1. History of hypersensitivity to interferon or JH509 or any excipients of interferon or JH509.2. Have received antiviral treatments and drugs expected to have antiviral effects (favipiravir, remdesivir, interferon, nafamostat mesilate, and casirivimab/imdevimab, including drugs that are being newly developed and that have been approved) in the past or having had it considered necessary to receive these treatments during the study period.3. Having had it considered necessary to receive treatments, such as drugs containing corticosteroids (excluding topical drugs), antimicrobial agents, and inhalants other than the investigational drug during the study period.4. Taking Shosaikoto, an herbal medicine.5. Neuropsychiatric disorder and autoimmune disorder.6. CTCAE Grade 3 or higher liver dysfunction (ALT/AST > 5ULN) or renal dysfunction (eGFR < 30 mL/min/1.73 m2).7. Active infections or other medical conditions that contraindicate inhalation therapy.8. Having the complication of malignant tumor or a history of malignant tumor within 1 year before consent acquisition.9. Inappropriate for inclusion in the clinical trial as determined by investigators or subinvestigators.

1. History of hypersensitivity to interferon or JH509 or any excipients of interferon or JH509.2. Have received antiviral treatments and drugs expected to have antiviral effects (favipiravir, remdesivir, interferon, nafamostat mesilate, and casirivimab/imdevimab, including drugs that are being newly developed and that have been approved) in the past or having had it considered necessary to receive these treatments during the study period.3. Having had it considered necessary to receive treatments, such as drugs containing corticosteroids (excluding topical drugs), antimicrobial agents, and inhalants other than the investigational drug during the study period.4. Taking Shosaikoto, an herbal medicine.5. Neuropsychiatric disorder and autoimmune disorder.6. CTCAE Grade 3 or higher liver dysfunction (ALT/AST > 5ULN) or renal dysfunction (eGFR < 30 mL/min/1.73 m2).7. Active infections or other medical conditions that contraindicate inhalation therapy.8. Having the complication of malignant tumor or a history of malignant tumor within 1 year before consent acquisition.9. Inappropriate for inclusion in the clinical trial as determined by investigators or subinvestigators.