A Phase 2 interventional study of Na-GST-1/Alhydrogel and Na-GST-1/Alhydrogel + CPG 10104 in Hookworm Infections, 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 2026-03-12.
Sponsored by Baylor College of Medicine · Phase 2, Interventional, and Prevention
This study evaluates the efficacy, safety and immunogenicity of different formulations of the Na-GST-1 hookworm vaccine using a controlled human hookworm infection model in healthy, hookworm-naive adults.
Double blind, randomized, controlled, Phase 2 clinical trial in hookworm-unexposed adults living in the metropolitan area of Washington, DC. Subjects will receive three doses of the assigned vaccine formulation, or saline placebo, delivered intramuscularly on approximately Days 0, 56, and 112.
Subjects will be challenged with 50 infectious N. americanus larvae 4 weeks after 3rd vaccination. Fecal samples will be collected weekly starting 4 weeks post-challenge. Albendazole will be administered 20 weeks post-challenge to cure infections. Subjects will be followed until 10 months after their final vaccination.
Safety of vaccination 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. Safety of CHHI will be measure from the time of larval application (Day 140) through the first day of treatment with albendazole (Day 280).
Unsolicited non-serious adverse events (AEs) will be collected until approximately 1 month following each study vaccination and from study Day 140 (day of CHHI) through Day 280.
New-onset chronic medical conditions and Serious Adverse Events (SAEs) will be collected from the time of the first study vaccination through approximately 10 months after the third study vaccination (final visit). Clinical laboratory evaluations for safety will be performed on venous blood collected approximately 14 days after each vaccination and CHHI.
Immunogenicity testing will include IgG antibody responses to Na-GST-1, by a qualified indirect enzyme-linked immunosorbent assay (ELISA), on serum obtained prior to each study vaccination and CHHI, and at time points after each vaccination and after CHHI (see Appendix A); the affinity of vaccine-induced antibodies against Na-GST-1 using Surface Plasmon Resonance; the functional activity of vaccine-induced antibodies via in vitro enzyme neutralization assay; antigen-specific memory B cell responses; and, the innate immune responses to each of the TLR receptor immunostimulants.
Parasitological testing will include microscopic fecal egg detection by a qualified saline flotation technique, fecal egg counts by the McMaster method, fecal PCR for hookworm DNA, and peripheral eosinophil counts.
Recruitment and enrollment into the study will occur on an ongoing basis, with each group being recruited and vaccinated in sequence.
48 subjects will be enrolled into 4 groups of 12. Subjects will be enrolled sequentially and upon enrollment will be randomized to one of the following IP assignments in a double-blind fashion:
39 studies on the registry are indexed under Hookworm Infections; 5 are open to participants now.
This study's enrollment of 39 is below the median of 182 across 36 interventional studies indexed under Hookworm Infections.
Browse Hookworm Infections studies →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.
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.
Exclusion Criteria:
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.
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.
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.
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).
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.
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.
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.
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.
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.
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).
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.
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 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.
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 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.
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
100 µg Na-GST-1/Alhydrogel administered intramuscularly in the deltoid on study days 0, 56 and 112 followed by controlled human hookworm infection with 50 infectious Necator americanus larvae on study day 140.
Biological: Na-GST-1/Alhydrogel · Drug: Albendazole · Other: Necator americanus Larval Inoculum
100 µg Na-GST-1/Alhydrogel co-administered with 500 µg CPG 10104 delivered intramuscularly in the deltoid on study days 0, 56 and 112 followed by controlled human hookworm infection with 50 infectious Necator americanus larvae on study day 140.
Biological: Na-GST-1/Alhydrogel + CPG 10104 · Drug: Albendazole · Other: Necator americanus Larval Inoculum
100 µg Na-GST-1/Alhydrogel co-administered with 5 µg GLA-AF delivered intramuscularly in the deltoid on study days 0, 56 and 112 followed by controlled human hookworm infection with 50 infectious Necator americanus larvae on study day 140.
Biological: Na-GST-1/Alhydrogel + GLA-AF · Drug: Albendazole · Other: Necator americanus Larval Inoculum
Sterile saline placebo delivered intramuscularly in the deltoid on study days 0, 56 and 112 followed by controlled human hookworm infection with 50 infectious Necator americanus larvae on study day 140.
