Blood thinning drug to treat recovery from severe Covid is not effective

A UK-wide trial, led by Addenbrooke’s Hospital and the University of Cambridge, has found that a drug used to reduce the risk of blood clots does not help patients recovering from moderate and severe Covid – despite this approach being offered to patients.

The HEAL-COVID trial (Helping to Alleviate the Longer-term consequences of Covid-19) is funded by the NIHR and the NIHR Cambridge Biomedical Research Centre. To date, more than a thousand NHS patients hospitalised with Covid have taken part in HEAL-COVID, a platform trial that is aiming to find treatments to reduce the number who die or are readmitted following their time in hospital.

In these first results from HEAL-COVID, it’s been shown that prescribing the oral anticoagulant Apixaban does not stop Covid patients from later dying or being readmitted to hospital over the following year (Apixaban 29.1%, versus standard care 30.8%).

As well as not being beneficial, anticoagulant therapy has known serious side effects, and these were experienced by participants in the trial with a small number of the 402 participants receiving Apixaban having major bleeding that required them to discontinue the treatment.

There was also no benefit from Apixaban in terms of the number of days alive and out of hospital at day 60 after randomisation (Apixaban 59 days, versus standard care 59 days).

Following these results, the trial will continue to test another drug called Atorvastatin, a widely used lipid lowering drug (‘a statin’) that acts on other mechanisms of disease that are thought to be important in Covid.

Professor Charlotte Summers

Chief Investigator for the trial Professor Charlotte Summers, is an intensive care specialist at Addenbrooke’s Hospital and the University of Cambridge, pictured right, said: “Having survived the ordeal of being hospitalised with Covid-19, far too many patients find themselves back in hospital, often developing longer-term complications as a result of the virus. There is an urgent need for us to find treatments that prevent this significant burden of illness and improve the lives of so many still being affected by Covid.”

“These first findings from HEAL-COVID show us that a blood thinning drug, commonly thought to be a useful intervention in the post-hospital phase is actually ineffective at stopping people dying or being readmitted to hospital.  This finding is important because it will prevent unnecessary harm occurring to people for no benefit.   It also means we must continue our search for therapies that improve longer term recovery for this devastating disease.”


Dr Mark Toshner, joint Chief Investigator for HEAL-COVID, pictured left, said: “Up until now it’s been assumed that Apixaban helps patients recover after severe Covid-19 and that thinning their blood to prevent clots is beneficial.  This trial is the first robust evidence that longer anticoagulation after acute Covid-19 puts patients at risk for no clear benefit.

“Our hope is that these results will stop this drug being needlessly prescribed to patients with Covid-19 and we can change medical practise.  Finding out that a treatment doesn’t work is really important.  It’s not the solution many hoped it would be, with our results highlighting once again why testing treatments in randomised trials is important.”

“At present, the world’s research efforts have focussed on acute Covid-19. We now urgently need evidence about how to best treat patients beyond their initial infection.”

Professor Nick Lemoine, NIHR Clinical Research Network Medical Director, said: “Research into Covid-19 recovery remains vital as we move out of the pandemic. Results such as these from the HEAL-COVID study, help to strengthen our knowledge of how patients can be treated following their stay in hospital and how recovery rates can be improved upon.

“Findings from clinical trials, whether they identify new treatments or rule out methods of care, are vital and rigorous evidence when it comes to changing best medical practice.”

The trial is being led by Cambridge University Hospitals NHS Foundation Trust (CUH) and University of Cambridge, in collaboration with Liverpool Clinical Trials Centre (University of Liverpool) and Aparito Limited. 

HEAL-COVID enrols patients when they are discharged from hospital, following their first admission for Covid-19.  They are randomised to a treatment and their progress tracked.

Discover more about the NIHR Cambridge BRC

Contact us by phone, email or web for more information.

Events Calendar

Listing relevant events and training sessions for researchers and members of the public.