The antibody is then taken up with blood by a mosquito that bites the person. This blocks parasite development in the mosquito. This stops malaria transmission to another person.

Objective:

To test the safety, reactogenicity, immunogenicity, and transmission-blocking activity of the vaccines Pfs25M-EPA and Pfs230D1M-EPA with AS01 in Malian adults.

Eligibility:

Healthy Malians ages 18-50 living in certain areas in Mali who:

Are not pregnant or breastfeeding

Are not infected with HIV, Hepatitis B and Hepatitis C

Do not have evidence of immunodeficiency

Do not have history of severe allergic reaction or anaphylaxis

Design:

Participants will be screened with:

Medical history

Physical exam

Malaria Comprehension Exam

Blood and urine tests

Electrocardiogram (for participants in certain study groups)

Participants will be randomly assigned to a study group.

Participants will be monitored for 12-16 months. For the first 7 months, they will have between 1 and nine visits a month. The number depends on the month and on what group they are in. For the rest of the months, they will have 1 monthly visit.

Each visit includes a physical exam. Most include blood tests.

Participants will get 3 doses of a study or comparator vaccine. They get the vaccine through an injection in the upper arm. This occurs at their first visit, then 1 month later, and then 5 months later.

Participants will be followed for at least 6 months after the last vaccine.

If participants develop an injection site rash or reaction, photographs may be taken of the site.

Detailed Description: A vaccine to interrupt malaria transmission (VIMT) would be a valuable tool for local elimination or eradication of this disease, and may contain components that block transmission to mosquitoes (such as Pfs25 or Pfs230) or that prevent human infection (such as the vaccine RTS,S). Pfs25 and Pfs230, surface antigens of zygotes and ookinetes (and gametocytes for Pfs230) in the mosquito stage of P. falciparum, are the lead candidates for a malaria transmission blocking vaccine (TBV). Recombinant Pfs25M and recombinant Pfs230D1M have each been conjugated to P. aeruginosa ExoProtein A (EPA) and adjuvanted with AS01. Our ongoing experience with Pfs25M-EPA and Pfs230D1M-EPA in Malian adult trial participants, and the extensive experience with the AS01 adjuvants in African children and adults, justify conducting the first-in-human trial of Pfs25M-EPA and Pfs230D1M-EPA with AS01 in Malian adults. This dose-escalating phase 1 study will determine safety, immunogenicity, and functional activity of these vaccines in Malian adults. Pfs25M-EPA + Pfs230D1M-EPA in AS01 will be assessed by mosquito feeding assays in Malian adults for evidence that they may reduce the number of malaria transmission events in study subjects.

A total of 305 subjects will be enrolled at multiple sites in Mali, West Africa to receive escalating doses of a malaria transmission blocking vaccine (s): Pfs25M-EPA/AS01, Pfs230D1M-EPA/AS01, or simultaneous administration of Pfs25M-EPA/AS01 and Pfs230D1M-EPA/AS01; or a comparator vaccine (ENERGIX-B). Enrollment within each group will be staggered for additional safety and subjects will only be enrolled into the co-administration group once each individual dose has been administered. Subjects will be followed for at least 6 months after the last vaccination. Safety outcomes will be local and systemic adverse events and serious adverse events. Immunogenicity outcomes will be antibody responses as measured by ELISA against recombinant Pfs25, Pfs230, EPA, CSP, and B cell and T cell responses. Functional activity of the induced antibodies will be assessed in TBV arms by standard membrane feeding assays conducted at the National Institute of Allergy and Infectious Diseases, and activity that interrupts malaria transmission will be measured in all arms by direct skin feeding assays in Mali.

