Trial Outcomes & Findings for COVID-19 Administration of Single-Dose Subcutaneous Anti- Spike(s) SARS-CoV-2 Monoclonal Antibodies Casirivimab and Imdevimab in High-Risk Pediatric Participants Under 12 Years of Age (NCT NCT04992273)
NCT ID: NCT04992273
Last Updated: 2025-10-17
Results Overview
Concentrations reported in milligrams per Liter (mg/L)
Recruitment status
TERMINATED
Study phase
PHASE2
Target enrollment
7 participants
Primary outcome timeframe
Day 0 and Day 14
Results posted on
2025-10-17
Participant Flow
A total of 7 participants were screened. All 7 enrolled into Group A (≥10 kg to \<40 kg). One discontinued at week 9 due to being lost to follow-up. Participants in Group A (≥10 kg to \<40 kg) were subsequently divided into 2 groups for analysis: Group A1 (≥20 kg to \<40 kg) and Group A2 (≥10 kg to \<20 kg) and received different doses. Two participants enrolled in Group A1, 5 enrolled in Group A2; all 7 participants were enrolled and treated.
Participant milestones
| Measure |
≥20 kg to <40 kg
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Overall Study
STARTED
|
2
|
5
|
|
Overall Study
COMPLETED
|
2
|
4
|
|
Overall Study
NOT COMPLETED
|
0
|
1
|
Reasons for withdrawal
| Measure |
≥20 kg to <40 kg
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Overall Study
Lost to Follow-up
|
0
|
1
|
Baseline Characteristics
COVID-19 Administration of Single-Dose Subcutaneous Anti- Spike(s) SARS-CoV-2 Monoclonal Antibodies Casirivimab and Imdevimab in High-Risk Pediatric Participants Under 12 Years of Age
Baseline characteristics by cohort
| Measure |
≥20 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=5 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
Total
n=7 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
9.5 Years
STANDARD_DEVIATION 2.12 • n=5 Participants
|
3.0 Years
STANDARD_DEVIATION 1.58 • n=7 Participants
|
4.9 Years
STANDARD_DEVIATION 3.53 • n=5 Participants
|
|
Sex: Female, Male
Female
|
1 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
5 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
1 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
2 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
1 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
1 Participants
n=5 Participants
|
5 Participants
n=7 Participants
|
6 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
1 Participants
n=5 Participants
|
|
Race (NIH/OMB)
White
|
2 Participants
n=5 Participants
|
4 Participants
n=7 Participants
|
6 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Day 0 and Day 14Population: Here 'n' = the number of evaluable participants at the specified time point
Concentrations reported in milligrams per Liter (mg/L)
Outcome measures
| Measure |
≥10 kg to <40 kg
n=7 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Concentrations of Casirivimab+Imdevimab in Serum Over Time.
Day 0
|
0 mg/L
Standard Deviation 0
|
—
|
|
Concentrations of Casirivimab+Imdevimab in Serum Over Time.
Day 14
|
239.0 mg/L
Standard Deviation 36.3
|
—
|
SECONDARY outcome
Timeframe: Through end of study, approximately 24 weeksPopulation: The Safety Analysis Set (SAF) includes all participants who received any study drug; it is based on the treatment received (as treated).
Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=5 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Treatment-Emergent Adverse Events (TEAEs)
|
2 Participants
|
3 Participants
|
SECONDARY outcome
Timeframe: Through end of study, approximately 24 weeksPopulation: The Safety Analysis Set (SAF) includes all participants who received any study drug; it is based on the treatment received (as treated).
Treatment-emergent adverse events (TEAEs) are defined as those that are not present at baseline or represent the exacerbation of a pre-existing condition during the on-treatment period. The severity of AEs were graded using version 5.0 of NCI-CTCAE.
Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=5 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Indicated Severity of TEAEs
Infections and Infestations - Grade 1
|
1 Participants
|
1 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Infections and Infestations - Grade 2
|
1 Participants
|
1 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Infections and Infestations - Grade 3
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Infections and Infestations - Grade 4
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Infections and Infestations - Grade 5
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Respiratory, thoracic and mediastinal disorders - Grade 1
|
0 Participants
|
1 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Respiratory, thoracic and mediastinal disorders - Grade 2
|
1 Participants
|
1 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Respiratory, thoracic and mediastinal disorders - Grade 3
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Respiratory, thoracic and mediastinal disorders - Grade 4
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Respiratory, thoracic and mediastinal disorders - Grade 5
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Nervous system disorders - Grade 1
|
0 Participants
|
1 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Nervous system disorders - Grade 2
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Nervous system disorders - Grade 3
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Nervous system disorders - Grade 4
|
0 Participants
|
0 Participants
|
|
Number of Participants With Indicated Severity of TEAEs
Nervous system disorders - Grade 5
|
0 Participants
|
0 Participants
|
SECONDARY outcome
Timeframe: Through Day 4Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=5 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Grade ≥3 Injection Site Reactions
|
0 Participants
|
0 Participants
|
SECONDARY outcome
Timeframe: Through Day 4Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=5 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Grade ≥3 Hypersensitivity Reactions
|
0 Participants
|
0 Participants
|
SECONDARY outcome
Timeframe: Up to 24 weeksPopulation: Here 'n' = number of evaluable participants at the specified time point.
Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=4 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Indicated Immunogenicity as Measured by Anti-drug Antibodies (ADA) to Casirivimab Over Time
|
2 Participants
|
3 Participants
|
SECONDARY outcome
Timeframe: Up to 24 weeksPopulation: Here 'n' = number of evaluable participants at the specified time point.
Outcome measures
| Measure |
≥10 kg to <40 kg
n=2 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
≥10 kg to <20 kg
n=4 Participants
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Number of Participants With Indicated Immunogenicity as Measured by ADA to Imdevimab Over Time
|
2 Participants
|
3 Participants
|
SECONDARY outcome
Timeframe: Up to 24 weeksPopulation: Neutralizing antibody (NAb) analysis data was not collected.
Outcome measures
Outcome data not reported
SECONDARY outcome
Timeframe: Up to 24 weeksPopulation: Neutralizing antibody (NAb) analysis data was not collected.
Outcome measures
Outcome data not reported
Adverse Events
Group A1 ≥ 20 kg to <40 kg
Serious events: 0 serious events
Other events: 2 other events
Deaths: 0 deaths
Group A2 ≥ 10 kg to <20 kg
Serious events: 0 serious events
Other events: 3 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Group A1 ≥ 20 kg to <40 kg
n=2 participants at risk
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
Group A2 ≥ 10 kg to <20 kg
n=5 participants at risk
Single dose of casirivimab+imdevimab, that was the body weight dose equivalent to the 1200 mg adult dose (600 mg of casirivimab and 600 mg of imdevimab) administered as 1 to 4 subcutaneous (SC) injections based on body weight.
|
|---|---|---|
|
Infections and infestations
COVID-19
|
50.0%
1/2 • Number of events 1 • From first dose to week 24
|
40.0%
2/5 • Number of events 2 • From first dose to week 24
|
|
Infections and infestations
Gastroenteritis
|
0.00%
0/2 • From first dose to week 24
|
20.0%
1/5 • Number of events 1 • From first dose to week 24
|
|
Infections and infestations
Pneumonia viral
|
50.0%
1/2 • Number of events 1 • From first dose to week 24
|
0.00%
0/5 • From first dose to week 24
|
|
Infections and infestations
Upper respiratory tract infection
|
50.0%
1/2 • Number of events 1 • From first dose to week 24
|
0.00%
0/5 • From first dose to week 24
|
|
Respiratory, thoracic and mediastinal disorders
Cough
|
50.0%
1/2 • Number of events 1 • From first dose to week 24
|
20.0%
1/5 • Number of events 1 • From first dose to week 24
|
|
Respiratory, thoracic and mediastinal disorders
Cough variant asthma
|
0.00%
0/2 • From first dose to week 24
|
20.0%
1/5 • Number of events 1 • From first dose to week 24
|
|
Respiratory, thoracic and mediastinal disorders
Rhinorrhoea
|
50.0%
1/2 • Number of events 1 • From first dose to week 24
|
0.00%
0/5 • From first dose to week 24
|
|
Nervous system disorders
Headache
|
0.00%
0/2 • From first dose to week 24
|
20.0%
1/5 • Number of events 2 • From first dose to week 24
|
Additional Information
Clinical Trials Administrator
Regeneron Pharmaceuticals, Inc.
Phone: 844-734-6643
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee The investigator has the right to independently publish study results from the investigator's site after a multi-center publication, or a defined period after the completion of the study by all sites. The investigator must provide the sponsor a copy of any such publication derived from the study for review and comment in advance of any submission, and delay publication, if requested, to allow the Sponsor to preserve its proprietary rights.
- Publication restrictions are in place
Restriction type: OTHER