Arginase 1 DeficiencyPhase 3NCT06582524
Pegzilarginase in Subjects <24 Months Old With Arginase 1 Deficiency
A Phase 3 study testing Pegzilarginase in people with Arginase 1 Deficiency, run by Immedica Pharma AB at 3 sites in 3 countries.
Trial summary
This is an open-label, multicentre study to evaluate the safety, PK, and activity (PD) of weekly subcutaneous (SC) administration of pegzilarginase in subjects with ARG1-D who are < 24 months of age. Read more about this study
- Who is it for?
- Ages 1 day to 24 months
- Conditions the study is for
- Arginase 1 Deficiency
- What is being tested?
- Pegzilarginase
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 3 participants
- Where
- 3 sitesin 3 countries
- Study dates
- 30 Aug 2024to 17 Jun 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 1 day to 24 months
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Subjects must be < 24 months of age on the date of informed consent
- Confirmed diagnosis of ARG1-D documented in medical records by at least 1 of the following methods:
- elevated plasma arginine levels
- a mutation analysis revealing a pathogenic variant
- red blood cell (RBC) arginase activity
- Subjects must weigh > 8 kg due to clinical trial related blood collection volumes required
Show all 11Show fewer
- Written informed consent by parent/legal guardian, in accordance with national stipulations, which includes compliance with the requirements and restrictions listed in the informed consent form and in this protocol
- At least one value of plasma arginine ≥ 180 μM during screening
- Documented confirmation from the Investigator and/or dietitian that the subject can:
- attempt to maintain a stable, age-appropriate level of protein consumption, including natural protein, and EAA supplementation within approximately ± 15% of dietitian recommended diet
- attempt to maintain current use of ammonia scavengers, if prescribed
Who cannot join
- Other medical condition(s) or comorbidity(ies) that, in the opinion of the Investigator, would interfere with study compliance or data interpretation
- Hyperammonaemic episode (plasma ammonia levels > 100 μM) with ≥ 1 symptom related to hyperammonaemia requiring hospitalisation or emergency room management within the 4 weeks before the first dose of study drug
- Active infection requiring anti-infective therapy within < 2 weeks before first dose of study drug
- Known active infection with human immunodeficiency virus, hepatitis B, or hepatitis C
- History of hypersensitivity to polyethylene glycol (PEG) or any of the excipients included in the study drug that, in the judgment of the Investigator, puts the subject at unacceptable risk for AEs
- Currently participating in another therapeutic clinical study or has received any investigational agent within 30 days (or 5 half-lives, whichever is longer) prior to first dose of study drug
- Previous liver or haematopoietic stem cell transplant
- Use of botulinum toxin within 16 weeks prior to first dose
Trial locations and contacts
3 sites in 3 countries.
3 sites in 3 countries
Austria1 site
Univ. Klinik für Kinder- und Jugendheilkunde Medizinische Universität
Graz, A-8036
Portugal1 site
Unidade de Doenças Metabólicas Pediatria, Hospital Santa Maria
Lisbon
United Kingdom1 site
Bradford Royal Infirmary Duckworth Lane
Bradford, BD9 6RJ
About this study
Official title: A Phase 3 Open-Label Study of Safety, Pharmacokinetics, and Activity of Weekly Subcutaneous Pegzilarginase in Subjects <24 Months Old With Arginase 1 Deficiency
This is an open-label, multicentre study to evaluate the safety, PK, and activity (PD) of weekly subcutaneous (SC) administration of pegzilarginase in subjects with ARG1-D who are < 24 months of age. The study consists of a screening period of up to 4 weeks, a subsequent 12-week treatment period, and a safety follow-up period of 8 weeks.
Read the detailed description
CAEB1102-301A is an open-label, single-arm, non-controlled, repeat dosing, multicentre study to evaluate the safety, PK, and activity (PD) of weekly SC administration of pegzilarginase over 12 weeks in subjects with ARG1-D who are < 24 months of age.
This study will consist of:
- A screening period of up to 4 weeks to ensure the subjects meet the study eligibility criteria and establish baseline plasma arginine
- A treatment period of 12 weeks
- A safety follow-up period of 8 weeks with visits 1 week and 8 weeks after the last dose.
