A Study to Assess EDP-938 for the Treatment of Acute Upper Respiratory Tract Infection With Respiratory Syncytial Virus in Adult Subjects

Inclusion Criteria: * An informed consent document must be signed and dated by the subject * Male or female individuals aged 18 to 75 years, inclusive. * Up to 48 hours of URTI symptoms with at least one of the following symptoms: Nasal discharge, nasal congestion, malaise/tiredness, headache, sinus congestion, sneezing, sore throat, hoarseness, cough, shortness of breath, respiratory wheeze, earache, and/or symptoms of fever. * Positive for RSV infection and negative for influenza virus based on rapid diagnostic. * Must be willing and able to adhere to the study assessments, visit schedules, prohibitions, and restrictions, as described in this protocol. Exclusion Criteria: * SARS-CoV-2 positive within 28 days of Screening or at Screening following signature of full ICF. * Clinical evidence of a lower respiratory tract infection, as determined by the Investigator. * Anticipated need for hospitalization or emergency room care within 24 hours of Screening. * Receipt of systemic antiviral, antibacterial, antifungal, or antimycobacterial therapy within 7 days of Screening and for the duration of the study * Awareness of concomitant respiratory infections that are viral (other than RSV), bacterial, or fungal, including systemic bacterial or fungal infections, within 7 days of Screening. * Frailty scale score ≥4 at Screening. * History of chronic liver disease (eg, hemochromatosis, Wilson's disease, alpha-1 antitrypsin deficiency, autoimmune hepatitis, nonalcoholic steatohepatitis, and/or alcoholic liver disease); a history of biliary disease (eg, primary sclerosing cholangitis, cholecystitis, choledocholithiasis); or a history of portal hypertension. A diagnosis of hepatic steatosis (fatty liver) is not exclusionary. * Heart disease: any congenital heart disease, acute or chronic heart failure, ischemic heart disease, congenital long QT syndrome, or any clinical manifestation resulting in QT interval prolongation. * Neurological and neurodevelopmental disorders (including disorders of the brain, spinal cord, peripheral nerve, and muscle, eg, cerebral palsy, epilepsy \[seizure disorders\], stroke, muscular dystrophy, or spinal cord injury). * Malignant tumor or history of malignancy that may interfere with the aims of the study or a subject completing the study. * Prior receipt or the subject is waiting to receive a bone marrow, stem cell, or solid organ transplantation. * Diagnosis of cystic fibrosis. * Known positive human immunodeficiency virus, active hepatitis A virus infection, chronic hepatitis B virus infection, and/or current or treated hepatitis C virus infection. * Prior or planned ileal resection or bariatric surgery. * Pregnant or nursing female subjects. * History of alcohol addiction or current heavy alcohol use defined as: \>14 standard drinks per week and/or ≥4 standard drinks per occasion for males and \>7 standard drinks per week and/or ≥3 standard drinks per occasion for females. A standard drink is 12 oz of beer (5% alcohol), 5 oz table wine (12% alcohol), or 1.5 oz of spirits (40% alcohol). * Known or suspected, in the opinion of the Investigator, renal disease or renal impairment. * Twelve-lead ECG demonstrating a QT interval corrected for heart rate according to Fridericia (QTcF) that is \>500 msec or other clinically relevant abnormalities as judged by the Investigator at Screening. * Use of or intention to use excluded or contraindicated medication(s) or supplements, including any medication known to be a moderate or potent inducer or inhibitor of the cytochrome P450 3A4 enzyme, within 14 days prior to Screening and for the duration of the study. * Receipt of ≥14 days of systemic immunomodulator therapy (eg, oral corticosteroids) within 3 months of Screening. * Prior to the first dose of study drug and during study participation, the subject has received any vaccine, investigational agent, or biological product within 30 days or 5 times the half-life, whichever is longer. Note: Influenza vaccination within 7 days of Screening is allowed. * Use of St John's wort within 28 days prior to the first dose of study drug and for the duration of the study. * History of or currently experiencing a medical condition or any other finding (including laboratory test results) that, in the opinion of the Investigator, might confound the results of the study; pose an additional risk in administering study drug to the subject; could prevent, limit, or confound the protocol-specified assessments; or deems the subject unsuitable for the study.