S-337395 / Shionogi, Ube Corp - LARVOL DELTA

Phase 2a Randomized Placebo-Controlled Human Challenge Trial of the RSV L-Protein Inhibitor S-337395 for Respiratory Syncytial Virus Infection. (PubMed, Clin Infect Dis) - "S-337395 significantly reduced viral load, viral titer, and symptoms, and was well-tolerated in this human challenge study."

Clinical • Journal • P2a data • Infectious Disease • Respiratory Diseases • Respiratory Syncytial Virus Infections

2402T1432: Phase 2b study of S-337395 in symptomatic nonhospitalized adults with respiratory nsyncytial virus (RSV) who are at high risk of progression to severe disease (clinicaltrialsregister.eu) - P1/2 | N=19 | Recruiting | Sponsor: Shionogi B.V. | Not yet recruiting ➔ Recruiting

Enrollment open • Respiratory Diseases • Respiratory Syncytial Virus Infections

2402T1432: Phase 2b study of S-337395 in symptomatic nonhospitalized adults with respiratory nsyncytial virus (RSV) who are at high risk of progression to severe disease (clinicaltrialsregister.eu) - P1/2 | N=15 | Not yet recruiting | Sponsor: Shionogi B.V.

New P1/2 trial • Respiratory Diseases • Respiratory Syncytial Virus Infections

Pharmacokinetic/Pharmacodynamic Analysis of S-337395, a Novel RSV L-Protein Inhibitor, in a Human Challenge Study (RSVVW 2026) - "Solid line represents the predicted Emax model curve. Shaded area represents 95% confidence interval of the model prediction.) S-337395 exhibited clear concentration-dependent antiviral activity against RSV infection."

PK/PD data • Infectious Disease • Respiratory Diseases • Respiratory Syncytial Virus Infections

Respiratory syncytial virus in high-risk adults: A critical appraisal of therapeutic options and unmet needs. (PubMed, Respir Med) - "At present, ribavirin remains the only antiviral recommended for treatment in adults, and no mAb has received regulatory authorization for prophylaxis or therapy in this population...Nevertheless, newer drug candidates, including ziresovir, EDP-938, and S-337395, have shown encouraging antiviral activity and acceptable safety in adult studies. By examining both the scientific evidence and the structural factors shaping the current landscape, we emphasize the need for sustained adult-focused clinical development to complement preventive vaccination. Addressing this therapeutic gap will be essential to reduce the burden of RSV disease in high-risk adult populations, particularly as the global population ages."

Journal • Review • Infectious Disease • Pediatrics • Respiratory Diseases • Respiratory Syncytial Virus Infections

A Study of S-337395 in Symptomatic Nonhospitalized Adults With Respiratory Syncytial Virus (RSV) Who Are at High Risk of Progression to Severe Disease (clinicaltrials.gov) - P2 | N=192 | Recruiting | Sponsor: Shionogi | Not yet recruiting ➔ Recruiting

Enrollment open • Infectious Disease • Respiratory Diseases • Respiratory Syncytial Virus Infections

A Study of S-337395 in Symptomatic Nonhospitalized Adults With Respiratory Syncytial Virus (RSV) Who Are at High Risk of Progression to Severe Disease (clinicaltrials.gov) - P2 | N=192 | Not yet recruiting | Sponsor: Shionogi

New P2 trial • Infectious Disease • Respiratory Diseases • Respiratory Syncytial Virus Infections

A Study to Investigate Different Formulations of S-337395 in Healthy Adult Participants (clinicaltrials.gov) - P1 | N=50 | Completed | Sponsor: Shionogi | Recruiting ➔ Completed

Trial completion

A Study to Investigate Different Formulations of S-337395 in Healthy Adult Participants (clinicaltrials.gov) - P1 | N=50 | Recruiting | Sponsor: Shionogi | Not yet recruiting ➔ Recruiting

Enrollment open

A Study to Investigate Different Formulations of S-337395 in Healthy Adult Participants (clinicaltrials.gov) - P1 | N=50 | Not yet recruiting | Sponsor: Shionogi

New P1 trial