Hereditary Angioedema (HAE)Phase 3NCT05819775
CSL312_3003 Safety and Pharmacokinetic Study in Subjects 2 to 11 Years of Age With Hereditary Angioedema
A Phase 3 study testing CSL312 in people with Hereditary Angioedema (HAE), run by CSL Behring at 13 sites in 5 countries.
Trial summary
The purpose of this study is to investigate the safety, PK / PD, and efficacy of SC CSL312 for prophylactic treatment of pediatric subjects with HAE. Read more about this study
- Who is it for?
- Ages 2 to 11 years
- Conditions the study is for
- Hereditary Angioedema (HAE)
- What is being tested?
- CSL312
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 22 participants
- Where
- 13 sitesin 5 countries
- Study dates
- 30 May 2023to 19 Nov 2025
- Phase
- Phase 3
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 2 to 11 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Male or female
- Aged 2 to 11 years, inclusive, with body weight ≥ 10th percentile based on age
- Diagnosed with clinically confirmed C1-INH HAE
- Experienced ≥ 2 HAE attacks during the 6 months before Screening
Who cannot join
- Concomitant diagnosis of another form of angioedema, such as idiopathic or acquired angioedema, recurrent angioedema associated with urticaria, or HAE type 3
- Use of C1-INH products, androgens, antifibrinolytics, approved or future approved medications, or other small molecule medications for routine prophylaxis against HAE attacks within a minimum of 2 weeks before the Treatment Period
- Participation in another interventional clinical study during the 30 days before the Treatment Period or within 5 half-lives of the final dose of the investigational product administered during the previous interventional study, whichever is longer
- Having laboratory clinical abnormalities assessed as clinically significant by the investigator in results of hematology or chemistry assessments performed during Screening
- Currently receiving a therapy not permitted during the study
- Being pregnant or breastfeeding.
Trial locations and contacts
13 sites in 5 countries.
13 sites in 5 countries
United States7 sites
Bernstein Clinical Research
Cincinnati, Ohio, 45236
AARA Research Center
Dallas, Texas, 75231
PennState Health Milton S. Hershey Medical Center
Hershey, Pennsylvania, 17033
Research Solutions of Arizona
Litchfield Park, Arizona, 85340
Donald S. Levy M.D.
Orange, California, 92868
Raffi Tachdjian MD, Inc.
Santa Monica, California, 90404
Medical Research of Arizona
Scottsdale, Arizona, 85251
Germany3 sites
Charité - Universitätsmedizin Berlin
Berlin, 12203
HZRM Hämophilie Zentrum Rhein Main GmbH
Frankfurt am Main, Hesse, 60596
Universitätsklinikum Frankfurt
Frankfurt am Main, 60590
Australia1 site
Campbelltown Hospital, Western Sydney University
Campbelltown, NSW 2560
About this study
Official title: A Phase 3 Open-label Study to Evaluate the Safety, Pharmacokinetics, Pharmacodynamics, and Efficacy of CSL312 (Garadacimab) in the Prophylactic Treatment of Hereditary Angioedema in Pediatric Subjects 2 to 11 Years of Age
The purpose of this study is to investigate the safety, PK / PD, and efficacy of SC CSL312 for prophylactic treatment of pediatric subjects with HAE.
- Conditions
- Hereditary Angioedema (HAE)
- Being tested
- CSL312
- Medical subject headings
- Angioedemas, Hereditary
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CSL312Biological
Also called Garadacimab
Fully human immunoglobulin G subclass 4/lambda recombinant inhibitor monoclonal antibody administered subcutaneously (SC)
| Study group | Role | What they receive |
|---|---|---|
| CSL312 | Experimental | Ages 2-5 years and 6-11 years will have specific subcutaneous dosing schedules Receives: Biological: CSL312 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With Treatment Emergent Adverse Events (TEAE)
Measured: Up to Month 12
Percentage of Participants With TEAE
The percentage of participants was rounded to one place of decimal.
Measured: Up to Month 12
Number of TEAE
Measured: Up to Month 12
TEAE Rates Per Injection
The TEAE rate per injection was calculated as the number of TEAE/ number of injections. The number of injections was defined as the total injections a participant received during the Safety Evaluation Period under the dosing regimen to which the TEAE was assigned.
Measured: Up to Month 12
TEAE Rates Per Participant-Year
The TEAE rate per participant year was calculated as number of TEAEs/ participant years. Participant-years of exposure were calculated as the sum of each participant's exposure duration (in years) under the specified dosing regimen or overall. For the time assigned to a dosing regimen, each study day was counted under the corresponding regimen.
