Phase II AMA-1 Malaria Vaccine FMP2.1/AS02A Trial in Mali

Phase 2

Completed

Conditions: Plasmodium Falciparum Malaria

Interventions: Biological: Rabies Vaccine
Biological: FMP2.1/AS02A

Registration Number: NCT00460525

Lead Sponsor: U.S. Army Medical Research and Development Command

Brief Summary: Malaria is a disease that affects many people in Africa. Malaria is caused by germs spread by mosquito bites. The purpose of this study is to compare the number of children who get malaria after receiving an experimental malaria vaccine (FMP2.1/AS02A) to the number of children who get malaria after receiving a vaccine for rabies (an approved vaccine that does not prevent malaria). The children will be assigned to one of the vaccine groups by chance. Participants and doctors will not know which vaccine was given. Study participants will include 400 children, ages 1-6 years, living in Bandiagara, Mali. Children will receive 3 vaccine doses, by injection, to their upper arm. Study procedures will include physical exams and several blood samples. Participants will be involved in the study for 26 months.

Detailed Description: This is a randomized, controlled, phase II clinical trial to evaluate the efficacy, safety and immunogenicity of the apical membrane antigen-1 of Plasmodium (P.) falciparum (AMA-1) malaria vaccine FMP2.1/AS02A using rabies vaccine as a control in healthy children 1-6 years old in Bandiagara, Mali. This study is linked to DMID protocol 05-0146, which is a phase I dose escalation trial at the same site in the same population. In this study, 400 subjects will be randomized in a 1:1 ratio to receive either 50 micrograms of FMP2.1 in 0.5 mL AS02A or rabies vaccine. Immunizations will be given on days 0, 30 and 60. Solicited adverse events will be recorded on the days of immunization and at 1, 2, 3 and 7 days after each immunization. Unsolicited adverse events will be recorded for 30 days after each immunization. Passive case detection will be used to capture clinical malaria episodes and adverse events including serious adverse events, and will occur by continuous availability of clinical care in a population with high utilization of this care. Active surveillance will be used to capture malaria infections and adverse events including serious adverse events. For active case detection, following the third dose, participants will be followed monthly for 6 months and then at 12, 18 and 24 months after randomization, for clinical assessment, malaria smear and hemoglobin. Routine monthly malaria smears will not be read immediately unless symptoms are present. Children will be followed for 2 years after the first immunization. Sera will be collected for anti-FMP2.1 antibody titers on the days of immunization and 1, 3, 6, 8, 12, 18 and 24 months after the first immunization. Peripheral blood mononuclear cells (PBMCs) will be collected on the days of immunization, 30 days after the third immunization and 8, 12, 18 and 24 months after the first immunization. The study Final Report will be based on data collected up to 6 months after the assigned date of the third immunization. A supplemental report will include data from the entire 24-month observation period. Primary study objectives are to: determine the efficacy of FMP2.1/AS02A in children aged 1-6 years against first clinical malaria episodes (axillary temperature of greater than or equal to 37.5 degrees Celsius and parasitemia of greater than or equal to 2500/mm\^3) occurring between randomization and 6 months after the assigned date of the third immunization; and assess the safety of the vaccine in children aged 1-6 years. Secondary study objectives are to: describe the dynamics of anti-AMA-1 antibody responses in recipients of the malaria vaccine compared to natural responses in the control group; determine whether serum anti-AMA-1 IgG titer by enzyme linked immunosorbent assay (ELISA) 1 month after the third immunization correlates with protection against clinical malaria episode; measure allele-specific efficacy against parasites with AMA-1 genotypes homologous to and heterologous to the 3D7 clone of P. falciparum; determine vaccine efficacy against clinical malaria episodes occurring between randomization and 6 months after the assigned date of the third immunization; and if efficacy is observed based on the primary endpoint, to determine vaccine efficacy against first clinical malaria episode and all clinical episodes (using increasing parasitemia thresholds) occurring during 2 years after randomization.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 400

Inclusion Criteria

Age 1-6 years inclusive at the time of screening
Residing in Bandiagara town
Appear to be in generally good health based on clinical and laboratory investigation
Separate written informed consent obtained from the parent/guardian before screening and study start, respectively
Available to participate in follow-up for the duration of study (26 months)

Exclusion Criteria

Previous vaccination with an investigational vaccine or a rabies vaccine
Use of an investigational or non-registered drug or vaccine other than the study vaccine(s) within 30 days preceding the first study immunization, or planned use up to 30 days after the third immunization
Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within six months prior to the first immunization. This exclusion includes any dose level of oral steroids or inhaled steroids, but not topical steroids.
Confirmed or suspected immunosuppressive or immunodeficient condition, including human immunodeficiency virus (HIV) infection
Confirmed or suspected autoimmune disease
History of allergic reactions or anaphylaxis to immunizations or to any vaccine component
History of serious allergic reactions to any substance, requiring hospitalization or emergent medical care
History of allergy to tetracycline, doxycycline, nickel, Imidazole, eggs, neomycin, chlortetracycline or amphotericin B
History of splenectomy
Laboratory evidence of liver disease (alanine aminotransferase [ALT] greater than the upper limit of normal of the testing laboratory = 49.6 U/L)
Laboratory evidence of renal disease (serum or plasma creatinine greater than 62 micro mol/L), or more than trace protein or blood on urine dipstick testing)
Laboratory evidence of hematologic disease (absolute leukocyte count <5,300/mm^3 or >15,300/mm^3, absolute lymphocyte count <2,300 mm^3, platelet count <133,000/mm^3, or hemoglobin <9.0 g/dL)
Hepatitis B surface antigen positive
Chronic skin condition that could interfere with vaccine site reactogenicity assessment
Administration of immunoglobulins and/or any blood products within the three months preceding the first study immunization or planned administration during the study period
Simultaneous participation in any other interventional clinical trial
Acute or chronic pulmonary, cardiovascular, hepatic (including hepatomegaly), renal or neurological condition, severe malnutrition, or any other clinical findings that in the opinion of the PI may increase the risk of participating in the study
Other condition that in the opinion of the Principal Investigator (PI) would jeopardize the safety or rights of a participant in the trial or would render the participant unable to comply with the protocol

