Trial results

$PCVX — VAX-31

Vaxcyte, Inc. (PCVX) VAX-31: trial results in adult pneumococcal disease, 2026.

Research by Catalyst Intel · Published 2026-09-13 16:57 ET · Updated 2026-10-05 21:45 ET

The catalyst

"The Company also announced that topline safety, tolerability and immunogenicity data from the VAX-31 adult Phase 3 OPUS-1 trial are now expected by the end of October, narrowing its previously communicated guidance of disclosing topline trial data in the fourth quarter of this year."

— Vaxcyte, Inc., 8-K filed 2026-09-03 · the filing. Checked word for word against the stored document when this page was built; a sentence that did not check out would not be here.

Event id

PCVX-VAX31-2026

Company

Vaxcyte, Inc.

Kind

Trial results

Indication

adult pneumococcal disease

Window

2026-10-01 – 2026-10-31

Status

bar_published

The bar

Published 2026-09-13 16:57 ET, before the event. The text below is the hashed text: paste it into the verify page and your browser will recompute the same digest.

EVENT PCVX-VAX31-2026
SCORED SET evaluable
FLOOR floor_opa_ni_margin Lower bound of the 2-sided 95% CI of the OPA geometric mean ratio versus PCV20 greater than 0.5 for shared serotypes (the company's printed non-inferiority criterion).
FLOOR floor_shared_st_ni_count All 20 serotypes common with PCV20 meet OPA non-inferiority, matching VAX-31 high-dose Phase 1/2.
BAR bar_shared_gmr_gt1_count At least 18 of 20 shared serotypes with OPA GMR greater than 1.0 versus PCV20, matching VAX-31 high-dose Phase 1/2.
BAR bar_unique_st_superiority_count All 11 serotypes unique to VAX-31 and not in PCV20 meet superiority criteria, matching every dose in Phase 1/2.
BAR bar_unique_st_gmr_lb Lower bound of the 2-sided 95% CI of the OPA GMR for each unique serotype greater than 2.0 (printed superiority criterion).
BAR bar_unique_st_4fold_lb Lower bound of the 2-sided 95% CI of the difference in the proportion of participants with a ≥4-fold OPA increase from Day 1 to Month 1 greater than 10 (printed superiority criterion, percent).
DIFF diff_shared_stat_higher_gmr Lower bound of the 2-sided 95% CI of the OPA GMR versus PCV20 greater than 1.0 on shared serotypes (the company's printed statistically higher bar).

SHA-256

7497f8b0abfee8cac8baf9d1906706d0333c82f8ba7aca36298bc84c8ac5c0e1

Frozen

yes

Public post

https://x.com/i/web/status/2099241029870223651

Criteria as committed

Floor — all must pass

Bar — all must pass

Differentiators — one upgrades IN_LINE to BEAT

What we could not source before the event

• No document names the OPUS-1 analysis population (ITT, mITT, FAS, PP, evaluable); scored_set is null.
• No CT.gov record in the packet; primary_outcome cannot be copied from protocolSection.outcomesModule.primaryOutcomes[].measure.
• No Phase 3 protocol, SAP, or FDA minutes restate the OPUS-1 non-inferiority margin, alpha, or success criterion; 0.5 / 1.0 / 2.0 / 10 are Phase 1/2 definitions.
• No VAX-31 versus PCV21 OPA GMR, NI margin, or superiority rule.
• No serotype-level OPA GMR point estimates as printed digits (Phase 1/2 gave counts only).
• No numeric SAE, TEAE, or solicited-AE rates for VAX-31 adult Phase 1/2.
• Statistically higher serotype counts are spelled (seven / five / three) and were not used as values.
• manual/comparators.md and manual/options_snapshot.md are empty placeholders.
• analysis population: safety — prior_topline_pr_3 states the primary result's population: safety ("Global Pneumococcal Vaccine Market March 31, 2025 39 39 Billions Pipeline of High-Fidelity Vaccines Broad-Spectrum Conjugate and Novel Protein Vaccines to Prevent or Treat Bacterial Infectious Diseases Preclinical Phase 1 Phase 2 Phase 3 Adults 50+ 31-Valent VAX-31 Infants PCV Candidate 24-Valent VAX-24 Infants PCV Candidate VAX-XL Adults & Infants VAX-XL PCV Candidate Novel Group A Adults & Infan"); change it in the editor if the protocol says otherwise

Verdicts