Favipiravir +/- Nitazoxanide: Early Antivirals Combination Therapy in COVID-19

FANTAZE is a Phase IIA randomised, double-blind, placebo-controlled, interventional trial.Participants will be adults who have developed the early symptoms of COVID-19 within the first 5 days, or tested positive for SARS-CoV-2 within the first 7 days of symptom onset, or not presenting symptoms but tested positive within the last 48 hours (date/time of test must be within 48 hours of enrolment). Eligible participants will be randomised 1:1 to receive one of the following combinations: Favipiravir + Nitazoxanide (both active); Favipiravir active + Nitazoxanide placebo; All participants will be enrolled and followed up for 28 days. A saliva sample for virological analysis and safety blood samples will be collected at baseline, as well as a diagnostic nose and throat swab, if the participant hasn't been tested for COVID-19 yet. Following randomisation, participants will take trial medication for 7 days and during this period will take a daily saliva sample and complete a symptoms diary including four daily temperature measurements. Participants will have two follow-up visits at Day 7 and Day 14 where they will be assessed and undergo blood tests for toxicity and pharmacokinetic assessment (on Day 7 only) and provide stool samples. Participants will have a telephone follow up three (3) weeks after their last day of treatment (Day 7) and further information will be collected through a questionnaire.