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Rabies Vaccine	Rabies Vaccine	Rabies vaccine administered on Days 0, 30, and 60.
FMP2.1/AS02A	FMP2.1/AS02A	50 mcg of FMP2.1 in 0.5 mL AS02A administered on Days 0, 30, and 60.

Primary Outcome Measures

Name	Time	Method
Number of Unsolicited Non-serious Adverse Events Reported During the 30-day Surveillance Period After the Second Vaccination	Day 0-29 after second vaccination	Unsolicited non-serious adverse events reported are those occurring within 30 days after vaccination. The categories are the MedDRA System Organ Classes for which at least one adverse event was reported. All non-serious adverse events are included, regardless of severity or relationship to vaccination.
Number of Unsolicited Non-serious Adverse Events Reported During the 30-day Surveillance Period After the Third Vaccination	Day 0-29 after third vaccination	Unsolicited non-serious adverse events reported are those occurring within 30 days after vaccination. The categories are the MedDRA System Organ Classes for which at least one adverse event was reported. All non-serious adverse events are included, regardless of severity or relationship to vaccination.
Number of Subjects Reporting Solicited Adverse Events During the 7-day Surveillance Period After the First Vaccination	0-7 days after first vaccination	Solicited symptoms were recorded by study staff at clinic visits on Days 0, 1, 2 and 7 after each vaccination. "Reported Limitation of Arm Motion" refers to the parents' report of the symptom while "Limitation of Arm Motion" refers to the clinicians' assessment of the symptom, collected separately.
Number of Subjects Reporting Solicited Adverse Events During the 7-day Surveillance Period After the Second Vaccination.	0-7 days after the second vaccination	Solicited symptoms were recorded by study staff at clinic visits on Days 0, 1, 2 and 7 after vaccination. "Reported Limitation of Arm Motion" refers to the parents' report of the symptom while "Limitation of Arm Motion" refers to the clinicians' assessment of the symptom, collected separately.
Number of Subjects Reporting Solicited Adverse Events During the 7-day Surveillance Period After the Third Vaccination.	0-7 days after the third vaccination	Solicited symptoms were recorded by study staff at clinic visits on Days 0, 1, 2 and 7 after vaccination. "Reported Limitation of Arm Motion" refers to the parents' report of the symptom while "Limitation of Arm Motion" refers to the clinicians' assessment of the symptom, collected separately.
Number of Unsolicited Non-serious Adverse Events Reported During the 30-day Surveillance Period After the First Vaccination	Day 0-29 after first vaccination	Unsolicited non-serious adverse events reported are those occurring within 30 days after vaccination. The categories are the MedDRA System Organ Classes for which at least one adverse event was reported. All non-serious adverse events are included, regardless of severity or relationship to vaccination.
Number of Subjects Reporting Serious Adverse Events	24 months after initial vaccination	A serious adverse event was defined as any untoward medical occurrence that results in death, is life threatening, results in persistent or significant disability/incapacity, requires in-patient hospitalization or prolongation of existing hospitalization or is a congenital anomaly/birth defect in the offspring of a study subject. In addition, important medical events that may jeopardize the participant or may require intervention to prevent one of the other outcomes listed above was considered serious.
Time to First Clinical Malaria Episode With Significant Parasitemia (2500/mm^3) and Temperature of Greater Than or Equal to 37.5 Degrees C.	Occurring between randomization and 6 months after the assigned date of the 3rd immunization.	Time to first clinical malaria episode is displayed in a life table format to display the number of subjects at risk, the number with first clinical episode and the number censored at each time point.

Secondary Outcome Measures

Name	Time	Method
Incidence Density of Clinical Malaria Episode	Between randomization and 6 months after 3rd immunization.	Clinical malaria episode was defined by significant parasitemia (2500/mm\^3) and temperature of greater than or equal to 37.5 degrees C. Event rate was determined by dividing the number of episodes (150 for the Rabies group and 121 for the FMP2.1/ASO2A group) by the number of Person Years at Risk (PYAR) (126.341 for Rabies group and 127.411 for the FMP2.1/ASO2A group).
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by Enzyme Linked ImmunoSorbent Assay (ELISA) at Day 0	Day 0	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 0 prior to the first vaccination.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 547	Day 547 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 547.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 730	Day 730 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 730.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 30.	Day 30 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 30, prior to the second vaccination.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 60.	Day 60 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 60, prior to the third vaccination.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 90.	Day 90 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 90.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 150.	Day 150 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 150.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 240.	Day 240 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 240.
Geometric Mean Titers of Anti-FMP2.1 Antibody Measured by ELISA at Day 364	Day 364 after initial vaccination	Titers of Anti-FMP2.1 antibody were determined by ELISA from sera collected at Day 364.