- Conditions
- Arginase 1 Deficiency
- Being tested
- Pegzilarginase
- Medical subject headings
- Hyperargininemia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PegzilarginaseDrug
Also called Loargys
SC administration of pegzilarginase over 12 weeks in subjects with ARG1-D who are < 24 months of age
| Study group | Role | What they receive |
|---|---|---|
| Weekly subcutaneous (SC) administration of pegzilarginase | Experimental | All subjects will receive a once weekly (QW) SC dose of pegzilarginase for 12 weeks Receives: Drug: Pegzilarginase |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change From Baseline in Plasma Arginine Concentrations in Subjects <24 Months of Age With Arginase 1 Deficiency (ARG1-D).
To evaluate the effect of pegzilarginase on plasma arginine concentrations in subjects <24 months of age with arginase 1 deficiency (ARG1-D).
Measured: From baseline up to 12 weeks.
Secondary outcomes (7)
Pharmacokinetic (PK) Profile of Pegzilarginase: Half-life (T½).
PK parameters with evaluation of half-life (T½).
Measured: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Maximum Observed Concentration (Tmax).
PK parameters with evaluation on time to maximum observed concentration (Tmax).
Measured: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Maximum Observed Concentration (Cmax).
PK parameters with evaluation of maximum observed concentration (Cmax).
Measured: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Area Under the Plasma Drug Concentration-time Curve.
PK parameters with evaluation on area under the plasma drug concentration-time curve.
Measured: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacodynamic (PD) Response of Pegzilarginase: Anti-drug Antibodies (ADAs).
PD response evaluation, anti-drug antibodies (ADAs).
Measured: From baseline up to 12 weeks. Samples taken on visit 1, 2, 4, 8 and 13 (pre-dose if on a dosing day).
Pharmacodynamic (PD) Response of Pegzilarginase: Levels of Plasma Arginine.
PD response evaluation, levels of plasma arginine. Arginine within guidance level.
Measured: From baseline up to 12 weeks. Samples taken on visit 1, 2, 4, 8 and 13 (pre-dose if on a dosing day).
Changes From Baseline in Physical Function: GMFM-66.
Changes in physical function after 12 weeks of pegzilarginase treatment as measured by Gross Motor Function Measure (GMFM)-66 Parts A through E (total score). The Gross Motor Function Measure (GMFM) utilize a 4-point scoring system for each item across dimensions A-E. The minimum score is 0; the maximum score is 198, with a higher score representing better gross motor function.
Measured: From baseline up to 12 weeks.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Sep 2024
- Study start30 Aug 2024
- Primary completion17 Jun 2025
- Study completion17 Jun 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 Arginase 1 DeficiencyStudies of the same condition, open and under way.
- 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
- 3 participants (actual)
Sponsor and investigators
- Lead sponsor
- Immedica Pharma AB
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Mattias Rudebeck, PhD MSc BMedSc, Study director, Immedica Pharma AB
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06582524
- Sponsor's protocol ID
- CAEB1102-301A (Europe)
- Status last verified
- Nov 2025
- First submitted
- 20 Aug 2024
- Last updated
- 22 May 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 22 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3 Open-Label Study of Safety, Pharmacokinetics, and Activity of Weekly Subcutaneous Pegzilarginase in Subjects <24 Months Old With Arginase 1 Deficiency
- ClinicalTrials.gov ID
- NCT06582524
- Acronym / sponsor ID
- CAEB1102-301A (Europe)
- Conditions
- Arginase 1 Deficiency
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 3 participants (actual)
- Lead sponsor
- Immedica Pharma ABIndustry (pharma, biotech, devices)
- Study start
- 30 Aug 2024 (actual)
- Primary completion
- 17 Jun 2025 (actual)
- Study completion
- 17 Jun 2025 (actual)
- First posted
- 3 Sep 2024 (actual)
- Results
- Posted 30 Apr 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is an open-label, multicentre study to evaluate the safety, PK, and activity (PD) of weekly subcutaneous (SC) administration of pegzilarginase in subjects with ARG1-D who are < 24 months of age. The study consists of a screening period of up to 4 weeks, a subsequent 12-week treatment period, and a safety follow-up period of 8 weeks.
