The COVID Symptom Study app and Oxford University partner on COVID-19 treatment trials

August 5, 2020

This article has not been updated recently

Oxford University and the COVID Symptom Study app are joining forces to widen access to two clinical trials of potential treatments for COVID-19. 

The COVID Symptom Study App was developed and is managed by health technology company ZOE, with the research using data from the app being undertaken by academics at King's College London. The app has now been downloaded by over 3.5 million people in the UK and has recruited over 800,000 citizen scientists to its Vaccine and Trial Registry.

The registry was launched on 9 July and aims to raise awareness and rapidly recruit members of the public to the growing number of national and community-based clinical trials for COVID-19 in the UK.

Those users who have already signed up to the COVID Symptom Study Vaccine and Trial registry and test positive for COVID-19, or show signs of symptomatic COVID in the app, will be contacted and given the opportunity to join Oxford University’s PRINCIPLE and STOIC trials.


The PRINCIPLE Trial is evaluating whether treatment early on in the community can help people aged over 50 recover quickly from COVID-19 illness, without the need for hospital admission.

The trial, which is open across the UK to people aged over 50 with an underlying health condition or anyone aged over 65, can be easily joined online from home without face-to-face visits, or via GP practices across the country. It is one of the UK Government’s four national priority platform trials on COVID-19 treatments.

PRINCIPLE is currently evaluating azithromycin and doxycycline, which are two commonly prescribed antibiotics. These drugs are thought to have anti-viral and anti-inflammatory properties against coronavirus, and also treat bacterial infections like pneumonia, which is a common reason for deterioration in people with COVID-19. 

665 people have already signed-up to take part, but many more are needed to determine whether either of the treatments can help treat the disease. The collaboration with the COVID Symptom Study app will help to link eligible individuals with the PRINCIPLE trial. 

The STOIC study

The STOIC (STerOids In COVID) study is investigating the early use of a steroid inhaler, in people with symptoms suggestive of COVID-19, as a treatment to reduce the chance of needing to go to hospital. Inhaled steroids are a type of medicine which reduces inflammation, so their use early in the disease course of COVID-19 could reduce the inflammation caused by the virus and help prevent severe disease. 

The STOIC study is open to anyone over the age of 18 with new symptoms suggestive of COVID-19 within the last seven days. To get the study treatment (a Budesonide steroid inhaler) as early as possible, a positive test result is not necessary to join the study. Volunteers can participate from home, with the trial’s research nurses dropping off all the study equipment and medications on participants’ doorsteps. All volunteers in the STOIC study will be provided with an oxygen monitor and a thermometer to detect any signs of worsening symptoms, and everyone will be monitored via daily phone calls with the study’s clinical team. The study is now looking for volunteers in the Thames Valley and will expand to other areas in the next few weeks.

Tim Spector, Professor of Genetic Epidemiology at King's College London, and lead scientist at the COVID Symptom Study app comments: 

“We are really excited to be partnered with Oxford University. This is exactly why we set up the Vaccine and Trial Registry. We have millions of engaged loyal users, who all want to help play a role in the fight against COVID and this collaboration will help us link those individuals up with trials. Both the PRINCIPLE and the STOIC trials are conducting essential research, especially whilst we have no effective vaccine yet. This work will save lives and as always, we want to thank all our amazing users as they continue to allow us to make a real impact on COVID-19.” 

Professor Chris Butler, a GP and Co-Lead of the PRINCIPLE Trial at the University of Oxford’s Nuffield Department of Primary Care Health Sciences, said: 

"Until an effective vaccine is developed and made widely available, treating people at home who show symptoms of COVID-19 is the only way to help most people who get this awful illness to recover more quickly, and prevent those who are at most risk of serious illness from having to go to hospital."
"PRINCIPLE will answer a pressing question - which of the treatments showing promise against COVID-19 are effective in people at higher risk of complications early on in the illness? With the prospect of a second wave later this year, we urgently need many more people to join the trial to determine which, if any, of these drugs can be introduced into usual care. Our partnership with the COVID Symptom Study is an important step in facilitating access to this trial for those users who test positive for the disease."

