Pneumococcal Polysaccharide Serotype 7F Conjugated To Crm197

This article summarizes clinical trials investigating the use of pneumococcal polysaccharide serotype 7F conjugated to CRM197 vaccine. This vaccine is part of broader pneumococcal conjugate vaccines being studied to prevent pneumococcal disease in various age groups. The trials examine the safety, immune response, and effectiveness of these vaccines containing the 7F serotype, among other pneumococcal serotypes.

Table of Contents

What is the pneumococcal polysaccharide serotype 7F conjugate vaccine?

The pneumococcal polysaccharide serotype 7F conjugate vaccine is a component of broader pneumococcal vaccines that help protect against infections caused by the bacteria Streptococcus pneumoniae, also known as pneumococcus. This specific component targets the 7F serotype of pneumococcus.[1]

The vaccine contains a small amount of the outer sugar coating (polysaccharide) of the 7F pneumococcal bacteria. This polysaccharide is chemically joined (conjugated) to a harmless protein called CRM197. The CRM197 protein helps the immune system respond better to the vaccine.[1]

How does it work?

When the vaccine is injected, your immune system recognizes the pneumococcal polysaccharides as foreign and produces antibodies against them. If you’re later exposed to pneumococcus bacteria, your immune system “remembers” these polysaccharides and can quickly produce antibodies to fight the infection.[1]

The CRM197 protein in the vaccine acts as a carrier, helping to enhance the immune response, especially in young children whose immune systems are still developing.[1]

What diseases does it help prevent?

The pneumococcal polysaccharide serotype 7F conjugate vaccine, as part of broader pneumococcal vaccines, helps prevent several serious diseases caused by pneumococcus bacteria, including:

  • Pneumonia – an infection of the lungs
  • Bacteremia – a blood infection
  • Meningitis – an infection of the lining of the brain and spinal cord
  • Otitis media – middle ear infections (in children)

These diseases can be very serious, especially in young children, older adults, and people with weakened immune systems.[2]

Who should get this vaccine?

The pneumococcal polysaccharide serotype 7F conjugate vaccine is typically included in broader pneumococcal conjugate vaccines (PCVs) recommended for:

  • All infants and young children
  • Adults 65 years or older
  • People aged 18-64 with certain medical conditions that increase their risk of pneumococcal disease

Specific recommendations may vary by country and the exact formulation of the vaccine.[2]

How is it administered?

The vaccine is given as an injection, usually into the muscle of the upper arm or thigh. For infants and young children, it’s typically given as a series of doses at specific ages. Adults usually receive a single dose.[2]

How effective is it?

Studies have shown that pneumococcal conjugate vaccines containing the 7F serotype are highly effective at preventing invasive pneumococcal disease caused by this serotype. In clinical trials, the vaccines have demonstrated good immune responses, with most recipients developing protective levels of antibodies.[3]

Is it safe?

Pneumococcal conjugate vaccines, including those containing the 7F serotype, have been extensively studied and have a good safety profile. They have been used in many countries for years and continue to be monitored for safety.[3]

What are the potential side effects?

Like all vaccines, pneumococcal conjugate vaccines can cause side effects, although not everyone experiences them. Common side effects may include:

  • Pain, redness, or swelling at the injection site
  • Mild fever
  • Irritability (in children)
  • Decreased appetite (in children)
  • Fatigue
  • Headache

These side effects are usually mild and go away on their own within a few days. Serious allergic reactions are very rare.[3]

Ongoing research

Researchers continue to study pneumococcal conjugate vaccines to improve their effectiveness and expand their coverage. Some current areas of research include:

  • Developing vaccines that protect against more pneumococcal serotypes
  • Studying the long-term effectiveness of these vaccines
  • Investigating the impact of these vaccines on pneumococcal disease rates in different populations
  • Exploring new ways to enhance immune responses to the vaccines

