Vaxcyte (NASDAQ:PCVX) executives used the company’s fourth-quarter and full-year 2025 earnings call to highlight progress in late-stage development of its pneumococcal conjugate vaccine (PCV) franchise, expand on plans to restart development of its Group A Strep program, and outline a strengthened balance sheet following a recent equity raise.
Focus on VAX-31 as the PCV market expands
Chief Executive Officer Grant Pickering said pneumococcal disease continues to cause substantial morbidity and mortality globally, and argued that “gaps in serotype coverage persist” despite existing vaccines. He pointed to “accelerating growth in the adult PCV market,” driven by expanded U.S. recommendations and growing international adoption, and said momentum in the category reinforces demand for a broader-coverage vaccine while maintaining strong immune responses.
OPUS Phase 3 adult program: timing and design details
Executive Vice President and Chief Operating Officer Jim Wassil said the Phase 3 OPUS program was finalized “in consultation and alignment with the FDA” and is intended to support a planned biologics license application (BLA). The OPUS studies are designed to generate a broad safety, tolerability, and immunogenicity data set across adult populations and real-world vaccination scenarios.
- OPUS-1: A pivotal non-inferiority trial in adults aged 50 and older, comparing VAX-31 head-to-head versus Prevnar 20 (PCV20) and Capvaxive/“Quadaxix” (PCV21). Management said top-line safety, tolerability, and immunogenicity data are expected in Q4 2026.
- OPUS-2: A Phase 3 study evaluating VAX-31 when administered concurrently with, or one month after, a licensed high-dose seasonal influenza vaccine. Management said readout is expected in the first half of 2027.
- OPUS-3: A Phase 3 study in adults previously vaccinated with lower-valency pneumococcal vaccines, intended to evaluate safety and immune responses and potentially support a “catch-up” recommendation. Management also guided to a first-half 2027 readout.
Wassil said OPUS-1, -2, and -3, along with a planned manufacturing consistency study, are designed to support the BLA. Across the three trials, the company expects to enroll approximately 6,000 adults, with about 3,400 receiving VAX-31.
In response to investor questions on OPUS-1 powering and statistical requirements, Pickering said the pivotal trial was “locked down” with the FDA and that Vaxcyte has strong data to inform powering versus PCV20 from prior head-to-head work. For the 10 serotypes common to VAX-31, PCV20, and PCV21, he said the analysis plan requires Vaxcyte to demonstrate non-inferiority to “one or the other” comparator to declare success. He also emphasized that regulators evaluate vaccines based on the “totality” of the data package and public health impact, and said the company believes it has “headroom” given the incremental serotype coverage.
Asked specifically about serotype 3, Pickering described it as a persistent outlier in the category and said it has not proven to be a meaningful differentiator among marketed vaccines because none have generated antibody responses seen as sufficient to control it. He added that Vaxcyte’s serotype 3 responses were better than PCV20 in its earlier adult and infant studies, but said the company does not expect serotype 3 to be a competitive differentiator.
Management also addressed post-marketing expectations, stating the company’s approach is consistent with agreements used for currently marketed PCVs, including a test-negative design surveillance approach used to monitor pneumonia cases in the environment.
Infant program update: VAX-24 learnings applied to VAX-31 Phase 2
Pickering said Vaxcyte reported final data from the VAX-24 Phase 2 dose-finding study in infants in November, and described the results as consistent with positive interim findings. He said the data provided insights into immune responses, concomitant administration with other vaccines, and dose responsiveness.
Wassil said those learnings led Vaxcyte to modify its ongoing VAX-31 infant Phase 2 study to include an optimized dose arm evaluating higher doses. Enrollment is complete, with 900 infants dosed. The company expects to announce top-line safety, tolerability, and immunogenicity data for both the primary three-dose series and booster dose “either sequentially or together” by the end of the first half of 2027.
Chief Financial Officer Andrew Guggenhime said the company is evaluating whether unblinding and disclosing the primary series (PD3) data earlier could provide operating benefits—such as enabling earlier FDA engagement for an end-of-Phase 2 meeting or allowing Phase 3 initiation sooner. Vaxcyte expects an update on its unblinding and disclosure plans by mid-2026.
Manufacturing build-out, commercialization preparation, and financial runway
On manufacturing, Pickering said Vaxcyte completed construction of a dedicated large-scale manufacturing facility “on time and on budget,” designed to support global commercial demand in developed markets. He also said construction is underway for a high-volume, custom fill-finish production line in North Carolina as part of a long-term investment of up to $1 billion in U.S. manufacturing and services.
Commercially, Pickering said the company has begun scaling the organization, including hiring its first Chief Commercial Officer, Mike Miletich, and starting launch planning. During Q&A, Miletich said the company is seeing early signals in the 50–64 age segment following the expanded U.S. recommendation, while noting that immunizations in that group may have been lower in the year due to lower influenza vaccination rates in Q4. He also said Capvaxive’s market share gains support the dynamic of the market shifting toward higher-valency vaccines, and pointed to increasing adult vaccination adoption internationally in Europe, Japan, and Canada.
Financially, Guggenhime said Vaxcyte ended 2025 with $2.4 billion in cash, cash equivalents, and investments. After year-end, the company completed a public equity offering generating approximately $600.2 million in net proceeds. Including those proceeds, he said Vaxcyte expects cash runway to “at least the end of 2028.”
He also forecast that 2026 total expenses—particularly R&D—will increase meaningfully versus 2025, driven by manufacturing spend to support commercial readiness (including building VAX-31 commercial supply ahead of a potential launch) and higher clinical spending from a greater number and size of trials. Guggenhime added that capitalized costs are expected to trend down in 2026 because the dedicated manufacturing facility build-out is complete and related costs will shift from capitalized to expensed.
Group A Strep program VAX-A1 set to restart in 2026
Beyond PCV, management said the company will resume development of its most advanced preclinical non-PCV program, VAX-A1, a Group A Strep vaccine candidate. Wassil said Vaxcyte expects to initiate a Phase 1 adult study in 2026, focused primarily on safety and tolerability, and plans to conduct the study in Australia. He said the trial will also assess immunogenicity (including IgA and IgG in serum and saliva), but noted there is “no correlate of protection.” He also outlined a development concept that could include moving into toddlers and pursuing a smaller proof-of-concept study given the ubiquity of strep throat in children.
Guggenhime said the earlier decision to pause pipeline programs—including VAX-A1—was driven principally by financial considerations, and that the February financing helped enable the company to restart the program while maintaining resources to execute PCV milestones.
About Vaxcyte (NASDAQ:PCVX)
Vaxcyte, Inc (NASDAQ: PCVX) is a clinical-stage biotechnology company focused on developing a new generation of preventive vaccines aimed at combating serious bacterial diseases. Headquartered in San Carlos, California, Vaxcyte leverages proprietary conjugation technologies to design and manufacture multivalent vaccines targeting pathogens for which there remain significant unmet medical needs. The company’s platform is intended to streamline the production of conjugate vaccines by improving antigen presentation and broadening strain coverage compared with conventional approaches.
Vaxcyte’s lead candidate, VAX-24, is a 24-valent pneumococcal conjugate vaccine designed to protect against 24 serotypes of Streptococcus pneumoniae.
