MSD (trade name of Merck & Co.) has announced that Singapore's Health Sciences Authority (HSA) has approved Capvaxive (Pneumococcal 21-valent Conjugate Vaccine) for the active immunisation of adults aged 18 years and above against Invasive Pneumococcal Disease (IPD) and pneumonia caused by 21 specified serotypes of Streptococcus pneumoniae.

The approved vaccine covers serotypes 3, 6A, 7F, 8, 9N, 10A, 11A, 12F, 15A, 15B, 15C, 16F, 17F, 19A, 20A, 22F, 23A, 23B, 24F, 31, 33F and 35B.

Capvaxive is a pneumococcal conjugate vaccine developed to protect adults against invasive pneumococcal disease and pneumococcal pneumonia caused by the indicated serotypes. According to MSD, among adults who have previously received other pneumococcal vaccines, subsequent vaccination with Capvaxive is estimated to provide combined serotype coverage of 78 percent against those causing invasive pneumococcal disease.

The approval introduces an additional adult-focused Pneumococcal Conjugate Vaccine (PCV) option in Singapore, addressing changes in the distribution of pneumococcal serotypes responsible for adult IPD over time. Capvaxive was previously approved in the United States in June 2024, Canada in July 2024 and Australia in February 2025, before receiving approval in Singapore in February 2026.

Pneumococcal disease is caused by the bacterium Streptococcus pneumoniae, which comprises multiple serotypes. The disease is associated with significant morbidity and mortality among adults worldwide, with its incidence varying according to age, geographical region and other population factors.

The risk of severe disease and mortality is higher among older adults, individuals with underlying health conditions such as diabetes, chronic lung disease and chronic liver disease, and immunocompromised people, including those living with HIV, cancer patients, transplant recipients and individuals receiving immunosuppressive therapies.

Pneumococcal disease is classified into invasive pneumococcal disease and non-invasive pneumococcal disease. IPD occurs when the bacteria enter normally sterile parts of the body, including the bloodstream or brain. The emergence of antibiotic-resistant pneumococcal strains and the replacement of vaccine-covered serotypes by non-vaccine serotypes remain important public health concerns.

Adult invasive pneumococcal disease has been reported in Singapore across multiple surveillance years. With the latest HSA approval, Capvaxive provides an additional pneumococcal vaccination option for eligible adults and is now available for administration by relevant healthcare providers in Singapore.