Measured: Up to Month 12
Maximum Concentration (Cmax) of CSL312 at Steady-state
Measured: Up to Month 12
Trough Concentration (Ctrough) of CSL312 at Steady-state
Measured: At Months 3, 4, 6, 9, 10, and 12
Time to Maximum Concentration (Tmax) of CSL312 at Steady-State
Measured: Up to Month 12
Secondary outcomes (20)
Time-normalized Number of HAE Attacks Per Month
Time-normalized number of HAE attacks per month during treatment was calculated per participant as: [Number of HAE attacks / Length of participant treatment in days] * 30.4375.
Measured: Up to Month 12
Time-normalized Number of HAE Attacks Per Year
Time-normalized number of HAE attacks per year during treatment was calculated per participant as: [Number of HAE attacks / Length of participant treatment in days] * 365.25.
Measured: Up to Month 12
Time-normalized Number of HAE Attacks Treated With On-demand Treatment Per Month
The time-normalized number of HAE attacks per month treated with on-demand treatment were calculated as follows:
[(Number of HAE attacks treated with on - demand treatment during treatment period)/ Length of participant treatment in days] ∗ 30.4375.
Measured: Up to Month 12
Time-normalized Number of HAE Attacks Treated With On-demand Treatment Per Year
The time-normalized number of HAE attacks per year treated with on-demand treatment were calculated as follows:
[(Number of HAE attacks treated with on - demand treatment during treatment period)/ Length of participant treatment in days] ∗ 365.25.
Measured: Up to Month 12
Time-normalized Number of Moderate and/or Severe HAE Attacks Per Month
Time-normalized number of moderate or severe HAE attacks per month during treatment period was calculated per participant as: [number of moderate or severe HAE attacks / length of participant treatment in days] * 30.4375.
Measured: Up to Month 12
Time-normalized Number of Moderate and/or Severe HAE Attacks Per Year
Time-normalized number of moderate or severe HAE attacks per month during treatment period was calculated per participant as: [number of moderate or severe HAE attacks / length of participant treatment in days] * 365.25.
Measured: Up to Month 12
Percentage Reduction in the Time-normalized Number of HAE Attacks
The percentage reduction in the time-normalized number of HAE attacks was calculated within a participant as follows: 100*[ 1 - (Time-normalized number of HAE attacks per month during treatment period/Time-normalized number of HAE attacks per month from historical data)].
Measured: Up to Month 12
Number of Participants Experiencing at Least Greater Than or Equal to (>=) 50 Percent (%), >= 70%, >= 90%, or Equal to 100% (Attack-free) Reduction in the Time-normalized Number of HAE Attacks
A participant was classified as a responder if the percentage reduction in the time-normalized number of HAE attacks under treatment compared to the time-normalized number of HAE attacks documented in the medical records was >= 50%. Percent Reduction = 100 * [1 - (time-normalized number of HAE attacks during corresponding time window / time-normalized number of HAE attacks based on historical data)]. Here number of participants experiencing at least >= 50%, >= 70%, >= 90%, or equal to 100% (Attack-free) reduction in the time-normalized number of HAE attacks are reported. The number of responders at each reduction category have been reported.
Measured: Up to Month 12
Number of Participants Experiencing Serious Adverse Events (SAE), Experiencing Death, Related TEAE, TEAE Leading to Study Discontinuation
Measured: Up to Month 12
Percentage of Participants Experiencing SAE, Experiencing Death, Related TEAE, TEAE Leading to Study Discontinuation
The percentage of participants was rounded to one decimal place.
Measured: Up to Month 12
Number of Participants With TEAE by Severity
Severity of AE was assessed by the investigator and categorized as mild, moderate and severe where:
Mild: AE that is usually transient and may require only minimal treatment or therapeutic intervention. The event does not generally interfere with usual activities of daily living. Moderate: AE that is usually alleviated with additional specific therapeutic intervention. The event interferes with usual activities of daily living, causing discomfort but poses no significant or permanent risk of harm to the research participant. Severe: AE that interrupts usual activities of daily living, significantly affects clinical status, or may require intensive therapeutic intervention.
Measured: Up to Month 12
Percentage of Participants With TEAE by Severity
Severity of AE was assessed by the investigator and categorized as mild, moderate and severe where:
Mild: AE that is usually transient and may require only minimal treatment or therapeutic intervention. The event does not generally interfere with usual activities of daily living. Moderate: AE that is usually alleviated with additional specific therapeutic intervention. The event interferes with usual activities of daily living, causing discomfort but poses no significant or permanent risk of harm to the research participant. Severe: AE that interrupts usual activities of daily living, significantly affects clinical status, or may require intensive therapeutic intervention. The percentage of participants was rounded to one place of decimal.
