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

NCT05252442 | Completed

• 1 other identifier: D8111R00010
• Study Type: observational
• Target: 7,641,136
• Locations: 1 country
• Sites: 1

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

Outcome Measures

Primary Outcomes (1)

• thrombotic thrombocytopenia syndrome; TTS

  This is to complete studies in NHS Digital and ORCHID data

  9 months

Study Arms (3)

Pre-COVID-19

Other: Pre-COVID-19

COVID-19

Other: COVID-19

COVID-19 vaccination roll-out

Other: COVID-19 vaccination roll-out

Interventions

Pre-COVID-19 OTHER

Pre-COVID-19 period

Pre-COVID-19

COVID-19 OTHER

COVID-19 period

COVID-19

COVID-19 vaccination roll-out OTHER

COVID-19 vaccination roll-out period

COVID-19 vaccination roll-out

Eligibility Criteria

• Age: 16 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

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

You may qualify if:

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

You may not qualify if:

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

Sponsors & Collaborators

• AstraZeneca: lead

Study Sites (1)

Research site

Oxford, OX12JD, United Kingdom

Location

Related Links

• D8111R00010\_Redacted CSR Synopsis

MeSH Terms

Conditions

COVID-19

Condition Hierarchy (Ancestors)

Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: OTHER
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 24, 2022
• First Posted: February 23, 2022
• Study Start: March 1, 2022
• Primary Completion: July 11, 2023
• Study Completion: July 11, 2023
• Last Updated: May 30, 2024

Record last verified: 2024-05

Data Sharing

• IPD Sharing: Will share
• Time Frame: AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA Pharma Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.
• Access Criteria: When a request has been approved AstraZeneca will provide access to the deidentified individual patient-level data in an approved sponsored tool . Signed Data Sharing Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information. Additionally, all users will need to accept the terms and conditions of the SAS MSE to gain access. For additional details, please review the Disclosure Statements at: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Locations

GB (1)