First EU Pharmacological Approval in Pediatric cALD: Regulatory Milestone, Reimbursement Proof Still Pending

EC Grants Marketing Authorization for NEZGLYAL in cALD

The European Commission has granted marketing authorization under exceptional circumstances for NEZGLYAL® (leriglitazone), an orally bioavailable, brain-penetrating selective PPAR gamma agonist. Developed by Minoryx Therapeutics and commercialized by Neuraxpharm Group in Europe, this therapy is the first pharmacological treatment approved in the EU for male cALD patients aged 2-12 years with Gadolinium-negative brain lesions. The approval, announced on September 21, 2026, is based on results from the Phase 2/3 NEXUS study and real-world evidence, addressing a critical unmet need for early intervention in this rapidly progressing neurodegenerative disease. The first European launch is expected in Germany by the end of 2026.

• NEZGLYAL® (leriglitazone) represents a significant breakthrough as the first pharmacological treatment approved in the European Union for cerebral Adrenoleukodystrophy (cALD). This approval specifically targets male patients aged 2-12 years with non-Gadolinium (Gd)-enhancing brain lesions and a Neurological Functional Score (NFS) of 0 or 1, offering a crucial early intervention option where previously only invasive procedures like hematopoietic stem cell transplantation were available for more advanced cases.
• The marketing authorization by the European Commission is underpinned by robust clinical data from the Phase 2/3 NEXUS study, which demonstrated that paediatric cALD patients achieved clinical and radiological stability after over 96 weeks of treatment. This evidence was further supported by additional real-world data from compassionate use programs and findings from the ADVANCE trial, collectively validating leriglitazone's clinical benefit in cALD patients.
• cALD is a severe, rapidly progressing neurodegenerative disease that can lead to acute neurological decline and death within three to four years. Leriglitazone offers a non-invasive, daily oral treatment that is disease-modifying. Following the positive CHMP opinion in July 2026, Neuraxpharm, under license from Minoryx, plans the initial European launch in Germany by the end of 2026, with ongoing development efforts to potentially expand the label within X-ALD and other orphan indications.

NEZGLYAL® Transforms the cALD Treatment Landscape

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has long served as the foundational intervention for cerebral adrenoleukodystrophy (cALD), with published data confirming that early-stage disease at the time of transplant is a critical determinant of outcomes. An observational study of 59 patients (median age 8 years) demonstrated that survival free of major functional disabilities at 4 years was significantly higher in early disease cohorts (66%) versus advanced disease (41%; P = .015), while transplant-related mortality was 7% in early disease versus 22% in advanced disease. Neurologic function stabilization, measured by change from baseline in neurological function score (NFS) and Loes score at 24 months, was markedly better in early-stage patients. Graft failure incidence was significantly higher with unrelated umbilical cord grafts versus matched related donors (P = .039), and acute graft-versus-host disease (GVHD) and graft failure rates varied by conditioning regimen. A separate retrospective analysis of 10 allo-HSCT patients reported a 3-year overall survival (OS) of 90.0% (95% CI: 69.4–100.0) and event-free survival (EFS) of 65.6% (95% CI: 35.6–98.4), with EFS significantly superior in patients without MRI abnormalities at disease onset (P = .013) and without neurological functional symptoms before HSCT (P = .023).

Lentiviral gene therapy with elivaldogene autotemcel (eli-cel; Lenti-D), consisting of autologous CD34+ cells transduced with a lentiviral vector containing ABCD1 complementary DNA, has emerged as an alternative for patients lacking an HLA-matched sibling donor. In a phase 2–3 study (ALD-102), 32 boys with early-stage cALD and active MRI inflammation received eli-cel; at month 24, none of the 29 patients who completed the study had major functional disabilities, and overall survival was 94%. At a median follow-up of 6 years, the NFS was stable relative to baseline in 30 of 32 patients (94%), and 26 patients (81%) had no major functional disabilities. Eli-cel received its first regulatory approval in the EU in July 2021 for early cALD in patients under 18 years of age with an ABCD1 genetic mutation for whom an HLA-matched sibling HSC donor is not available.

The long-term safety profile of eli-cel has, however, become a central concern. Across two completed phase 2–3 studies (ALD-102 and ALD-104) and an ongoing follow-up study (LTF-304), hematologic cancer developed in 7 of 67 patients: myelodysplastic syndrome (MDS) with unilineage dysplasia in 2 patients at 14 and 26 months; MDS with excess blasts in 3 patients at 28, 42, and 92 months; MDS in 1 patient at 36 months; and acute myeloid leukemia (AML) in 1 patient at 57 months. In 6 patients with available data, predominant clones contained lentiviral vector insertions at multiple loci, including at either MECOM-EVI1 (in 5 patients) or PRDM16 (in 1 patient); 6 of the 7 patients also harbored somatic mutations (KRAS, NRAS, WT1, CDKN2A or CDKN2B, or RUNX1). Of the 5 patients with MDS with excess blasts or MDS with unilineage dysplasia who underwent allogeneic HSCT, 4 remain free of MDS without recurrence of cALD symptoms, and 1 patient died from presumed GVHD 20 months after HSCT. Insertional oncogenesis therefore remains an ongoing risk associated with viral vector integration, shaping the benefit–risk calculus for gene therapy in this population.

Addressing Critical Unmet Needs in Early cALD Intervention

Effective intervention in cALD remains constrained by a narrow therapeutic window, the limited availability of matched donors, and emerging safety signals from gene therapy approaches. Early identification and timely access to treatment are critical determinants of outcome, yet multiple structural and biological barriers complicate both.

