Study to Evaluate the Efficacy, Safety, and Tolerability of the Ingavirin Forte Capsules (Valenta Pharm JSC) at Different Doses in Subjects With Influenza and Other Acute Respiratory Viral Infections.

Exclusion Criteria36

• Clinically significant allergic history;
• Hypersensitivity to active substances of medical produtcs Ingavirin and Ingavirin forte, and/or to any excipient contaned in the investigational medicinal product or comparator;
• Intolerance to active substances of medical produtcs Ingavirin and Ingavirin forte, and/or to any excipient contaned in the investigational medicinal product or comparator;
• Known galactose intolerance, lactase deficiency, or glucose-galactose malabsorption;
• Clinical suspicion of pneumonia of any etiology, or other bacterial infection (e.g. sinusitis, otitis media, urinary tract infection, meningitis, sepsis) requiring initiation for antibacterial therapy;
• Nasal obstruction due to structural pathology, such as sequelae of nasal trauma, nasal polyps, septal deviation, or other organic causes;
• History of vasomotor rhinitis;
• Administration of antibiotics, antiviral (including Ingavirin), or immunomodulatory agents within 48 hours prior to study, and/or anticipated need for any of these agents during the study;
• Vaccination within 90 days prior to study enrollment;
• Uncontrolled diabetes mellitus;
• Obesity, class II or III (body mass index ≥35 kg/m²);
• Pregnancy or lactation;
• Positive test for SARS-CoV-2 at screening;
• History of autoimmune diseases;
• Current or past HIV, syphilis, hepatitis B and/or C, or tuberculosis;
• Known or suspected history of alcohol, psychotropic drug, or substance abuse or dependence;
• History of chronic respiratory disease, including but not limited to: chronic obstructive pulmonary disease (COPD), asthma, chronic bronchitis, diffuse panbronchiolitis, pulmonary emphysema, or pulmonary fibrosis;
• Chronic heart failure, New York Heart Association (NYHA) functional class III or IV;
• Current or past psychiatric disoder;
• Any clinically significant cardiovascular, renal, hepatic, gastrointestinal , endocrine, or neurological disoder, including severe uncompensated chronic conditions (e.g., chronic kidney disease, chronic liver disease) or acute illness, or any other medical or psychiatric condition that, in investigator's opinion, could pose a safety risk to the subject if they participate in the study;
• Subject's refusal to use an adequate method of contraception or to practice continuous sexual abstinence throughout the study and for 30 days after study completion;
• Participation in another clinical trial within 3 months prior to screening;
• Other conditions which, in the judgment of the investigator, could compromise the subject's participation in the study or pose an undue risk.
• Subject's decision to withdraw from the study (withdrawal of informed consent);
• Investigator's decision to discontinue the subject from the study in the subject's best interest;
• Investigator-determined need for a concomitant therapy explicitly prohibited by the protocol of clinical study;
• Subject's use of a therapy prohibited by the protocol;
• Positive urine test for beta-human chorionic gonadotropin (β-hCG) in females of childbearing potential;
• Lack of adequate cooperation by the subject with the investigator during the study;
• Emergence during the study of conditions or events that jeopardize subject safety (e.g., hypersensitivity reactions, serious adverse events \[SAEs\]) or, in the investigator's medical judgment, worsen the subject's prognosis or preclude further participation in the clinical study;
• Major deviation from the treatment regimen, defined as:
• Missing two or more consecutive doses of the investigational medicinal product (IMP) or comparator;
• Total intake of fewer than 80% or more than 120% of the planned total number of capsules (full course includes 10 capsules);
• Confirmed diagnosis of COVID-19;
• Occurrence during the study of any other condition that precludes adherence to the protocol;
• Subject's death.