A Study of S-337395 in Symptomatic Nonhospitalized Adults With Respiratory Syncytial Virus (RSV) Who Are at High Risk of Progression to Severe Disease

Official title

A Phase 2b, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Study to Evaluate the Safety, Tolerability, and Efficacy of S-337395 in Symptomatic Nonhospitalized Adults With Respiratory Syncytial Virus Who Are at High Risk of Progression to Severe Disease

Overview

The main purpose of this study is to investigate the antiviral effect of S-337395 compared with placebo among nonhospitalized adult participants with high-risk factors for progression to severe RSV infection starting intervention within 72 hours of RSV symptom onset.

Interventions

• Drug S-337395
  S-337395 will be administered per schedule specified in the arm description.
• Drug Placebo
  Placebo matched to S-337395 will be administered per schedule specified in the arm description.

Primary outcome measures

• Change From Baseline in RSV Ribonucleic Acid (RNA) Load by Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) (Nasopharyngeal Swab) at Day 2 [Time frame: Baseline, Day 2]
• Change From Baseline in RSV RNA Load by qRT-PCR (Nasopharyngeal Swab) at Day 4 [Time frame: Baseline, Day 4]
• Change From Baseline in RSV RNA Load by qRT-PCR (Nasopharyngeal Swab) at Day 6 [Time frame: Baseline, Day 6]

Secondary outcome measures (12)

• Number of Participants With Treatment-emergent Adverse Events (TEAEs) [Time frame: Day 1 up to Day 28]
• Change From Baseline in Severity of RSV Respiratory Symptom Score Based on the Respiratory Infection Intensity and Impact Questionnaire (RiiQ) Respiratory Symptom Subscale (RiiQ-RSS) [Time frame: Baseline up to Day 6]
• Change From Baseline in Severity of RSV Systemic Symptoms Score Based on the RiiQ Systemic Symptom Subscale (RiiQ-SSS) [Time frame: Baseline up to Day 6]
• Change From Baseline in Severity of RSV Total Symptoms Score Based on the Combined RiiQ RSS and RiiQ-SSS [Time frame: Baseline up to Day 6]
• Time to First Resolution of All Respiratory RSV-related Symptoms Based on the RiiQ-RSS [Time frame: Baseline up to Day 6]
• Time to Sustained (2 Consecutive Days) Resolution of All Respiratory RSV-related Symptoms Based on the RiiQ-RSS [Time frame: Baseline up to Day 6]
• Time to First Resolution of All Systemic RSV-related Symptoms Based on the RiiQ-SSS [Time frame: Baseline up to Day 6]
• Time to Sustained Resolution of All Systemic RSV-related Symptoms Based on the RiiQ-SSS [Time frame: Baseline up to Day 6]
• Time to First Resolution of All Respiratory and Systemic RSV-related Symptoms Based on the Combined RiiQ RSS and RiiQ-SSS [Time frame: Baseline up to Day 6]
• Time to Sustained Resolution of All Respiratory and Systemic RSV-related Symptoms Based on the Combined RiiQ RSS and RiiQ-SSS [Time frame: Baseline up to Day 6]
• Time to First Resolution of Each Separate RSV-related Symptom Based on the RiiQ Symptom Subscale [Time frame: Baseline up to Day 6]
• Time to Sustained Resolution of Each Separate RSV-related Symptom Based on the RiiQ Symptom Subscale [Time frame: Baseline up to Day 6]

Eligibility criteria

Inclusion criteria

• Participants who have new onset or worsening (if present chronically) of at least 1 of the following signs and/or symptoms consistent with a viral acute respiratory infection within 72 hours prior to randomization: fever, nasal congestion, nasal discharge, sore throat, cough, sputum production, shortness of breath, or wheezing.
• Participants diagnosed with RSV infection preferably using a rapid polymerase chain reaction (PCR) or other molecular-based diagnostic assay.
• Has at least 1 of the following risk factors for severe RSV disease:

• ≥ 75 years of age;
• Chronic lung disease that is symptomatic and requiring chronic treatment; and
• Chronic cardiovascular disease that is symptomatic and requiring chronic treatment.
• With the exception of the RSV disease, medically stable on the basis of medical history, physical examination, vital signs, and 12-lead electrocardiogram (ECG) performed at screening.

