Polysaccharide Antibody Response Study (PARS)

Universitaire Ziekenhuizen KU Leuven

Status and phase: Completed; Phase 4

Conditions: Specific Polysaccharide Antibody Deficiency

Treatments: Biological: Typhim Vi (Sanofi Pasteur MSD); Biological: Pneumovax 23 (Sanofi Pasteur MSD)

Study type: Interventional

Funder types: Other

Identifiers

NCT02429531

S57605

Details and patient eligibility

About

Specific polysaccharide antibody deficiency (SPAD) is a primary immunodeficiency characterized by a deficient antibody production to capsular polysaccharides with normal total immunoglobulin levels. Patients suffer from recurrent ear-nose and throat infections and lung infections. SPAD can also occur as part of a primary immunodeficiency affecting other components of the immune system. Diagnosis of SPAD is hampered by difficulties with the interpretation of the Pneumovax 23 antibody response. The purpose of this study is to assess the diagnostic value of the Typhim Vi antibody response and allohemagglutinin titers as an alternative to the Pneumovax 23 response to detect polysaccharide specific antibody deficiency.

Full description

Healthy controls (n = 100) and patients with suspected SPAD (n = 100) will be immunized with both Pneumovax 23 and Typhim Vi (age 18 months - 55 years). Analyses of anti-pneumococcal polysaccharide antibodies and anti-Vi antibodies are performed before and 3-4 weeks after vaccination. Also bloodgroup and anti-A/anti-B are assessed. Relevant clinical information (ENT infections, lung infections, bronchiectasis, invasive infections) is obtained from the patient file and history and is noted in a Case Report Form.

The diagnostic performance of Typhim Vi response and allohemagglutinins will be analyzed by calculating sensitivity, specificity, predictive values, likelihood ratios and Receiver Operating Characteristic curves for Typhim Vi and allohemagglutinins using pneumococcal antibody response as the reference standard. The association between low Typhim Vi response or low allohemagglutinins and clinical signs of polysaccharide antibody deficiency will be studied by multiple logistic regression.

Enrollment: 200 patients

Sex: All

Ages: 18 months to 55 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Assessment of polysaccharide antibody response is indicated for the clinical care of the patient (not for healthy volunteers)
• Informed consent given

Exclusion criteria

• History of serious adverse reaction to a vaccine
• Vaccination with Typhim Vi or Pneumovax 23 in 5 years prior to the study
• (Potential) pregnancy

Trial design

Primary purpose: Diagnostic

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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200 participants in 2 patient groups

Healthy controls

Experimental group

Description:

Healthy volunteers who consented to participate in the study will be immunized with both Pneumovax 23 and Typhim Vi .

Treatment:

Biological: Pneumovax 23 (Sanofi Pasteur MSD)

Biological: Typhim Vi (Sanofi Pasteur MSD)

Patients

Experimental group

Description:

Patients presenting for immune evaluation because of recurrent ENT/lung infection or invasive infection with encapsulated bacteria, in whom evaluation of pneumococcal antibody response is indicated, will be immunized with both Pneumovax 23 and Typhim Vi .

Treatment:

Biological: Pneumovax 23 (Sanofi Pasteur MSD)

Biological: Typhim Vi (Sanofi Pasteur MSD)