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This is one of the vaccines that protects against RSV

Relevant Terms

  • Antibody: a protein made by the immune system in response to a foreign particle (antigen). These proteins circulate in the blood and help defend the body against the substance.  

  • Antigen: This is any substance that triggers the immune system to create antibodies. For example, allergens such as pollen are antigens. 

  • Attenuated: The pathogen is weakened but not completely inactivated. Attenuated pathogens are too weak to cause disease in almost all people.

  • Genome: all of the genetic information in a cell. 

  • pH: a measure of how acidic or basic a solution is. The scale ranges from 0 (very acidic) to 14 (very basic). A pH of 7 is neutral.

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Last updated: Mar. 1, 2023

Active ingredients:

The active ingredient in this vaccine is recombinant RSVPreF3 antigen

RSVPreF3 is a glycoprotein (a protein with a sugar attached to it).

This is a recombinant protein vaccine, which means that the instructions to make  are inserted into the genome of cells so that they produce the proteins. 

This vaccine also contains an adjuvant called AS01E, which contains 2 ingredients: MPL and QS-21. MPL is derived from a species of bacteria called Salmonella minnesota, and QS-21 is derived from the soap bark tree. QS-21 is also used as an adjuvant in a treatment for leukemia (a type of cancer) in cats.

Note: this vaccine contains trace amounts of DNA and proteins from the cells used to produce the surface antigen. These cells are Chinese hamster ovary cells. 

Inactive ingredients:
Amounts are based on a 0.5 mL dose

Salts: help maintain the stability and pH of the vaccine

Carbohydrates (sugars): normally used as stabilizers in vaccines

Lipids (fats): lipids do not dissolve in water, so they are used to create a protective coating around the active ingredient. This coating is also called a liposome.

Other Stabilizers:


Last updated: Sep. 9, 2023

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