Rare diseases
Investigational molecules
Locations
Pneumococcal polysaccharide serotype 1 conjugated to CRM197 is one of the active components in pneumococcal conjugate vaccines. These vaccines are designed to protect against infections caused by the bacterium Streptococcus pneumoniae, which can cause pneumonia, meningitis, and bloodstream infections. In the registered trial, this serotype is part of a 21-valent pneumococcal conjugate vaccine (PCV21) being studied in healthy infants.[1]
Pneumococcal polysaccharide serotype 1 conjugated to CRM197 is a vaccine component. It consists of the polysaccharide (sugar) coating from pneumococcal serotype 1, chemically linked (conjugated) to a carrier protein called CRM197, which is a non-toxic variant of diphtheria toxin. This conjugation helps the immune system, especially in infants, to recognise and respond to the polysaccharide.[3] The substance is part of the product records for a 21-valent pneumococcal conjugate vaccine (PCV21) and also appears in a 15-valent vaccine called Vaxneuvance.[1] In the registered trial, PCV21 is the test product and Vaxneuvance (15vPCV) is the comparator.[1] The substance is authorised as a medicine in the European Union, with authorisation record EU/1/21/1591/003, held by Sanofi Pasteur Inc. and Merck Sharp & Dohme B.V.[1]
Conjugate vaccines work by linking a bacterial polysaccharide to a protein carrier. The polysaccharide alone does not produce a strong immune response in young children, but when conjugated to CRM197, the immune system recognises the combination and produces antibodies against the polysaccharide. These antibodies target the surface of Streptococcus pneumoniae bacteria, helping the body to prevent infection.[3] The trial measures the antibody response (immunoglobulin G, or IgG) against pneumococcal serotypes, including serotype 1, to assess how well the vaccine works.[1]
The vaccine containing pneumococcal polysaccharide serotype 1 conjugated to CRM197 is given as a suspension for injection by intramuscular injection.[1] The registered trial uses a 0.5 ml dose.[1] In the supplementary sources, Synflorix, another pneumococcal conjugate vaccine containing serotype 1, is also given as a suspension for injection by intramuscular use in a 0.5 ml dose.[2]
One registered clinical trial (2023-507600-32-00) investigates PCV21, which includes pneumococcal polysaccharide serotype 1 conjugated to CRM197. The trial is a Phase 3 interventional study in healthy infants from approximately 2 months of age, with 1,113 participants enrolled.[1]
The primary outcomes measure the antibody response (IgG) against PCV21 and 15vPCV serotypes. The trial aims to demonstrate that PCV21 is non-inferior to 15vPCV for the shared serotypes, and superior for the six serotypes unique to PCV21, at 30 days after the toddler dose.[1]
The trial is currently authorised, meaning it has received approval to proceed. The study involves full-term and preterm infants, with the immune response assessed after the toddler dose (post dose 3 for full-term infants and post dose 4 for preterm infants).[1]
Information on side effects comes from a World Health Organization prequalification document for BE-PCV14, a 14-valent pneumococcal conjugate vaccine that also contains serotype 1 conjugated to CRM197. The most common adverse events reported are injection site pain or tenderness, fever, and injection site redness. There is a remote chance of a severe allergic reaction, which may very rarely occur after vaccination; signs can include difficulty breathing and rash all over the body.[3]
Each condition opens its own overview and trial list
Recruiting trials first
Tell us about your condition – we search every trial in Europe and connect you with the right site.
