Actively Recruiting
A Phase 2b, Randomized, Double-blind, Placebo-controlled Study of S-337395 in Nonhospitalized Adults With RSV at High Risk of Severe Disease
Led by Shionogi · Updated on 2026-05-20
192
Participants Needed
72
Research Sites
N/A
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the antiviral effects of S-337395 compared to placebo in adults who are not hospitalized but have symptomatic Respiratory Syncytial Virus (RSV) infections and are at high risk of developing severe disease. The study focuses on participants who start treatment within 72 hours of RSV symptom onset and aims to better understand how S-337395 impacts viral load and symptom severity. Participants are randomly assigned to one of three groups: a high dose of S-337395 taken orally twice daily for up to 5 days, a low dose of S-337395 taken with the same schedule, or a matching placebo taken twice daily for 5 days. This study is a phase 2b, multicenter, randomized, double-blind, placebo-controlled trial designed to assess safety, tolerability, and effectiveness of the drug. Throughout the study, participants will have nasopharyngeal swabs to measure RSV RNA levels at several points: baseline, day 2, day 4, and day 6. They will also report symptom severity using questionnaires covering respiratory and systemic symptoms up to day 6. Researchers will monitor adverse events up to 28 days and measure drug concentrations in plasma. The total participation includes treatment and follow-up assessments to evaluate the impact of S-337395 on RSV infection progression.
CONDITIONS
Brief Title
A Study of S-337395 in Symptomatic Nonhospitalized Adults With Respiratory Syncytial Virus (RSV) Who Are at High Risk of Progression to Severe Disease
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Adults 18 years or older
- New or worsening viral respiratory infection symptoms within 72 hours before randomization
- Confirmed RSV infection, preferably by rapid PCR or molecular test
- At least one risk factor: age 75 or older, chronic lung disease requiring treatment, or chronic cardiovascular disease requiring treatment
- Medically stable except for RSV infection based on medical history, exam, vital signs, and ECG
You will not qualify if you...
- Hospitalized or expected hospitalization within 24 hours of screening
- Immunocompromised due to medical condition or therapy
- Known allergies or intolerance to S-337395 or its components
- Severe renal impairment suspected or known
- Other medical or psychiatric conditions interfering with study participation
- Received RSV treatment within 14 days before screening
- Receiving chemotherapy or immunotherapy for cancer
- RSV vaccination within 7 days before screening
- Confirmed SARS-CoV-2 or influenza infection within 28 days before screening
- Other confirmed respiratory infections within 28 days before screening
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - Up to 5 days
Participants receive S-337395 or placebo orally twice daily for up to 5 days to treat RSV infection.
Daily visits or contacts for up to 6 days including baseline and follow-up assessments
Duration - Up to 28 days from Day 1
Participants are monitored for safety and symptom resolution after treatment completion.
Scheduled visits or contacts through Day 28
Trial Site Locations
Total: 72 locations
1
LA Universal Research Center, Inc.
Los Angeles, California, United States, 900057-4040
Actively Recruiting
2
Med Partnes, Inc - Elligo- PPDS
Toluca Lake, California, United States, 91602-3457
Actively Recruiting
3
Hope Clinical Trials - 3970 W Flagler St.
Coral Gables, Florida, United States, 33134-1642
Actively Recruiting
4
Beautiful Minds Clinical Research Center
Cutler Bay, Florida, United States, 33157
Actively Recruiting
5
Doral Medical Research
Hialeah, Florida, United States, 33016-1897
Actively Recruiting
6
Southern Clinical Research
Miami, Florida, United States, 33125-4106
Actively Recruiting
7
LCC Medical Research - Miami - BTC - PPDS
Miami, Florida, United States, 33126
Actively Recruiting
8
Global Health Clinical Trials
Miami, Florida, United States, 33135-2961
Actively Recruiting
9
Nuren Medical and Research Center
Miami, Florida, United States, 33144-2069
Actively Recruiting
10
Continental Clinical Research, LLC
Miami, Florida, United States, 33144-4273
Actively Recruiting
11
Dynamic Medical Research, LLC - Miami
Miami, Florida, United States, 33144
Actively Recruiting
12
Miami Clinical Research, LLP.
