ClinicalTrials.gg
CompletedNCT03373214Updated Jan 13, 2021

Na-GST-1/Alhydrogel With or Without CpG 10104 in Gabonese Adults

A Phase 1 interventional study of Na-GST-1 and CPG 10104 in Hookworm Infection and Hookworm Disease, sponsored by Baylor College of Medicine. Completed at 1 site in Gabon. Open to participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2021-01-13.

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

From the registry’s dates

  • Primary completion was Feb 2019, 7 years 8 months ago, and no results have been posted to the registry.
Phase
Phase 1
Study type
Interventional
Enrollment
24
Allocation
Randomized
Ages
18 Years to 50 Years
Sex
All
01

Study summary

Na-GST-1 is a protein expressed during the adult stage of the Necator americanus hookworm life cycle that is thought to play a role in the parasite's degradation of host hemoglobin for use as an energy source. Vaccination with recombinant Na-GST-1 has protected dogs and hamsters from infection in challenge studies. This study will evaluate the safety and immunogenicity of administering Na-GST-1 with or without the CpG 10104 immunostimulant to healthy Gabonese adults living in an area of endemic hookworm infection.

Read the detailed description

Double blind, randomized, controlled, dose-escalation Phase 1 clinical trial in hookworm-exposed adults aged 18 to 50 years living in the area of Lambaréné, Gabon. Participants will receive three doses of the assigned vaccine(s) delivered intramuscularly (deltoid) on approximately Days 0, 56, and 112.

Safety will be measured from the time of each study vaccination (Day 0) through 14 days after each study vaccination by the occurrence of solicited injection site and systemic reactogenicity events.

Unsolicited non-serious adverse events (AEs) will be collected from the time of the first study vaccination through approximately 1 month after each study vaccination. New-onset chronic medical conditions and Serious Adverse Events (SAEs) will be collected from the time of the first study vaccination through approximately 9 months after the final study vaccination (final visit). Clinical laboratory evaluations for safety will be performed on venous blood collected approximately 14 days after each vaccination.

Immunogenicity testing will include IgG antibody responses to each vaccine antigen, by a qualified indirect enzyme-linked immunosorbent assay (ELISA), on serum or plasma obtained prior to each study vaccination and at time points after each vaccination; the functional activity of vaccine-induced antibodies will be assessed by in vitro enzyme neutralization assays.

Recruitment and enrollment into the study will occur on an ongoing basis, with each group being recruited and vaccinated in sequence.

24 subjects will be enrolled into 2 groups:

  • Group 1 (n=12):

    • 8 subjects will receive 30 µg Na-GST-1 plus 500 µg CPG 10104 delivered by IM injection in the deltoid muscle
    • 4 subjects will receive 100 µg Na-GST-1 delivered by IM injection in the deltoid muscle
  • Group 2 (n=12):

    • 8 subjects will receive 100 µg Na-GST-1 plus 500 µg CPG 10104 delivered by IM injection in the deltoid muscle
    • 4 subjects will receive 100 µg Na-GST-1 delivered by IM injection in the deltoid muscle
02

Conditions studied

  • Hookworm Infection
  • Hookworm Disease

Keywords

  • Human Hookworm
  • Necator americanus
  • Hookworm
  • Hookworm Disease
  • Iron-deficiency anemia
  • Soil-transmitted helminth infection
  • Neglected Tropical Disease
  • Na-GST-1
  • CpG
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 24 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 50 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

  1. Males or females between 18 and 50 years, inclusive, who are long-term residents of the study area.
  2. Good general health as determined by means of the screening procedure.
  3. Assumed availability for the duration of the trial (13 months).
  4. Willingness to participate in the study as evidenced by signing the document.
  5. Negative for hookworm during screening, or if found to be infected with hookworm, has completed a course of three doses of albendazole.

Exclusion criteria

Exclusion Criteria:

  1. Pregnancy as determined by a positive urine human choriogonadotropin (hCG) test (if female).
  2. Participant unwilling to use reliable up until one month following the final immunization (if female and not surgically sterile, abstinent, at least 2 years , or determined otherwise by medical evaluation to be sterile).
  3. Currently lactating and breast-feeding (if female).
  4. Inability to correctly answer all questions on the comprehension questionnaire.
  5. Evidence of neurologic, cardiac, pulmonary, hepatic, rheumatologic, , diabetes, or renal disease by history, physical examination, and/or laboratory studies.
  6. Has a diagnosis of schizophrenia, bipolar disease or other major psychiatric condition that would make compliance with study visits/procedures difficult (e.g., subject with psychoses or history of suicide attempt or gesture in the 3 years before study entry, ongoing risk for suicide).
  7. Known or suspected immunodeficiency.
  8. Laboratory evidence of liver disease ( [ALT] greater than 1.25-times the upper reference limit).
  9. Laboratory evidence of renal disease (serum creatinine greater than 1.25-times the upper reference limit, or more than 1+ protein, or glucose on urine dipstick testing).
  10. Laboratory evidence of hematologic disease (absolute leukocyte count \<3500/mm3; absolute leukocyte count >11.0 x 103/mm3; \<10.0 g/dl [females] or \<12.0 g/dl [males]; or, count \<140,000/mm3).
  11. Other condition that in the opinion of the investigator could jeopardize the safety or rights of a volunteer participating in the trial or would render them unable to comply with the protocol.
  12. Participation in another vaccine or drug trial within 30 days of starting this study or for the duration of the study.
  13. History of a severe allergic reaction or anaphylaxis.
  14. Severe asthma as defined by the need for daily use of inhalers or emergency room/clinic visit or hospitalization within 6 months of the volunteer's planned first vaccination in the study.
  15. Positive for .
  16. Positive for .
  17. Positive for infection.
  18. Use of (excluding topical or nasal) or drugs within 30 days of starting this study or planned use up to one month after the volunteer's final vaccination.
  19. Receipt of a within past 4 weeks or a killed vaccine within past 2 weeks prior to entry into the study.
  20. History of a surgical splenectomy.
  21. Receipt of blood products within the 6 months prior to entry into the study.
  22. Previous receipt of the Na-GST-1/Alhydrogel® vaccine.
  23. Pre-existing autoimmune or antibody-mediated diseases including but not limited to: systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, Sjogren's syndrome, autoimmune thrombocytopenia; or laboratory evidence of possible autoimmune disease determined by a positive anti-dsDNA titer, positive rheumatoid factor, proteinuria (greater than trace protein on urine dipstick testing) and/or a positive ANA.
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.

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.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

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.

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.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

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.

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.

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.

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.

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.

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.

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.

05

Study design

Phase
Phase 1
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
24 participants (actual)

Study arms

  • Experimental
    30 µg Na-GST-1 + CPG 10104

    Biological: Na-GST-1 · Biological: CPG 10104

  • Experimental
    100 µg Na-GST-1 + CPG 10104

    Biological: Na-GST-1 · Biological: CPG 10104

  • Experimental
    100 µg Na-GST-1

    Biological: Na-GST-1

Interventions

  • BiologicalNa-GST-1

    Na-GST-1/Alhydrogel®

  • BiologicalCPG 10104

    CPG 10104

06

What researchers measure

Primary outcomes

  1. Vaccine-related Adverse Events

    1. To evaluate the safety and reactogenicity of two different dose concentrations of Na-GST-1/Alhydrogel® administered with or without CPG 10104 in healthy Gabonese adults.

    Time frame: Day 380

Secondary outcomes

  1. Anti-Na-GST-1 IgG Antibody Level on Day 126

    1. To determine the dose/formulation that results in the highest level of anti-Na-GST-1 IgG antibody approximately 14 days after the final vaccination.

    Time frame: Day 126

Other outcomes

  1. Duration of antibody response to Na-GST-1

    1. To assess and compare the duration of the antibody responses to Na-GST-1 by dose and formulation.

    Time frame: Day 14, 28, 42, 56, 180, 194, 208, 270, 380

  2. IgG Subclass Distribution to Na-GST-1

    2. To assess the distribution of IgG subclass responses to Na-GST-1 by dose and formulation.

    Time frame: Day 14, 28, 42, 56, 180, 194, 208, 270, 380

07

Study locations

1 site
  • Centre de Récherches Médicales de Lambaréné
    Lambaréné, Gabon
08

References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jan 13, 2021, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03373214
Collaborators
Centre de Recherche Médicale de Lambaréné, George Washington University, Leiden University Medical Center, Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA), Amsterdam Institute for Global Health and Development
Responsible party
Maria Elena Bottazzi PhD (Professor, Baylor College of Medicine) — Principal investigator
First posted
Dec 14, 2017
Start date
Feb 1, 2018
Primary completion
Feb 28, 2019
Completion
Mar 30, 2019
Last update
Jan 13, 2021

Study contacts

Ayola Adegnika, MD
principal investigator · Centre de Recherches Medicales de Lambarené

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jan 2021. You cannot join it, but the record below documents what was studied.

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