Detailed description
CAEB1102-301A is an open-label, single-arm, non-controlled, repeat dosing, multicentre study to evaluate the safety, PK, and activity (PD) of weekly SC administration of pegzilarginase over 12 weeks in subjects with ARG1-D who are < 24 months of age.
This study will consist of:
- A screening period of up to 4 weeks to ensure the subjects meet the study eligibility criteria and establish baseline plasma arginine
- A treatment period of 12 weeks
- A safety follow-up period of 8 weeks with visits 1 week and 8 weeks after the last dose.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Weekly subcutaneous (SC) administration of pegzilarginase | Experimental | Drug: PegzilarginaseAll subjects will receive a once weekly (QW) SC dose of pegzilarginase for 12 weeks |
Who may qualify
- Ages
- 1 day to 24 months
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (11 listed)
- Subjects must be < 24 months of age on the date of informed consent
- Confirmed diagnosis of ARG1-D documented in medical records by at least 1 of the following methods:
- Subjects must weigh > 8 kg due to clinical trial related blood collection volumes required
- Written informed consent by parent/legal guardian, in accordance with national stipulations, which includes compliance with the requirements and restrictions listed in the informed consent form and in this protocol
- At least one value of plasma arginine ≥ 180 μM during screening
Key exclusion criteria (8 listed)
- Other medical condition(s) or comorbidity(ies) that, in the opinion of the Investigator, would interfere with study compliance or data interpretation
- Hyperammonaemic episode (plasma ammonia levels > 100 μM) with ≥ 1 symptom related to hyperammonaemia requiring hospitalisation or emergency room management within the 4 weeks before the first dose of study drug
- Active infection requiring anti-infective therapy within < 2 weeks before first dose of study drug
- Known active infection with human immunodeficiency virus, hepatitis B, or hepatitis C
- History of hypersensitivity to polyethylene glycol (PEG) or any of the excipients included in the study drug that, in the judgment of the Investigator, puts the subject at unacceptable risk for AEs
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 |
|---|---|---|
| PegzilarginaseAlso: LoargysSC administration of pegzilarginase over 12 weeks in subjects with ARG1-D who are < 24 months of age | Drug | Weekly subcutaneous (SC) administration of pegzilarginase |
Primary outcome
Change From Baseline in Plasma Arginine Concentrations in Subjects <24 Months of Age With Arginase 1 Deficiency (ARG1-D).
Time frame: From baseline up to 12 weeks.
To evaluate the effect of pegzilarginase on plasma arginine concentrations in subjects <24 months of age with arginase 1 deficiency (ARG1-D).
7 secondary outcomes
Pharmacokinetic (PK) Profile of Pegzilarginase: Half-life (T½).
Time frame: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Maximum Observed Concentration (Tmax).
Time frame: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Maximum Observed Concentration (Cmax).
Time frame: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacokinetic (PK) Profile of Pegzilarginase: Area Under the Plasma Drug Concentration-time Curve.
Time frame: From baseline up to 12 weeks. Within 1 hour pre-dose a sample was taken on visits 1, 2, 4, 6, 8, 10, and 13. A post-dose sample was taken 12 - 48 hours after dosing on visits 2, 4, and 10.
Pharmacodynamic (PD) Response of Pegzilarginase: Anti-drug Antibodies (ADAs).
Time frame: From baseline up to 12 weeks. Samples taken on visit 1, 2, 4, 8 and 13 (pre-dose if on a dosing day).
Pharmacodynamic (PD) Response of Pegzilarginase: Levels of Plasma Arginine.
Time frame: From baseline up to 12 weeks. Samples taken on visit 1, 2, 4, 8 and 13 (pre-dose if on a dosing day).
Changes From Baseline in Physical Function: GMFM-66.
Time frame: From baseline up to 12 weeks.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 May 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Individual participant dataSharing planned: No
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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.
Mattias Rudebeck, PhD MSc BMedSc study director
Immedica Pharma AB
3 sites in 3 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Pegzilarginase in people with Arginase 1 Deficiency, run by Immedica Pharma AB at 3 sites in 3 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 11 inclusion and 8 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 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in Austria, Portugal, United Kingdom. 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 30 Apr 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?
Change From Baseline in Plasma Arginine Concentrations in Subjects <24 Months of Age With Arginase 1 Deficiency (ARG1-D). (time frame: From baseline up to 12 weeks.). 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 22 May 2026.