Efficacy and Safety of Norketotifen in Uncomplicated Influenza-like Illness

Inclusion criteria

• Able to understand the study and comply with all study procedures, and willing to provide written informed consent prior to the pre-dose examinations
• Symptoms of ILI including all of the following:

• Fever ≥38º Celsius (oral)
• At least one of the following general systemic symptoms associated with ILI are present with a severity of moderate or greater: headache, feverishness or chills, muscle or joint pain, fatigue
• At least one of the following respiratory symptoms associated with ILI are present with a severity of moderate or greater: cough, sore throat, nasal congestion
• Total symptom severity score (sum of the scores of all 7 individual symptoms) of ≥11 in the predose examinations
• The time interval between the onset of symptoms and the predose examinations is ≤48 hours.
• Females of childbearing potential and males agree to use an appropriate method of contraception as detailed in the protocol

Exclusion criteria

• Known or suspected infection with Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV2) or Coronavirus Disease 2019 (COVID-19) illness
• Female subjects who are pregnant, 2 weeks post-partum, or breastfeeding
• Severe ILI requiring inpatient treatment
• Any of the following risk factors (according to the CDC's list of People at High Risk for Developing Serious Flu-Related Complications):

• Extreme obesity (body mass index ≥40 kg/m^2)
• Residents of nursing homes or other long-term care facilities
• American Indians and Alaska natives
• Asthma
• Chronic lung disease (such as chronic obstructive pulmonary disease or cystic fibrosis)
• Neurological and neurodevelopmental conditions (including disorders of the brain, spinal cord, peripheral nerve, and muscle such as cerebral palsy, epilepsy [seizure disorders], stroke, intellectual disability, moderate to severe developmental delay, muscular dystrophy, or spinal cord injury)
• Heart disease (such as congenital heart disease, congestive heart failure, or coronary artery disease)
• Blood disorders (such as sickle cell disease)
• Endocrine disorders (such as diabetes mellitus)
• Kidney disorders
• Liver disorders
• Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders)
• Compromised immune system due to disease or medication (such as subjects with human immunodeficiency virus or cancer, or those on chronic steroids)
• Presence of any severe or uncontrolled medical or psychiatric illness
• History of or current autoimmune disease
• History of recurrent lower respiratory tract infection
• Any concurrent infection requiring systemic antimicrobial and/or antiviral therapy
• Any clinically significant electrocardiogram (ECG) test
• Received baloxavir, oseltamivir, peramivir, zanamivir, rimantadine, or amantadine within 30 days prior to the predose examinations
• Received an investigational monoclonal antibody for a viral disease in the last year prior to the predose examinations
• Received ketotifen fumarate, cromolyn sodium, or nedocromil sodium by any route of administration within 30 days prior to the predose examinations
• Exposure to an investigational drug within 30 days prior to the predose examinations
• History of allergic reaction to ketotifen
• Any prior exposure to norketotifen