The purpose of this research study is to evaluate the safety of and the body's immune response to single and multiple vaccinations in healthy men and women. We want to find out what effects GBP511 has on you and your health. We are doing this study to find out: If the study drug has any side effects when given as single and multiple vaccinations. If reactogenicity, an indication that the immune systems is working and is preparing to protect the body against future infection, occurs. This is a normal physical inflammatory response that occurs after vaccination, manifesting as localised reactions that may include pain or redness at the injection site, or systemic symptoms such as headache or fever. If immunogenicity which is when GBP511 causes your body to make antibodies against the non-harmful viral proteins contained within GBP511, called 'neutralising antibodies (Nab),' occurs. And if GBP511 will cause the specialised cells of the body's immune system to mount a defence against the non-harmful viral proteins contained within GBP511, called 'cell-mediated immunity (CMI)'. In this study, GBP511 will be administered with and without adjuvant, CAS-1. An adjuvant is an ingredient used in some vaccines that help produce a stronger immune response in the people receiving the vaccine and thus helps the vaccine work better. This study will recruit approximately 368 participants in total and will be conducted in two stages: Stage 1 will look at two vaccinations with GBP511 when given with and without the CAS-1 adjuvant; and Stage 2 will look at either one or two vaccinations with two candidate GBP511 vaccines chosen from Stage 1 of the study. Participants will be required to attend Linear's clinical unit on two separate occasions to receive their two vaccinations. On the first day of dosing (Visit 2/Day 1) and second day of dosing (Visit 5/Day 29), we will be testing a single dose of the study drug in up to 168 healthy volunteers who will be divided into 3 groups. Group 1, Groups 2 and 3 will have 56 people each. These 3 groups will be divided into treatment subgroups, with a total of 6 test subgroups and 3 control subgroups. In all groups, neither you or the study doctor will know what subgroup you are part of, and therefore what treatment (GBP511 or Comirnaty+ placebo) you will receive.
Age range
18 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.
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.
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
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.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Percentage of participants experiencing any immediate reactions
Timeframe: 30 minutes (2 hours for sentinel participants) following each study vaccination
Percentage of participants reporting any solicited local AEs
Timeframe: during the 7 days following each study vaccination
Percentage of participants reporting any solicited systemic AEs
Timeframe: during the 7 days following each study vaccination
Percentage of participants experiencing any unsolicited AEs
Timeframe: during the 28 days following each study vaccination
Percentage of participants experiencing any SAEs, MAAEs, AESIs, as well as AE leading to study withdrawal
Timeframe: 1st Vaccination date, 1 week, 2 weeks, 4 weeks following the 1st study vaccination, and 2nd vaccination date, 1 week, 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the 2nd study vaccination.
GMT of neutralizing antibody against each matched strain measured by a pseudo-virus neutralization assay at each time point.
Timeframe: At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the last study vaccination.
GMR of neutralizing antibody against each matched strain measured by a pseudo-virus neutralization assay, from each pre-vaccination to subsequent time point.
Timeframe: At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the last study vaccination.
Percentage of participants with ≥ 2-fold and 4-fold rises against each matched strain in pseudo-virus neutralizing antibody titer, from baseline to each subsequent time point
Timeframe: At baseline, 2 weeks, 4 weeks following the 1st study vaccination, and 2 weeks, 4 weeks, 3 months, 6 months, and 12 months following the last study vaccination.