Vaxcyte executives outlined development, data and commercialization plans for its lead pneumococcal vaccine and Group A strep candidate during a session at the Wells Fargo 21st Annual Healthcare Conference on Tuesday, September 8, 2026. At the time of the transcript, Vaxcyte shares were quoted at $60.48, down 1.11% from the previous close of $61.16, with a 52-week range of $30.81 to $65.00 and a current ratio of 5.72.
VAX-31, the company's 31-valent pneumococcal conjugate vaccine, is the lead program. Executives said it covers about 95% of circulating pneumococcal strains, compared with about 60% for Pfizer's Prevnar 20 and about 82%, or 80% to 85%, for Merck's CAPVAXIVE, also referred to as PCV21. Vaxcyte's Phase II data showed average immune responses that were 25% higher than Prevnar 20, while broader-spectrum vaccines have historically been associated with about a 25% lower response. CEO Grant Pickering described the company as a vaccine platform built around cell-free protein synthesis and site-specific conjugation, which he said allows expanded conjugate-vaccine coverage without the usual decline in immune response.
The pivotal OPUS-1 Phase III study will use a 1:1:1 randomization design with approximately 1,200 subjects per arm and will compare VAX-31 with Prevnar 20 and CAPVAXIVE. The study includes 11 serotypes found in all three products, 9 serotypes found in Prevnar 20 and VAX-31 only, and 8 serotypes found in CAPVAXIVE and VAX-31 only, in addition to unique serotypes. Vaxcyte expects to miss on one serotype comparison versus Prevnar 20 and up to five misses versus CAPVAXIVE in its base case. OPUS-1 pivotal data are expected by the end of October 2024, with a technical chance of an earlier September readout, while OPUS-2 and OPUS-3 data are expected in the first half of 2025. A manufacturing consistency study is expected to begin in 2027, and the company is targeting BLA approval by the end of 2028 with Breakthrough Therapy Designation.
Management also discussed the competitive and regulatory environment. Prevnar 20 reached about 98% market share over Merck's 15-valent predecessor despite launching later. Pickering said CAPVAXIVE's label states that the vaccine is not to be used in the Western United States, where serotype 4 is circulating aggressively. The discussion referenced the U.S. FDA, ACIP, AMA and the Vaccine Integrity Project, and noted that the first pneumococcal conjugate vaccines were approved 25 years ago, with adult pneumococcal vaccination gaining traction about 15 years ago.
VAX-A1, Vaxcyte's Group A strep vaccine candidate, is expected to report Phase I data in the second half of 2025. Pickering said the candidate offers two ways to win because both the protein carrier and the universal carbohydrate can generate antibodies that clear the bacterium. The company cited 900,000 deaths a year globally from heart-damage sequelae, $5 billion per year in U.S. healthcare spending tied to childcare and strep throat management, and a school-aged children attack rate of 15% to 20%, which it described as 6 to 7 times higher than the attack rate of RSV.
CFO Andrew Guggenhime said an approved Vaxcyte 1 would be best-in-class by definition because of its broader serotype coverage profile. Pickering characterized pneumococcal disease as a clear and present danger, noting that community-acquired pneumonia, meningitis and invasive pneumococcal disease remain common public health threats. The session included Wells Fargo analyst Yanan Zhu and referenced the broader vaccine industry, including Pfizer, Merck, AstraZeneca, Sanofi, Eli Lilly and Moderna.
