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Covid-19 Primary Care Resources


PRINCIPLE Trial


Oxford vaccine


One of the largest Covid studies relevant to general practice in the UK

This information is sourced from the Primary Care Clinical Trials Unit, University of Oxford and correspondence with the trial organisers. Updated, 7 May 2021.

Brief outline;

Led by the Primary Care Clinical Trials Unit at Oxford University. The Platform Randomised trial of Interventions against COVID-19 in older people (PRINCIPLE) trial involves over 1,000 GP practices.  It is testing which pharmacological treatments are more effective at reducing morbidity in high risk patients with COVID-19.

Signing up

As of 7 May 2021, the trial is no longer opening new GP practices to participate in the trial in the traditional sense: ie, they do not require a formal site agreement, RCGP and ImmForm registered, GCP trained staff etc. in order to take part.

Instead, GPs are asked to regularly screen their positive test patient lists and signpost/refer any potentially eligible patients to its trial website: https://www.principletrial.org/ or freephone number 0800 138 0880 where patients can register and consent to the trial remotely.

Furthermore, all trial activity is managed by the central trial team so sites do not need to send out swab test kits or medication to participants. They only ask that sites to complete a short notes review of the 28 day period that participants take part in the trial, and they reimburse at £50 per participant for their time.

Treatments being trialled

Favipiravir, an antiviral drug used to treat flu was added to the PRINCIPLE trial in April 2021. 

In March, it launched its investigation of the gout drug colchicine, which expanded for the first time to include adults of any age. Previously, only those with Covid-19 aged 50 or over and at most risk of complications from the illness were eligible to join the PRINCIPLE trial. For the colchicine arm, the trial now includes participants either aged 18-64 with shortness of breath from the illness or certain underlying health conditions that put them at risk of severe illness, or those aged over 65. Participants are only eligible to join the trial during the first 14 days of Covid-19 illness.