VAX-31 Phase 1/2 Study Topline Results in Adults Aged 50 and Older September 3, 2024 Forward-Looking Statements This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, statements related to the potential benefits of Vaxcyte's vaccine candidates, including breadth of coverage, the ability to deliver a potentially best-in-class pneumococcal conjugate vaccine franchise and the potential t ...

Company Overview - Vaxcyte (PCVX) is a clinical-stage biotech company focused on developing vaccines for bacterial infectious diseases [1] - The company's shares have experienced a significant decline of 56% in the past month due to mixed results from a phase II study on its pneumococcal conjugate vaccine (PCV) [1][3] Stock Performance - Year-to-date, Vaxcyte's shares have plummeted over 62%, significantly underperforming the industry, which has seen an 8% decline [3] - The stock is trading below its 50 and 200-day moving averages, indicating weak market sentiment [3] Vaccine Study Results - Vaxcyte's recent mid-stage study evaluated its 24-valent PCV VAX-24 against Pfizer's Prevnar 20, which is approved for preventing invasive pneumococcal disease caused by 20 serotypes [6] - The mid-dose of VAX-24 met non-inferiority criteria for seroconversion and showed robust immune responses, but did not meet the criteria for four of the 24 serotypes compared to Prevnar 20, contributing to the stock's decline [7] - VAX-24 was well-tolerated and demonstrated a safety profile similar to Prevnar 20, with strong markers for protection against invasive pneumococcal disease [8] Future Development Plans - Based on the study results, Vaxcyte plans to advance the mid-dose formulation of VAX-24 into late-stage development [9] - The company is also conducting a mid-stage study on its investigational 31-valent PCV vaccine VAX-31, with top-line results expected in mid-2026, and plans to start a phase III study in infants with either VAX-24 or VAX-31 [10] Industry Context - The broader biotech and drug sector is facing challenges, including the resignation of a senior FDA official, raising concerns about the agency's ability to maintain innovation and regulatory clarity [2]

Core Insights - Vaxcyte, Inc. announced positive topline results from its Phase 2 dose-finding study for VAX-24, a 24-valent pneumococcal conjugate vaccine (PCV) candidate, demonstrating safety and immunogenicity comparable to Prevnar 20® (PCV20) in healthy infants [2][3][4] Group 1: VAX-24 Study Results - VAX-24 was well-tolerated across all evaluated doses, with a safety profile similar to PCV20, and no serious adverse events related to the vaccine were reported [3][4] - Substantial immune responses were elicited post-primary three-dose immunization series, with robust IgG and opsonophagocytic assay (OPA) responses observed across all doses [4][5] - The mid dose of VAX-24 (2.2 mcg) was selected for further development based on its ability to meet non-inferiority criteria and generate robust immune responses [5][6] Group 2: Future Development Plans - The company plans to advance VAX-24 to a potential Phase 3 program, pending topline data from the VAX-31 Phase 2 study expected in mid-2026 [2][6] - Vaxcyte is also introducing VAX-XL, a third-generation PCV candidate aimed at expanding the spectrum of coverage against pneumococcal disease [2][6] - Key milestones include the initiation of a Phase 3 infant program with either VAX-24 or VAX-31 and the announcement of additional data from ongoing studies [8][10][11] Group 3: Study Design and Participant Information - The VAX-24 Phase 2 study is a randomized, observer-blind, dose-finding study involving 802 healthy infants, assessing safety, tolerability, and immunogenicity [7][9] - The study design includes a primary immunization series of three doses followed by a booster dose, with ongoing evaluations of immunogenicity and safety [9][10] Group 4: Industry Context - Pneumococcal disease remains a significant health threat, particularly in children under five, with Streptococcus pneumoniae being a leading cause of vaccine-preventable deaths globally [14][15] - The development of broader-spectrum vaccines like VAX-24 and VAX-31 is critical to addressing the substantial burden of invasive pneumococcal disease [6][14]