In short
This article summarizes clinical trials investigating the use of a pneumococcal vaccine containing pneumococcal polysaccharide serotype 7F conjugated to CRM197 and adsorbed on aluminium phosphate. The vaccine is being studied for prevention of pneumococcal disease in various populations, including healthy adults, infants, and those at increased risk. The trials examine the vaccine's safety, immunogenicity, and effectiveness when given alone or in combination with other vaccines.
What is the pneumococcal polysaccharide serotype 7F conjugate vaccine?
The pneumococcal polysaccharide serotype 7F conjugate vaccine is a component of several pneumococcal conjugate vaccines, including the 13-valent (PCV13) and 20-valent (PCV20) vaccines. It contains the capsular polysaccharide from the 7F serotype of Streptococcus pneumoniae bacteria, which is chemically linked (conjugated) to a carrier protein called CRM197 and adsorbed onto an aluminum phosphate adjuvant.
This vaccine is also known by the following names:
- Pneumococcal polysaccharide serotype 7F conjugated to CRM197 adsorbed on aluminium phosphate
- Pneumococcal polysaccharide serotype 7F conjugated to CRM197 carrier protein adsorbed on aluminium phosphate
How does it work?
The vaccine works by stimulating the immune system to produce antibodies against the capsular polysaccharide of the 7F serotype of S. pneumoniae. The conjugation to the CRM197 protein helps to enhance the immune response, particularly in young children. The aluminum phosphate adjuvant further boosts the immune response.
When vaccinated individuals are later exposed to the 7F serotype of S. pneumoniae, their immune system recognizes the bacteria and can mount a rapid and effective response to prevent infection.
What is it used for?
This vaccine component helps protect against invasive pneumococcal disease and pneumonia caused by the 7F serotype of S. pneumoniae. It is included in broader pneumococcal conjugate vaccines that protect against multiple serotypes.
Pneumococcal disease can cause serious infections including:
- Pneumonia (lung infection)
- Bacteremia (blood infection)
- Meningitis (infection of the coverings of the brain and spinal cord)
- Otitis media (middle ear infection)
How is it administered?
The pneumococcal conjugate vaccines containing this component are given as an intramuscular injection, typically in the thigh for infants or the upper arm for older children and adults. The dosing schedule depends on the specific vaccine and the age at which vaccination is started.
How effective is it?
Clinical trials have shown that pneumococcal conjugate vaccines containing the 7F serotype are highly effective at preventing invasive pneumococcal disease caused by this strain. The effectiveness can vary depending on factors like age and immune status of the recipient.
What are the potential side effects?
Common side effects of pneumococcal conjugate vaccines may include:
- Pain, redness, or swelling at the injection site
- Fever
- Irritability
- Decreased appetite
- Increased or decreased sleep
Serious allergic reactions are rare but possible. Patients should seek immediate medical attention if they experience symptoms of a severe allergic reaction after vaccination.
Who should get this vaccine?
Pneumococcal conjugate vaccines containing the 7F serotype are recommended for:
- Infants and young children as part of their routine vaccination schedule
- Adults 65 years and older
- Individuals with certain medical conditions that increase their risk of pneumococcal disease
The specific recommendations may vary by country and individual risk factors. Patients should consult with their healthcare provider to determine if and when they should receive a pneumococcal vaccine.
Ongoing research
Researchers continue to study pneumococcal conjugate vaccines to assess their long-term effectiveness, impact on pneumococcal disease rates, and potential for preventing conditions like community-acquired pneumonia in adults. Some current clinical trials are evaluating:
- The effectiveness of 20-valent pneumococcal conjugate vaccine (which includes the 7F serotype) against vaccine-type radiologically-confirmed community-acquired pneumonia in adults aged 65 and older
- Co-administration of pneumococcal conjugate vaccines with other vaccines like those for respiratory syncytial virus (RSV)
- Use of pneumococcal conjugate vaccines in specific populations like adults with increased risk for pneumococcal disease
These ongoing studies will help to further refine vaccination strategies and potentially expand the use of pneumococcal conjugate vaccines to protect more people from pneumococcal infections.