|Articles|January 5, 2023

Vaxcyte’s Pneumococcal Vaccine Receives FDA Breakthrough Therapy Designation

Author(s)Nina Cosdon

The 24-valent investigational pneumococcal conjugate vaccine, VAX-24, met its primary endpoints in a phase 1/2 trial.

Today, Vaxcyte, Inc. announced that their 24-valent investigational pneumococcal conjugate vaccine, VAX-24, received Breakthrough Therapy designation from the US Food and Drug Administration (FDA).

The FDA granted the designation in response to positive topline results from a phase 1/2 proof-of-concept study, which evaluated the safety and efficacy of VAX-24 to prevent invasive pneumococcal disease in adults 18-64 years of age.

“The FDA’s Breakthrough Therapy designation supports further acceleration of the VAX-24 development program in adults, while also providing validation of the potential of VAX-24 to deliver broader coverage and better immune responses relative to the standard of care,” said Grant Pickering, Vaxcyte CEO and cofounder.

With this designation, Vaxcyte can utilize the FDA’s Fast Track program, as well as receive FDA guidance and support.

Pneumococcal disease, caused by Streptococcus pneumoniae (pneumococcus) bacteria, is most severe in infants, young children, older adults, and others with immune deficiencies or chronic health conditions. It can result in invasive pneumococcal disease, potentially causing meningitis, bacteremia, pneumonia, otitis media, and sinusitis.

There are antibiotics available to treat pneumococcal disease, but some strains of bacteria have developed resistance, emphasizing the need for an effective vaccine.

In the phase 1/2 clinical trial, VAX-24 met its primary safety and tolerability endpoints. Administered as a 2.2 mcg dose, the investigational pneumococcal vaccine candidate met or exceeded the regulatory immunogenicity standards for all 24 serotypes.

With these favorable results, Vaxcyte intends to proceed with a phase 3 study of VAX-24.

“Our focus remains on advancing our VAX-24 clinical programs in both adults and infants,” said Pickering. “We anticipate announcing the topline data from the Phase 2 study in adults 65 and older in the second quarter of 2023.”

Approximately 900000 people contract pneumococcal pneumonia in the US each year. Of these infections, 150000 will result in hospitalization and 28000 in death. Pneumococci are responsible for over 50% of all US bacterial meningitis cases.


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