AstraZeneca COVID-19 vaccine: review of very rare cases of unusual blood clots continues

European Medicines Agency - 4/7/2021 11:20:00 AM

European Medicines Agency

EMA's safety committee (PRAC) is meeting today, Wednesday 31 March, in the context of its ongoing review of very rare cases of unusual blood clots associated with low numbers of platelets, in people vaccinated with AstraZeneca's COVID-19 vaccine (now called Vaxzevria).

EMA convened an ad hoc expert group meeting on Monday 29 March to provide further input into the ongoing assessment. Independent external experts with a range of medical specialities, including haematologists, neurologists and epidemiologists, discussed specific aspects such as possible mechanisms, whether underlying risk factors could be identified and what additional data are needed to further characterise the observed events and the potential risk. The outcome of this meeting will be discussed by the PRAC and feed into its ongoing evaluation.

At present the review has not identified any specific risk factors, such as age, gender or a previous medical history of clotting disorders, for these very rare events. A causal link with the vaccine is not proven, but is possible and further analysis is continuing.

As communicated on 18 March, EMA is of the view that the benefits of the AstraZeneca vaccine in preventing COVID-19, with its associated risk of hospitalisation and death, outweigh the risks of side effects.

More information and advice for healthcare professionals and the public is available in the vaccine's product information and the associated direct healthcare professional communication. Vaccinated people should be aware of the remote possibility of these very rare types of blood clots occurring. If they have symptoms suggestive of clotting problems as described in the product information, they should seek immediate medical attention and inform healthcare professionals of their recent vaccination.

EMA continues to work with the national authorities in the EU Member States to ensure that suspected cases of unusual blood clots are reported; these cases are being analysed in PRAC's ongoing assessment.

Based on all the currently available data, PRAC is expected to issue an updated recommendation during its April plenary meeting (6-9 April).

The report describing the PRAC's preliminary assessment of the reported cases of blood clots and conclusions is available.
More about the procedure

The review of cases of very rare cases of unusual blood clots associated with low blood platelets (thrombocytopenia) is being carried out in the context of a safety signal, under an accelerated timetable. A safety signal is information on a new or incompletely documented adverse event that is potentially caused by a medicine such as a vaccine and that warrants further investigation.

The review is being carried out by EMA's Pharmacovigilance Risk Assessment Committee (PRAC), the Committee responsible for the evaluation of safety issues for human medicines. Once the review is completed, PRAC will make any recommendations necessary to minimise risks and protect patients' health. The PRAC recommendations will then be sent to the Committee for Medicinal Products for Human Use (CHMP), responsible for questions concerning medicines for human use, which will rapidly adopt the Agency's opinion.

EMA provides scientific recommendations underpinning the safe and effective use of COVID-19 vaccines.

EMA's recommendations are the foundation upon which individual EU Member States will design and implement their own national vaccination campaigns. These may differ from country to country depending on their national needs and circumstances, such as infection rates, priority populations, vaccine availability and hospitalisation rates

The European Medicines Agency (EMA) is a decentralised agency of the European Union (EU) responsible for the scientific evaluation, supervision and safety monitoring of medicines in the EU.

EMA is governed by an independent Management Board. Its day-to-day operations are carried out by the EMA staff, overseen by EMA's Executive Director.

EMA is a networking organisation whose activities involve thousands of experts from across Europe. These experts carry out the work of EMA's scientific committees.

On 2 March 2020, EMA implemented changes to its organisational structure to ensure that it operates as efficiently as possible to deliver high quality outputs for public and animal health.

The main changes comprise:

integrating operations in the area of human medicines into one human medicines division;
establishing four mission-critical task forces to support the human and veterinary medicines divisions, bringing together expertise to drive transformational change in high-priority areas.

The re-organisation exercise takes into account the rapidly evolving landscape for pharmaceutical research and development that requires regulators to keep up with advances in science and technology and prepare for future challenges at an ever-accelerating pace.

The change is also driven by the need to recalibrate to a lower head count following the EMA's relocation to Amsterdam in 2019 whilst dealing with an increased workload due the implementation of various new legislation relating to clinical trials, veterinary medicines, medical devices and data protection.
Management Board

The Management Board consists of 36 members, appointed to act in the public interest, who do not represent any government, organisation or sector.

The Board sets the Agency's budget, approves the annual work programme and is responsible for ensuring that the Agency works effectively and co-operates successfully with partner organisations across the EU and beyond.
Executive Director

The Agency's Executive Director is the legal representative of the Agency. She is responsible for all operational matters, staffing issues and drawing up the annual work programme.
Agency staff

The Agency's staff support the Executive Director in carrying out his responsibilities, including administrative and procedural aspects of EU law related to the evaluation and safety-monitoring of medicines inthe EU.

Scientific Committees

EMA has seven scientific committees that evaluate medicines along their lifecycle from early stages of development, through marketing authorisation to safety monitoring once they are on the market.

In addition, the Agency has a number of working parties and related groups, which the committees can consult on scientific issues relating to their particular field of expertise.

These bodies are composed of European experts made available by national competent authorities of the EU Member States, which work closely with EMA in the European medicines regulatory network.
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