Biological: Placebo · Drug: Albendazole · Other: Necator americanus Larval Inoculum
Recombinant Necator americanus Glutathione-S Transferase adjuvanted with Alhydrogel
Also known as: Necator americanus Glutathione-S Transferase
Recombinant Necator americanus Glutathione-S Transferase adjuvanted with Alhydrogel and co-administered with CPG 10104, a synthetic oligodeoxynucleotide
Recombinant Necator americanus Glutathione-S Transferase adjuvanted with Alhydrogel and co-administered with an aqueous formulation of Glucopyranosyl-Lipid A (GLA-AF)
Physiological sterile saline solution
Treatment with 3 daily oral doses of 400 mg albendazole at end of study.
50 infectious Necator americanus larvae applied via dermal application (challenge infection).
Detectable Hookworm Infection
Proportion of subjects with detectable hookworm eggs, at any time point, in fecal samples, as determined by microscopy using the qualified saline flotation technique
Time frame: On Study Days 175, 182, 189, 203, 217, 231, 245, 259, 273, and 280.
Incidence of Serious Adverse Events
Frequency of study vaccine-related Serious Adverse Events from the time of the first study vaccination through approximately 10 months after the last study vaccination.
Time frame: Beginning on Day 0 when the first dose is received and ending on Day 380 (final study visit).
Incidence of Solicited Injection Site and Systemic Reactogenicity
Frequency of solicited injection site and systemic reactogenicity, graded by severity, on the day of each study vaccination through 14 days after each study vaccination.
Time frame: Dose 1: Days 0, 3, 7, 14; Dose 2: Days 56, 59, 63, 70; Dose 3: Days 112, 115, 119, 126
Incidence of Solicited Adverse Events
Frequency of solicited adverse events, graded by severity, on the day of CHHI through study Day 280
Time frame: Day of CHHI, Day 140, and study days: 143, 147, 154, 175, 182, 189, 196, 203, 210, 217, 224, 231, 238, 245, 252, 259, 266, 273, 280. Day 280 is the day of anti-worm treatment.
Incidence of Clinical Safety Laboratory Abnormalities
Frequency of clinical safety laboratory adverse events.
Time frame: Study days: 0, 14, 56, 70, 112, 126, 140, 154, 175, 189, 203, 217, 231, 259, 280.
Incidence of Unsolicited Adverse Events
Frequency of unsolicited adverse events, graded by severity, from the time of each study vaccination through approximately 1 month after each study vaccination; and from the time of CHHI through treatment with albendazole (Day 280)
Time frame: From Dose 1 on Day 0 until anti-worm treatment on Day 280.
Incidence of New-onset Chronic Medical Conditions
Frequency of new-onset chronic medical conditions through approximately 10 months after the third study vaccination.
Time frame: Entire duration of the study. Beginning Day 0, day of first dose, until Day 380, final study visit.
Incidence of Adverse Events of Special Interest
Frequency of Adverse Events of Special Interest through approximately 10 months after the third study vaccination.
Time frame: Entire duration of the study. Beginning Day 0, day of first dose, until Day 380, final study visit.
Fecal Egg Counts
Fecal egg counts as determined by microscopy using the McMaster method, weekly from Weeks 5 through 20 post-CHHI
Time frame: Week 5 and Week 20 post-CHHI. Study days: 175, 182, 189, 203, 217, 231, 245, 259, 273, and 280.
Anti-Na-GST-1 IgG Antibody Response
Anti-Na-GST-1 IgG antibody response as measured in Arbitrary Units per milliliter (AU/mL) of serum, determined by a qualified indirect enzyme-linked immunosorbent assay (ELISA) at approximately 14 days after each vaccination, and approximately 1, 2, 4, 6, 7, 8 and 10 months after the third dose. Levels of IgG antibodies against Na-GST-1 were converted to AUs by homologous interpolation of Optical Density readings at 492nm (OD492) from a standard calibration curve derived from serial dilutions of a human standard reference serum pool collected from high IgG responders (OD492 ≥ 1.000).
