A Phase 1/2A, Randomized Study of a T Follicular Helper (TFH)-Targeting Genetic Vaccine Strategy … (NCT06810934) | Clinical Trial Compass
RecruitingPhase 1/2
A Phase 1/2A, Randomized Study of a T Follicular Helper (TFH)-Targeting Genetic Vaccine Strategy Designed to Induce Broad, Durable Immune Responses
United States80 participantsStarted 2025-10-21
Plain-language summary
The goal of this clinical trial is to test two investigational COVID-19 booster vaccines, called CoTend-s3BXBB and CoTend-BXBB, in healthy volunteers ages 40-64. The CoTend-s3BXBB vaccine includes a component called "s3", which was designed to improve the body's response to the vaccine. CoTend-BXBB is the same vaccine without s3.
The main questions the study aims to answer are: 1) Is the investigational vaccine safe? 2) Does "s3" lead to bigger, broader, and longer-lasting responses to the vaccine?
5 different doses of the vaccines will be studied. Participants will receive a single dose of either CoTend-s3BXBB, CoTend-BXBB, or placebo. Participants will be monitored for side effects. Saliva, nasal, and blood samples will be collected and immune responses to the vaccine will be measured.
Who can participate
Age range
40 Years – 64 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
. Individuals 40 - 64 years of age
. Received at least two doses of a COVID-19 mRNA vaccine (Moderna or Pfizer) \> 120 days before study entry
. Nasal SARS-CoV-2 negative by molecular (polymerase chain reaction, PCR) testing at screening
. The following laboratory criteria must be met at screening:
. Total white blood cell (WBC) count \> 3500 cells/mm3
. Hemoglobin \> 13.5 g/dL if male sex and \> 12.0 g/dL if female sex
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.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
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
Frequency of solicited local reactogenicity adverse events (AEs) within 7 days after dosing.
Timeframe: 7 days
2
Frequency of solicited systemic reactogenicity AEs within 7 days after dosing.
Timeframe: 7 days
3
Frequency of unsolicited AEs within 28 days after dosing.
Timeframe: 28 days
4
Frequency of serious adverse events (SAEs) within 28 days after dosing.
Timeframe: 28 days
5
Frequency of adverse events of special interest (AESIs) within 28 days after dosing.
Timeframe: 28 days
6
Frequency of medically attended adverse events (MAAEs) within 28 days after dosing.
Timeframe: 28 days
7
Geometric mean titers (GMTs) of serum anti-XBB.1.5 neutralizing antibodies (NAb) through week 8.
. For participants capable of becoming pregnant and engaging in sexual activity that can lead to pregnancy, unwillingness to use contraception during participation in the study. For participants capable of becoming pregnant, two of the following forms of contraception are required through 30 days following administration of study intervention, one of which must be a barrier method:
. Condoms (male or female) with or without a spermicidal agent
. Diaphragm or cervical cap with spermicide
. Intrauterine device (IUD)
. Hormone-based contraceptive such as oral birth control pills
. Known close contact with anyone with confirmed SARS-CoV-2 infection (defined as positive SARS-CoV-2 nucleic acid or antigen testing by laboratory-based or home self-test) within 2 weeks prior to expected study entry
8
Proportion of participants achieving serum anti-XBB.1.5 NAb titers of 1:250 or better through week 8.
Timeframe: 8 weeks
9
Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-XBB.1.5 NAb responses.