Immunogenicity of Pneumococcal Vaccines in Ataxia-telangiectasia Patients

Descriptive Immunogenicity of 2 Doses of Pneumococcal 7-valent Conjugate Vaccine (Prevenar®, Wyeth Lederle) Followed by Pneumococcal Polysaccharide Vaccine (Pneumovax® Aventis Pasteur MSD) in Ataxia-telangiectasia Patients

Ataxia-telangiectasia (AT) is a rare genetic disorder characterized by gait disorders, neuromotor dysfunction, eye abnormalities and immune deficiency. AT patients are vulnerable to cancer and infection and usually die during their 2nd or 3rd decade due to these complications. The main cause of death is respiratory infections because these patients are known to have severe type of immunodeficiency. Consequently, pneumonia is the most common infection seen in AT patients, and is usually caused by S. pneumoniae. Therefore, a routine schedule of pneumococcal vaccine is highly recommended in AT cases where immunoglobulin replacement therapy was not already initiated.

Until recently, AT patients were immunized with the pneumococcal polysaccharide vaccine (PPV23, Pneumovax® Aventis Pasteur MSD). However, data have shown that they do not respond well to these vaccines. Recently, the Israeli Ministry of Health has approved the pneumococcal 7-valent conjugate vaccine (PCV7, Prevenar®, Wyeth Lederle) for AT patients of all ages. This conjugate vaccine is known to stimulate the immune system through a different mechanism and the response is expected to be higher. The approved Israeli schedule for immunization of AT patients includes children older than 2 years that are entitled to receive 2 doses of PCV7 (8 weeks apart) boosted by PPV23, eight weeks after the second dose of PCV7. Assessment of the antibody response of such pneumococcal vaccination protocol in AT patients has never been performed.

The "Safra" Children's Hospital is the national multi-disciplinary center caring for AT patients. Approximately 50 patients from all over the country (including Jewish, Druze, Bedouin and other Muslim patients - 3 of whom are Palestinians) are followed in the clinic on a monthly basis.

Approximately 20 AT patients are not receiving IVIG replacement therapy, therefore are entitled to receive pneumococcal vaccination as stated above (mean age 10.6, 3 -23 years, 3 less than 5 years)

The aim of this study is to evaluate the responsiveness, determined by specific antibody production, of AT patients receiving this new vaccine protocol.

Study Overview

• Status: Unknown
• Conditions: Ataxia Telangiectasia
• Intervention / Treatment: Biological: Prevenar® (7-valent pneumococcal conjugate vaccine); Biological: Pneumovax® (pneumococcal polysaccharide vaccine)

Detailed Description

Ataxia-telangiectasia (AT) is a rare progressive neurodegenerative autosomal recessive disorder characterized by cerebellar ataxia, neuromotor dysfunction, oculocutaneous telangiectasia and immunodeficiency. AT patients are vulnerable to cancer and infection and usually die during their 2nd or 3rd decade due to these complications. Life expectancy does not correlate well with severity of neurological impairment. The main cause of death is respiratory infections because these patients are known to have severe type of immunodeficiency. The immunodeficiency of AT patient consists of both humoral defect (immunoglobulin deficiency and reduced response to polysaccharide antigens) and cell-mediated defect (reduced lymphocytes number and function). Consequently, pneumonia is the most common infection seen in AT patients, and is usually caused by S. pneumoniae. Therefore, a routine schedule of pneumococcal vaccine is highly recommended in AT cases where immunoglobulin replacement therapy was not already initiated.

