Enrollment Complete: VAX-31 Phase 1/2 Trial for Elderly IPD Prevention

Vaxcyte, a clinical-stage vaccine company, has completed enrollment for its Phase 1/2 study of VAX-31, a vaccine candidate aimed at preventing invasive pneumococcal disease in adults over 50. The study will assess the vaccine's safety, tolerability, and ability to provoke an immune response. The company anticipates sharing preliminary data in the third quarter of 2024.

VAX-31 is a 31-valent pneumococcal conjugate vaccine, meaning it contains 31 different antigens to stimulate an immune response against various strains of pneumococcus bacteria. The vaccine is designed to cover approximately 95% of invasive pneumococcal disease circulating in the U.S. adult population, offering broader protection than existing vaccines.

The Phase 1/2 study is a randomized, observer-blind, active-controlled trial with 1,015 participants aged 50 and older. It is divided into two parts: Phase 1, which evaluated the vaccine's safety and tolerability in 64 adults aged 50 to 64, and Phase 2, which will assess these factors in 951 adults aged 50 and older. The study's immunogenicity objectives include evaluating antibody responses to the vaccine using specific tests.

Pneumococcal disease, caused by Streptococcus pneumoniae, can lead to serious conditions such as meningitis and bacteremia. In the U.S., it is a significant health concern, with thousands of hospitalizations and deaths each year. The development of antibiotic resistance in some strains of the bacteria further emphasizes the importance of effective vaccines.

Vaxcyte's pipeline includes VAX-24, a 24-valent pneumococcal conjugate vaccine in Phase 3, and VAX-31, which is currently in Phase 1/2 trials. Both vaccines are designed to provide broader protection against pneumococcal disease, covering serotypes associated with high mortality rates, antibiotic resistance, and meningitis.

The company uses modern synthetic techniques and a cell-free protein synthesis platform to create high-fidelity vaccines. This approach allows for the efficient development of vaccines with enhanced immunological benefits. Vaxcyte's mission is to protect against bacterial diseases through innovative vaccine development, with a focus on eradicating or treating invasive bacterial infections that pose serious health risks.