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A Study to Learn About the Study Medicine Sisunatovir in Adults With Respiratory Syncytial Virus (RSV) Infection

Phase 2
Terminated
Conditions
Respiratory Syncytial Virus Infection
Interventions
Drug: Placebo
Registration Number
NCT06079320
Lead Sponsor
Pfizer
Brief Summary

The purpose of this study is to learn about the safety and effects of sisunatovir. Sisunatovir is studied for the possible treatment of Respiratory Syncytial Virus (RSV). RSV is a virus that causes lung infections with cold-like symptoms, but it can cause severe illness in some people. Sisunatovir is studied in adults:

* who are not admitted to the hospital and

* who have high chances of having a severe illness from RSV infection.

This study is seeking participants who:

* Are confirmed to have RSV.

* Have symptoms of a lung infection.

* Are 18 years of age or older.

* Have one or more of the following which increases the chances of RSV illness:

* A long-term lung disease.

* heart failure.

* a condition that weakens the immune system.

* Are 65 years of age or older and do not have any of the conditions above

Half of the participants in this study will receive sisunatovir. The other half will receive a placebo for 5 days. Placebo looks same like the study medicine but does not have any medication. Both sisunatovir and placebo will be taken by mouth. The study will compare the experiences of people receiving sisunatovir to those of the people who do not. This will help decide if sisunatovir is safe and effective.

Participants will attend about 8-10 study visits over 5 weeks. During this time, they will have:

* visits at the study clinic,

* blood work,

* swabs of the nose,

* questionnaires,

* a follow-up phone call.

Detailed Description

Not available

Recruitment & Eligibility

Status
TERMINATED
Sex
All
Target Recruitment
16
Inclusion Criteria
  • Participants aged 18 years or older at screening.
  • Diagnosis of RSV infection collected within 5 days prior to randomization.
  • New onset or worsening (if present chronically) of at least one of the following signs and/or symptoms consistent with a viral acute respiratory infection (ARI), within 5 days prior to randomization: nasal congestion, nasal discharge, sore throat, cough, sputum production, shortness of breath, or wheezing.
  • Has at least 1 of the following characteristics or underlying medical conditions: a) 65 years of age or older b) Chronic lung disease, c) Heart failure, d) Immunosuppressive disease/condition or immune-weakening medications
Exclusion Criteria
  • Any medical or psychiatric condition that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study or interfere with the evaluation of response to the study intervention.
  • Diagnosis of viral respiratory infections other than RSV including influenza and SARS-CoV-2
  • Current need for hospitalization or anticipated need for hospitalization for any reason to provide inpatient/acute care within 24 hours after randomization
  • Any clinically significant ECG abnormality in the pre-dose ECG that, per investigator judgement, may affect participant safety
  • Has hypersensitivity to or other contraindication to any of the components of the study interventions, as determined by the investigator.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlacebo-
SisunatovirSisunatovir-
Primary Outcome Measures
NameTimeMethod
Number of Participants With Respiratory Syncytial Virus (RSV) Related Hospitalization or Death From Any Cause Through Day 28From Day 1 (start of study intervention) up to Day 28

RSV related hospitalization included a specialized acute medical care unit within an assisted living facility or nursing home.

Secondary Outcome Measures
NameTimeMethod
Number of Participants With RSV-Related Visits (Urgent Care/ Emergency Department (ED)/Hospital) or Death From Any Cause Through Day 28From Day 1 (start of study intervention) up to Day 28

Participants with RSV related visits in a hospital/urgent care or ED requiring no minimum duration of hospitalization were reported in this outcome measure. Investigators determined if a medical visit was related to RSV. RSV-related medical visits were those attendances that would not otherwise occur in the absence of the RSV infection. These may have included: deterioration or decompensation of the lung function that required supplemental oxygen; development of secondary respiratory tract infections that required antibiotic treatment; management of severe symptoms associated with RSV such as fever; worsening or decompensation of cardiac or renal function in participants with underlying cardiac or renal disease.

Number of Participants With Progression of Lower Respiratory Tract Infection (LRTI) Through Day 10From randomization on Day 1 up to Day 10

Progression of LRTI was defined as development of LRTI or transition from non-severe LRTI-RSV at randomization to severe LRTI-RSV at any time up to and including Day 10. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 less than (\<) 95 percent (%) or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Number of Participants With Development of LRTI Through Day 10From randomization on Day 1 up to Day 10

Development of LRTI was defined as transitioning from not having LRTI at randomization but having nsLRTI-RSV or sLRTI-RSV at any time up to and including Day 10. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95 % or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Number of Participants With Resolution of LRTI at Day 15Day 15

Resolution of LRTI was defined as transition from RSV-related non-severe LRTI (nsLRTI-RSV) or RSV-related severe LRTI (sLRTI-RSV) at randomization to not having nsLRTI and sLRTI-RSV. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95 % or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Mean Number of Hospital Free Days Through Day 28From Day 1 (start of study intervention) up to Day 28
Number of Participants With Progression of LRTI Through Days 3, 5, 15 and 28From randomization on Day 1 up to Days 3, 5, 15 and 28

