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Study reveals recommended anticoagulant therapy for COVID patients

Dec 13, 2022

ASCOT Media ReleaseMedia release | UNDER EMBARGO until 11 December 2022, at 03.00am (AEDT)

Study reveals recommended anticoagulant therapy for COVID patients

The AustralaSian COVID-19 Trial (ASCOT) has pinpointed the most efficient level of blood thinning treatment needed for patients hospitalised with COVID-19, in a study published in the New England Journal of Medicine Evidence and presented at the American Society for Hematology conference today.

The COVID-19 global pandemic remains a major public health challenge. ASCOT researchers aim to discover which treatments are most effective in patients hospitalised with COVID-19.

Patients in hospital with COVID-19 are at increased risk of blood clots (or thromboses), which in turn may contribute to development of organ failure. Almost all these patients will receive some degree of blood thinning medication.

In an international study, the ASCOT team conducted a randomised clinical trial to test different levels of anticoagulation (or blood thinning) in more than 1,500 patients in Australia, New Zealand, India and Nepal.

They found that an intermediate level of anticoagulation had an 86% probability of being better than low dose anticoagulation. A higher therapeutic dose did not show any benefit.

ASCOT Principal Investigator Professor Steven Tong, an infectious diseases clinician at the Royal Melbourne Hospital and co-lead of clinical research at the Doherty Institute, said that the findings will inform WHO sponsored guidelines.

“Current practice in Australia is for low dose of anticoagulation, while international guidelines recommend the high therapeutic dose of anticoagulation. Therefore, our findings provide evidence that a middle ground may be most beneficial,” Professor Tong said.

Quote attributable to Associate Professor Zoe McQuilten, Monash University Transfusion Research Unit Deputy Director and consultant haematologist with Monash University and Monash Health, Australia

“We are pleased to have our study selected for presentation at the American Society of Hematology Annual Meeting & Exposition, which is the premier haematology conference internationally."

"Importantly, we didn't find any evidence that the intermediate dose of anticoagulation resulted in increased risk of bleeding. While we didn't find evidence of benefit from the high therapeutic dose of anticoagulation, we enrolled fewer patients into that arm of the trial."


Quote attributable to Professor Bala Venkatesh, Professorial Fellow at The George Institute for Global Health, Australia

“This study highlights the importance of conducting clinical trials in different health care systems. Low- and middle-income countries (LMIC) have been under-represented in Covid-19 studies and ASCOT is one of the few studies to have a major involvement of LMIC regions. The results of the ASCOT trial are expected to have a significant influence on clinical guidelines.”


Quote attributable to Dr Susan Morpeth, Clinical Microbiologist and Infectious Diseases Physician at Middlemore Hospital, NZ

“We are pleased to be able to contribute to COVID-19 treatment trials on the ASCOT platform from Aotearoa, New Zealand. Throughout this pandemic, it has been of critical importance to accrue randomised clinical trial evidence in real time to inform clinical guidelines and patient management.”


Quote attributable to Professor Vivekanand Jha, Executive Director at The George Institute for Global Health, India

“Even as the case numbers were low in Australia and New Zealand, existing network relationships allowed us to take the trial to India and Nepal, where COVID-19 was active and successfully complete this study that asks a question of global relevance. The rapid subject recruitment during the difficult time of the delta wave is a testimony to the commitment of site investigators and study staff in these centres.”




Notes to Editors:

(1) FUNDING ASCOT is supported by the Australian Partnership for Preparedness Research on Infectious Disease Emergencies (APPRISE), The BHP Foundation, Health Research Council of New Zealand, Hospital Research Foundation, The Macquarie Group Foundation, The Minderoo Foundation, The Pratt Foundation, Royal Brisbane and Women’s Hospital Foundation, The Common Good (The Prince Charles Hospital Foundation), Wesley Medical Research, Chong Kun Dang Pharmaceutical Corporation, NSW Office for Health and Medical Research, Medical Research Future Fund (MRF2002132), and the Russell and Womersley Foundation.

(2) DOI available after embargo lifts)

About ASCOT - the AustralaSian COVID-19 Trial

ASCOT is an adaptive clinical trial that will generate clinical evidence about treatments for COVID-19 that can be applied during the pandemic to reduce mortality or the need for mechanical ventilation in hospitalised but not yet critically ill patients with COVID-19. The trial aims to generate results quickly from sites in Australia, New Zealand, India and Nepal. Over 1,500 patients have been treated already. Results will be continually analysed, so that ineffective therapies can be stopped, and new therapies can be evaluated as part of the trial.

The trial investigates different types of treatments:

  • Antiviral and antibody therapies – which aim to limit the virus replicating
  • Anticoagulation therapies – which aim to reduce the risk of blood clots associated with COVID-19 infection
  • Others such as immunomodulators.  @ascot_trial

About the Peter Doherty Institute for Infection and Immunity

Finding solutions to prevent, treat and cure infectious diseases and understanding the complexities of the immune system requires innovative approaches and concentrated effort. This is why The University of Melbourne – a world leader in education, teaching and research excellence – and The Royal Melbourne Hospital – an internationally renowned institution providing outstanding care, treatment and medical research – have partnered to create the Peter Doherty Institute for Infection and Immunity (Doherty Institute); a centre of excellence where leading scientists and clinicians collaborate to improve human health globally.   /DohertyInstitute   @TheDohertyInst #DohertyInstitute

The George Institute for Global Health

The George Institute for Global Health is an independent medical research institute aiming to improve the health of millions of people worldwide by generating effective, evidence-based and affordable solutions to the world’s biggest health challenges. Established in Sydney, with major centres in China, India and the UK, it has projects in more than 45 countries and affiliations with world-class universities. In 2018, The George Institute was ranked the number-one independent research institute in Australia by Times Higher Education.  /thegeorgeinstitute   @georgeinstitute

Te Kohinga Ora | Middlemore Clinical Trials

Middlemore Clinical Trials (MMCT), is a fully integrated specialist clinical trial unit based within one of New Zealand’s largest hospitals, Middlemore Hospital in South Auckland. Established in 2001, MMCT is an independent charitable trust that administers both commercial and grant funded research on behalf of Middlemore Hospital Te Whatu Ora Counties Manukau. MMCT has established a strong track record of success in Phase I-III trials and the management of grant funded trials. We are passionate about bringing health research to New Zealand so that our community can benefit from the opportunity to be part of leading-edge science and novel therapies from around the world.  /MMClinTrials    @MMClinTrials #MMCT


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