For example, one ongoing study is evaluating the safety and immune response of a new 20-valent pneumococcal conjugate vaccine (which includes the 7F serotype) in adults aged 65 and older.[4]

Trial Aspect Details
Vaccine Types 20-valent pneumococcal conjugate vaccine (PCV20), 21-valent pneumococcal conjugate vaccine (V116), 13-valent pneumococcal conjugate vaccine (PCV13)
Age Groups Infants (2 months+), children, adolescents, adults (18-64 with risk factors), older adults (65+)
Primary Objectives Safety, tolerability, immunogenicity, effectiveness against pneumococcal disease
Key Measurements Adverse events, opsonophagocytic activity (OPA), immunoglobulin G (IgG) levels, geometric mean titers (GMTs)
Comparison Vaccines 23-valent pneumococcal polysaccharide vaccine (PPSV23), PCV13
Special Populations Adults with increased risk (e.g., chronic diseases), healthy volunteers
Study Designs Randomized, controlled, multi-country, phase II/III trials

Ongoing Clinical Trials on Pneumococcal Polysaccharide Serotype 7F Conjugated To Crm197

  • Study of Pneumococcal Vaccine Response in Patients Without a Spleen: Comparing Vaccination Before and After Spleen Removal Using PCV20 and PCV21

    Recruiting

    1 1 1 1
    Investigated diseases:
    The Netherlands
  • Study on the Safety and Immune Response of V116 Vaccine for Pneumococcal Disease in Adults Aged 50 and Older

    Not recruiting

    1 1 1 1
    Germany Spain
  • Study on the Safety and Immune Response of a 21-Valent Pneumococcal Conjugate Vaccine in Healthy Infants and Toddlers

    Not recruiting

    1 1 1 1
    Belgium Czechia Estonia Finland Germany Greece +3
  • Study on the Safety and Immune Response of V116 Vaccine in Children and Adolescents at Higher Risk for Pneumococcal Disease

    Not recruiting

    1 1 1 1
    Investigated diseases:
    Finland France Poland Spain Sweden
  • Study on the V116 Vaccine for Adults Aged 18-64 at Increased Risk of Pneumococcal Infection

    Not recruiting

    1 1 1
    Poland

Glossary

  • Pneumococcal polysaccharide: A sugar molecule found on the surface of pneumococcal bacteria that helps trigger an immune response when used in a vaccine.
  • CRM197: A non-toxic mutant of diphtheria toxin used as a carrier protein in conjugate vaccines to enhance the immune response, especially in young children.
  • Serotype: A distinct variation within a species of bacteria, in this case referring to different strains of pneumococcal bacteria with unique surface polysaccharides.
  • Conjugate vaccine: A type of vaccine that joins a weak antigen (like a polysaccharide) to a stronger antigen (like a protein) to improve the immune response, especially in young children.
  • Opsonophagocytic activity (OPA): A measure of antibody function that reflects the ability of antibodies to facilitate the uptake and killing of bacteria by immune cells.
  • Immunoglobulin G (IgG): The most common type of antibody found in blood and other body fluids, playing a crucial role in antibody-mediated immunity against pathogens.
  • Geometric mean titer (GMT): A way of averaging antibody levels across a group of participants, useful for comparing immune responses between different vaccines or groups.
  • Non-inferiority: A statistical concept used in clinical trials to show that a new treatment is not unacceptably worse than an existing treatment.
  • Invasive pneumococcal disease: A severe infection caused by pneumococcal bacteria entering normally sterile sites like the bloodstream or spinal fluid.
  • Community-acquired pneumonia (CAP): Pneumonia acquired outside of a healthcare setting, often caused by pneumococcal bacteria among other pathogens.

References

  1. http://clinicaltrials.eu/trial-id/2022-501519-15-00
  2. http://clinicaltrials.eu/trial-id/2022-502791-22-01
  3. http://clinicaltrials.eu/trial-id/2022-503144-40-00
  4. http://clinicaltrials.eu/trial-id/2023-507293-40-00