• Timing and patient selection for HSCT: Hematopoietic cell transplant (HCT) is the treatment of choice for cerebral ALD, but optimal outcomes depend on early-stage disease and the absence of major neurological disability. Symptomatic patients fare poorly, with lower survival and rapid deterioration of neurologic function, while superior outcomes are seen in neurologically asymptomatic boys transplanted at a young age. Current eligibility assessment relies on MRI-based Loes scoring and neurological evaluations, which poorly differentiate advanced stages or atypical lesion patterns.

• Donor availability and HLA matching constraints: Many patients lack suitable HLA-matched related donors and must rely on alternative sources. In umbilical cord blood transplantation (UCBT), allele-level HLA mismatches — not captured by conventional antigen-level matching — significantly impact outcomes: within the conventional 6/6 match stratum, 5-year overall survival was 88% for allele-matched versus 42% for allele-mismatched recipients (P < .01), and graft failure rates were 8% versus 30% (P = .05), respectively. Haploidentical HSCT has been explored as an alternative but remains preliminary, with one death reported among eight patients.

• Insertional oncogenesis risk with lentiviral gene therapy: Elivaldogene autotemcel (eli-cel) gene therapy has demonstrated efficacy, with 81% of patients having no major functional disabilities at a median follow-up of 6 years; however, hematologic cancer developed in 7 of 67 patients across clinical studies. Cases included myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), associated with clonal lentiviral vector insertions at oncogenic loci — predominantly MECOM-EVI1 (in 5 patients) and PRDM16 (in 1 patient) — combined with acquisition of somatic mutations. The oncogenic risk has been mechanistically linked to the use of a potent viral MNDU3 promoter, potentially compounded by intensive conditioning and growth-factor support.

• Biomarker limitations in clinical decision-making: Routine surveillance relies on MRI and neurological scoring, which remain inadequate for advanced or atypical disease presentations. Blood neurofilament light chain (NfL) has been identified as a complementary biomarker: pre-treatment NfL ≤ 113 pg/ml correlates with CALD stabilization, while NfL > 243 pg/ml associates with major progression irrespective of baseline Loes score. However, this evidence derives from a retrospective cohort of only 14 patients, limiting its immediate clinical applicability.

• Surveillance gaps in presymptomatic and adult populations: Newborn screening has increased the number of presymptomatic individuals under observation, but clinical surveillance protocols vary. Adults with ALD/adrenomyeloneuropathy (AMN) face significant provider, patient, and systems-based barriers to appropriate longitudinal care, including lack of awareness of the importance of neurologic management, and standardized assessment frameworks for this population remain underdeveloped.

Beyond cALD: Leriglitazone's Expanding Clinical Development

Leriglitazone, a brain-penetrant PPARγ agonist, has demonstrated activity across multiple neuroinflammatory and neurodegenerative pathways, supporting its investigation beyond cALD. The ADVANCE trial established its clinical profile in adrenomyeloneuropathy (AMN), and preclinical work has further implicated leriglitazone in conditions involving oxidative stress, mitochondrial dysfunction, and demyelination. Evidence from a Cochrane systematic review also identifies leriglitazone as one of the pharmacological agents tested in Friedreich ataxia (FRDA).

A New Dawn for Early Childhood cALD Treatment

The European Commission's marketing authorization for NEZGLYAL® (leriglitazone) marks a significant advancement for children living with cerebral adrenoleukodystrophy (cALD). This approval introduces the first pharmacological treatment specifically for male cALD patients aged 2-12 years with Gadolinium-negative brain lesions, addressing a profound unmet need in a disease characterized by rapid, devastating neurodegeneration.

Historically, hematopoietic stem-cell transplantation (HSCT) has been the primary intervention, but its high morbidity and limited availability underscore the urgent demand for alternative, less invasive therapies. Leriglitazone, an orally bioavailable and brain-penetrant selective PPAR gamma agonist, offers a novel approach. Its mechanism of action involves modulating critical pathways implicated in neuroinflammation, oxidative stress, and mitochondrial dysfunction, all central to cALD pathogenesis. By targeting patients in the early, Gadolinium-negative stage of the disease, the strategy aims to intervene before irreversible neurological damage occurs. Research indicates that early lesions progress rapidly in younger patients, making this window of opportunity crucial for potentially decelerating disease progression and preserving neurological function.

This strategic focus on early intervention, coupled with the convenience of an oral therapy, positions leriglitazone to potentially redefine the standard of care for this vulnerable pediatric population. It offers a more accessible option that could either delay the need for HSCT or serve as a bridge therapy. However, it is important to acknowledge the context of this approval. The authorization was granted under 'exceptional circumstances,' and the supporting data from the NEXUS study involved an interim analysis of a relatively small, open-label cohort. While promising, the long-term efficacy and safety profile in a larger, controlled setting will require continued investigation. Furthermore, the drug's prior performance in the ADVANCE trial for adrenomyeloneuropathy, where it did not meet its primary endpoint, suggests that its therapeutic benefits may be highly specific to certain patient populations or disease stages. Clinicians will also need to manage known class-effect adverse events, such as weight gain and peripheral edema, which were observed in trials. Despite these considerations, the introduction of leriglitazone represents a beacon of hope, offering a much-needed therapeutic option and paving the way for further research into early disease modification in cALD.