Miami, Florida, United States, 33155
Actively Recruiting
13
Reed Medical Research
Miami, Florida, United States, 33176-8709
Actively Recruiting
14
Palm Springs Community Health Center
Miami Lakes, Florida, United States, 33014-2266
Actively Recruiting
15
Oceanic Research Group, LLC
North Miami Beach, Florida, United States, 33169-5513
Actively Recruiting
16
CDC Research Institute, LLC
Port Saint Lucie, Florida, United States, 34952-7539
Actively Recruiting
17
Cordova Research Insittute
Sweetwater, Florida, United States, 33182
Actively Recruiting
18
Better Life Clinical Research LLC
Tampa, Florida, United States, 33607
Actively Recruiting
19
Research Bay,Inc.
Tampa, Florida, United States, 33607
Actively Recruiting
20
Santos Research Center - 5927 Webb Rd
Tampa, Florida, United States, 33615-3219
Actively Recruiting
21
Angels Clinical Research Institute Tampa-Palm Springs
Tampa, Florida, United States, 336214-2869
Actively Recruiting
22
Covenant Pulmonary Criticial Care and Research Ins
East Point, Georgia, United States, 30344-3604
Actively Recruiting
23
Clay Platte Family Medicine - CCT Research
Kansas City, Missouri, United States, 64151-2411
Actively Recruiting
24
NYC Health + Hospitals/Lincoln Medical Center - BRANY - PPDS
The Bronx, New York, United States, 10451
Actively Recruiting
25
Prime Global Research, Inc.
The Bronx, New York, United States, 10456-2102
Actively Recruiting
26
Progressive Medicine of the Triad, LLC
Winston-Salem, North Carolina, United States, 27103
Actively Recruiting
27
University Hospitals Cleveland Medical Center
Cleveland, Ohio, United States, 44106
Actively Recruiting
28
Epic Medical Research - Chickasha
Chickasha, Oklahoma, United States, 73018-2738
Actively Recruiting
29
Rhode Island Hospital
Providence, Rhode Island, United States, 02903-4923
Actively Recruiting
30
Epic Med. Research LLC, DeSoto
DeSoto, Texas, United States, 75115-2043
Actively Recruiting
31
SMS Clinical Research, LLC - 400 W. Kearney St
Mesquite, Texas, United States, 751497
Actively Recruiting
32
Clinical Research Partners LLC
Richmond, Virginia, United States, 23226-3786
Actively Recruiting
33
Frontier Clinical Research Waterfront
Morgantown, West Virginia, United States, 26501
Actively Recruiting
34
Medical Center Hera EOOD, Montana
Montana, Sofia, Bulgaria, 3400
Actively Recruiting
35
Multiprofile Hospital For Active Treatment Dr Tota Venkova - PRATIA - PPDS
Gabrovo, Bulgaria, 5300
Actively Recruiting
36
MCpulmo-2018 Ltd
Haskovo, Bulgaria, 6300
Actively Recruiting
37
Medical Center Hera EOOD
Sofia, Bulgaria, 1510
Actively Recruiting
38
Medical Center Neuromedics EOOD - 4 Veliki Preslav Str
Veliko Tarnovo, Bulgaria, 5005
Actively Recruiting
39
Kamezawa Clinic
Kasugai-Shi, Aiti, Japan, 0568-56-5050
Actively Recruiting
40
Hosokawa Surgical Clinic
Nagoya-Shi Nakamura-Ku, Aiti, Japan, 052-481-9921
Actively Recruiting
41
Doi Clinic
Chikushino-shi, Fukuoka, Japan, 092-926-7415
Actively Recruiting
42
Irie Clinic
Fukuoka, Fukuoka, Japan, 092-651-4521
Actively Recruiting
43
Tomita Internal Medicine Clinic
Fukuoka-Shi Chuo-Ku, Fukuoka, Japan, 092-707-2103
Actively Recruiting
44
PS Clinic
Fukuoka-Shi Hakata-Ku, Fukuoka, Japan, 092-283-7777
