This past summer, the FDA approved Prevnar 20 (Pneumococcal 20-valent Conjugate Vaccine) for the prevention of invasive disease and pneumonia caused by the 20 different Streptococcus pneumoniae (pneumococcus) serotypes in the vaccine in adults aged 18 years and older.

Recently, a workgroup of the CDC has been meeting to discuss and, ultimately, update recommendations on the safe and appropriate use of pneumococcal vaccines in adults.

A recent study points out that pneumococcal conjugate vaccines (PCVs) have significantly reduced pneumococcal disease, but significant disease from non-PCV serotypes remains. Researchers sought to determine the safety, tolerability, and immunogenicity of a 20-valent PCV (PCV20), which was developed because more than half of all cases of invasive pneumococcal disease (IPD)—which include bacteremia and meningitis—in adults aged 65 years or older are due to the 20 serotypes in that vaccine. Their results were published in the journal Clinical Infectious Diseases.

The industry-sponsored phase III, randomized, double-blind study enrolled adults into three age groups—60 years or older, 50 to 59 years, and 18 to 49 years—at U.S. and Swedish sites. Participants were randomized to receive one PCV20 or PCV13 dose. After 1 month, the oldest group of participants also received one dose of saline or the 23-valent polysaccharide vaccine (PPSV23).

The study team assessed safety issues, including local reactions, systemic events, adverse events, serious adverse events, and newly diagnosed chronic medical conditions.

The study found that severity and frequency of prompted local reactions and systemic events were similar after PCV20 or PCV13, with no safety concerns identified.

Researchers also reported that primary immunogenicity objectives were met, with immune responses after PCV20 noninferior to 13 matched serotypes after PCV13 and to six additional PPSV23 serotypes in participants aged 60 years or older, although serotype 8 missed the statistical noninferiority criterion. PCV20 induced robust responses to all 20 vaccine serotypes across age groups, they emphasized.

"PCV20 was safe and well-tolerated, with comparable immunogenicity to PCV13/PPSV23. PCV20 is anticipated to expand protection against pneumococcal disease in adults," the study concluded.

Prevnar 20 includes capsular polysaccharide conjugates for the 13 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) already included in Prevnar 13 (Pneumococcal 13-valent Conjugate Vaccine [Diphtheria CRM Protein]). The vaccine also contains capsular polysaccharide conjugates for seven additional serotypes (8, 10A, 11A, 12F, 15B, 22F, and 33F) that cause IPD and have been associated with high case-fatality rates, antibiotic resistance, and/or meningitis, according to a Pfizer press release.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

« Click here to return to Vaccine Update.