Antibodies and Memory Cells Role After Different Pneumococcal Vaccines in HIV Adults

January 9, 2017 updated by: Francesca Montagnani, University of Siena

Long Term Serological Response and Memory Cells Role After Different Pneumococcal Vaccine Strategies in HIV Adults

Streptococcus pneumoniae is a cause of high morbidity and mortality in HIV-positive subjects, representing the leading etiological agent of severe bacterial pneumonia. International guidelines recommend that HIV positive patients aged >=19 years, who are 13-valent conjugate vaccine (PCV13) naïve, should receive a single dose of PCV13. Pneumococcal polysaccharide vaccine 23-valent (PPV23) should be given >=8 weeks after indicated dose of PCV13, and a second dose of PPV23 should be given 5 years later. For those who previously received PPV23, PCV13 should be administered >=1 year after the last PPV23 dose. HIV infection affects humoral immunity both through reduced T-cell help and changes in the B-cell compartment. Neither amount of circulating memory B cells nor their functions are restored by antiretroviral therapy: this may affect antibody mediated immunity, even in well-treated HIV patients. In asplenic childrens a single dose of PCV13 seems sufficient to restore the pool of anti-pneumococcal polysaccharides IgG memory B cells. In adults, it has been reported that a single dose of 7-valent pneumococcal conjugate vaccine induces significant increases in serotype-specific memory B-cell populations, conversely, immunization with PPV23 seems to decrease memory B-cell frequency. However, data on immunological response after PCV13 in HIV positive adults are still scanty and the optimal pneumococcal prophylaxis strategy needs further investigation. Number of PCV13 doses is actually demanded to clinical judgment for each patient; also current Italian indications recommend at least one dose, but till 3 doses seem to be suggested for immunocompromised patients. Present study aims to investigate short and long term immunological response after different standard vaccine schedule and to evaluate pneumococcal nasopharyngeal colonization in vaccinated patients.

Study Overview

Detailed Description

The study will be divided in 3 main aims; in the first, the long term immunological response to PCV13 and PPV23 in HIV+ adults will be evaluated. In a previous clinical trial (PRIN 2009 study, Clinicaltrials: NCT02123433) a cohort of HIV positive adults had been vaccinated either with 2 doses of PCV13 8 weeks apart or 1 dose of PPV23 (last enrollment: December 2012). Immunoglobulins G (IgGs) against 12 common pneumococcal serotypes included in PCV13 and PPV23 were quantified by ELISA at baseline (BL), 8, 24 and 48 weeks: analysis are still ongoing; preliminary data revealed that both vaccines were safe and well tolerated and showed similar immunogenicity. The present study aims to evaluate persistence of long term (>= 3 years) serological and memory B cells response in those previous vaccinated groups. In this phase, population will be screened for inclusion and exclusion criteria to entire study conduction. Once obtained informed consent, patients will be enrolled. Together with the collection of blood samples for routine purposes, an additional blood sample will be taken so to run immunological tests (ELISA, ELISpot). It is important to underline that no invasive procedures are needed for the study, apart from routine clinical practice: blood specimens will be obtained as part of routine investigations, blood will be hence taken for CD4+ cell count, viraemia analysis and anti-HIV drug monitoring; enrolled patients will agree just to donate a blood sample for research purposes. Blood samples will be collected from all previously PCV13 or PPV23 vaccinated HIV+ subjects and serum antibodies and B cells isotypes will be analyzed at baseline (BL), that is >= 3 years after a previous PCV13 or PPV23 vaccination.

The second objective of this study aims to evaluate short and long term immunological response with different combined vaccine strategies in HIV+ adults. Participants will be recruited if they'll have needed to receive antipneumococcal vaccines (primary or booster) according to clinical standard indications.

Elicited immunological response (serum antibodies and B cells isotypes) will be explored at BL, 8, 24, 48 and 96 weeks after additional different received pneumococcal vaccine strategies. At BL, after collecting blood samples as previously described for Aim1, every patient will be assigned to a specific Group on the basis of the received vaccine schedule, prescribed by clinicians according to individual clinical indications. Short- (30 minutes), medium- (<=5 days) and long-term adverse reactions will be reported, by clinical evaluation within 30 minute post-vaccine, phone call at day 5 and anamnestic data collection during follow up 8, 24, 48 and 96 weeks.

Blood samples will be analyzed at 8, 24, 48 and 96 weeks to evaluate serum antibodies and B cells isotypes.

