Clinical data
Loargys clinical development program: proven efficacy and safety in ARG1-D
A total of 48 patients aged 2–32 years (40 children and 8 adults) with a confirmed diagnosis of ARG1-D have received Loargys in clinical studies. Patients included in the Loargys clinical studies have received treatment for up to approximately 4 years.1-3
The Loargys clinical development program included the first-ever randomised, controlled Phase 3 clinical study in ARG1-D, the Pegzilarginase Effect on Arginase 1 deficiency Clinical Endpoints (PEACE) study.3
Out of 32 patients included in PEACE, 17 were from Europe.
PHASE 3 EFFICACY RESULT
Loargys sustained normal plasma arginine levels for up to 152 weeks3,5
* Treatment guideline plasma arginine; 200 μmol/L. ** Normal range plasma arginine; 40-115 μmol/L, as defined in the PEACE trial.
Loargys sustainably improved functional mobility
- At study completion, the median exposure to Loargys, excluding the 24 weeks of initial exposure, was 94 weeks (range: 62-152 weeks)5
- Sustained and further improved clinically meaningful treatment outcomes demonstrated5
GMFM-E, Gross Motor Function Measure part E; 2MWT, 2-minute walk test; GMFM-D, Gross Motor Function Measure part D; MCID, minimal clinically important difference
Loargys has a manageable safety profile
Hypersensitivity reactions (HSRs)
HSR symptoms includes facial swelling, rash, flushing & dyspnoea1
In clinical studies, when administered IV, 12.5% (6/48) of Loargys-treated patients experienced signs and symptoms either consistent with, or possibly related to an HSR11
Injection site reactions (ISRs)
In clinical studies, ISRs (pain, erythema, swelling, irritation and rash at the injection site) were reported in 13.6% (6/44) of Loargys-treated patients after subcutaneous administration1
Immunogenicity
In clinical studies, 25% (12/48) of Loargys-treated patients tested positive for anti-drug antibodies (ADAs)1
The ADAs were transient in nature and resolved during continued treatment1
- There were no discontinuations due to AEs across all clinical trials. Hypersensitivity reactions and injection site reactions were mild to moderate in severity and resolved spontaneously or with standard medical care1
- HSRs and ISRs were mild to moderate in severity and resolved spontaneously or with standard medical care
Post-marketing
Hypersensitivity reactions were reported, even involving patients treated by subcutaneous administration who were pre-medicated with antihistamines1
Publication
Efficacy and safety of pegzilarginase in arginase 1 deficiency (PEACE): a phase 3, randomized, double-blind, placebo-controlled, multi-centre trial
- Loargys Summary of Product Characteristics (Nov 2025)
- Diaz GA, et al. Clinical effect and safety profile of pegzilarginase in patients with arginase 1 deficiency. J Inherit Metab Dis. 2021 Jul;44(4):847-856.
- Russo SR et al. Efficacy and safety of pegzilarginase in arginase 1 deficiency (PEACE): a phase 3, randomized, double-blind, placebo-controlled, multi-centre trialeClinicalMedicine.2024;68:102405.
- Sanchez Russo R et al. Pegzilarginase in Arginase 1 Deficiency: Results of the PEACE Pivotal Phase 3 Clinical Trial PAS4A-2674) . Oral presentation at the SSIEM Annual Symposium, Freiburg, Germany 30 August- 2 September 2022.
Rutsch F et al. Improved clnically meaningful treatment outcomes of pegzilarginase during longer-term treatment: Final functional mobility analysis from the Phase 3 PEACE trial. Poster presented at the SSIEM Annual Symposium, Porto, Portugal 3-6 September 2024
