ClinicalTrials.gg
CompletedNCT00120081Updated May 31, 2017

Study of Na-ASP-2 Human Hookworm Vaccine in Healthy Adults Without Evidence of Hookworm Infection

A Phase 1 interventional study of Na-ASP-2/Alhydrogel Hookworm Vaccine and Saline placebo in Hookworm Infection, sponsored by Baylor College of Medicine. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2017-05-31.

Sponsored by Baylor College of Medicine · Phase 1, Interventional, and Prevention

Phase
Phase 1
Study type
Interventional
Enrollment
36
Allocation
Randomized
Ages
18 Years to 45 Years
Sex
All
01

Study summary

The primary objective of this clinical trial is to determine the safety and tolerability of the Na-ASP-2 Hookworm Vaccine in healthy subjects following the administration of 3 intramuscular (IM) injections of the vaccine over 16 weeks using 3 different doses. The secondary objective is to make a preliminary evaluation of the immunogenicity of each of the 3 doses of the vaccine in healthy volunteers.

Read the detailed description

There is an urgent need for new tools to control human hookworm infection and to reduce its burden of disease in developing countries. This is especially true for children and women of reproductive age who represent populations that are highly vulnerable to the effects of hookworm disease. Up to 65,000 deaths annually have been attributed to human hookworm infection. However, the mortality estimates of hookworm pale in comparison to global disease burden estimates.

The primary approach to hookworm control worldwide has been the frequent and periodic use of benzimidazole anthelminthics for school-age children. However, school-based anthelminthic chemotherapy programs miss populations highly vulnerable to hookworm, including adolescent and adult women. In addition, high rates of hookworm re-infection occur within 4-12 months following anthelminthic chemotherapy, and there is evidence for diminished efficacy of benzimidazoles with frequent and periodic use, possibly because of emerging drug resistance. These concerns have prompted interest in developing alternative tools for hookworm control. Vaccination to prevent high intensity hookworm infection would alleviate the public health deficiencies of drug treatment alone.

02

Conditions studied

  • Hookworm Infection

Keywords

  • Vaccine
  • Hookworm
  • Phase 1
  • Human Hookworm Infection
  • Na-ASP-2
03

In context

Hookworm Infections

39 studies on the registry are indexed under Hookworm Infections; 5 are open to participants now.

This study's enrollment of 36 is below the median of 182 across 36 interventional studies indexed under Hookworm Infections.

Browse Hookworm Infections studies →

Lead sponsor

Baylor College of Medicine is the lead sponsor of 747 studies on the registry; 110 are open to participants now.

Of its 84 completed or terminated interventional studies of FDA-regulated products, 45 (54%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 45 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Healthy adults 18 to 45 years of age.
  • Signed .
  • History, physical exam, and laboratory tests indicating good general health obtained prior to the first injection.
  • All females must have a negative pregnancy test (FDA-approved test for β human chorionic gonadotropin [β-HCG]) on the day of the first injection.
  • Serologic tests for (HIV), surface antigen (HBsAg), and virus (HCV) are negative at screening.
  • All subjects must agree to use an acceptable method of from the start of screening until 2 weeks after the third injection. Acceptable methods for female subjects include hormonal contraceptives, intrauterine device (IUD), diaphragm with spermicide, condoms, abstinence, surgically sterile (hysterectomy), and surgically sterile partner. Acceptable methods for male subjects include surgical sterilization, condoms, partner who uses an acceptable method of birth control, and abstinence.

Exclusion criteria

Exclusion Criteria:

