Pfizer’s $6.49 Billion Prevnar Franchise Faces a New Challenger
Vaxcyte's VAX-31 vaccine met primary endpoints in a Phase 3 trial, matching Pfizer's Prevnar 20 and Merck's Capvaxive on most serotypes. Prevnar generated $6.49B in 2025, about 10% of Pfizer's revenue, while Capvaxive brought in $759M. VAX-31's approval is not expected until 2028, with Pfizer having more at stake due to its larger franchise.
How this was made
The 30-second read
Why it matters
The trial results introduce a new competitive threat that could affect future sales forecasts for both incumbents while providing a growth catalyst for Vaxcyte.
Market read
New Phase 3 data could shift investor sentiment on the three companies, especially impacting Pfizer and Merck's vaccine revenue outlook.
What to watch
Insurance reimbursement policies and existing contracts could mitigate immediate impact.
Background
Pfizer and Merck rely on multi-valent pneumococcal vaccines for a significant portion of their revenue. Vaxcyte, a biotech, is developing a 31-valent vaccine.
Ticker impact
Vaxcyte's VAX-31 trial showed comparable efficacy to Pfizer's Prevnar 20, posing a competitive threat to Pfizer's $6.49B vaccine franchise.
likely downside as market prices in competitive risk
Trial data is fresh and directly challenges a major revenue source.
VAX-31 also outperformed Merck's Capvaxive on most shared serotypes, increasing competitive risk for Merck's pneumococcal vaccine.
potential pressure on stock as investors reassess growth outlook
New trial results highlight Merck's smaller market exposure and competitive disadvantage.
Vaxcyte announced its Phase 3 trial met all primary endpoints, positioning VAX-31 for FDA filing in H1 2028.
likely upside as investors price in future market entry
First report of successful pivotal trial provides material new information.
Market effects
May reshape competitive dynamics in the pneumococcal vaccine market.
US adult vaccine market could see pricing pressure.
Potential ripple effects for global vaccine manufacturers.
Counterpoint
If VAX-31 faces regulatory delays, Pfizer and Merck may retain market share longer.
Key entities
- CompanyPfizer Inc.
Manufacturer of Prevnar 20, a leading pneumococcal vaccine.
- CompanyMerck & Co.
Producer of Capvaxive, a newer pneumococcal vaccine.
- CompanyVaxcyte Inc.
Biotech developing the 31-valent VAX-31 vaccine.
