Assessing Antiviral Treatments in Early Symptomatic RSV

This trial will use a previously validated platform, to quantitatively assess antiviral effects in low-risk patients with high viral burdens and uncomplicated Respiratory Syncytial Virus (RSV), to determine in-vivo antiviral activity. In this randomised, open-label, controlled, group sequential adaptive platform trial, we will assess and compare the performance of currently licensed interventions (including repurposed drugs) with activity against RSV, and those with potential activity demonstrated in pre-clinical and early clinical studies relative to each-other, and the control (no antiviral treatment). ARSYNAL-FC study is funded by Wellcome Trust Grant ref: 226933/Z/23/Z through the COVID-19 Therapeutics Accelerator

There are no proven effective drug treatments for RSV. While vaccines are becoming available, and monoclonal antibodies exist for prevention in infants, antiviral treatments are still urgently needed. The study is a randomised, open label, controlled, adaptive platform trial that will be conducted in low-risk adult patients (18 - \<65 years old) with early symptomatic RSV, recruited from outpatient acute respiratory infection clinics (ARIs), other approved facilities, or by patient self-referral to the study site. The primary pharmacodynamic measure in this study is the rate of viral clearance following treatment. Individual patient's involvement for this study is 28 days. This platform will compare antivirals with potential RSV antiviral activity, against a negative control (no treatment). Currently, interventions included in the platform are; * Interventions licensed for paediatric RSV infections: ribavirin. * Interventions with antiviral activity against RSV demonstrated in in-vitro studies: molnupiravir and favipiravir Randomisation to the no antiviral treatment control arm (no intervention) will be fixed at a minimum of 20% throughout the study. The randomisation ratios will be uniform for all available interventions.