Phase 1 Trial of Na-ASP-2 Hookworm Vaccine in Previously Infected Brazilian Adults

Inclusion Criteria: * Males or females between 18 and 45 years, inclusive. * Known residents of the Municipality of Novo Oriente de Minas, Minas Gerais, Brazil. * Good general health as determined by means of the screening procedure. * Completed a 3-dose albendazole treatment for documented hookworm infection during the previous 3 months. * Available for the duration of the trial (42 weeks). * Willingness to participate in the study as evidenced by signing the informed consent document. Exclusion Criteria: * Pregnancy as determined by a positive urine β-hCG (if female). * Participant unwilling to use reliable contraception methods up until one month following the third immunization (if female). * 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, or renal disease by history, physical examination, and/or laboratory studies. * Behavioral, cognitive, or psychiatric disease that in the opinion of the investigator affects the ability of the volunteer to understand and cooperate with the study protocol. * Laboratory evidence of liver disease (alanine aminotransferase \[ALT\] greater than 64 U/l \[females\] or greater than 58 U/l \[males\]). * Laboratory evidence of renal disease (serum creatinine greater than 1.1 mg/dl \[females\] or greater than 1.3 mg/dl \[males\], or more than trace protein or blood on urine dipstick testing). * Laboratory evidence of hematologic disease (absolute leukocyte count \<3000/mm3 or \>12.5 x 103/mm3; hemoglobin \<10.3 g/dl \[females\] or \<11.0 g/dl \[males\]; absolute lymphocyte count \<900/mm3; or platelet count \<120,000/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. * 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 regular use of inhalers or emergency clinic visit or hospitalization within the last 6 months. * Positive ELISA for HCV. * Positive ELISA for HBsAg. * Known immunodeficiency syndrome. * Use of corticosteroids (excluding topical or nasal) or immunosuppressive drugs within 30 days of starting this 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 past 6 months. * Previous receipt of a primary series of any hepatitis B vaccine. * History of allergy to yeast.