Phase IIa Randomized Placebo Controlled Clinical Study of Codivir in Hospitalized Patients with Moderate COVID-19

Inclusion Criteria: * Age between 18 and 75 years * Male or female * SARS-CoV-2 infection indicated by confirmed RT-PCR test * Moderate hospitalized COVID-19 (at least two out of three criterias below): * Evidence of lower respiratory disease during clinical assessment (cough, fever, difficulty breathing) or imaging (X-rays) * Oxygen saturation (SpO2) in room air \< 93% * \<30 breaths per minute * No signs of hemodynamic decompensation * Absence of pregnancy in women of childbearing age * Ability to understand and comply with the requirements of the protocol * Consent to participate * Consent to use at least one highly effective contraception methods (condoms, IUD, oral contraceptives) since the ICF signature and at least 30 days after the study. Exclusion Criteria: * Patients receiving oxygen supplementation except of nasal prongs, nasal intermittent positive pressure ventilation (NIPPV) or high flow nasal cannula (HFNC) that are allowed to be enrolled to the study). * Positive RT-PCR test more than 72 hours prior to enrolment. * Onset of symptoms more than 7 days prior to enrolment. * Participant using drugs that are under clinical investigation in last 30 days. * Body mass index less than 19.9 or greater than 35. * Comorbidities such as: other serious infections, active malignancies, autoimmune diseases, liver, kidney or heart failure; another systemic disease and / or laboratory abnormality, which, in the investigator's opinion, prevent the patient from participating in the study. * Concomitant HIV, HBV or HCV infection. * Pregnancy or lactation. * Vaccination for any other infection in the 4 weeks prior to enrolment. * Any condition that increases the risk of participating in the study, in the opinion of the investigator.