- Comparing COVID-19 Vaccine Study for over 50s

Comparing COVID-19 Vaccine Study for over 50s

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Comparing COVID-19 Vaccine Study for over 50s

at Guy's and St Thomas' NHS Foundation Trust

Participate - Guy's and St Thomas' NHS Foundation Trust

Comparing COVID-19 Vaccine Schedule Combinations – Com-COV

The Guy's and St Thomas' NHS Foundation Trust site is recruiting participants from the London area :

What is the purpose of this research study?

There are now a number of vaccines in the UK that have been approved to prevent COVID-19, and others are expected to be approved in the near future. These use two-doses, a ‘prime’ first dose, followed by a ‘boost’ second dose some weeks later. The purpose of this trial is to see how well people’s immune systems respond when their second “boost” dose is a different type of vaccine to their first “prime” dose. We will also be looking at how common vaccine reactions, such as fever, are after such ‘mixed’ schedules. This is important, as being able to use different vaccines in this way creates a more flexible immunisation programme; potentially allowing more people to be immunised more quickly.

In this study we will be enrolling men and women aged 50 years and over who have already had one dose of a COVID-19 vaccine. We are enrolling from all ethnicities and would particularly welcome participants from the Black, Asian and Minority Ethnic (BAME) community.

click here to read more information

What are the vaccines against?

These vaccines are against the coronavirus SARS-CoV2 that causes the disease COVID-19.

Common symptoms of COVID-19 include fever, tiredness, dry cough, and changes to taste and smell. Whilst about 80% of infected people have no or mild symptoms and will recover from the infection without needing special treatment, approximately 10-15% of cases (2-3 in 20) progress to develop severe symptoms, and about 5% (1 in 20) become critically ill.

There are some treatments that have been shown to be effective in reducing the severity of disease and the risk of death; but at present, there is no cure. Older people and those with underlying medical conditions are more likely to develop serious illness. It has also been seen that people of some ethnic groups (Black and Asian) might be at a greater risk of severe illness. More than 2.7 million people globally have died from COVID-19 as of 22nd March 2021. Some people also have symptoms that last a long time after they have recovered from the acute infection (commonly referred to as “long-COVID”). Effective vaccines can prevent infection in the first place, which is why they are so important.

Am I suitable to take part?

Adults that are aged 50 and over are able to take part. In order to be enrolled in the trial:

  • You must have had your first dose of COVID-19 vaccine through the national immunisation programme between 25th January 2021 and 20th March 2021

  • Be able to provide documentation of this to the trial team, or allow the trial team to check this information via NHS systems

  • You must be willing to tell the trial staff about your medical history, and you may be asked to allow the trial staff to check this with your General Practitioner (GP). Bear in mind that we would also notify your GP if you joined the trial (even if we did we not need to check your medical history with them in advance).

  • If you are able to become pregnant you must be willing to practice continuous effective contraception during the trial and have negative pregnancy tests on the days of vaccination

  • You must agree not to donate blood during the trial

For further details on why you could not take part in this study please see the Participant Information Sheet.
Summary of the study

In this study participants will receive a second dose of a COVID-19 vaccine that may differ from their first dose received through the national immunisation programme. We are aiming to recruit 1050 participants. As new SARS-CoV-2 vaccines become available, more vaccines may be included in the trial and so the total number of participants may increase.

  • Participants must be 50 years and over, and have had one dose of a COVID-19 vaccine through the national immunisation programme approximately 8 to 12 weeks before being enrolled in the study. They cannot have received their boost dose already.

  • Participants will be allocated, at random, to receive the same vaccine as their first dose “prime”, or one of two different COVID-19 vaccines.

  • They will not know which vaccine they have received for their boost (i.e. they will be “blinded”)

  • Between 5 and 7 routine blood tests will be taken over 10 months to look at the immune responses to the vaccine depending on the group you are in. You may also be asked for a nasal fluid and saliva sample at each visit. You might also be asked to attend for a repeat blood test if there were any safety concerns.

  • Participants will need to complete an online diary for up to 28 days following the vaccine received in the trial

  • Participants should expect their involvement in the trial to last approximately 10 months

  • We would not be offering diagnostic COVID-19 testing as part of this trial, but it is important that participants in this trial access COVID-19 testing outside of the trial following normal government guidance.

  • If you were to test positive for the virus causing COVID-19 we may ask you to attend for an extra visit.

Once you have received your vaccine through the trial, unless specifically advised by us, you would not be eligible to receive any further vaccine dose via the government vaccination scheme. This will be reviewed if government guidance changes.

What vaccines are being used in this study?

At present, the vaccines in this trial are:

  • Oxford/AstraZeneca ChAdOx1 nCoV-19 (hereafter referred to as AstraZeneca)

  • Pfizer/BioNTech BNT162b2 (hereafter referred to as Pfizer)

  • COVID-19 Vaccine Moderna (hereafter referred to as Moderna)

  • Novavax NVX-CoV2373 (hereafter referred to as Novavax)

Pfizer, Moderna, and AstraZeneca vaccines have been approved for emergency use in the UK under regulation 174 of the Human Medicines Regulations 2012.

The vaccine Novavax has been tested in clinical trials that have enrolled over 45 000 people, and has been shown to be highly effective at preventing COVID-19. This vaccine has not yet been approved for use by the UK Medicines Healthcare Regulatory Agency (MHRA), but this process is ongoing.

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