Safety and Immunogenicity of Co-Administered Hookworm Vaccine Candidates Na-GST-1 and Na-APR-1 in Gabonese Adults

Inclusion Criteria: * Males or females between 18 and 50 years, inclusive, who are long-term residents of Gabon. * Good general health as determined by means of the screening procedure. * Assumed availability for the duration of the trial (12 months). * Willingness to participate in the study as evidenced by signing the informed consent document. * Negative for hookworm during screening, or if found to be infected with hookworm, has completed a course of three doses of albendazole. Exclusion Criteria: * Pregnancy as determined by a positive urine hCG (if female). * Participant unwilling to use reliable contraception up until one month following the third immunization (if female and not surgically sterile, abstinent or at least 2 years post-menopausal). * Currently lactating and breast-feeding (if female). * Inability to correctly answer all questions on the informed consent comprehension questionnaire. * Evidence of clinically significant neurologic, cardiac, pulmonary, hepatic, rheumatologic, autoimmune, diabetes, or renal disease by history, physical examination, and/or laboratory studies. * Known or suspected immunodeficiency. * Laboratory evidence of liver disease (alanine aminotransferase \[ALT\] greater than 1.25-times the upper reference limit). * Laboratory evidence of renal disease (serum creatinine greater than 1.25-times the upper reference limit, or more than trace protein or blood on urine dipstick testing). * Laboratory evidence of hematologic disease (absolute leukocyte count \<3500/mm3; absolute leukocyte count \>11.0 x 103/mm3; hemoglobin \<10.000 g/dl \[females\] or \<12.0 g/dl \[males\]; or, platelet count \<140,000/mm3). * Other condition that in the opinion of the investigator would jeopardize the safety or rights of a volunteer participating in the trial or would render the subject unable to comply with the protocol. * Participation in another investigational vaccine or drug trial within 30 days of starting this study or for the duration of the study. * Volunteer has had medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 12 months. * History of a severe allergic reaction or anaphylaxis. * Severe asthma as defined by the need for daily use of inhalers or emergency room/clinic visit or hospitalization within 6 months of the volunteer's planned first vaccination in the study. * Positive for HCV * Positive ELISA for HBsAg. * Positive for HIV infection * Use of corticosteroids (excluding topical or nasal) or immunosuppressive drugs within 30 days of starting this study or expect to use for the duration of the study. * Receipt of a live vaccine within past 4 weeks or a killed vaccine within past 2 weeks prior to entry into the study. * History of a surgical splenectomy. * Receipt of blood products within the 6 months prior to entry into the study. * Previous receipt of a primary series of any hepatitis B vaccine.