Vaxcyte (PCVX) investor relations material

Regulatory and FDA engagement

• Ongoing parallel efforts with government/public affairs and direct FDA interactions to advance vaccine programs.

• Phase III adult non-inferiority study for the 31-valent vaccine set to initiate in December, with protocol and FDA feedback in place.

• Recent FDA memo aligns with current development plans; no changes required for adult or infant programs.

• Post-marketing studies for pneumonia are standard and already planned; no new efficacy or placebo-controlled requirements from FDA.

• Infant vaccine regulatory focus remains, but major discussions with FDA will occur after phase II, likely in a few years.

Clinical development and study design

• Adult phase III program to start in December, with key data readouts expected in 2026 and potential BLA submission in 2027.

• Infant 31-valent phase II study ongoing, with booster data expected by mid-2027 and phase III to follow.

• Dose optimization in phase II aims to improve immunogenicity, especially for lower-performing serotypes.

• Higher doses and an optimized dosing arm added to the 31-valent study to enhance response rates.

• Phase III infant studies will be larger, with at least 800 patients per arm, to ensure robust serological endpoints.

Scientific and public health insights

• Otitis media outcome studies in infants are feasible and may support label claims without requiring pneumonia outcome studies.

• Demonstrating reduction in all-cause otitis media could have significant public health and economic benefits.

• Maintaining high immunogenicity is critical to prevent serotype reemergence, as seen in international examples.

• Unique serotypes in the 31-valent vaccine cover a significant portion of disease burden, with dose adjustments expected to improve results.

• Confidence remains high that higher doses will reduce the number of missed serotype responses in future studies.