pneumococcal polysaccharide conjugate vaccine 21-valent

**Pneumococcal polysaccharide conjugate vaccine 21-valent** is a Merck-developed, CRM197-conjugated pneumococcal vaccine marketed as **CAPVAXIVE**. It contains purified capsular polysaccharide antigens from 21 *Streptococcus pneumoniae* serotypes and induces serotype-specific antibodies that enhance opsonization, phagocytosis, and bacterial killing. The de-O-acetylated 15B antigen also elicits functional antibody activity against serotype 15C. In the United States, it is approved as a single intramuscular dose to prevent invasive pneumococcal disease in adults and in children and adolescents aged 2 through 17 years at increased risk for pneumococcal disease; it is also approved for prevention of pneumococcal pneumonia in adults under accelerated approval. ([fda.gov](https://www.fda.gov/media/179426/download))

Brand names

CAPVAXIVE

Other names

PCV21PCV-21PCV 21pneumococcal conjugate vaccine 21-valent