Until recently, AT patients were immunized with the pneumococcal polysaccharide vaccine (PPV23, Pneumovax® Aventis Pasteur MSD). However, data have shown that they do not respond well to these vaccine mainly because of their reduced response to polysaccharide stimulation. Recently, the Israeli Ministry of Health has approved the pneumococcal 7-valent conjugate vaccine (PCV7, Prevenar®, Wyeth Lederle) for AT patients of all ages. In contrast to polysaccharide vaccines, this conjugate vaccine is known to stimulate the immune system through T-cell dependent mechanism, and therefore the response is expected to be higher. The approved Israeli schedule for immunization of AT patients includes children older than 2 years that are entitled to receive 2 doses of PCV7 (8 weeks apart) boosted by PPV23, eight weeks after the second dose of PCV7. Assessment of the immunogenicity of such pneumococcal vaccination protocol in AT patients has never been performed.

The "Safra" Children's Hospital is the national multi-disciplinary center caring for AT patients. Approximately 50 patients from all over the country (including Jewish, Druze, Bedouin and other Muslim patients - 3 of whom are Palestinians) are followed in the clinic on a monthly basis.

Approximately 20 AT patients are not receiving IVIG replacement therapy, therefore are entitled to receive pneumococcal vaccination as stated above (mean age 10.6, 3 -23 years, 3 less than 5 years.

The aim of this study is to evaluate the responsiveness, determined by specific antibody production, of AT patients receiving the new vaccine protocol that was recently approved to use by the Israeli Ministry of Health.

• Study Type: Observational
• Enrollment (Anticipated): 20

Contacts and Locations

• Study Contact: Name: Galia Barkai, MD; Phone Number: 972-3-530-5978; Email: Galia.Barkai@sheba.health.gov.il

Study Locations

• Israel
  • Tel Hashomer, Israel, 52621
    • Chaim Sheba Medical Center
    • Contact: Galia Barkai, MD; Phone Number: 972-3-5305978; Email: Galia.Barkai@sheba.health.gov.il
    • Principal Investigator: Galia Barkai, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 2 years to 25 years (Child, Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Ataxia Telangiectasia patients, not cuurntly on replacement Immunoglobulin G therapy

Description

Inclusion Criteria:

1. AT patients attending the national AT clinic
2. 2+ years of age
3. Agree to join this study

Exclusion Criteria:

1. Patients on regular immunoglobulin replacement therapy (other patients who are not on replacement therapy but have received IVIG 3 months or less before the beginning of the study)
2. Current infection
3. Previous serious adverse reactions to vaccination
4. Administration of other vaccines within 4 weeks before administration of study vaccine or plan for vaccination 26 weeks following the first vaccine (PCV7)

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Primary end point will be levels of antibodies against 13 serotypes of streptococcus pneumoniae following vaccination with 2 doses of PCV7 and 1 dose of PPV23. All endpoints will include both ELISA and OPA antibodies.	1 year

Collaborators and Investigators

• Sponsor: Sheba Medical Center

Study record dates

Study Major Dates

• Study Start: March 1, 2010
• Primary Completion (Anticipated): February 1, 2011
• Study Completion (Anticipated): February 1, 2011

Study Registration Dates

• First Submitted: February 24, 2010
• First Submitted That Met QC Criteria: February 24, 2010
• First Posted (Estimate): February 25, 2010

Study Record Updates

• Last Update Posted (Estimate): March 16, 2010
• Last Update Submitted That Met QC Criteria: March 15, 2010
• Last Verified: March 1, 2010

More Information

Terms related to this study

• Keywords: Pneumococcal Vaccines; ataxia telangiectasia
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Metabolic Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Immunologic Deficiency Syndromes; Immune System Diseases; Neurologic Manifestations; Genetic Diseases, Inborn; Dyskinesias; DNA Repair-Deficiency Disorders; Neurocutaneous Syndromes; Cerebellar Diseases; Primary Immunodeficiency Diseases; Spinocerebellar Ataxias; Ataxia; Telangiectasis; Cerebellar Ataxia; Ataxia Telangiectasia; Physiological Effects of Drugs; Immunologic Factors; Vaccines; Heptavalent Pneumococcal Conjugate Vaccine
• Other Study ID Numbers: SHEBA-09-7444-GB-CTIL