Subjects in the open label safety cohorts (Arms 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b) will be offered reenrollment for follow-up laboratory assessment to explore the duration of immunogenicity and functional activity at approximately 9, 12 months post vaccination. Following scheduled, intentional unblinding, subjects enrolled in Arms 2c, 2d, and 4c will be provided the opportunity to re-enroll for a fourth vaccination (Arm 2c and 2d with 40 microgram dose of Pfs230D1M-EPA/AS01; Arm 4c with Menatctra) approximately 1 year post vaccination #3. Subjects in these arms will also be eligible to re-enroll for follow up of duration of immunogenicity and functional activity at approximately 9, 12 months post vaccination if they choose not to enroll to recive the booster vaccination. Subjects will be followed similarly to the previous year for safety, immunogenicity, and functional activity.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 301

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
1a	Pfs25M-EPA	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 on D0, D28, D168
1a	AS01	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 on D0, D28, D168
1a	Normal Saline	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 on D0, D28, D168
1b	Pfs25M-EPA	(n=10), to receive 47 microgram Pfs25M-EPA/AS01 on D0, D28, D168
1b	AS01	(n=10), to receive 47 microgram Pfs25M-EPA/AS01 on D0, D28, D168
2a	Pfs230D1M-EPA	(n=5), to receive 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
2a	AS01	(n=5), to receive 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
2a	Normal Saline	(n=5), to receive 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
2c	AS01	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 on D0, D28, D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
2b	Pfs230D1M-EPA	(n=10), to receive 40 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
2b	AS01	(n=10), to receive 40 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
2c	Pfs230D1M-EPA	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 on D0, D28, D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
2d	AS01	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 (500 (Micro)L TBV + AS01) on D0, D28, then 8 micro liters Pfs230D1M- EPA/AS01 (100 (Micro)L TBV + AS01;fractional dose) on D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
3a	Pfs25M-EPA	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 and 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
3a	Pfs230D1M-EPA	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 and 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
3a	AS01	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 and 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
3a	Normal Saline	(n=5), to receive 16 microgram Pfs25M-EPA/AS01 and 13 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168
3b	Pfs25M-EPA	(n=10), to receive 47 microgram Pfs25M-EPA/AS01 and 40 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168 (Bamako)
3b	Pfs230D1M-EPA	(n=10), to receive 47 microgram Pfs25M-EPA/AS01 and 40 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168 (Bamako)
3b	AS01	(n=10), to receive 47 microgram Pfs25M-EPA/AS01 and 40 microgram Pfs230D1M-EPA/AS01 on D0, D28, D168 (Bamako)
4a	Engerix-B	(n=10), to receive ENGERIX-B on D0, D28, and D168
4a	Normal Saline	(n=10), to receive ENGERIX-B on D0, D28, and D168
4c	Menactra	(n=120), to receive ENGERIX-B on D0, D28, and D168 (start study with Arm 2c and 2d); all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); vaccination with Menactra on D476
2d	Pfs230D1M-EPA	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 (500 (Micro)L TBV + AS01) on D0, D28, then 8 micro liters Pfs230D1M- EPA/AS01 (100 (Micro)L TBV + AS01;fractional dose) on D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
4b	Engerix-B	(n=10), to receive ENGERIX-B on DO, D28, and Dl68
4c	Engerix-B	(n=120), to receive ENGERIX-B on D0, D28, and D168 (start study with Arm 2c and 2d); all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); vaccination with Menactra on D476
2c	Coartem	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 on D0, D28, D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
2d	Coartem	(n=60), to receive 40 micrograms Pfs230D1M-EPA/AS01 (500 (Micro)L TBV + AS01) on D0, D28, then 8 micro liters Pfs230D1M- EPA/AS01 (100 (Micro)L TBV + AS01;fractional dose) on D168; all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); 4th vaccination on D476
4b	Coartem	(n=10), to receive ENGERIX-B on DO, D28, and Dl68
4c	Coartem	(n=120), to receive ENGERIX-B on D0, D28, and D168 (start study with Arm 2c and 2d); all subjects will undergo antimalarial drug treatment with Coartem on D-7 (prior to vaccination #1); vaccination with Menactra on D476

Primary Outcome Measures

Name	Time	Method
Number of Participants With Local and Systemic Adverse Events in Year 2	Within 7 days after each vaccination	Number of participants with local and systemic adverse events (AEs) graded by severity occurring within 7 days after each vaccine
Number of Participants With Local and Systemic Adverse Events in Year 1	Within 7 days after each vaccination	Number of participants with local and systemic adverse events (AEs) graded by severity occurring within 7 days after each vaccine

Secondary Outcome Measures