Finally, the third aim of the study will lead an epidemiological and microbiological survey in vaccinated HIV+ adults. At BL, 8, 24, 48 and 96 weeks all clinical-anamnestic data will be updated, together with blood sample analysis to title IgG towards each vaccinal pneumococcal polysaccharides and to evaluate B cells isotypes and nasopharyngeal swab for S. pneumoniae culture, in vitro chemosusceptibility tests, serotyping, clonal analysis by Multilocus Locus Sequence Typing (MLST).

Carriage will be defined as S. pneumoniae isolation from one or more of the nasal swabs, in absence of any clinical signs or symptoms; a 12 months clinical follow up will be performed in colonized patients. All patients developing infections will be followed until resolution.

Study Type

Observational

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Siena, Italy, 53100
        • UOC Malattie Infettive Universitarie c/o Policlinico Le Scotte, Viale Mario Bracci 16
    • Rome
      • Roma, Rome, Italy, 00168
        • Istituto di Clinica delle Malattie Infettive c/o Policlinico Gemelli, Largo Agostino Gemelli 12

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

HIV-positive adults that undergo the International and Italian Ministry of Health indications for administration of pneumococcal vaccines.

Description

Inclusion Criteria:

  • age between 18 and 65 years
  • acceptance of informed consensus
  • HIV positivity
  • access to structures in ambulatory or Day Hospital regimen
  • CD4+ cell count > or < than 200 cells/ul
  • subjects for which Italian Ministry of Health recommend pneumococcal vaccination with PCV13 or PPV23

Exclusion Criteria:

  • pregnancy
  • acute infectious disease ongoing
  • antibiotic therapy ongoing in the previous 7 days
  • HIV-independent immunodepression
  • chronic steroid therapy
  • anatomic or functional asplenia
  • contraindication to vaccination based on package insert drug facts, such as hypersensitivity to the active ingredient or one of the bulking agents (PPV23, Pneumovax);hypersensitivity to the active ingredient, to one of the bulking agents or to the diphteria toxoid (PCV13, Prevenar 13)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Group 1
Immunological and microbiological status of HIV- positive adults with pneumococcal vaccinal status of 2 PCV13 doses received from more than 3 years that have prescription for a single booster dose of PCV13.
Study of short and long term immunological response after different schedule of PCV13 or PPV23
Evaluation of pneumococcal nasopharyngeal colonization
Group 2
Immunological and microbiological status of HIV- positive adults with pneumococcal vaccinal status of 1 PPV23 dose received from more than 3 years that have prescription to receive 2 doses (priming + boost) of PCV13.
Study of short and long term immunological response after different schedule of PCV13 or PPV23
Evaluation of pneumococcal nasopharyngeal colonization
Group 3
HIV- positive adults that have never received a pneumococcal vaccine (naive) and have a CD4+ cell count < 200 cells/ul that have prescription to be primed with a single dose of PCV13 then boosted with a single dose of PPV23.
Study of short and long term immunological response after different schedule of PCV13 or PPV23
Evaluation of pneumococcal nasopharyngeal colonization
Group 4
Immunological and microbiological status of HIV- positive adults that have never received a pneumococcal vaccine (naive) and have a CD4+ cell count > 200 cells/ul that have prescription to be primed with a single dose of PCV13 then boosted with a single dose of PPV23.
Study of short and long term immunological response after different schedule of PCV13 or PPV23
Evaluation of pneumococcal nasopharyngeal colonization
Group 5
Immunological and microbiological status of HIV- positive adults with pneumococcal vaccinal status of 1 PPV23 dose received from more than 3 years and that that have prescription to receive a single dose of PCV13.
Study of short and long term immunological response after different schedule of PCV13 or PPV23
Evaluation of pneumococcal nasopharyngeal colonization

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Immunological response evaluation
Time Frame: 24 months
Dosing of serotype specific antibodies (cut off value: 0.35 mcg/mL for each vaccine polysaccharide antigen) and quantification of number and phenotype of serotype specific B cells
24 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Streptococcus pneumoniae colonization
Time Frame: 24 months
Presence of S. pneumoniae in nasopharyngeal swabs culture
24 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Francesca Montagnani, MD, PhD, Università degli Studi di Siena - Dipartimento di Biotecnologie Mediche - Dipartimento di Malattie Infettive Universitarie

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

January 1, 2015

Primary Completion (Actual)

January 1, 2017

Study Completion (Actual)

January 1, 2017

Study Registration Dates

First Submitted

January 22, 2015

First Submitted That Met QC Criteria

February 2, 2015

First Posted (Estimate)

February 6, 2015

Study Record Updates

Last Update Posted (Estimate)

January 10, 2017

Last Update Submitted That Met QC Criteria

January 9, 2017

Last Verified

January 1, 2017

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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