Trial · NCT04767373
Efficacy and Safety of Clesrovimab (MK-1654) in Infants (MK-1654-004)
NCT04767373, Phase 2, Phase 3, Completed, Merck Sharp & Dohme LLC; results first posted 2025-02-04
3 sourcestrials-2026-11-12-0.5.0
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ConductScience Library. Efficacy and Safety of Clesrovimab (MK-1654) in Infants (MK-1654-004). Trials, record NCT04767373. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04767373
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Trial
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
- Title
- Efficacy and Safety of Clesrovimab (MK-1654) in Infants (MK-1654-004)
- NCT number
- NCT04767373
- Status
- Completed
- Phases
- Phase 2, Phase 3
- Enrollment
- 3,632 participants, actual
- Lead sponsor
- Merck Sharp & Dohme LLC
- Conditions
- Respiratory Syncytial Virus Infection
- Interventions
- Clesrovimab, Placebo
- First posted
- 2021-02-23
- Last updated
- 2026-02-11
- Other registries' IDs
- eudract:2020-002405-26
- Results first posted
- 2025-02-04
Source ClinicalTrials.gov
Registered outcomes10
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description |
|---|---|---|---|
| Primary | 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. |
| Primary | 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. |
| Primary | RSV Season 1: Percentage of Participants With Fever | From 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. |
| Primary | RSV Season 1: Percentage of Participants With Solicited Systemic 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 systemic AEs included irritability, somnolence/drowsiness, and appetite lost. Per protocol, the percentage of RSV season 1 participants with solicited systemic AEs were reported. |
| Primary | 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. |
| Primary | RSV Season 1: Percentage of Participants With Rash 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. 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. |
| Primary | RSV Season 1: Percentage of Participants With ≥1 Nonserious AE | 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. Per protocol, the percentage of RSV season 1 participants with ≥1 nonserious AE were reported. |
| Primary | 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 | RSV Season 1: Number of Participants With RSV-Associated Hospitalization | From 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. |
| Secondary | RSV Season 1: Number of Participants With RSV-Associated MALRI | From 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. |
Source ClinicalTrials.gov
Outcomes10
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as |
|---|---|---|---|---|---|
| PRIMARY | 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 | All randomized participants who received a dose of study treatment and were protocol compliant. | Participants | COUNT_OF_PARTICIPANTS |
| PRIMARY | RSV Season 1: Percentage of Participants With Solicited Injection-Site Adverse Events (AEs) | From Day 1 (postdose) to Day 5 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | RSV Season 1: Percentage of Participants With Fever | From Day 1 (postdose) to Day 5 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment and had temperature data available. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | RSV Season 1: Percentage of Participants With Solicited Systemic AEs | From Day 1 (postdose) to Day 5 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | RSV Season 1: Percentage of Participants With Anaphylaxis/Hypersensitivity AE of Special Interest (AESI) | From Day 1 (postdose) to Day 42 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | RSV Season 1: Percentage of Participants With Rash AESI | From Day 1 (postdose) to Day 42 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | RSV Season 1: Percentage of Participants With ≥1 Nonserious AE | From Day 1 (postdose) to Day 42 | Safety analysis population included all randomized participants who received a dose of protocol specified study treatment. Per protocol, in the safety analysis population, participants with protocol deviation were excluded. | Percentage of participants | NUMBER |
| PRIMARY | Percentage of Participants With Serious Adverse Events (SAEs) | RSV Season 1: Day 1 to Day 365, RSV Season 2: Day 366 to Day 515 | Safety analysis population which included all randomized participants who received a dose of protocol specified study treatment. For safety analysis population, participants with protocol deviation were excluded. Per protocol, a subset of participants from RSV season 1 entered RSV season 2 and SAEs were collected separately for RSV season 1 and RSV Season 2. | Percentage of participants | NUMBER |
| SECONDARY | RSV Season 1: Number of Participants With RSV-Associated Hospitalization | From Day 1 (postdose) to Day 150 | All randomized participants who received a dose of study treatment and were protocol compliant. | Participants | COUNT_OF_PARTICIPANTS |
| SECONDARY | RSV Season 1: Number of Participants With RSV-Associated MALRI | From Day 1 (postdose) to Day 180 | All randomized participants who received a dose of study treatment and were protocol compliant. | Participants | COUNT_OF_PARTICIPANTS |
Source ClinicalTrials.gov
Results by group22
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units |
|---|---|---|---|---|---|
| RSV Season 1: Number of Participants With Respiratory Syncytial Virus (RSV)-Associated Medically Attended Lower Respiratory Infection (MALRI) | RSV Season 1: Clesrovimab 105 mg | 60 | Participants | ||