Progression of LRTI was defined as development of LRTI or transition from non severe LRTI-RSV at randomization to severe LRTI-RSV at any time up to and including Days 3, 5, 15 and 28. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95 % or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Number of Participants With Development of LRTI Through Days 3, 5, 15 and 28From randomization on Day 1 up to Days 3, 5, 15 and 28

Development of LRTI was defined as transitioning from not having LRTI at randomization but having nsLRTI-RSV or sLRTI-RSV at any time up to and including Days 3, 5, 15 and 28. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95 % or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Number of Participants With Resolution of LRTI at Days 3, 5, 10 and 28At Days 3, 5, 10 and 28

Resolution of LRTI was defined as transition from nsLRTI-RSV or sLRTI-RSV at randomization to not having nsLRTI and sLRTI-RSV. LRTI was defined as \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95% or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Number of Participants With Improvement of LRTI at Days 3, 5, 10, 15 and 28At Days 3, 5, 10, 15 and 28

Improvement in LRTI status was defined as LRTI resolution or transition from sLRTI-RSV at randomization to nsLRTI-RSV. LRTI was defined as: \>= 2 lower respiratory signs or symptoms for at least 24 hours including at least 1 lower respiratory sign; or 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included following: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, new or increased crackles/ronchi based on chest auscultation, respiratory rate \>= 20 respirations/minute, low or decreased oxygen saturation (O2 \< 95 % or \<= 90% if pre-season baseline is \< 95%), need for new or increased oxygen supplementation.

Mean Number of RSV Related Days in Hospital Through Day 28From Day 1 (start of study intervention) up to Day 28

RSV related hospitalization included a specialized acute medical care unit within an assisted living facility or nursing home.

Mean Number of RSV Related Days in Intensive Care Unit (ICU) Through Day 28From Day 1 (start of study intervention) up to Day 28
Number of Participants With a Clinical Response of Improvement or Resolution at Days 5, 10, 15, and 28At Days 5, 10, 15, and 28

Improvement was defined as no new acute respiratory infection (ARI) signs or symptoms, and no worsening of existing signs or symptoms compared to the Day 1 visit. At least one sign or symptom (but not all) present at Day 1 was absent, improved or returned to pre-infection status. Resolution was defined as all ARI signs or symptoms were absent or returned to pre-infection status. Clinical response was evaluated by the investigator.

Number of Participants With Undetectable RSV Viral Load at Days 3, 5, 10, 15 and 28At Days 3, 5, 10, 15, and 28

Undetectable RSV viral load at a visit was defined as a central PCR laboratory result of target not detected (TND).

Change From Baseline in Log10 Transformed Total RSV Viral Load at Days 3, 5, 10, 15 and 28Baseline (within 1 hour post start of study intervention on Day 1) and Days 3, 5, 10, 15, and 28

Undetectable viral load was considered to be 0 copies/mL for this analysis.

Number of Participants With Treatment Emergent Adverse Events (TEAEs) Through Day 35From Day 1 of study intervention up to 28-30 days after last dose of study drug (up to Day 35)

An AE was any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An adverse event was considered a TEAE if the event started on or after the study intervention start date (Day 1).

Number of Participants With Treatment Emergent Serious Adverse Events (TESAE) Through Day 35From Day 1 of study intervention up to 28-30 days after last dose of study drug (up to Day 35)

An SAE was defined as any untoward medical occurrence that, at any dose, met one or more of the criteria listed below: resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, suspected transmission via a Pfizer product of an infectious agent, pathogenic or nonpathogenic and other important medical event.

Plasma Concentrations of Sisunatovir at Days 3 and 5Anytime between 3 to 8 hours post dose on Day 3, and pre-dose on Day 5

Trial Locations

Locations (18)

National Institute of Clinical Research

🇺🇸

Westminster, California, United States

De La Cruz Research Center, LLC

🇺🇸

Miami, Florida, United States

Adult Medicine of Lake County, Inc.

🇺🇸

Mt. Dora, Florida, United States

Adult Medicine of Lake County

🇺🇸

Mt. Dora, Florida, United States

Accellacare - DuPage

🇺🇸

Oak Lawn, Illinois, United States

Mercury Street Medical Group, PLLC

🇺🇸

Butte, Montana, United States

DM Clinical Research - AOM

🇺🇸

Brooklyn, New York, United States

CHEAR Center LLC

🇺🇸

The Bronx, New York, United States

Preferred Primary Care Physicians, Preferred Clinical Research (Ofc 18)

🇺🇸

Pittsburgh, Pennsylvania, United States

Zenos Clinical Research

🇺🇸

Dallas, Texas, United States

Scroll for more (8 remaining)
National Institute of Clinical Research
🇺🇸Westminster, California, United States

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