Measured: Up to Month 12
Number of Participants With Anti-CSL312 Antibodies
Measured: At Day 1, Months 6 and 12
Percentage of Participants With Anti-CSL312 Antibodies
The percentage of participants was rounded to one place of decimal.
Measured: At Day 1, Months 6 and 12
Number of Participants With Adverse Events of Special Interest (AESI)
AESI included severe hypersensitivity including anaphylaxis. The AESI reported have been identified by investigators and suggestive events were independently identified for further review with a Standardized MedDRA Query (SMQ).
Measured: Up to Month 12
Percentage of Participants With AESI
AESI included severe hypersensitivity including anaphylaxis. The AESI reported have been identified by investigators and suggestive events were independently identified for further review with an SMQ. The percentage of participants was rounded to one place of decimal.
Measured: Up to Month 12
FXIIa-mediated Kallikrein Activity
Measured: At Months 3, 4, and 12 and pre-dose and post dose at Months 6, 9, and 10
Percent of Baseline FXIIa-mediated Kallikrein Activity
Percent of Baseline at Visit [i] = 100 * (actual value at Visit [i] / Baseline value), where Baseline is defined as the most recent, non-missing value before the first IP administration (including unscheduled visits). Here unit of measure is Percent (%) of FXIIa-mediated Kallikrein Activity.
Measured: At Months 3, 4, and 12 and pre-dose and post dose at Months 6, 9, and 10
Number of Participants With Laboratory Findings Reported as AE
Measured: Up to Month 12
Percentage of Participants With Laboratory Findings Reported as AE
The participant data were rounded to one decimal place.
Measured: Up to Month 12
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Apr 2023
- Study start30 May 2023
- Primary completion19 Nov 2025
- Study completion19 Nov 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Hereditary Angioedema (HAE)Studies of the same condition, open and under way.
- More trials run by CSL BehringThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 22 participants (actual)
Sponsor and investigators
- Lead sponsor
- CSL Behring
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Study Director, Study director, CSL Behring
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05819775
- Sponsor's protocol ID
- CSL312_3003
- Other IDs
- 2022-502386-13-00
- Status last verified
- Apr 2026
- First submitted
- 4 Apr 2023
- Last updated
- 2 Jun 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: CSL will consider on a case-by-case basis requests to share Individual Patient Data (IPD) with external bona-fide, qualified scientific and medical researchers. For information on the process and requirements for submitting a voluntary data sharing request for IPD, please contact CSL at clinicaltrials@cslbehring.com.
Study at a glance
From the registry record, last updated by the sponsor on 2 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3 Open-label Study to Evaluate the Safety, Pharmacokinetics, Pharmacodynamics, and Efficacy of CSL312 (Garadacimab) in the Prophylactic Treatment of Hereditary Angioedema in Pediatric Subjects 2 to 11 Years of Age
- ClinicalTrials.gov ID
- NCT05819775
- Acronym / sponsor ID
- CSL312_3003
- Conditions
- Hereditary Angioedema (HAE)
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 22 participants (actual)
- Lead sponsor
- CSL BehringIndustry (pharma, biotech, devices)
- Study start
- 30 May 2023 (actual)
- Primary completion
- 19 Nov 2025 (actual)
- Study completion
- 19 Nov 2025 (actual)
- First posted
- 19 Apr 2023 (actual)
- Results
- Posted 2 Jun 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to investigate the safety, PK / PD, and efficacy of SC CSL312 for prophylactic treatment of pediatric subjects with HAE.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| CSL312 | Experimental | Biological: CSL312Ages 2-5 years and 6-11 years will have specific subcutaneous dosing schedules |
Who may qualify
- Ages
- 2 to 11 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (4 listed)
- Male or female
- Aged 2 to 11 years, inclusive, with body weight ≥ 10th percentile based on age
- Diagnosed with clinically confirmed C1-INH HAE
- Experienced ≥ 2 HAE attacks during the 6 months before Screening
Key exclusion criteria (6 listed)
- Concomitant diagnosis of another form of angioedema, such as idiopathic or acquired angioedema, recurrent angioedema associated with urticaria, or HAE type 3
- Use of C1-INH products, androgens, antifibrinolytics, approved or future approved medications, or other small molecule medications for routine prophylaxis against HAE attacks within a minimum of 2 weeks before the Treatment Period
- Participation in another interventional clinical study during the 30 days before the Treatment Period or within 5 half-lives of the final dose of the investigational product administered during the previous interventional study, whichever is longer
- Having laboratory clinical abnormalities assessed as clinically significant by the investigator in results of hematology or chemistry assessments performed during Screening
- Currently receiving a therapy not permitted during the study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CSL312Also: GaradacimabFully human immunoglobulin G subclass 4/lambda recombinant inhibitor monoclonal antibody administered subcutaneously (SC) | Biological | CSL312 |
Primary outcome
Number of Participants With Treatment Emergent Adverse Events (TEAE)
Time frame: Up to Month 12
Percentage of Participants With TEAE
Time frame: Up to Month 12
The percentage of participants was rounded to one place of decimal.
