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

Primary Purpose

Hookworm Infection

Status
Recruiting
Phase
Phase 1
Locations
United States
Study Type
Interventional
Intervention
Necator americanus Hookworm Larvae
Sponsored by
Baylor College of Medicine
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional other trial for Hookworm Infection focused on measuring Necator americanus, Hookworm Infection, Experimental challenge infection

Eligibility Criteria

18 Years - 45 Years (Adult)All SexesAccepts Healthy Volunteers

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.

Sites / Locations

  • George Washington University Medical Faculty AssociatesRecruiting

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm Type

Experimental

Experimental

Experimental

Arm Label

25 Necator americanus Hookworm Larvae

50 Necator americanus Hookworm Larvae

75 Necator americanus Hookworm Larvae

Arm Description

Outcomes

Primary Outcome Measures

Study product-related adverse events
Frequency of study product-related adverse events, graded by severity, for different doses of N. americanus Larval Inoculum.

Secondary Outcome Measures

Fecal egg counts
To determine the dose of N. americanus Larval Inoculum that generates the highest fecal egg counts, measured by fecal microscopy.
Number of adult hookworms in feces post-treatment
To compare the N. americanus Larval Inoculum dose received with the number of adult worms present in the gut, as determined by capsule endoscopy.

Full Information

First Posted
September 9, 2013
Last Updated
October 10, 2023
Sponsor
Baylor College of Medicine
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1. Study Identification

Unique Protocol Identification Number
NCT01940757
Brief Title
Experimental Infection of Hookworm-naïve Adults With Dermally-applied Infectious Necator Americanus Hookworm Larvae
Official Title
An Experimental Infection Study of Dermally-applied Infectious Necator Americanus Hookworm Larvae in Hookworm-naïve Adults
Study Type
Interventional

2. Study Status

Record Verification Date
October 2023
Overall Recruitment Status
Recruiting
Study Start Date
January 2015 (Actual)
Primary Completion Date
September 2024 (Anticipated)
Study Completion Date
February 2025 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Baylor College of Medicine

4. Oversight

Data Monitoring Committee
Yes

5. Study Description

Brief Summary
An experimental hookworm infection model is being developed to provide early proof-of-concept that a hookworm vaccine targeting the blood-feeding pathway of adult hookworms is feasible and efficacious. The proposed model consists of vaccinating healthy, hookworm-naïve adults with a candidate hookworm vaccine, followed by challenging them with the investigational product, Necator americanus Larval Inoculum to assess the effect of vaccination on infection. The first proposed study will be a feasibility study that will consist of administering different doses of the Necator americanus Larval Inoculum to healthy adult volunteers to determine the optimal dose (i.e., number of infectious larvae) that is safe, well-tolerated and results in consistent infection.
Detailed Description
Open-label, dose-escalation clinical study in healthy, hookworm-naïve adults: Study site: George Washington Medical Faculty Associates, Washington, DC Number of participants: up to 30 in 3 cohorts of 10 volunteers each In Cohort 1, ten (10) volunteers will receive an inoculum of 25 infectious Necator americanus larvae. In Cohort 2, ten (10) volunteers will receive an inoculum of 50 infectious Necator americanus larvae. In the optional Cohort 3, ten (10) volunteers will receive an inoculum of 75 infectious Necator americanus larvae. The cohorts will be enrolled in a staggered fashion with safety data assessed prior to larval dose escalation. Cohort 2 will be inoculated no earlier than 8 weeks after the last volunteer is inoculated in Cohort 1. The optional Cohort 3 will be inoculated no sooner than 8 weeks after the last volunteer is inoculated in Cohort 2. Cohort 3 will be enrolled only if the tolerability of the experimental infection of Cohort 2 is acceptable and does not result in significant adverse events. Within each cohort, after Study Day 70, but before Study Day 77, up to 5 volunteers will undergo capsule endoscopy in order to visualize and count adult N. americanus hookworms residing in the intestine. Informed consent for capsule endoscopy will be obtained separately from the primary study, and agreement or refusal will not impact on a subject's eligibility to enroll or continue participation in the primary study. Three months after larval administration, or at the time of study withdrawal, all participants will receive a 3-dose treatment of albendazole (400 mg per dose) for clearance of experimental infection. Larval inoculum schedule: Study Day 0 (single application) Route: applied to intact skin on the volar aspect of forearm Doses of N. americanus Larval Inoculum to be tested: 25, 50 and 75 infectious larvae (high dose optional) Study duration: 6 months per study participant; total duration of the study estimated at approximately 13 months Anthelmintic treatment: 3 months post larval inoculum, or at study withdrawal, 3-dose treatment with 400 mg albendazole

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Hookworm Infection
Keywords
Necator americanus, Hookworm Infection, Experimental challenge infection

7. Study Design

Primary Purpose
Other
Study Phase
Phase 1
Interventional Study Model
Parallel Assignment
Masking
None (Open Label)
Allocation
Non-Randomized
Enrollment
28 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
25 Necator americanus Hookworm Larvae
Arm Type
Experimental
Arm Title
50 Necator americanus Hookworm Larvae
Arm Type
Experimental
Arm Title
75 Necator americanus Hookworm Larvae
Arm Type
Experimental
Intervention Type
Biological
Intervention Name(s)
Necator americanus Hookworm Larvae
Other Intervention Name(s)
Na-L3
Intervention Description
Infectious larvae of the human hookworm Necator americanus
Primary Outcome Measure Information:
Title
Study product-related adverse events
Description
Frequency of study product-related adverse events, graded by severity, for different doses of N. americanus Larval Inoculum.
Time Frame
Up to 6 months after dosing
Secondary Outcome Measure Information:
Title
Fecal egg counts
Description
To determine the dose of N. americanus Larval Inoculum that generates the highest fecal egg counts, measured by fecal microscopy.
Time Frame
Up to Study Day 101
Title
Number of adult hookworms in feces post-treatment
Description
To compare the N. americanus Larval Inoculum dose received with the number of adult worms present in the gut, as determined by capsule endoscopy.
Time Frame
Study Days 87-101

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
45 Years
Accepts Healthy Volunteers
Accepts Healthy Volunteers
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.
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
Study Coordinator
Phone
(202) 994-1599
Email
gwvru@gwu.edu
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
David J Diemert, MD
Organizational Affiliation
George Washington University
Official's Role
Principal Investigator
Facility Information:
Facility Name
George Washington University Medical Faculty Associates
City
Washington
State/Province
District of Columbia
ZIP/Postal Code
20037
Country
United States
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Study Coordinator
Phone
202-994-1599
Email
gwvru@gwu.edu
First Name & Middle Initial & Last Name & Degree
Aimee Desrosiers, PA
First Name & Middle Initial & Last Name & Degree
Elissa Malkin, DO, MPH
First Name & Middle Initial & Last Name & Degree
Caroline Thoreson, PA

12. IPD Sharing Statement

Citations:
PubMed Identifier
29780848
Citation
Diemert D, Campbell D, Brelsford J, Leasure C, Li G, Peng J, Zumer M, Younes N, Bottazzi ME, Mejia R, Pritchard DI, Hawdon JM, Bethony JM. Controlled Human Hookworm Infection: Accelerating Human Hookworm Vaccine Development. Open Forum Infect Dis. 2018 Apr 19;5(5):ofy083. doi: 10.1093/ofid/ofy083. eCollection 2018 May.
Results Reference
derived

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

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