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Efficacy and Safety of Clesrovimab (MK-1654) in Infants (MK-1654-004)

Phase 2
Completed
Conditions
Respiratory Syncytial Virus Infection
Interventions
Registration Number
NCT04767373
Lead Sponsor
Merck Sharp & Dohme LLC
Brief Summary

The primary objectives of this phase 2b/3 double-blind, randomized, placebo-controlled study are to evaluate the efficacy and safety of clesrovimab in healthy pre-term and full-term infants. It is hypothesized that clesrovimab will reduce the incidence of respiratory syncytial virus (RSV)-associated medically attended lower respiratory infection (MALRI) from Days 1 through 150 postdose compared to placebo.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
3632
Inclusion Criteria
  • Is a healthy male or female who is an early or moderate pre-term infant (≥29 to 34 weeks and 6 days gestational age) or a late pre-term or full-term infant (≥35 weeks gestational age)
  • For the phase 2b cohort only: Has a chronological age >2 weeks of age up to 1 year and is entering their first respiratory syncytial virus (RSV) season at the time of obtaining documented informed consent.
  • For the phase 3 cohort only: Has a chronological age from birth up to 1 year and is entering their first RSV season at the time of obtaining documented informed consent.
  • For participants in South Korea only: Weighs ≥2 kg

Key

Exclusion Criteria
  • Is recommended to receive palivizumab per local guidelines or professional society recommendations.
  • Has known hypersensitivity to any component of clesrovimab
  • Has a bleeding disorder contraindicating IM administration
  • Has had a recent illness with rectal temperature ≥100.5°F (≥38.1°C) or axillary temperature ≥100.0°F (≥37.8°C) within 72 hours predose
  • Has received any vaccine or monoclonal antibody for the prevention of RSV
  • Is currently participating in or has participated in an interventional clinical study with an investigational compound or device at any time before first dose administration or while participating in this study

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PlaceboPlaceboParticipants receive a single IM administration of placebo on Day 1. An eligible subset of participants from RSV Season 1 will enter RSV season 2.
Clesrovimab 105 mgClesrovimabParticipants receive a single intramuscular (IM) administration of clesrovimab 105 mg on Day 1. An eligible subset of participants from RSV Season 1 will enter RSV season 2.
Primary Outcome Measures
NameTimeMethod
RSV Season 1: Number of Participants With Respiratory Syncytial Virus (RSV)-Associated Medically Attended Lower Respiratory Infection (MALRI)From Day 1 (postdose) to Day 150

Outpatient and inpatient MALRI was defined as the presence of the following in a clinical setting: 1) cough or difficulty breathing; AND 2) 1 or more of wheezing, chest wall in-drawing/retraction, rales/crackles, hypoxemia, tachypnea, or dehydration due to respiratory symptoms; AND 3) RSV-positive reverse transcriptase polymerase chain reaction (RT-PCR) nasopharyngeal sample. Per protocol, the participants with outpatient and inpatient RSV-associated MALRI were reported together for RSV season 1 participants.

RSV Season 1: Percentage of Participants With Solicited Injection-Site Adverse Events (AEs)From Day 1 (postdose) to Day 5

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. Solicited injection-site AEs included redness/erythema, swelling, and pain/tenderness. Per protocol, the percentage of RSV season 1 participants with solicited injection-site AEs were reported.

RSV Season 1: Percentage of Participants With FeverFrom Day 1 (postdose) to Day 5

Fever was defined as rectal temperature ≥102.2°F (≥39.0°C) or axillary temperature ≥101.7°F (≥38.7°C). Per protocol, the percentage of RSV season 1 participants with fever were reported.

RSV Season 1: Percentage of Participants With Solicited Systemic AEsFrom Day 1 (postdose) to Day 5

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. Solicited systemic AEs included irritability, somnolence/drowsiness, and appetite lost. Per protocol, the percentage of RSV season 1 participants with solicited systemic AEs were reported.

