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

NCT00603889 | Completed Results

• 1 other identifier: SVI-07-02
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Hookworm Infection; Allergy

Keywords

Hookworm; Allergy; Vaccine; Skin test

Outcome Measures

Primary Outcomes (1)

• 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

  15 minutes after skin test application

Secondary Outcomes (3)

• 1000 Mcg/ml Na-ASP-2 Prick-puncture Skin Test

  15 minutes after skin test application

• 100 Mcg/ml Na-ASP-2 Intradermal Skin Test

  15 minutes after skin test application

• 1000 Mcg/ml Na-ASP-2 Intradermal Skin Test

  15 minutes after skin test application

Study Arms (1)

Na-ASP-2 Hookworm Antigen Skin Test

EXPERIMENTAL

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

Interventions

Na-ASP-2 Skin Test Reagent BIOLOGICAL

Na-ASP-2 Hookworm Skin Test Reagent, 1-1000 mcg/mL solution

Na-ASP-2 Hookworm Antigen Skin Test

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Males or females between 18 and 45 years of age, inclusive.
• Good general health as determined by means of the screening procedure.
• Willingness to participate in the study as evidenced by signing the informed consent document.

You may not qualify if:

• History of previous infection with hookworm.
• Prior extensive and continuous travel, work, or residence (\> 1 month) in a hookworm-endemic region.
• Pregnancy as determined by a positive urine hCG test (if female).
• Evidence of clinically significant neurologic, cardiac, pulmonary, hepatic, rheumatologic, autoimmune, or renal disease by history or physical examination.
• Behavioral, cognitive, or psychiatric disease that in the opinion of the investigator affects the ability of the volunteer to understand and cooperate with the study protocol.
• Other condition that in the opinion of the investigator would jeopardize the safety or rights of a volunteer participating in the trial or would render the subject unable to comply with the protocol.
• Participation in an investigational vaccine or drug trial within 14 days of starting this study.
• Volunteer has had medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 12 months.
• History of a severe allergic reaction or anaphylaxis.
• Known immunodeficiency syndrome.
• Use of corticosteroids (excluding topical or nasal) or immunosuppressive drugs within 30 days of starting this study.
• History of a surgical splenectomy.
• Extensive dermatitis precluding skin testing
• Current use of a beta blocker (oral or topical) or anti-histamine medication. A volunteer may participate in the study if they agree to withhold use of an anti-histamine for at least 5 days prior to application of the skin test.
• Use of a tricyclic anti-depressant within the past month.

Sponsors & Collaborators

• Albert B. Sabin Vaccine Institute: lead

Study Sites (1)

GWUMC Clinical Trials Unit

Washington D.C., District of Columbia, 20037, United States

Location

Related Publications (3)

• Fujiwara RT, Bethony J, Bueno LL, Wang Y, Ahn SY, Samuel A, Bottazzi ME, Hotez P, Mendez S. Immunogenicity of the hookworm Na-ASP-2 vaccine candidate: characterization of humoral and cellular responses after vaccination in the Sprague Dawley rat. Hum Vaccin. 2005 May-Jun;1(3):123-8. doi: 10.4161/hv.1.3.1924. Epub 2005 May 20.

  PMID: 17012856 BACKGROUND

• Goud GN, Bottazzi ME, Zhan B, Mendez S, Deumic V, Plieskatt J, Liu S, Wang Y, Bueno L, Fujiwara R, Samuel A, Ahn SY, Solanki M, Asojo OA, Wang J, Bethony JM, Loukas A, Roy M, Hotez PJ. Expression of the Necator americanus hookworm larval antigen Na-ASP-2 in Pichia pastoris and purification of the recombinant protein for use in human clinical trials. Vaccine. 2005 Sep 15;23(39):4754-64. doi: 10.1016/j.vaccine.2005.04.040.

  PMID: 16054275 BACKGROUND

• Diemert DJ, Bethony JM, Hotez PJ. Hookworm vaccines. Clin Infect Dis. 2008 Jan 15;46(2):282-8. doi: 10.1086/524070.

  PMID: 18171264 BACKGROUND

MeSH Terms

Conditions

Hookworm Infections; Hypersensitivity; Ancylostomiasis

Condition Hierarchy (Ancestors)

Strongylida Infections; Secernentea Infections; Nematode Infections; Helminthiasis; Parasitic Diseases; Infections; Immune System Diseases

Results Point of Contact

• Title: Dr. David Diemert, Director of Clinical Trials
• Organization: Albert B. Sabin Vaccine Institute

david.diemert@sabin.org

202-842-5025

Study Officials

• David Parenti, MD

  GWUMC Medical Faculty Associates

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 17, 2008
• First Posted: January 29, 2008
• Study Start: March 1, 2008
• Primary Completion: May 1, 2008
• Study Completion: May 1, 2008
• Last Updated: February 23, 2012
• Results First Posted: February 23, 2012

Record last verified: 2012-01

Locations

US (1)