In short
PF-07872449 is an investigational pneumococcal vaccine being studied for pneumococcal immunisation. It is being tested in two authorised Phase 3 trials involving a total of 3,600 healthy infants, children and adolescents. The trials compare the safety and immune response of PF-07872449 with Prevenar 20, an already available pneumococcal vaccine.
Key points
- PF-07872449 is being studied for pneumococcal immunisation in healthy infants, children and adolescents.
- Both clinical trials are Phase 3 studies, the most advanced stage before a medicine can be considered for approval.
- The first trial includes 2,400 healthy infants and focuses on the safety of the vaccine.
- The second trial includes 1,200 healthy children and adolescents and measures both safety and immune response.
- The main outcomes measured are local reactions (redness, swelling, pain at the injection site) and systemic events (fever, fatigue, irritability).
- Both trials are currently authorised, meaning they have received regulatory approval to begin.
What is PF-07872449?
PF-07872449 is an investigational pneumococcal vaccine. It is being studied for pneumococcal immunisation, which means protecting people against infections caused by the bacterium Streptococcus pneumoniae. This bacterium can cause serious illnesses such as pneumonia, meningitis and bloodstream infections. The substance is not yet authorised as a medicine; it is currently being tested in clinical trials.
How does PF-07872449 work?
The clinical trial records do not provide a detailed description of the mechanism of action of PF-07872449. As a pneumococcal vaccine, it is expected to help the immune system recognise and defend against pneumococcal bacteria. The trials are measuring immune responses such as pneumococcal serotype-specific IgG concentrations and OPA titers, which indicate how well the immune system responds to the vaccine.
Which conditions is PF-07872449 studied for?
- Pneumococcal immunisation — protection against infections caused by Streptococcus pneumoniae, including pneumonia, meningitis and bloodstream infections. Both trials are studying this in healthy infants, children and adolescents.
How is PF-07872449 given?
PF-07872449 is given as an injection into the muscle (intramuscular). In the trial records, the dose is listed as 0.5 millilitres. It is being compared with Prevenar 20, a pneumococcal polysaccharide conjugate vaccine (20-valent, adsorbed) that is already available and is also given as an intramuscular injection.
What do the clinical trials show?
Two authorised Phase 3 clinical trials are investigating PF-07872449. Both are interventional studies, meaning participants receive the vaccine and are then monitored. The first trial (2025-523447-35-02) includes 2,400 healthy infants and focuses on describing the safety profile of the vaccine. The second trial (2025-523445-10-00) includes 1,200 healthy children and adolescents and looks at both safety and the kind of immune response generated.
The trials measure several outcomes. These include prespecified local reactions such as redness, swelling and pain at the injection site, and prespecified systemic events such as fever, decreased appetite, irritability and drowsiness. In the trial with children and adolescents, additional systemic events are measured depending on age: fatigue, headache, muscle pain and joint pain. The second trial also measures pneumococcal serotype-specific IgG concentrations and OPA titers, which are laboratory tests showing how well the immune system responds to the vaccine.
Who can take part in these trials?
The trials are enrolling healthy participants. The first trial is for healthy infants. The second trial is for healthy children and adolescents, divided into age groups: children from 15 months to under 24 months, and children and adolescents from 2 years to under 18 years. Both trials are currently authorised, meaning they have received regulatory approval to begin.
What side effects are known?
The clinical trial records do not provide a list of known side effects for PF-07872449. The trials are designed to collect information on side effects, including local reactions at the injection site and systemic events such as fever and irritability. Adverse events and serious adverse events are being recorded as part of the primary outcomes in both trials.