Time frame: Study days: 14, 70, 126, 140, 175, 189, 231, 280, 320, and 380
Recruitment and enrollment occurred on an ongoing basis, with each group being recruited and vaccinated in parallel. Participants were enrolled sequentially and upon enrollment were randomized to one of the four groups.
| Milestone | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Started | 10 | 9 | 10 | 10 |
| Completed | 9 | 5 | 10 | 8 |
| Not completed | 1 | 4 | 0 | 2 |
Proportion of subjects with detectable hookworm eggs, at any time point, in fecal samples, as determined by microscopy using the qualified saline flotation technique
| Participants | Group 1: Na-GST-1/Alhydrogel | Group 2: Na-GST-1/Alhydrogel + CPG 10104 | Group 3: Na-GST-1/Alhydrogel + GLA-AF | Group 4: Saline Placebo |
|---|---|---|---|---|
| Day 175 | 0 | 0 | 0 | 0 |
| Day 182 | 0 | 0 | 0 | 1 |
| Day 189 | 0 | 0 | 0 | 2 |
| Day 203 | 4 | 1 | 3 | 2 |
| Day 217 | 3 | 1 | 4 | 4 |
| Day 231 | 4 | 1 | 6 | 4 |
| Day 245 | 3 | 0 | 5 | 3 |
| Day 259 | 2 | 0 | 4 | 4 |
| Day 273 | 2 | 0 | 6 | 3 |
| Day 280 | 3 | 0 | 5 | 3 |
Frequency of study vaccine-related Serious Adverse Events from the time of the first study vaccination through approximately 10 months after the last study vaccination.
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Incidence of Serious Adverse Events | 0 | 0 | 0 | 0 |
Frequency of solicited injection site and systemic reactogenicity, graded by severity, on the day of each study vaccination through 14 days after each study vaccination.
| Participants | Group 1: Na-GST-1/Alhydrogel | Group 2: Na-GST-1/Alhydrogel + CPG 10104 | Group 3: Na-GST-1/Alhydrogel + GLA-AF | Group 4: Saline Placebo |
|---|---|---|---|---|
| Number of Participants Reporting Solicited Adverse Events Post Dose #1 | 10 | 9 | 10 | 7 |
| Number of Participants Reporting Solicited Adverse Events Post Dose #2 | 9 | 7 | 9 | 5 |
| Number of Participants Reporting Solicited Adverse Events Post Dose #3 | 8 | 7 | 9 | 7 |
Frequency of solicited adverse events, graded by severity, on the day of CHHI through study Day 280
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Incidence of Solicited Adverse Events | 8 | 5 | 10 | 9 |
Frequency of clinical safety laboratory adverse events.
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Number of Participants reporting Clinical Laboratory Adverse Event during Vaccination Phase | 1 | 3 | 0 | 2 |
| Number of Participants reporting Clinical Laboratory Adverse Event during CHHI Phase | 7 | 3 | 9 | 7 |
Frequency of unsolicited adverse events, graded by severity, from the time of each study vaccination through approximately 1 month after each study vaccination; and from the time of CHHI through treatment with albendazole (Day 280)
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Participants Reporting Unsolicited AEs up to 28 Days After Dose #1 | 5 | 6 | 4 | 8 |
| Participants Reporting Unsolicited AEs up to 28 Days After Dose #2 | 3 | 5 | 6 | 6 |
| Participants Reporting Unsolicited AEs up to 28 Days After Dose #3 | 6 | 4 | 5 | 7 |
| Participants Reporting Unsolicited AEs post-CHHI | 9 | 5 | 10 | 9 |
Frequency of new-onset chronic medical conditions through approximately 10 months after the third study vaccination.