Professor Mona Bafadhel, the STOIC study Chief Investigator, Associate Professor of Respiratory Medicine in the Nuffield Dept of Medicine at the University of Oxford and a Consultant Respiratory Physician at the Oxford University Hospitals NHS Foundation Trust,  said 

“We know that steroid tablets or injections given in severe disease can help prevent death in COVID-19. We want to test if steroids in an inhaler form, like those given to patients with asthma and COPD, can stop people getting worse from COVID-19 when given early. Inhaled steroids are cheap medicines that are widely available throughout the world.  The STOIC study has been designed to answer this question and we are excited to work with the investigators at Kings College London and the ZOE team."

PRINCIPLE is funded by UK Research and Innovation and the Department of Health and Social Care through the National Institute for Health Research (NIHR), STOIC is funded by the NIHR Oxford Biomedical Research Centre.

Additional information:

Download the COVID Symptom Study app here:

Find out more about how to join the PRINCIPLE Trial here:  

Find out more and join the STOIC trial at: 

About ZOE

ZOE is a health science company using data-driven research to tackle the world’s health issues. By using artificial intelligence combined with digital technologies like mobile phones, ZOE enables large-scale scientific studies to tackle issues like COVID-19, inflammation and the impact of nutrition on health. 

Located in London and Boston, ZOE was founded by machine learning leader Jonathan Wolf and entrepreneur George Hadjigeorgiou. ZOE along with Professor Tim Spector of King’s College London. ZOE has carried out the largest nutritional studies of their kind in the world, runs the COVID Symptom Study app with 4 million users around the world, and was named one of the Deloitte Fast 50 Rising Stars in 2019 for the company’s contribution to science enabled by technology and machine learning. 

For more information on ZOE’s mission and science visit

About the PRINCIPLE Trial

The UK-wide PRINCIPLE trial platform is led from the Primary Care Clinical Trials Unit at the University of Oxford’s Nuffield Department of Primary Care Health Sciences. The trial is integrated with the Oxford RCGP Research and Surveillance Centre and works closely with the NIHR Clinical Research Network across England and similar networks in the devolved nations. The trial is funded from as part of the UK Government’s rapid research response fund. Within the University of Oxford, the Nuffield Department of Primary Care Health Sciences is the largest, top-ranked centre for academic primary care in the UK, bringing together academics from many different backgrounds to work together to produce benefits for the NHS, for populations and for patients.

About the STOIC trial

The Nuffield Department of Medicine University of Oxford led STOIC study is recruiting volunteers with symptoms of COVID-19 to trial inhaled steroids. The study hopes to show that early use of inhaled steroids will reduce the risk of emergency department visit and hospitalisation due to COVID-19. The study also proposes a home based, clinician led monitoring program to detect early deterioration of COVID-19.

The study is supported by the NIHR Oxford Biomedical Research Centre and AstraZeneca. The study is now recruiting in the Thames Valley and is opening in other areas in the UK in the next few weeks. Visit for more information. 

About the National Institute for Health Research:

The National Institute for Health Research (NIHR) is the nation's largest funder of health and care research. The NIHR:

  • Funds, supports and delivers high quality research that benefits the NHS, public health and social care
  • Engages and involves patients, carers and the public in order to improve the reach, quality and impact of research
  • Attracts, trains and supports the best researchers to tackle the complex health and care challenges of the future
  • Invests in world-class infrastructure and a skilled delivery workforce to translate discoveries into improved treatments and services
  • Partners with other public funders, charities and industry to maximise the value of research to patients and the economy

The NIHR was established in 2006 to improve the health and wealth of the nation through research, and is funded by the Department of Health and Social Care. In addition to its national role, the NIHR supports applied health research for the direct and primary benefit of people in low- and middle-income countries, using UK aid from the UK government.

This work uses data provided by patients and collected by the NHS as part of their care and support and would not have been possible without access to this data. The NIHR recognises and values the role of patient data, securely accessed and stored, both in underpinning and leading to improvements in research and care. 

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