This is open-labe randomized multicenter comparative Phase III study conducted in 8 medical facilities. The objective of the study is to assess the efficacy, safety and tolerability of Ambervin for intramuscular and inhaled administration in complex therapy COVID-19 compared with the Standard of care (SOC) in hospitalized patients with moderate COVID-19.

Upon signing the informed consent form and screening, 313 eligible patients hospitalized with COVID-19 were randomized at a 1:1:1 ratio to receive either Ambervin intramuscular 1mg 1 times a day for 10 days or Ambervin inhaled 10mg 1 times a day for 10 days or SOC.

Inclusion Criteria:

1. Availability of the Informed Consent Form of thePatient Information Leaflet (PIL) signed and dated bypatient.

2. Men and women aged 18 to 80 years inclusive at thetime of signing the Informed Consent Form in PIL.

3. Confirmed case of COVID-19 at the time ofscreening based on SARS-CoV-2 RNA test usingnucleic acid amplification (NAA) method. It isacceptable to include a patient with a presumptiveCOVID-19 diagnosis prior to receiving the results ofSARS-CoV-2 RNA test made at the screening stage.

4. Hospital admission due to COVID-19.

5. Moderate severity infection with SARS-CoV-2: Clinical signs (the presence of at least 2 of the following criteria):

   • body temperature > 38 °C;
   • RR > 22/min;
   • CT pattern typical of a viral lesion
   • shortness of breath on exertion;
   • SpO2 < 95%;
   • Serum CRP > 10 mg/L.

6. Lesion volume is minimal or moderate; CT 1-2.

7. Patient's consent to use reliable contraceptive methods through out the study and within 1 month for women and 3 months for men after its completion. Reliable means of contraception are: sexualabstinence, use of condom in combination withspermicide.

Women incapable of childbearing may also participate inthe study (with past history of: hysterectomy, tubal ligation,infertility, menopause for more than 2 years), as well asmen with infertility or a history of vasectomy

Exclusion Criteria:

1. Hypersensitivity to components of the study drug.
2. Impossibility of CT procedure (for example, gypsumdressing or metal structures in the field of imaging).
3. Obstacles or inability to perform intramuscular injections and / or inhalations
4. Arterial hypotension (a decrease in blood pressure (BP) below 100/60 mm Hg) at the time of screening and / or a history of hypotensive crises.
5. The need for the use of drugs from the list of prohibited therapies.
6. Availability of criteria for severe and extremely severe disease at the time of screening
7. Presence within 6 months prior to screening of a probable or confirmed case of moderate COVID-19
8. History of presumptive or confirmed COVID-19 caseof moderate, severe and extremely severe course ofthe disease.
9. Vaccination less than 4 weeks prior to screening.
10. The need for treatment in the intensive care unit at the time of screening.
11. Impaired liver function (AST and/or ALT ≥ 2 UNLand/or total bilirubin ≥ 1.5 UNL) at the time ofscreening.
12. Renal impairment (GFR < 60 ml/min) at the time of screening.
13. Positive testing for HIV, syphilis, hepatitis B and/or C.
14. Chronic heart failure FC III-IV according to New York Heart Association (NYHA) functional classification.
15. Malignancies in the past medical history.
16. Alcohol, pharmacological and/or drug addiction in the past medical history and/or at the time of screening.
17. Epilepsy in history.
18. Schizophrenia, schizoaffective disorder, bipolardisorder, or other history of mental pathology orsuspicion of their presence at the time of screening.
19. Severe, decompensated or unstable somatic diseases (any disease or condition that threaten thepatient's life or impair the patient's prognosis, and also make it impossible for him/her to participate in the clinical study).
20. Any history data that the investigating physician believes could lead to complication in the interpretation of the study results or create an additional risk to the patient as a result of his/her participation in the study.
21. Patient's unwillingness or inability to comply with procedures of the Study Protocol (in the opinion of physician investigator).
22. Pregnant or nursing women or women planning pregnancy.
23. Participation in another clinical study for 3 monthsprior to inclusion in the study.
24. Other conditions that, according to the physicianinvestigator, prevent the patient from being includedin the study.