Experimental Infection of Hookworm-naïve Adults With Dermally-applied Infectious Necator Americanus Hookworm Larvae

Launched by BAYLOR COLLEGE OF MEDICINE · Sep 9, 2013

Keywords

ClinConnect Summary

This clinical trial is studying a new vaccine aimed at preventing hookworm infections, which are caused by tiny worms that can enter the body through the skin. The researchers want to see if this vaccine can effectively protect healthy adults who have never been infected with hookworms before. In the first part of the study, volunteers will receive different doses of hookworm larvae to find out which dose is safe and leads to an infection, allowing scientists to assess the vaccine's effectiveness.

To participate in this trial, you need to be between 18 and 45 years old, in good overall health, and available for about six months. Women who are pregnant, breastfeeding, or not using reliable birth control cannot join. Participants will be closely monitored throughout the study, and they will need to sign a consent form agreeing to take part. This trial is important because it could help develop a vaccine that protects against hookworm infections, which can cause health problems, especially in tropical and subtropical areas.

Gender

ALL

Eligibility criteria

• 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 (6 months).
• • Willingness to participate in the study as evidenced by signing the informed consent document.
• Exclusion Criteria:
• • Pregnancy as determined by a positive urine human choriogonadotropin (hCG) (if female).
• • Participant unwilling to use reliable contraception methods while participating in the study (if female and not surgically sterile, abstinent or at least 2 years post-menopausal).
• • Currently lactating and breast-feeding (if female).
• • 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 (hemoglobin \<11.5 g/dl \[females\] or \<12.5 g/dl \[males\]; absolute leukocyte count \<3.6 or \>10.7 x 103/mm3; absolute neutrophil count \[ANC\] \<1.7 x 103/mm3; absolute lymphocyte count \<0.7 x 103/mm3; or platelet count \<140 x 103/mm3).
• • History of iron deficiency anemia.
• • History of hypoalbuminemia.
• • Laboratory evidence of a coagulopathy (PTT or PT INR greater than 1.1-times the upper reference limit).
• • 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.
• • 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 clinic visit or hospitalization within 6 months of the volunteer's expected Day 0 of the study.
• • Positive ELISA for hepatitis B surface antigen (HBsAg).
• • Positive confirmatory test for HIV infection.
• • Positive confirmatory test for hepatitis C virus (HCV) infection.
• • Use of corticosteroids (excluding topical or nasal) or immunosuppressive drugs within 30 days of the volunteer's expected Day 0 of this study or planned use during the study.
• • Receipt of a live vaccine within 4 weeks or a killed vaccine within 2 weeks prior to the volunteer's expected Day 0 of the study.
• • Receipt of blood products within the past 6 months.
• • Known allergy to amphotericin B or gentamicin.
• • History of previous infection with hookworm or residence for more than 6 months in a hookworm-endemic area.