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Antiviral added to COVID-19 PRINCIPLE trial

Favipiravir PRINCIPLE   1200 x 375

A trial into supporting people with suspected COVID-19 to stay out of hospital has added its first antiviral drug.

Favipiravir is the sixth medication to be entered into PRINCIPLE and is currently licensed in Japan to treat influenza.

The University of Oxford study is the world’s largest clinical trial of possible COVID-19 treatments for recovery at home and in other non-hospital settings.

Favipiravir works by inhibiting a viral enzyme called RNA polymerase, preventing viral replication within human cells. This viral enzyme is common to several viruses, including SARS-CoV-2, which causes COVID-19.

The drug has shown positive results against SARS-CoV-2 in laboratory and animal studies, with small pilot studies in humans demonstrating some benefit in reducing symptoms and the duration of illness.

Launched in March 2020, PRINCIPLE has so far recruited more than 4,700 volunteers from across the UK, including 275 in Berkshire, Buckinghamshire, Milton Keynes and Oxfordshire.

It is recruiting participants who are most at risk of serious COVID-19 illness, either due to their age, symptoms, or an underlying health condition.

Participants can join from anywhere in the UK, either online, over the phone or via a healthcare professional, and without needing face-to-face visits with the trial team in Oxford.

PRINCIPLE trial Co-Investigator, Gail Hayward, an Oxfordshire GP and Associate Professor in the University of Oxford’s Nuffield Department of Primary Care Health Sciences, said: “Even with the successful vaccine rollout, it’s the combination of vaccines, testing and treatments that will bring an end to this pandemic.

“There still isn’t a safe and effective therapeutic for COVID-19 that we know for sure will prevent people needing to go into hospital for treatment. By joining the PRINCIPLE trial, people with coronavirus symptoms could play a vital role in helping to transform COVID-19 into an illness that can potentially be treated by your regular general practitioner.”

Other treatments under investigation include budesonide, an inhaled steroid typically used for treating lung inflammation, and colchicine, an anti-inflammatory drug traditionally used for treating gout, which is being evaluated in adults aged over 18.

The trial has so far found that the antibiotics azithromycin and doxycycline are not generally effective as treatments during the early stages of COVID-19, with implications for how COVID-19 illness is treated both in the UK and internationally.

To find out more about how to join the study, visit

Read more on the University of Oxford website.