A Clinical Study to Evaluate the Safety, Tolerability, and Immunogenicity of VAX-31 With Influenz… (NCT07365826) | Clinical Trial Compass
Active — Not RecruitingPhase 3
A Clinical Study to Evaluate the Safety, Tolerability, and Immunogenicity of VAX-31 With Influenza Vaccine in Adults ≥ 50 Years of Age
United States1,390 participantsStarted 2026-01-12
Plain-language summary
This is a Phase 3, randomized, double-blind study to evaluate the safety and immunogenicity of VAX-31 and seasonal influenza vaccine in pneumococcal-naïve adults ≥ 50 years when the two vaccines are administered at the same visit or separately.
Who can participate
Age range
50 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Male or female ≥50 years of age (inclusive) at the time of randomization into the study.
. Able and willing to complete the informed consent process.
. Available for clinical follow-up through the last study visit at 7 months after the first study vaccination.
. In good general health or with stable underlying chronic condition(s), as determined by medical history, oral temperature, physical examination, and clinical judgment of the Investigator.
. Willing to have blood samples collected and used for research purposes.
. Able to provide proof of identity to the satisfaction of the study site personnel completing the enrollment process.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1This trial is comparing giving VAX-31 and the flu shot at the same time versus one month apart — given my personal health situation, is there any reason my doctor would recommend one approach over the other, or would either schedule work for me?
2The trial is measuring immune responses across 31 pneumococcal serotypes plus serotype 20B — how does the breadth of VAX-31 compare to the pneumococcal vaccines I may have already received, and could my prior vaccination history affect whether this trial is even relevant to me?
3Since this is a Phase 3 trial that is no longer enrolling, the safety data being collected — including injection site reactions, fever, fatigue, and muscle pain — will likely become publicly available soon; is there any way to review those early findings before deciding whether VAX-31 is something I should consider in the future?
4The trial is tracking serious adverse events and other significant health events for up to 6 months after the last vaccination — what does that level of follow-up monitoring tell us about what researchers still need to learn about this vaccine's safety profile?
5Are there already approved pneumococcal vaccines that cover a similar or overlapping range of serotypes that I could discuss as a standard-of-care option right now, rather than waiting for VAX-31 to potentially become available?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
For each of the 32 serotypes (the 31 serotypes included in VAX-31, and serotype 20B), the ratio (co-administration group to sequential administration group) of opsonophagocytic activity (OPA) geometric mean titers (GMT) in evaluable participants
Timeframe: 1 Month after VAX-31 vaccination
2
For each of the strains in SIV, the ratio (co-administration group to sequential administration group) of hemagglutination inhibition (HAI) GMT in evaluable participants
Timeframe: 1 Month after SIV administration
3
Percentage of participants reporting solicited local adverse events (AE) within 7 days after Day 1 and Month 1 vaccination (redness, swelling, and pain at injection site) in each group
Timeframe: 7 days after each vaccination
4
Percentage of participants reporting solicited systemic AE within 7 days after Day 1 and Month 1 vaccination (fever, headache, fatigue, muscle pain, and joint pain) in each group
Timeframe: 7 days after each vaccination
5
Percentage of participants reporting unsolicited AE within 1 month after Day 1 and Month 1 vaccination in each group
. Female subjects of childbearing potential, defined as premenopausal females capable of becoming pregnant, must have a negative urine pregnancy test at Screening and immediately prior to each vaccination and agree to use acceptable contraception, if heterosexually active. Female subjects who are not abstinent from heterosexual intercourse must agree to consistently practice contraception at least 7 days prior to vaccination and through their last study visit. Male subjects with partners of childbearing potential must agree to practice an acceptable contraception method (\[use condoms with or without spermicide\] or have undergone a vasectomy) from Day 1 through their last study visit. Note: A history of amenorrhea for at least 12 months without an alternative medical cause is required for a female to be considered postmenopausal in the study.
. Able to access and use a device connected to Wi-Fi or cellular network for completion of an electronic diary (eDiary).
Exclusion criteria
. History of IPD or pneumococcal pneumonia (either confirmed or self-reported) at any age.
. Previous receipt of a licensed or investigational pneumococcal vaccine at any age.
. Previous receipt of an influenza vaccine from the current season; receipt of any influenza vaccine (licensed or investigational) within 6 months prior to Day 1; or receipt/planned receipt of any licensed or investigational non-study influenza vaccine during study participation.
. Receipt of any investigational product within 30 days prior to Day 1, currently participating in another interventional investigational study, or having plans to receive another investigational product(s) while on study.
. Planned or actual administration of any licensed vaccine within 30 days prior to Day 1.
. Body temperature \>38.0°C (\>100.4°F) or acute illness within 3 days prior to study vaccination (participant may be rescreened).
. Current diagnosis of human immunodeficiency virus (HIV), Hepatitis B, or Hepatitis C.
. History of severe allergic reaction with generalized urticaria, angioedema, or anaphylaxis to any previous vaccination.
Percentage of participants reporting NOCI, MAAE, and SAE within 6 months after last vaccination in each group