Safety and Immunogenicity of a Human Hookworm Candidate Vaccine With or Without Additional Adjuvant in Brazilian Adults

Inclusion Criteria:

• Males or females between 18 and 45 years, inclusive.
• Good general health as determined by means of the screening procedure.
• Available for the duration of the trial (42 weeks).
• Willingness to participate in the study as evidenced by signing the informed consent document.
• If found to be infected with hookworm during screening, has completed a course of three doses of albendazole.

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, 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 <3000/mm3 or >12.5 x 103/mm3; hemoglobin <10.3 g/dl or <11.0 g/dl [females in Americaninhas and Belo Horizonte, respectively] or <11.0 g/dl or <12.0 [males in Americaninhas and Belo Horizonte, respectively); absolute lymphocyte count <900/mm3; or platelet count <120,000/mm3).
• Laboratory evidence of a coagulopathy (PTT or PT INR greater than 1.1-times the upper reference limit [in Belo Horizonte] or PT INR greater than 1.3 [Americaninhas]).
• Serum glucose (random) greater than 1.2-times the upper reference limit.
• 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.
• Positive ELISA for HIV.
• 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.
• History of allergy to yeast.
• Anti-Na-GST-1 IgE antibody level above 0.35 kUA/L by the ImmunoCAP method.
• For Part I only: history of previous infection with hookworm; residence for more than 6 months in a hookworm-endemic area; or, positive for hookworm infection on screening microscopic fecal examination.
• For Part II only: previous receipt of a primary series of any hepatitis B vaccine.