An interventional study of Na-ASP-2 Skin Test Reagent in Hookworm Infection and Allergy, sponsored by Albert B. Sabin Vaccine Institute. Completed at 1 site in United States. Open to participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2012-02-23.
Sponsored by Albert B. Sabin Vaccine Institute · Not applicable, Interventional, and Diagnostic
Na-ASP-2 is a protein expressed during the larval stage of the N. americanus hookworm life cycle. In a clinical study in previously hookworm-infected adults in Brazil, this protein induced urticarial reactions (rash) in a subset of volunteers. This study will evaluate solutions of varying concentrations of the protein in both a skin prick-puncture and intradermal test that will eventually be used to screen volunteers living in hookworm endemic areas who are being considered as potential participants in vaccine trials, to reduce the potential of inducing allergic reactions in those vaccinated with the Na-ASP-2 Hookworm Vaccine.
Each participant will have both skin prick-puncture and intradermal skin tests applied on the same study day. The prick-puncture and intradermal tests will be applied sequentially to the volar aspects of the participant's forearms:
39 studies on the registry are indexed under Hookworm Infections; 5 are open to participants now.
This study's enrollment of 12 is below the median of 182 across 36 interventional studies indexed under Hookworm Infections.
Browse Hookworm Infections studies →Albert B. Sabin Vaccine Institute is the lead sponsor of 11 studies on the registry; 1 is open to participants now.
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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.
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Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
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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.
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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.
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.
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.
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.
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.
All participants will have the same number of concentrations of the Na-ASP-2 skin test reagent applied to their arms, using both the prick-puncture and intradermal techniques.
Biological: Na-ASP-2 Skin Test Reagent
Na-ASP-2 Hookworm Skin Test Reagent, 1-1000 mcg/mL solution
100 Mcg/ml Na-ASP-2 Prick-puncture Skin Test
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
Time frame: 15 minutes after skin test application
1000 Mcg/ml Na-ASP-2 Prick-puncture Skin Test
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
Time frame: 15 minutes after skin test application
100 Mcg/ml Na-ASP-2 Intradermal Skin Test
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
Time frame: 15 minutes after skin test application
1000 Mcg/ml Na-ASP-2 Intradermal Skin Test
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
Time frame: 15 minutes after skin test application
Recruitment occurred between March and May 2008, primarily by means of advertising the study in and around The George Washington University, where the study site is located.
| Milestone | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| Started | 12 |
| Completed | 12 |
| Not completed | 0 |
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
| Units on a scale | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| 100 Mcg/ml Na-ASP-2 Prick-puncture Skin Test | 0 (0 to 0) |
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
| units on a scale | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| 1000 Mcg/ml Na-ASP-2 Prick-puncture Skin Test | 0.21 (0 to 2) |
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
| units on a scale | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| 100 Mcg/ml Na-ASP-2 Intradermal Skin Test | 0.17 (0 to 2) |
Mean grade of wheal reaction after 2 applications of the skin test reagent per participant. For each skin test reaction, the grade of the test was determined based on the mean of the longest and orthogonal diameters, which was then compared to the equivalent measurements of a histamine solution positive control that was applied at the same time as the test. Grading was as follows: 0 no discernible wheal 1. \< ½ histamine diameter 2. ≥ ½ histamine; \< histamine diameter 3. = size of histamine control ± 1 mm 4. \> histamine diameter; \< 2x diameter 5. ≥ 2x histamine control
| units on a scale | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| 1000 Mcg/ml Na-ASP-2 Intradermal Skin Test | 1.25 (0 to 2) |
Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Na-ASP-2 Hookworm Antigen Skin Test | — | 0/12 (0%) | 2/12 (16.7%) |
| Event | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| Delayed Skin Test ReactionSkin and subcutaneous tissue disorders | 2/12 |
| Age, Categorical(Participants) | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 12 |
| >=65 years | 0 |
| Sex: Female, Male(Participants) | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| Female | 8 |
| Male | 4 |
| Region of Enrollment(participants) | Na-ASP-2 Hookworm Antigen Skin Test |
|---|---|
| United States | 12 |
The record gives a start of Mar 2008, a primary completion of May 2008 and a completion of May 2008. It does not say whether these dates are actual or estimated.
Results were first posted in Feb 2012, 3 years 9 months after primary completion.
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This study is completed, as verified in Jan 2012. You cannot join it, but the record below documents what was studied.
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Albert B. Sabin Vaccine Institute