A phase 2a study to evaluate EDP-323 in the virus challenge model

INTERVENTION: Participants will be randomized 1:1:1 into one of three treatment groups to receive EDP‐323 (at two different doses) or placebo. EDP‐323 will be administered orally. The interventions selected for this study are as follows: Dose 1 EDP‐323 once daily for 5 days Dose 2 EDP‐323 once daily for 5 days Placebo once daily for 5 days CONDITION: Respiratory Syncytial Virus (RSV) infection ; Infections and Infestations PRIMARY OUTCOME: Reduction in RSV area under the viral load‐time curve (VL‐AUC) measured by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) from the first viral load measurement post initial dose of EDP‐323 or placebo through day 12. SECONDARY OUTCOME: 1. Change in viral load measurements by qRT‐PCR from the first viral load measurement post initial dose of EDP‐323 or placebo through day 12. ; 2. Change in viral load measurements by cell culture (plaque assay) from the first viral load measurement post initial dose of EDP‐323 or placebo through day 12. ; 3. Change of baseline symptoms measured by total symptom score (TSS) and nasal discharge produced post initial dose of EDP‐323 or placebo through Day 12.; 4. Pharmacokinetics:; 4.1. EDP‐323 (and metabolites) concentrations and PK parameters in blood samples: maximum plasma concentration (Cmax), time to maximum plasma concentration (tmax), terminal half‐life (t1/2), apparent systemic clearance (CL/F), terminal elimination rate constant (?z), volume of distribution (Vd/F), plasma concentration at 12 hours (C12h), plasma concentration at 24 hours (C24h), area under the concentration time curve from time 0 to time of last quantifiable concentration (AUClast), area under the concentration time curve over the dosing interval (AUC0‐tau), and area under the concentration time curve from time 0 to infinity (AUC0‐8); 4.2. Plasma PK (area under the curve [AUC]) correlations with VL‐AUC (e.g., qRT‐PCR) and TSS‐AUC; 5. Safety assessed by the occurrence of AEs/SAEs from initial administration of EDP‐323 or placebo through Day 28 INCLUSION CRITERIA: 1. Written Informed Consent 2. Aged 18‐55 years on the day prior to signing the consent form. 3. A total body weight =50 kg and body mass inde X(BMI) =18 kg/m² and =35 kg/m² 4. Participants must be in good health with no history, or current evidence, of clinically significant medical conditions, and no clinically significant test abnormalities that will interfere with participants' safety, as defined by medical history, physical examination, (including vital signs), ECG, and routine laboratory tests as determined by the Investigator 5. Documented medical history either prior to entering the study or following medical history review with the study physician at screening. 6.1. Females of childbearing potential must have a negative pregnancy test prior to enrolment. 6.2. Females of non‐childbearing potential: 6.2.1. Postmenopausal females defined as amenorrhea for 12 months or greater with no alternative medical cause. A high follicle‐stimulating