Exclusion criteria

• Hospitalized or expected to be hospitalized within 24 hours of screening.
• Is considered by the investigator to be immunocompromised, due to an underlying medical condition or medical therapy, chemotherapy, radiation, stem cell or solid organ transplant.
• Has known allergies, hypersensitivity, or intolerance to S-337395 or to any of the excipients of the S-337395 or placebo formulation.
• Suspicion or known severe renal impairment.
• Any other medical or psychiatric condition making the participant unsuitable for the current study or interfering with the evaluation of response to the study intervention in the opinion of the investigator/subinvestigator.
• Has received a therapy intended to treat RSV infection within 14 days prior to screening.
• Is receiving chemotherapy or immunotherapy for malignancy.
• Has received RSV vaccination within 7 days prior to screening.
• Has had either confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or influenza infection (test was positive) during the 28 days prior to screening.
• Has any other confirmed clinically relevant respiratory infection by any pathogen at, or within 28 days of screening.

Note: Other protocol-specified inclusion and exclusion criteria may apply.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Quadruple blind

Primary purpose

Treatment

Study locations

United States · 36 centers

• LA Universal Research Center, Inc. — Los Angeles
• Central Valley Research — Modesto
• Med Partnes, Inc - Elligo- PPDS — Toluca Lake
• Hope Clinical Trials - 3970 W Flagler St. — Coral Gables
• Beautiful Minds Clinical Research Center — Cutler Bay
• Doral Medical Research — Hialeah
• Southern Clinical Research — Miami
• LCC Medical Research - Miami - BTC - PPDS — Miami
• … and 28 more centers

Japan · 29 centers

• Kamezawa Clinic — Kasugai-Shi
• Hosokawa Surgical Clinic — Nagoya-Shi Nakamura-Ku
• Doi Clinic — Chikushino-shi
• Irie Clinic — Fukuoka
• Tomita Internal Medicine Clinic — Fukuoka-Shi Chuo-Ku
• PS Clinic — Fukuoka-Shi Hakata-Ku
• Medical corporation Aimeikai Morizono internal medicine — Kitakyushu-Shi Yahatanishi-Ku
• Social Medical Corporation the Chiyukai foundation Shin Komonji Hospital — Kitakyushu-Shi
• … and 21 more centers

Bulgaria · 5 centers

• Medical Center Hera EOOD, Montana — Montana
• Multiprofile Hospital For Active Treatment Dr Tota Venkova - PRATIA - PPDS — Gabrovo
• MCpulmo-2018 Ltd — Haskovo
• Medical Center Hera EOOD — Sofia
• Medical Center Neuromedics EOOD - 4 Veliki Preslav Str — Veliko Tarnovo

Argentina · 4 centers

• Fundación Huésped - PPDS — CABA
• AES - AS - Glenny Corp. S.A. Buenos Aires — CABA
• Instituto Médico Río Cuarto — Río Cuarto
• AES - AS - Clinica Mayo de Urgencias — San Miguel de Tucumán

South Africa · 4 centers

• Newtown Clinical Research Centre — Johannesburg
• Roodepoort Medicross Clinical Research Centre — Princess Crossing
• Be Part Yoluntu Centre — Paarl
• … and 1 more center

Poland · 3 centers

• Alergo-Med Osrodek Badan Klinicznych sp z o.o — Tarnów
• Centrum Medyczne Chojnice - PRATIA - PPDS — Chojncie
• Ostrowieckie Centrum Medyczne Spólka Cywilna Anna Olech-Cudzik, Krzysztof Cudzik — Ostrowiec Świętokrzyski

Taiwan · 2 centers

Center list to be confirmed — check the primary protocol.

Identifiers

NCT: NCT07214571 · 2402T1432

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