  • Any history of anaphylaxis or allergy to vaccine components or allergy to insect stings, including bee stings.
  • A past or current history of hookworm infection.
  • \< 18.0 or > 30.0.
  • Recent (\< 72 hours) history of febrile illness at the time of vaccination (temperature > 99.6°F or equivalent).
  • Received any immune globulin or blood product 3 months prior to injection or scheduled within 4 weeks thereafter.
  • Had vaccination with a within 4 weeks before receipt of the vaccine or scheduled within 4 weeks thereafter.
  • Had vaccination with a killed vaccine, or allergy treatment with antigen injections within 14 days of initial study injection.
  • Received an agent within 4 weeks of initial study injection.
  • Known or suspected impairment of immunologic function including, but not limited to liver disease, diabetes mellitus, moderate to severe kidney impairment (creatinine > 1.5), any history of (except squamous cell or basal cell skin cancer), infection or diseases, or concomitant medication such as glucocorticosteroids.
  • A history of essential hypertension, gastrointestinal abnormalities such as peptic ulcer disease, cardiac ( abnormalities), pulmonary, hepatic, renal, pancreatic, or neurologic disease.
  • Taken prescription medications with the exception of subjects on a stable regimen (> 30 days) of: (1) hormone replacement therapy, (2) use of nasal , (3) topical therapy, (4) certain classes of antidepressants (i.e., selective serotonin re-uptake inhibitors), (5) oral , (6) nonsteroidal anti-inflammatory agents, or (7) antihistamines or decongestants for seasonal allergies taken as needed.
  • to IM injection such as anti-coagulant therapy or thrombocytopenia.
  • Pregnant, nursing, or expecting to conceive during the study.
  • Any history of chronic alcohol or drug abuse or current treatment with any known prescribed or over-the-counter supplements that may be hepatotoxins.
  • Any subject who, in the Investigator's opinion, will be unable to adhere to protocol requirements.
Terms in these criteria, in plain language(15)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Live vaccines

Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

Autoimmune disease

A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.

Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

ECG (electrocardiogram)

A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

05

Study design

Phase
Phase 1
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Single group
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
36 participants (actual)

Study arms

  • Experimental
    Low dose

    10 mcg Na-ASP-2/Alhydrogel

    Biological: Na-ASP-2/Alhydrogel Hookworm Vaccine

  • Experimental
    Medium dose

    50 mcg Na-ASP-2/Alhydrogel

    Biological: Na-ASP-2/Alhydrogel Hookworm Vaccine

  • Experimental
    High dose

    100 mcg Na-ASP-2/Alhydrogel

    Biological: Na-ASP-2/Alhydrogel Hookworm Vaccine

  • Placebo comparator
    Saline placebo

    Saline placebo

    Biological: Saline placebo

Interventions

  • BiologicalNa-ASP-2/Alhydrogel Hookworm Vaccine

    The recombinant hookworm protein Na-ASP-2 formulated on aluminum hydroxide adjuvant (Alhydrogel), in one of three dose concentrations, compared to a saline placebo control.

  • BiologicalSaline placebo

    Inactive saline placebo control

06

What researchers measure

Primary outcomes

  1. Safety and tolerability of three different doses of the Na-ASP-2 hookworm vaccine in healthy volunteers

    Time frame: For the duration of the study

Secondary outcomes

  1. To determine the immunogenicity, both humoral and cellular, of the vaccine at specified time points following vaccination

    Time frame: 2, 8, 10, 16, 18, 24, and 48 weeks after the first injection

07

Study locations

1 site
  • George Washington University Medical Center
    Washington, D.C., District of Columbia 20037, United States
08

References and documents

Publications

  • Bethony JM, Simon G, Diemert DJ, Parenti D, Desrosiers A, Schuck S, Fujiwara R, Santiago H, Hotez PJ. Randomized, placebo-controlled, double-blind trial of the Na-ASP-2 hookworm vaccine in unexposed adults. Vaccine. 2008 May 2;26(19):2408-17. doi: 10.1016/j.vaccine.2008.02.049. Epub 2008 Mar 11. PubMed 18396361 ↗
09

Timeline

Tracking since Sep 25, 2026
Not marked actual or estimatedDates not marked actual or estimated

The record gives a start of Apr 2005, a primary completion of Sep 2006 and a completion of Sep 2006. It does not say whether these dates are actual or estimated.

How these figures are worked out, and which studies are left out of them.

Registered
Jul 7, 2005
First posted
Jul 15, 2005
Start
Apr 2005
Primary completionActual
Sep 2006
CompletionActual
Sep 2006
Last update
May 31, 2017
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on May 31, 2017, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT00120081
Collaborators
Bill and Melinda Gates Foundation
Responsible party
Maria Elena Bottazzi PhD (Principal Investigator, Baylor College of Medicine) — Principal investigator
First posted
Jul 15, 2005
Start date
Apr 2005
Primary completion
Sep 2006
Completion
Sep 2006
Last update
May 31, 2017

Study contacts

Gary Simon, M.D., Ph.D
principal investigator · George Washington University

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in May 2017. You cannot join it, but the record below documents what was studied.

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