Actively Recruiting
45
Medical corporation Aimeikai Morizono internal medicine
Kitakyushu-Shi Yahatanishi-Ku, Fukuoka, Japan, 093-611-5335
Actively Recruiting
46
Social Medical Corporation the Chiyukai foundation Shin Komonji Hospital
Kitakyushu-Shi, Fukuoka, Japan, 093-391-1001
Actively Recruiting
47
Shizuka Clinic
Takasaki-shi, Gunma, Japan, 027-370-0777
Actively Recruiting
48
Social medical corporation Keiwakai Nishioka Hospital
Sapporo-Shi Toyohira-Ku, Hokkaidô, Japan, 011-853-8322
Actively Recruiting
49
Terada Internal Medicine and Respiratory Department
Himeji-shi, Hyôgo, Japan, 079-285-0111
Actively Recruiting
50
Tsuchiura Beryl Clinic
Tsuchiura-Shi, Ibaraki, Japan, 029-835-3002
Actively Recruiting
51
Gajyumaru Clinic Tsukuba
Tsukuba, Ibaraki, Japan, 029-893-4159
Actively Recruiting
52
Shiwa Central Pediatrics
Shiwa-gun, Iwate, Japan, 019-672-1110
Actively Recruiting
53
Medical corporation Kojinkai Takahashi Internal Medicine
Kawasaki-Shi, Kanagawa, Japan, 044-740-2717
Actively Recruiting
54
Ebino Centro Clinic
Ebino, Miyazaki, Japan, 0984-33-5777
Actively Recruiting
55
Rinku General Medical Center
Izumisano, Osaka, Japan, 072-469-3111
Actively Recruiting
56
Yamaichi Building Internal Medicine Clinic
Adachi-Ku, Tokyo, Japan, 03-884-8888
Actively Recruiting
57
Medical Corporation Hosoda Clinic
Katsushika-ku, Tokyo, Japan, 03-3657-3430
Actively Recruiting
58
Medical Corporation Shirayurikai Swing Building Nozaki Clinic
Musashino, Tokyo, Japan, 0422-36-3534
Actively Recruiting
59
Nogata Clinic
Nakano-ku, Tokyo, Japan, 03-3389-2201
Actively Recruiting
60
Noguchi Internal Medicine Clinic
Nakano-Ku, Tokyo, Japan, 03-3926-0007
Actively Recruiting
61
Sato Clinic
Shibuya-Ku, Tokyo, Japan, 03-5447-2477
Actively Recruiting
62
Mih Clinic Yoyogi
Shibuya-Ku, Tokyo, Japan, 03-6276-5385
Actively Recruiting
63
Medical corporation Hiroyukai Yotsuya Internal Medicine
Shinjuku-Ku, Tokyo, Japan, 03-5368-0675
Actively Recruiting
64
Yoshida Clinic
Suginami-ku, Tokyo, Japan, 03-5347-7300
Actively Recruiting
65
Sekino Hospital
Toshima-Ku, Tokyo, Japan, 03-3986-5501
Actively Recruiting
66
Kijima Kids Clinic
Higashiokitama-gun, Yamagata, Japan, 0238-54-0135
Actively Recruiting
67
Toda Internal Medicine and Neurology
Hyōgo, Japan, 078-947-5575
Actively Recruiting
68
Alergo-Med Osrodek Badan Klinicznych sp z o.o
Tarnów, Lesser Poland Voivodeship, Poland, 33-100
Actively Recruiting
69
Centrum Medyczne Chojnice - PRATIA - PPDS
Chojncie, Pomeranian Voivodeship, Poland, 86-900
Actively Recruiting
70
Ostrowieckie Centrum Medyczne Spólka Cywilna Anna Olech-Cudzik, Krzysztof Cudzik
Ostrowiec Świętokrzyski, Świętokrzyskie Voivodeship, Poland, 27-400
Actively Recruiting
71
Newtown Clinical Research Centre
Johannesburg, Gauteng, South Africa, 2001
Actively Recruiting
72
Be Part Yoluntu Centre
Paarl, Western Cape, South Africa, 7655
Actively Recruiting
Research Team
S
Shionogi Clinical Trials Administrator Clinical Support Help Line
How is the study designed?
Study Type
INTERVENTIONAL
Masking
QUADRUPLE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
TREATMENT
Number of Arms
3
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