Rare diseases
Investigational molecules
Locations
Pneumococcal Polysaccharide Serotype 6B is a purified sugar molecule (polysaccharide) from the outer coating of the bacterium Streptococcus pneumoniae, specifically serotype 6B. In the vaccine Synflorix, this polysaccharide is chemically linked (conjugated) to a carrier protein derived from non-typeable Haemophilus influenzae and adsorbed onto aluminium phosphate as an adjuvant.[1]
The substance is one of ten pneumococcal polysaccharide components in Synflorix, a pneumococcal polysaccharide conjugate vaccine authorised in the European Union under authorisation records EU/1/09/508/002 through EU/1/09/508/005. The marketing authorisation holder is GlaxoSmithKline Biologicals S.A.[1] In the CTIS records, the substance appears as an auxiliary medicine in six trials, meaning it is part of the vaccine product used rather than the main investigational substance under study.[1]
Other pneumococcal serotypes in the same vaccine include serotypes 1, 4, 5, 7F, 9V, 14, 18C, 19F and 23F, each conjugated to protein D or to tetanus or diphtheria toxoid carrier proteins.[1]
Pneumococcal conjugate vaccines work by presenting the polysaccharide from the bacterial capsule to the immune system. Linking the polysaccharide to a carrier protein converts it from a T-cell-independent antigen into a T-cell-dependent antigen, which produces a stronger and longer-lasting immune response, especially in young children.[4]
The resulting antibodies recognise the pneumococcal capsule and mark the bacteria for destruction by immune cells, a process called opsonophagocytosis. This opsonophagocytic killing (OPK) activity is the main laboratory measure used to assess how well pneumococcal vaccines work.[4]
Serotype 6B is described in the medical literature as a serotype with low invasive potential, meaning it behaves as an opportunistic pathogen in at-risk individuals rather than as a primary pathogen in previously healthy people.[3]
The substance is formulated as a suspension for injection, administered by intramuscular use. In the CTIS product records, the pharmaceutical form is a 0.5 ml dose in a pre-filled syringe.[1] The Phase 2 trial used the same 0.5 ml intramuscular dose for all study arms, including the monovalent candidate containing serotype 6B.[1]
Synflorix, the authorised vaccine containing this substance, is given to infants as part of routine childhood immunisation programmes.[2]
One completed Phase 2 trial (EU CT number 2023-505154-18-00) investigated a monovalent pneumococcal conjugate candidate in 100 healthy toddlers aged 11 to 15 months.[1] The trial was interventional and compared the monovalent candidate against Synflorix, the authorised pneumococcal polysaccharide conjugate vaccine, and another candidate containing pneumococcal polysaccharide serotype 3 conjugated to CRM197.[1]
The primary outcomes measured safety and tolerability: prompted local reactions (redness, swelling and pain at the injection site), prompted systemic events (fever, decreased appetite, drowsiness or increased sleep, and irritability), adverse events, and serious adverse events.[1] The trial aimed to describe the safety profile of the monovalent candidate when given as a two-dose series.[1]
Because the substance appears as an auxiliary medicine in the CTIS records, the main focus of the research was on the monovalent candidate rather than on Synflorix itself. The trial status is completed, meaning the study has finished and results may be available in the registry.[1]
The trial measured local reactions at the injection site, including redness, swelling and pain, as well as systemic events such as fever, decreased appetite, drowsiness or increased sleep, and irritability.[1] These are the expected reactions that pneumococcal conjugate vaccines can cause in young children. The trial also recorded adverse events and serious adverse events to assess the overall safety profile of the vaccine candidate.[1]
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.