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Incidence of New-onset Chronic Medical Conditions | 0 | 0 | 0 | 0 |
Frequency of Adverse Events of Special Interest through approximately 10 months after the third study vaccination.
| Participants | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Incidence of Adverse Events of Special Interest | 0 | 0 | 0 | 0 |
Fecal egg counts as determined by microscopy using the McMaster method, weekly from Weeks 5 through 20 post-CHHI
| Eggs | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Week 5 post-CHHI (Day 175) | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.0 ± 0.0 |
| Week 6 post-CHHI (Day 182) | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.0 ± 0.0 | 4.2 ± 11.8 |
| Week 7 post-CHHI (Day 189) | 0.0 ± 0.0 | 0.0 ± 0.0 | 0.0 ± 0.0 | 10.4 ± 23.5 |
| Week 9 post-CHHI (Day 203) | 11.1 ± 16.7 | 0.0 ± 0.0 | 5.6 ± 11.8 | 31.0 ± 58.1 |
| Week 10 post-CHHI (Day 217) | 7.4 ± 12.1 | 0.0 ± 0.0 | 22.9 ± 41.7 | 38.9 ± 62.9 |
| Week 12 post-CHHI (Day 231) | 14.8 ± 19.4 | 0.0 ± 0.0 | 48.3 ± 88.7 | 29.6 ± 58.8 |
| Week 14 post-CHHI (Day 245) | 16.7 ± 34.5 | 0.0 ± 0.0 | 35.0 ± 50.0 | 14.6 ± 30.1 |
| Week 16 post-CHHI (Day 259) | 31.5 ± 72.9 | 0.0 ± 0.0 | 59.3 ± 89.8 | 31.0 ± 29.5 |
| Week 18 post-CHHI (Day 273) | 16.7 ± 35.6 | 0.0 ± 0.0 | 33.3 ± 43.7 | 38.1 ± 48.8 |
| Week 20 post-CHHI (Day 280) | 13.0 ± 23.2 | 0.0 ± 0.0 | 35.4 ± 52.3 | 16.7 ± 23.6 |
Anti-Na-GST-1 IgG antibody response as measured in Arbitrary Units per milliliter (AU/mL) of serum, determined by a qualified indirect enzyme-linked immunosorbent assay (ELISA) at approximately 14 days after each vaccination, and approximately 1, 2, 4, 6, 7, 8 and 10 months after the third dose. Levels of IgG antibodies against Na-GST-1 were converted to AUs by homologous interpolation of Optical Density readings at 492nm (OD492) from a standard calibration curve derived from serial dilutions of a human standard reference serum pool collected from high IgG responders (OD492 ≥ 1.000).
| Arbitrary Units (AUs) per milliliter | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Day 14 | 1.7 ± 0.9 | 1.4 ± 0.0 | 1.4 ± 0.0 | 1.7 ± 1.0 |
| Day 70 (14 days post Dose 2) | 5.6 ± 1.1 | 34.8 ± 30.9 | 26.7 ± 65.5 | 2.0 ± 1.8 |
| Day 126 (14 days post Dose 3) | 21.1 ± 32.4 | 55.3 ± 65.4 | 18.7 ± 23.3 | 1.4 ± 0.0 |
| Day 140 (1 month post Dose 3) | 8.5 ± 5.1 | 31.0 ± 29.5 | 10.9 ± 12.7 | 2.2 ± 2.3 |
| Day 175 (2 months post Dose 3) | 6.9 ± 5.2 | 42.6 ± 72.1 | 7.7 ± 7.9 | 1.7 ± 1.0 |
| Day 189 (4 months post Dose 3) | 7.1 ± 5.8 | 26.3 ± 28.4 | 6.2 ± 6.6 | 2.2 ± 2.3 |
| Day 231 (6 months post Dose 3) | 6.3 ± 4.4 | 35.1 ± 53.3 | 5.2 ± 5.8 | 2.3 ± 2.6 |
| Day 280 (7 months post Dose 3) | 4.5 ± 2.9 | 21.6 ± 26.7 | 4.0 ± 3.8 | 2.4 ± 2.6 |
| Day 320 (8 months post Dose 3) | 4.6 ± 3.0 | 22.8 ± 35.8 | 3.8 ± 3.1 | 2.6 ± 3.3 |
| Day 380 (10 months post Dose 3) | 3.9 ± 3.4 | 110 ± 11.6 | 3.1 ± 3.4 | 2.3 ± 2.3 |
Collected over For the Vaccination phase, solicited AEs were collected from the day of study vaccination through 14 days after each study vaccination and unsolicited AEs were collected from the day of study vaccination through 28 days after each vaccination. For the CHHI phase, solicited adverse events were collected from day of hookworm larvae administration (day 140) through day 280, the day albendazole treatment and unsolicited AEs were collected from day 140 through day 297.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Na-GST-1/Alhydrogel | 0/10 (0%) | 0/10 (0%) | 10/10 (100%) |