Number of TEAE
Time frame: Up to Month 12
TEAE Rates Per Injection
Time frame: Up to Month 12
The TEAE rate per injection was calculated as the number of TEAE/ number of injections. The number of injections was defined as the total injections a participant received during the Safety Evaluation Period under the dosing regimen to which the TEAE was assigned.
TEAE Rates Per Participant-Year
Time frame: Up to Month 12
The TEAE rate per participant year was calculated as number of TEAEs/ participant years. Participant-years of exposure were calculated as the sum of each participant's exposure duration (in years) under the specified dosing regimen or overall. For the time assigned to a dosing regimen, each study day was counted under the corresponding regimen.
Maximum Concentration (Cmax) of CSL312 at Steady-state
Time frame: Up to Month 12
Trough Concentration (Ctrough) of CSL312 at Steady-state
Time frame: At Months 3, 4, 6, 9, 10, and 12
Time to Maximum Concentration (Tmax) of CSL312 at Steady-State
Time frame: Up to Month 12
20 secondary outcomes
Time-normalized Number of HAE Attacks Per Month
Time frame: Up to Month 12
Time-normalized Number of HAE Attacks Per Year
Time frame: Up to Month 12
Time-normalized Number of HAE Attacks Treated With On-demand Treatment Per Month
Time frame: Up to Month 12
Time-normalized Number of HAE Attacks Treated With On-demand Treatment Per Year
Time frame: Up to Month 12
Time-normalized Number of Moderate and/or Severe HAE Attacks Per Month
Time frame: Up to Month 12
Time-normalized Number of Moderate and/or Severe HAE Attacks Per Year
Time frame: Up to Month 12
Percentage Reduction in the Time-normalized Number of HAE Attacks
Time frame: Up to Month 12
Number of Participants Experiencing at Least Greater Than or Equal to (>=) 50 Percent (%), >= 70%, >= 90%, or Equal to 100% (Attack-free) Reduction in the Time-normalized Number of HAE Attacks
Time frame: Up to Month 12
Number of Participants Experiencing Serious Adverse Events (SAE), Experiencing Death, Related TEAE, TEAE Leading to Study Discontinuation
Time frame: Up to Month 12
Percentage of Participants Experiencing SAE, Experiencing Death, Related TEAE, TEAE Leading to Study Discontinuation
Time frame: Up to Month 12
Number of Participants With TEAE by Severity
Time frame: Up to Month 12
Percentage of Participants With TEAE by Severity
Time frame: Up to Month 12
Number of Participants With Anti-CSL312 Antibodies
Time frame: At Day 1, Months 6 and 12
Percentage of Participants With Anti-CSL312 Antibodies
Time frame: At Day 1, Months 6 and 12
Number of Participants With Adverse Events of Special Interest (AESI)
Time frame: Up to Month 12
Percentage of Participants With AESI
Time frame: Up to Month 12
FXIIa-mediated Kallikrein Activity
Time frame: At Months 3, 4, and 12 and pre-dose and post dose at Months 6, 9, and 10
Percent of Baseline FXIIa-mediated Kallikrein Activity
Time frame: At Months 3, 4, and 12 and pre-dose and post dose at Months 6, 9, and 10
Number of Participants With Laboratory Findings Reported as AE
Time frame: Up to Month 12
Percentage of Participants With Laboratory Findings Reported as AE
Time frame: Up to Month 12
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Jun 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: Yes. CSL will consider on a case-by-case basis requests to share Individual Patient Data (IPD) with external bona-fide, qualified scientific and medical researchers. For information on the process and requirements for submitting a voluntary data sharing request for IPD, please contact CSL at clinicaltrials@cslbehring.com.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Study Director study director
CSL Behring
13 sites in 5 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing CSL312 in people with Hereditary Angioedema (HAE), run by CSL Behring at 13 sites in 5 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 13 sites in United States, Germany, Australia, Canada, Israel. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 2 Jun 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of Participants With Treatment Emergent Adverse Events (TEAE) (time frame: Up to Month 12). The study lists 8 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Jun 2026.