RSV Season 1: Percentage of Participants With Anaphylaxis/Hypersensitivity AE of Special Interest (AESI)From Day 1 (postdose) to Day 42

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. Anaphylaxis/Hypersensitivity AESI included anaphylaxis, angioedema, bronchospasm, drug hypersensitivity, dyspnea, hypersensitivity, dysphonia, and wheezing. Per protocol, the percentage of RSV season 1 participants with anaphylaxis/hypersensitivity AESI were reported.

RSV Season 1: Percentage of Participants With Rash AESIFrom Day 1 (postdose) to Day 42

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. Rash AESI included acute generalized exanthematous pustulosis, drug eruption, drug reaction with eosinophilia and systemic symptoms, erythema multiforme, generalized rash of exfoliative nature, Stevens-Johnson syndrome, toxic epidermal necrolysis, and urticaria. Per protocol, the percentage of RSV season 1 participants with rash AESI were reported.

RSV Season 1: Percentage of Participants With ≥1 Nonserious AEFrom Day 1 (postdose) to Day 42

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. Per protocol, the percentage of RSV season 1 participants with ≥1 nonserious AE were reported.

Percentage of Participants With Serious Adverse Events (SAEs)RSV Season 1: Day 1 to Day 365, RSV Season 2: Day 366 to Day 515

An SAE was any untoward medical occurrence that results in death; is life-threatening; required inpatient hospitalization/prolongs existing hospitalization; results in persistent or significant disability/incapacity; is a congenital anomaly/birth defect; or other important medical event. Per protocol, the percentage of participants in RSV season 1 and RSV season 2 with SAEs were reported.

Secondary Outcome Measures
NameTimeMethod
RSV Season 1: Number of Participants With RSV-Associated HospitalizationFrom Day 1 (postdose) to Day 150

RSV-associated hospitalization is defined as a hospital admission for respiratory illness and RSV-positive RT-PCR nasopharyngeal sample. Per protocol, the number of participants with RSV-associated hospitalization were reported for RSV season 1.

RSV Season 1: Number of Participants With RSV-Associated MALRIFrom Day 1 (postdose) to Day 180

Outpatient and inpatient MALRI was defined as the presence of the following in a clinical setting: 1) cough or difficulty breathing; AND 2) 1 or more of wheezing, chest wall in-drawing/retraction, rales/crackles, hypoxemia, tachypnea, or dehydration due to respiratory symptoms; AND 3) RSV-positive RT-PCR nasopharyngeal sample. Per protocol, participants with outpatient and inpatient RSV-associated MALRI were reported together for RSV season 1 participants.

Trial Locations

Locations (217)

Southeastern Pediatric Associates, P.A. ( Site 0008)

🇺🇸

Dothan, Alabama, United States

Northwest Arkansas Pediatric Clinic ( Site 0050)

🇺🇸

Fayetteville, Arkansas, United States

Children's Clinic of Jonesboro, PA ( Site 0058)

🇺🇸

Jonesboro, Arkansas, United States

Long Beach Memorial Medical Center ( Site 0014)

🇺🇸

Long Beach, California, United States

Madera Family Medical Group ( Site 0046)

🇺🇸

Madera, California, United States

Orange County Research Institute ( Site 0057)

🇺🇸

Ontario, California, United States

Children's Hospital Colorado ( Site 0066)

🇺🇸

Aurora, Colorado, United States

Optumcare Colorado Springs, LLC ( Site 0022)

🇺🇸

Colorado Springs, Colorado, United States

Children's National Hospital ( Site 0076)

🇺🇸

Washington, District of Columbia, United States

MedStar Georgetown Pediatrics ( Site 0047)

🇺🇸

Washington, District of Columbia, United States

Scroll for more (207 remaining)
Southeastern Pediatric Associates, P.A. ( Site 0008)
🇺🇸Dothan, Alabama, United States

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