Vaxcyte Pneumococcal Vaccines Clinical Trials, Indication, Side Effects
Vaxcyte Inc.'s carrier-sparing Pneumococcal Vaccine (PCV) franchise candidates VAX-24, a 24-valent PCV, and VAX-31, a 31-valent PCV, are being studied for the prevention of invasive pneumococcal disease (IPD). Both VAX-24 and VAX-31 are designed to improve upon the standard-of-care PCVs for both children and adults by covering the serotypes that are responsible for a significant portion of IPD in circulation and are associated with high case-fatality rates, antibiotic resistance, and meningitis while maintaining coverage of previously circulating strains that are currently contained through continued vaccination practice.
Vaxcyte is re-engineering the way highly complex vaccines are made through modern synthetic techniques, including advanced chemistry and the XpressCF™ cell-free protein synthesis platform, exclusively licensed from Sutro Biopharma, Inc. Unlike conventional cell-based approaches, the Company's system for producing difficult-to-make proteins and antigens is intended to accelerate its ability to efficient create and deliver high-fidelity vaccines with enhanced immunological benefits disease (PD) is an infection caused by Streptococcus pneumonia (pneumococcus) bacteria. It can result in IPD, including meningitis and bacteremia, and non-invasive PD, including pneumonia, otitis media, and sinusitis.
Grant Pickering, Chief Executive Officer and Co-founder of Vaxcyte commented in a press release on November 6, 2024, "We are exceptionally proud of the significant progress we have made across the adult and infant clinical programs for our broad-spectrum, carrier-sparing pneumococcal conjugate vaccine (PCV) candidates, VAX-31 and VAX-24. We believe the recent topline results for VAX-31 in adults demonstrate its potential as a best-in-class PCV to provide protection against both currently circulating and historically prevalent strains while setting a new standard for immunogenicity. For the adult indication, we look forward to moving VAX-31 into a Phase 3 program and plan to initiate the pivotal non-inferiority study by mid-2025. For the pediatric indication, we anticipate delivering the topline data from the primary immunization series of the VAX-24 Phase 2 study by the end of the first quarter of 2025, followed by topline data from the booster dose by the end of 2025. In addition, we plan to initiate the VAX-31 infant Phase 2 study in the first quarter of 2025, subject to IND application clearance by the end of this year."
Vaxcyte (Nasdaq: PCVX) is a vaccine innovation company engineering high-fidelity vaccines to protect humankind from the consequences of bacterial diseases. On September 4, 2024, Vaxcyte announced that it had commenced an underwritten public offering of $1.4 billion of its common stock and pre-funded warrants.
VAX-24 Vaccine
VAX-24 is an investigational 24-valent PCV candidate designed to prevent IPD, which can be most serious for infants, young children, older adults, and those with immune deficiencies or certain chronic health conditions. In July 2024, the results from the VAX-24 Phase 2 study in adults aged 65 and older were published in the journal Vaccine. The study evaluated the safety, tolerability and immunogenicity of Vaxcyte's investigational 24-valent, carrier-sparing PCV compared to Prevnar 20® (PCV20), for the prevention of invasive pneumococcal disease (IPD) in healthy adults. The results showed that VAX-24 demonstrated a safety and tolerability profile comparable to PCV20 across all ages and doses studied. The VAX-24 2.2mcg dose showed an overall improvement in immune responses compared to PCV20 relative to the results from the prior Phase 2 study in adults aged 50-64. The U.S. FDA awarded VAX-24 Breakthrough Therapy Designation on January 5, 2023, and cleared the Company's infant Investigational New Drug application for VAX-24 on February 21, 2023.
VAX-31 Vaccine
VAX-31 is a next-generation PVC vaccine and is the broadest-spectrum PCV candidate in the clinic today. As of September 2024, the Company had initiated a full complement of expected Phase 3 studies in 2025 and 2026.
Vaxcyte Inc. News
September 3, 2024 - The Company presented topline results from the Phase 1/2 study evaluating the safety, tolerability, and immunogenicity of VAX-31 in healthy adults aged 50 and older.
August 6, 2024 - The Company announced it had cash, cash equivalents, and investments of $1,851.9 million as of June 30, 2024, compared to $1,242.9 million as of December 31, 2023.
January 4, 2024 - Mr. Grant Pickering commented in a press release, "We also received encouraging feedback from the FDA regarding the licensure requirements for VAX-24 in adults. We are fortunate to be afforded these ongoing discussions, given the Breakthrough Therapy designation granted to VAX-24, and expect to seek additional CMC-focused input from regulators as we prepare for and conduct the adult Phase 3 program, which will comprise several studies. With VAX-24 and VAX-31, we are confident in our plans to build a best-in-class PCV franchise that delivers the broadest spectrum of coverage against invasive pneumococcal disease."
July 11, 2023 - Vaxcyte, Inc. announced that the ongoing Phase 2 study of VAX-24 in healthy infants is advancing to the second and final stage of the study.
Vaxcyte Vaccine Clinical Trials
VAX-24 Infant Phase 2 Study - The VAX-24 infant Phase 2 clinical study, which is now fully enrolled with 802 healthy infants, is a randomized, observer-blind, dose-finding two-stage clinical study evaluating the safety, tolerability, and immunogenicity of VAX-24. The Stage 1 portion of the study evaluated the safety and tolerability of a single injection of VAX-24 at three dose levels (low dose/1.1mcg, middle dose/2.2mcg, mixed dose/2.2mcg or 4.4mcg) and compared to VAXNEUVANCE™ (PCV15), which was the broadest-spectrum PCV at the time of study initiation, in 48 infants. The Stage 2 portion evaluates the safety, tolerability, and immunogenicity of VAX-24 at the same three dose levels and compared to Prevnar 20® (PCV20), currently the broadest-spectrum PCV recommended by the Advisory Committee on Immunization Practices (ACIP), in 754 infants. Participants who received VAX-24 in Stage 1 will continue the standard dosing regimen as part of Stage 2 and will be included in the study's safety, tolerability, and immunogenicity analysis.