“Prevenar 20 could address roughly half of pneumococcal infection cases in Korea.”

Prevenar 20 is Pfizer Korea's first new pneumococcal conjugate vaccine since the approval of Prevenar 13 in 2010.

At a press conference on Tuesday marking the domestic approval of the vaccine, Professor Park Su-eun of pediatrics at Pusan National University School of Medicine said the vaccine is expected to be “particularly effective against serotype 10A, which is highly prevalent in Korea.”

Prevenar 20 is a 20-valent vaccine that expands on the 13 serotypes covered by Prevenar 13 by adding seven more—serotypes 8, 10A, 11A, 12F, 15B, 22F, and 33F—providing the broadest serotype coverage among pneumococcal conjugate vaccines approved in Korea.

The Ministry of Food and Drug Safety approved Prevenar 20 on Oct. 31, allowing its use for preventing invasive pneumococcal diseases and pneumonia in infants, children, adolescents (six weeks to under 18 years), and adults (18 years and older). The release date and potential joint sales agreements for Prevenar 20 have not yet been determined.

Despite a decline in pneumococcal disease incidence due to national vaccination programs, Professor Park emphasized that it remains a significant cause of infections, particularly because serotypes not covered by the 13-valent vaccine continue to contribute to the disease burden.

“Approximately 90 percent of invasive pneumococcal disease cases in Korean children from January 2018 to December 2020 involved serotypes not covered by the 13-valent vaccine,” she said, referencing a study that found 51 out of 57 cases were caused by these serotypes. Another study from 2014 to 2019 showed that 24 percent of 168 pneumococcal infections in Korean children were caused by serotype 10A.

Further analysis of 67 pneumococcal strains isolated from infected pediatric patients in Korea between January 2018 and July 2021 revealed that the 20 serotypes covered by Prevenar 20— including the most frequently identified serotypes 10A (20 cases) and 15B (6 cases)—accounted for approximately 54 percent of all cases. 

Similarly, an analysis of 116 strains from adult patients showed that 53 percent of cases were caused by serotypes covered by Prevenar 20. According to Professor Park, this suggests that Prevenar 20 could address roughly half of pneumococcal infection cases in Korea.

While Prevenar 20 offers broader coverage, its side effect profile is similar to that of Prevenar 13. Phase 3 clinical trials demonstrated its immunogenicity and safety for both the 13 shared serotypes and the additional seven serotypes in children, as well as in adults, compared to Merck's 23-valent pneumococcal polysaccharide vaccine, Pneumovax 23.

Kim Sun-ju, primary care medical lead of medical affairs at Pfizer Korea, noted that Prevenar 20 showed strong immunogenicity and good tolerability across all 20 serotypes when administered as a four-dose series to healthy infants.

“For adults, Prevenar 20 showed tolerability similar to Prevenar 13 for the shared serotypes, with confirmed immunogenicity data for both the shared serotypes and the additional seven serotypes compared to Pneumovax 23,” she explained.

Professor Park added that Prevenar 20 caused similar adverse reactions to Prevenar 13, with no serious adverse events reported. "Based on these results, the vaccine has been approved in many countries, including the U.S., Europe, and Japan,” she said.

Kim Eun-ji, marketing lead at Pfizer Korea, noted that Prevenar 13 will not be withdrawn from the market despite the introduction of Prevenar 20. Currently, Prevenar 13 is co-marketed, but it is still undecided whether Prevenar 20 will follow the same path or which company will manage its sales.