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Covid-19ATTESTNCT05252442

Association of the Risk for Thrombotic Thrombocytopenia Syndrome and Exposure To COVID-19 Vaccines

An observational study of Covid-19, run by AstraZeneca at 1 site in United Kingdom.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Background/Rationale: A very rare syndrome of thrombosis associated with low platelets has been reported in a few cases of recent exposure to COVID-19 vaccine. This thrombotic thrombocytopenia syndrome seems to be affecting patients of all ages and both genders; at present there is no clear signal of risk factors. Read more about this study

Who is it for?
Ages 16 years and older
Conditions the study is for
Covid-19
What is being tested?
Pre-COVID-19, COVID-19 and COVID-19 vaccination roll-out
Type of treatment
Vaccines
How many people
7,641,136 participants
Where
1 siteUnited Kingdom
Study dates
1 Mar 2022to 11 Jul 2023
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 16 years and older
  • All sexes
  • No healthy volunteers
  • Child, Adult, Older adult

Study population: COVID-19 vaccinated English population with in one study historic and concurrent controls; and in the other a self-controlled case series.

Who may be able to join

  • A minimum of 12 months medical history prior to the start of the study period

Who cannot join

  • Less than 12 moths medical history prior to the start of the study period

Trial locations and contacts

1 site in 1 country.

United Kingdom1 site
  • Research site

    Oxford, OX12JD

Other trials in United Kingdom

About this study

Official title: An Assessment of a Relationship Between the Exposure to COVID-19 Vaccines and Risk of Thrombotic Thrombocytopenia Syndrome ATTEST Study (Association of the Risk for Thrombotic Thrombocytopenia Syndrome and Exposure To COVID-19 Vaccines)

Background/Rationale: A very rare syndrome of thrombosis associated with low platelets has been reported in a few cases of recent exposure to COVID-19 vaccine. This thrombotic thrombocytopenia syndrome seems to be affecting patients of all ages and both genders; at present there is no clear signal of risk factors.

Objectives: To evaluate an association between COVID-19 vaccine exposure and thromboembolic events occurring with thrombocytopenia (thrombotic thrombocytopenia syndrome; TTS).

Read more

Study design: Two primary study designs will be considered, a case control study and a self-controlled case series (SCCS). A cohort analysis will be considered, in addition or as an alternative to either of the primary study designs, pending feasibility assessment of the follow-up time.

Data Source(s): Data for the study will be accessed through the NHS Digital Trusted Research Environment (TRE), providing national data coverage. Primary care data will be linked with vaccination, hospitalization, COVID-19 test results, mortality data. Initial exploratory analyses will be conducted using the Oxford-Royal College of General Practitioners sentinel network; ORCHID network database (N>15million).

Subjects of interest are patients who have received a COVID-19 vaccine. However, investigators will require access to data from all subjects in the databases.

Statistical Analysis: The study period will start on December 02, 2020, when the COVID-19 vaccine was first approved in the UK and will end at the end of data availability.

For the case-control design, all cases of TTS will be matched with control using risk-set matching. A case or matched control will be considered exposed if a COVID-19 vaccination will be within risk interval prior to the diagnosis date of the matched case.

For the SCCS, estimates of relative incidence (RI), in all risk intervals will be reported.

For the retrospective cohort design, the incidence of TTS after receiving COVID-19 vaccine will be estimated and investigators will compare this incidence with that occurring in an unvaccinated comparator group about levels of infection across the whole population.

Variables: Demographic, socioeconomic descriptors, clinical diagnosis, vaccines, potential confounders, thrombotic phenomena, COVID-19 infection, and other characteristics as applicable.

Conditions
Covid-19
Being tested
Pre-COVID-19, COVID-19, COVID-19 vaccination roll-out
Medical subject headings
COVID-19

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Pre-COVID-19Other

    Pre-COVID-19 period

  • COVID-19Other

    COVID-19 period

  • COVID-19 vaccination roll-outOther

    COVID-19 vaccination roll-out period

Study groups in NCT05252442
Study groupRoleWhat they receive
Pre-COVID-19Not described
Receives: Other: Pre-COVID-19
COVID-19Not described
Receives: Other: COVID-19
COVID-19 vaccination roll-outNot described
Receives: Other: COVID-19 vaccination roll-out

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. thrombotic thrombocytopenia syndrome; TTS

    This is to complete studies in NHS Digital and ORCHID data

    Measured: 9 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted23 Feb 2022
  2. Study start1 Mar 2022
  3. Primary completion11 Jul 2023
  4. Study completion11 Jul 2023

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Cohort
Time perspective
Other
Enrolment
7,641,136 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05252442
Sponsor's protocol ID
D8111R00010
Acronym
ATTEST
Status last verified
May 2024
First submitted
24 Jan 2022
Last updated
30 May 2024
Results posted
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Yes: Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal. All request will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

Questions about this trial

What is this clinical trial studying?

An observational study of Covid-19, run by AstraZeneca at 1 site in United Kingdom.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 30 May 2024. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

thrombotic thrombocytopenia syndrome; TTS (time frame: 9 months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 30 May 2024.

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