Philippine Trial to Determine Efficacy and Safety of Favipiravir for COVID-19

Inclusion Criteria: * Age: 18 to 74 years (at the time of informed consent) * Gender: Male or female * Patients with SARS-CoV-2-positive nasopharyngeal swab by RT-PCR test with non-severe presentation upon admission to clinical trial site hospitals or trial-supervised quarantine facilities or under trial -supervised home isolation; * For premenopausal female patients, patients who have been confirmed to be negative on a pregnancy test before administration of the study drug; * Patients who understand the contents of this study and can provide written consent by themselves without assistance, or as appropriate with their assent and consent of their parents Exclusion Criteria: * Patient has manifestation that meets case definition of Severe COVID-19: Adult with clinical signs of pneumonia (fever, cough, dyspnea, fast breathing) plus one of the following: respiratory rate \> 30 breaths/min; severe respiratory distress; or SpO2 \< 90% on room air. * Fever (37.5°C) more than 7 days after the onset of fever * Patients with suspected concomitant bacterial infections (e.g. 1 ng/ml or higher procalcitonin, etc.) prior to initiation of study drug * Patients with suspected concomitant fungal infections (e.g. 30 pg/ml or higher (1-3)-β-d-glucan, etc.) prior to initiation of study drug * Patients with suspected concurrent congestive heart failure (e.g. 100 pg/mL or higher NT-pro BNP levels, etc.) prior to initiation of study drug * Patients with severe hepatic impairment (\>Grade 3: ALT \>10 times of upper normal limit) * Patients with renal impairment requiring dialysis * Patients with disturbed consciousness such as disturbed orientation * Pregnant or possibly pregnant patients * Female patients who are unable to consent to contraceptive use of oral contraceptives, mechanical contraceptives such as intrauterine devices or barrier devices (pessaries, condoms), or a combination of these devices during the 7 days after the start of favipiravir administration. * Male patients whose partner cannot agree to use the contraception method described in (10) above * Patients who cannot consent to the use of condoms from the start of favipiravir administration to 7 days after the end of favipiravir administration * Patients with hereditary xanthinuria * Patients who have previously ever been diagnosed with hypouricemia (\< 1 mg/dL) or xanthine urinary calculi * Patients with a history of gout or on treatment for gout or hyperuricemia * Patients receiving immunosuppressants * Patients who received interferon-alpha or drugs with reported antiviral activity against SARS-CoV-2 (hydroxychloroquine sulfate, chloroquine phosphate, lopinavir-ritonavir combination, ciclesonide, nafamostat mesylate, camostat mesylate) within 9 days after fever (37.5°C or more). * Patients in whom this episode of infection is a recurrence or reinfection of SARS-CoV-2 infection * Patients who have previously received favipiravir (T-705a) * Other patients judged ineligible by the principal investigator or sub-investigator