Patient case (clinical description): The patient is a 38-year-old man with cough and body ache that started 3 days ago.  He had fever and chills at the beginning and has low grade fever at the time of visit. He feels tired and sleepy. His body ache and myalgia get better after using Tylenol. The PCR test for Covid is positive. His vital signs are within normal limits with a body temperature of 37.9 C. There is no lymphadenopathy or white exudates in the pharynx.

Patient's own account: I was feeling really sick the other day, to the point that I showed up at the doctor's office. I was coughing, and my body was hurting for 3 days. I had a fever and chills and felt tired and sleepy. I got better after using Tylenol. They did a PCR Covid test on me, and it was positive! My vitals were normal, and my temperature was 37.9 C. I had no swelling around my neck or white spots on the back of my throat.

Clinical trial: Recombinant Human Angiotensin-converting Enzyme 2 (rhACE2) as a Treatment for Patients With COVID-19

Eligibility criteria:
Inclusion Criteria:

          1. Laboratory diagnosis:

               -  Respiratory specimen is positive for SARS-CoV-2 nucleic acid by RT-PCR; OR,

               -  The viral gene sequencing of the respiratory specimen is highly homologous to
                  known novel coronavirus.

          2. Fever:

             Axillary temperature >37.3℃

          3. Respiratory variables (meets one of the following criteria):

               -  Respiratory rate: RR ≥25 breaths/min

               -  Oxygen saturation ≤93% at rest on room air

               -  PaO2/FiO2 ≤300 mmHg（1 mmHg=0.133 KPa）

               -  Pulmonary imaging showed that the lesions progressed more than 50% within 24-48
                  hours, and the patients were managed as severe

          4. HBsAg negative, or HBV DNA ≤10^4 copy/ml if HBsAg positive; anti-HCV negative; HIV
             negative two weeks prior to signed Informed Consent Form (ICF)

          5. Appropriate ethics approval and

          6. ICF

        Exclusion Criteria:

          -  Age <18 years; Age >80 years

          -  Pregnant or breast feeding woman or with positive pregnancy test result

          -  P/F <100 mmHg

          -  Moribund condition (death likely in days) or not expected to survive for >7 days

          -  Refusal by attending MD

          -  Not hemodynamically stable in the preceding 4 hours (MAP ≤65 mmHg, or SAP <90 mmHg,
             DAP <60 mmHg, vasoactive agents are required)

          -  Patient on invasive mechanical ventilation or ECMO

          -  Patient in other therapeutic clinical trial within 30 days before ICF

          -  Receive any other ACE inhibitors (ACEI), angiotensin-receptor blockers (ARB) treatment
             within 7 days before ICF

          -  Chronic immunosuppression: current autoimmune diseases or patients who received
             immunotherapy within 30 days before ICF

          -  Hematologic malignancy (lymphoma, leukemia, multiple myeloma)

          -  Other patient characteristics (not thought to be related to underlying COVID-19) that
             portend a very poor prognosis (e.g, severe liver failure, and ect)

          -  Known allergy to study drug or its ingredients related to renin-angiotensin system
             (RAS), or frequent and/or severe allergic reactions with multiple medications

          -  Other uncontrolled diseases, as judged by investigators

          -  Body weight ≥85 kg
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.
Subject must be at most 80 Years

Eligibility (NLI label): Contradiction