| RSV Season 1: Number of Participants With Respiratory Syncytial Virus (RSV)-Associated Medically Attended Lower Respiratory Infection (MALRI) | RSV Season 1: Placebo | 74 | Participants | ||
| RSV Season 1: Percentage of Participants With Solicited Injection-Site Adverse Events (AEs) | RSV Season 1: Clesrovimab 105 mg | 11.4 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Solicited Injection-Site Adverse Events (AEs) | RSV Season 1: Placebo | 11.7 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Fever | RSV Season 1: Clesrovimab 105 mg | 0.5 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Fever | RSV Season 1: Placebo | 1.2 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Solicited Systemic AEs | RSV Season 1: Clesrovimab 105 mg | 30.1 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Solicited Systemic AEs | RSV Season 1: Placebo | 31.2 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Anaphylaxis/Hypersensitivity AE of Special Interest (AESI) | RSV Season 1: Clesrovimab 105 mg | 0.0 | Percentage of participants | ||
| RSV Season 1: Percentage of Participants With Anaphylaxis/Hypersensitivity AE of Special Interest (AESI) | RSV Season 1: Placebo | 0.0 | Percentage of participants |
1 to 10 of 22Source ClinicalTrials.gov
See all 22 results by groupParticipant flow12
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted |
|---|---|---|---|---|
| Overall Study | STARTED | Clesrovimab 105 mg | 2,421 | |
| Overall Study | STARTED | Placebo | 1,211 | |
| Overall Study | Treated | Clesrovimab 105 mg | 2,411 | |
| Overall Study | Treated | Placebo | 1,203 | |
| Overall Study | Safety Analysis Population | Clesrovimab 105 mg | 2,409 | |
| Overall Study | Safety Analysis Population | Placebo | 1,202 | |
| Overall Study | Participants Who Entered RSV Season 2 | Clesrovimab 105 mg | 1,017 | |
| Overall Study | Participants Who Entered RSV Season 2 | Placebo | 501 | |
| Overall Study | COMPLETED | Clesrovimab 105 mg | 2,257 | |
| Overall Study | COMPLETED | Placebo | 1,126 |
1 to 10 of 12Source ClinicalTrials.gov
See all 12 participant flowAdverse events744
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
| Type | Event | Organ system | Group | Affected | At risk | Events |
|---|---|---|---|---|---|---|
| other | Diarrhoea | Gastrointestinal disorders | RSV Season 1: Clesrovimab 105 mg | 139 | 2,409 | 155 |
| other | Diarrhoea | Gastrointestinal disorders | RSV Season 1: Placebo | 77 | 1,202 | 91 |
| other | Diarrhoea | Gastrointestinal disorders | RSV Season 2: Clesrovimab 105 mg | 0 | 0 | 0 |
| other | Diarrhoea | Gastrointestinal disorders | RSV Season 2: Placebo | 0 | 0 | 0 |
| other | Injection site pain | General disorders | RSV Season 1: Clesrovimab 105 mg | 156 | 2,409 | 159 |
| other | Injection site pain | General disorders | RSV Season 1: Placebo | 96 | 1,202 | 97 |
| other | Injection site pain | General disorders | RSV Season 2: Clesrovimab 105 mg | 0 | 0 | 0 |
| other | Injection site pain | General disorders | RSV Season 2: Placebo | 0 | 0 | 0 |
| other | Nasopharyngitis | Infections and infestations | RSV Season 1: Clesrovimab 105 mg | 139 | 2,409 | 158 |
| other | Nasopharyngitis | Infections and infestations | RSV Season 1: Placebo | 78 | 1,202 | 89 |
1 to 10 of 744Source ClinicalTrials.gov
See all 744 adverse eventsAdverse event totals12
The totals the trial posted for each group.
| Total | Group | Affected | At risk |
|---|---|---|---|
| Total, all-cause mortality | RSV Season 1: Clesrovimab 105 mg | 7 | 2,421 |
| Total, all-cause mortality | RSV Season 1: Placebo | 3 | 1,211 |
| Total, all-cause mortality | RSV Season 2: Clesrovimab 105 mg | 0 | 1,017 |
| Total, all-cause mortality | RSV Season 2: Placebo | 0 | 501 |
| Total, other adverse events | RSV Season 1: Clesrovimab 105 mg | 1,432 | 2,409 |
| Total, other adverse events | RSV Season 1: Placebo | 724 | 1,202 |
| Total, other adverse events | RSV Season 2: Clesrovimab 105 mg | 0 | 0 |
| Total, other adverse events | RSV Season 2: Placebo | 0 | 0 |
| Total, serious adverse events | RSV Season 1: Clesrovimab 105 mg | 282 | 2,409 |
| Total, serious adverse events | RSV Season 1: Placebo | 151 | 1,202 |
1 to 10 of 12Source ClinicalTrials.gov
See all 12 adverse event totalsPapers3
The papers the trial lists on ClinicalTrials.gov.
Grants0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
None in this release.
Trial comparisons3
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|---|
| RSV Season 1: Clesrovimab 105 mg vs RSV Season 1: Placebo: RSV Season 1: Number of Participants With RSV-Associated MALRI | Trial comparisons |
| RSV Season 1: Clesrovimab 105 mg vs RSV Season 1: Placebo: RSV Season 1: Number of Participants With Respiratory Syncytial Virus (RSV)-Associated Medically Attended Lower Respiratory Infection (MALRI) | Trial comparisons |
| RSV Season 1: Clesrovimab 105 mg vs RSV Season 1: Placebo: RSV Season 1: Number of Participants With RSV-Associated Hospitalization | Trial comparisons |
Tests0
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
None in this release.
Data dates
The day each source was copied for this release.
Sources 3
- ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
- ClinicalTrials.govNo license stated
- NIH RePORTER's clinical studies and project filesPublic domain
Each source's terms
- ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
- ClinicalTrials.govnone stated
- NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)
ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
For software
Read this trial from software.
The record and each of its lists are JSON, twenty rows a page. No key.
GET https://conductscience.org/api/trials/v1/NCT04767373
GET https://conductscience.org/api/trials/v1/NCT04767373/results?page=2