| Na-GST-1/Alhydrogel + CPG 10104 | 0/9 (0%) | 1/9 (11.1%) | 9/9 (100%) |
| Na-GST-1/Alhydrogel + GLA-AF | 0/10 (0%) | 0/10 (0%) | 10/10 (100%) |
| Saline Placebo | 0/10 (0%) | 0/10 (0%) | 10/10 (100%) |
| Event | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| HospitalizationGeneral disorders | 0/10 | 1/9 | 0/10 | 0/10 |
| Event | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo |
|---|---|---|---|---|
| Eosinophil Count IncreasedInvestigations | 8/9 | 2/5 | 10/10 | 8/9 |
| Injection Site PainGeneral disorders | 10/10 | 7/9 | 8/10 | 6/10 |
| Injection Site TendernessGeneral disorders | 10/10 | 8/9 | 10/10 | 6/10 |
| Application Site PruritusGeneral disorders | 5/9 | 5/5 | 5/10 | 4/9 |
| Application Site DiscolourationGeneral disorders | 8/9 | 0/5 | 7/10 | 6/9 |
| HeadacheNervous system disorders | 4/10 | 8/9 | 2/10 | 8/10 |
| Application Site RashGeneral disorders | 7/9 | 2/5 | 4/10 | 4/9 |
| FlatulenceGastrointestinal disorders | 5/9 | 1/5 | 7/10 | 6/9 |
| FlatulenceGastrointestinal disorders | 6/9 | 0/5 | 6/10 | 1/9 |
| HeadacheNervous system disorders | 2/9 | 0/5 | 6/10 | 6/9 |
| Age, Continuous(Years) | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo | Total |
|---|---|---|---|---|---|
| Mean | 26.1 ± 4.6 | 30.4 ± 8.2 | 24.7 ± 3.3 | 26.1 ± 3.45 | 26.7 ± 5.4 |
| Age, Customized(Years) | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo | Total |
|---|---|---|---|---|---|
| Age, Continuous | 25.5 (19.0 to 34.0) | 29.0 (21.0 to 44.0) | 23.5 (21.0 to 30.0) | 25.5 (22.0 to 31.0) | 26.0 (19.0 to 44.0) |
| Sex: Female, Male(Participants) | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo | Total |
|---|---|---|---|---|---|
| Female | 4 | 5 | 6 | 7 | 22 |
| Male | 6 | 4 | 4 | 3 | 17 |
| Race/Ethnicity, Customized(Participants) | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo | Total |
|---|---|---|---|---|---|
| Race — American Indian or Alaska Native | 0 | 1 | 0 | 0 | 1 |
| Race — Asian | 0 | 0 | 4 | 1 | 5 |
| Race — Black or African American | 1 | 1 | 0 | 1 | 3 |
| Race — Other | 1 | 2 | 0 | 2 | 5 |
| Race — White | 8 | 5 | 6 | 6 | 25 |
| Race/Ethnicity, Customized(Participants) | Na-GST-1/Alhydrogel | Na-GST-1/Alhydrogel + CPG 10104 | Na-GST-1/Alhydrogel + GLA-AF | Saline Placebo | Total |
|---|---|---|---|---|---|
| Ethnicity — Hispanic or Latino | 1 | 3 | 1 | 2 | 7 |
| Ethnicity — Not Hispanic or Latino | 9 | 6 | 9 | 8 | 32 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — GW provided agreement with that NIAID that it will make publicly available all final research data resulting from this U01 clinical trial, in a timely fashion following closure of the clinical trial (not more than 12 months after the last subject follow-up visit). At no time will subject identifying information be made publically available.
Supporting information: Study protocol, Informed consent form, Clinical study report
Time frame: Within 12 months of final study visit.
Access criteria: To be determined.
Ran from Mar 2018 to primary completion in Dec 2024, 81 months.
Results were first posted in Dec 2025, 11 months after primary completion.
How these figures are worked out, and which studies are left out of them.
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