What is the purpose of this trial?

The purpose of this study is to test a new COVID-19 vaccine to determine if it is safe and works to stimulate an immune response that may prevent COVID-19 disease.


COVID-19 is a new, contagious disease that has quickly infected many people all over the world. The symptoms usually include fever, cough, and shortness of breath lasting several days to 2 or more weeks. COVID-19 may sometimes cause severe illness such as pneumonia (lung infection) and serious trouble breathing, which can lead to a hospitalization and may possibly cause death.


Older adults and people with long-term health problems, especially of the lungs and heart, are at higher risk of having complications compared to young, healthy children and adults.


Vaccines are the most efficient way of controlling outbreaks and many companies are working to develop vaccines against COVID-19.


The COVID-19 vaccines in this study are either monovalent (containing the spike protein antigen from 1 variant [variant means type of coronavirus]) or bivalent (containing the spike protein antigen from 2 variants). There will be 2 monovalent vaccines and one bivalent vaccine in this study. The monovalent vaccines will contain either the D614 strain (original Wuhan strain) or the B.1.351 strain (Beta variant). The bivalent vaccine includes both the D614 and B.1.351 strains.


The purpose of this study is to determine if these investigational COVID-19 vaccines are safe and can stimulate and broaden the immune response against the different COVID-19 variants that cause COVID-19 when given as a single booster injection in participants who have previously been vaccinated with a full course of an authorized COVID-19 vaccine.

      Am I eligible to participate?

      This study is planned to include participants who are 18 years of age and older and have previously been vaccinated against COVID-19. A broad range of people may be included, from those who are healthy to those with health problems that put them at risk for complications due to COVID-19. It is also designed to include older adults and from ethnic and racial minorities.

      If you have already received a booster (or a 3rd dose) of COVID-19 vaccine, you cannot participate in this study.

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      What’s next?

      Please read the full participant information sheet, then complete the questionnaire to determine if you are eligible to participate.


          What does this study involve?

           In this study, we will enroll up to 3,145 volunteers who have previously completed a COVID-19 vaccine course (either two or one dose as appropriate) between 4 to 10 months previously, in several different countries.

          If consented and enrolled, participants will:
          • Receive one injection of investigational vaccine
          • Complete six visits over a period of approximately 12 months. Additional visits can also occur if you develop symptoms of COVID-19.
          All participants will receive an investigational vaccine; there is no placebo group (no one will get an injection identical to the vaccine with no active ingredients). All injections will be given into the muscle of your upper arm.  Depending on the group you are assigned to, you may or may not know which version of the vaccine you received.

          At the first visit, a swab from the back of your nose will be collected to test for COVID-19. During the study, blood samples will be collected to see how your body responds to the investigational vaccine. If you develop symptoms that suggest you may have COVID-19, additional swabs will be collected and tested. Additional blood samples and saliva samples will be taken from some participants to evaluate the immune response after vaccination in more detail.

          What are the advantages of taking part?

          You may or may not benefit from participating in this study. However, your participation will contribute to helping us learn more in the search for another safe and effective COVID-19 vaccine.

          Are there any risks from taking part in the study?

          There are risks of side effects that might occur with the use of investigational vaccines. Some risks and side effects may still be unknown at this stage. The study staff are trained to take the right measures to minimize risks and limit any discomfort you may experience.

          The known risks and side effects of the proposed study procedures are:

          • Blood samples: You may have pain, tenderness or bruising at the place where blood was drawn. Fainting or feeling dizzy can occur after a blood draw, but this is uncommon.
          • Vaccinations: Some side effects may be seen with this investigational vaccine include pain, redness, swelling and tenderness at the site of injection. You may also experience headache, muscle aches, generally feeling ill, fever and chills. These are usually mild to moderate and should not prevent you from doing your usual activities. They usually go away within 2-4 days after injection.

          As with any vaccination, there is a possibility of an allergic reaction, such as a rash, swelling of the lips or face, or difficulty breathing. If such a reaction occurs, it is usually almost immediately after the injection. Therefore, you are required to remain at the study site for 30 minutes after vaccination to ensure medical attention is available, if needed.

          Please refer to the participant information sheet for full details of procedures and potential risks.

          What will happen if I don’t want to join or carry on with the study?

          Participation in this study is voluntary. You may choose to not participate, or you may withdraw from the study for any reason without penalty or loss of benefits to which you are otherwise entitled and without any effect on your future medical care.

          If you wish to end your participation in the study, please tell us. If you leave the study for any reason, we may recommend that you come back for certain tests or examinations to check on your health.

          MAT-GB-2103998(v3.0)   Date of preparation: January 2022