Trial Outcomes & Findings for Development of a Skin Test for the Na-ASP-2 Hookworm Antigen (NCT NCT00603889)

Results Overview

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

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

12 participants

Primary outcome timeframe

15 minutes after skin test application

Results posted on

2012-02-23

Participant Flow

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.

Participant milestones

Participant milestones
Measure	Na-ASP-2 Hookworm Antigen Skin Test 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.
Overall Study STARTED	12
Overall Study COMPLETED	12
Overall Study NOT COMPLETED	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Development of a Skin Test for the Na-ASP-2 Hookworm Antigen

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 Participants 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.
Age, Categorical <=18 years	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	12 Participants n=5 Participants
Age, Categorical >=65 years	0 Participants n=5 Participants
Sex: Female, Male Female	8 Participants n=5 Participants
Sex: Female, Male Male	4 Participants n=5 Participants
Region of Enrollment United States	12 participants n=5 Participants

PRIMARY outcome

Timeframe: 15 minutes after skin test application

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

Outcome measures

Outcome measures
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 Participants Application of different concentrations of the Na-ASP-2 antigen skin test reagent as prick-puncture ("scratch test") and intradermal injections, applied to participants' forearms.
100 Mcg/ml Na-ASP-2 Prick-puncture Skin Test	0 Units on a scale Interval 0.0 to 0.0

SECONDARY outcome

Timeframe: 15 minutes after skin test application

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

Outcome measures

Outcome measures
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 Participants Application of different concentrations of the Na-ASP-2 antigen skin test reagent as prick-puncture ("scratch test") and intradermal injections, applied to participants' forearms.
1000 Mcg/ml Na-ASP-2 Prick-puncture Skin Test	0.21 units on a scale Interval 0.0 to 2.0

SECONDARY outcome

Timeframe: 15 minutes after skin test application

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

Outcome measures

Outcome measures
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 Participants Application of different concentrations of the Na-ASP-2 antigen skin test reagent as prick-puncture ("scratch test") and intradermal injections, applied to participants' forearms.
100 Mcg/ml Na-ASP-2 Intradermal Skin Test	0.17 units on a scale Interval 0.0 to 2.0

SECONDARY outcome

Timeframe: 15 minutes after skin test application

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

Outcome measures

Outcome measures
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 Participants Application of different concentrations of the Na-ASP-2 antigen skin test reagent as prick-puncture ("scratch test") and intradermal injections, applied to participants' forearms.
1000 Mcg/ml Na-ASP-2 Intradermal Skin Test	1.25 units on a scale Interval 0.0 to 2.0

Adverse Events

Na-ASP-2 Hookworm Antigen Skin Test

Serious events: 0 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Na-ASP-2 Hookworm Antigen Skin Test n=12 participants at risk 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.
Skin and subcutaneous tissue disorders Delayed Skin Test Reaction	16.7% 2/12 • Number of events 2

Additional Information

Dr. David Diemert, Director of Clinical Trials

Albert B. Sabin Vaccine Institute

Phone: 202-842-5025

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place