Maladie de Batten

Overview

Batten disease, also called neuronal ceroid lipofuscinosis (NCL), is a group of inherited disorders in which cells—especially cells in the brain and retina—cannot properly clear certain cellular materials. The resulting buildup damages neurons. Different gene variants cause different NCL subtypes, with onset ranging from infancy to adulthood, although many forms begin in childhood. Common features include developmental regression, seizures, loss of vision, worsening movement and thinking abilities, and shortened life expectancy; the pace and severity vary substantially by subtype. GeneReviews overview

There is not yet a proven cure for any form of Batten disease. Care therefore combines seizure management, nutrition and swallowing support, physical and occupational therapy, vision support, and other symptom-directed services. For CLN2 disease specifically, intracerebroventricular enzyme replacement with cerliponase alfa can slow loss of motor and language function, but it does not reverse established disease or constitute a cure. GeneReviews targeted therapy

Scope of Recent Research (2020–present)

Research since 2020 has been active and increasingly focused on delivering a working copy of the faulty gene directly to the brain, spinal cord, and eye; correcting RNA splicing defects; and finding treatments that reach both neurological and body-wide disease. The field has moved from compelling animal studies to early human trials in CLN5, CLN6, and CLN7 disease, but the clinical evidence remains too early and too small to establish durable disease arrest, reversal, or cure. CLN5 trial CLN6 trial CLN7 trial

Major Breakthroughs and Emerging Therapies

Gene replacement therapy is the dominant curative strategy. Most programs use adeno-associated virus (AAV), a modified virus that carries a functional gene into cells. In CLN5 disease, Neurogene’s NGN-101 delivers a codon-optimized CLN5 gene by injection into the brain’s fluid spaces and into the eye, explicitly aiming to address both neurological decline and retinal degeneration. This dual-route design was supported by a CLN5 sheep study in which intracerebroventricular plus intravitreal AAV9 treatment slowed or halted clinical progression in treated animals, reduced brain-volume loss, and sustained visual function over 24 months. NGN-101 trial CLN5 sheep gene therapy

More recent preclinical work has refined this approach rather than simply increasing dose. In a 2026 CLN5 mouse study, an AAV9 vector using a neuron-oriented promoter improved pathology, movement, and survival, while a broader promoter was less effective; treatment also normalized blood neurofilament light, a potential marker of nerve-cell injury. This result suggests that selecting which cells express the replacement gene may be as important as vector dose or timing. CLN5 AAV and biomarker study For CLN7 disease, intrathecal AAV9/MFSD8 gene replacement restored lysosomal function in patient-derived cells and improved behavior and median survival in mice, providing the foundation for later human testing. CLN7 preclinical AAV study

CLN1 research illustrates both the promise and difficulty of treating a rapidly progressive, whole-central-nervous-system disease. A 2025 study engineered the missing PPT1 enzyme to improve secretion and uptake by neighboring cells (“cross-correction”), packaged it in a neurotropic AAV capsid, and found long-lasting neurological benefit in CLN1 mice; a sheep biodistribution study found widespread brain expression without adverse effects over the study period. Engineered PPT1 AAV study A separate CLN1 mouse study used lentiviral gene transfer in blood-forming stem cells, which can generate microglia-like cells in the brain, and reported greater benefit when intravenous and intracerebroventricular cell delivery were combined. This is experimental cell-and-gene therapy, not a human treatment. CLN1 stem-cell gene therapy

RNA therapeutics offer a more mutation-specific route. Antisense oligonucleotides (ASOs) are short synthetic nucleic acids that can alter how RNA is spliced before it is translated into protein. In CLN3 models carrying the common exon 7–8 deletion, splice-switching ASOs have been used to generate a shorter, potentially functional CLN3 transcript. A 2020 mouse study demonstrated therapeutic activity after central nervous system delivery, while a 2025 pig study found that a single injection into the eye produced long-lasting exon skipping and improved electroretinogram measures of retinal function. These results are important proof of concept, but they are not yet evidence of clinical efficacy in people. CLN3 ASO mouse study CLN3 ASO pig study

Small-molecule repurposing remains a lower-burden complementary strategy rather than a demonstrated cure. In a 2026 two-patient CLN3 case report, 18 months of off-label oral miglustat was associated with improved visual acuity and stabilization on a Batten disease rating scale, without major reported adverse effects. Because this was an uncontrolled report involving two siblings, it cannot establish that miglustat caused the improvements; larger, longer controlled studies are needed. Miglustat CLN3 case report

Clinical Trials and Experimental Approaches

The clearest human gene-therapy results so far come from the phase 1 CLN7 study at the University of Texas Southwestern. Four children received one intrathecal dose of AAV9/CLN7, which supplies the MFSD8 gene. The 2025 report described evidence that the high dose could be administered safely under a specified immunosuppression regimen and reported preliminary evidence of efficacy, while emphasizing the need for continued immune monitoring and longer follow-up. The registry lists the study as active but not recruiting, with four enrolled participants and estimated completion in 2029. CLN7 phase 1 report CLN7 trial record

For CLN5, Neurogene’s NGN-101 phase 1/2 study is active but not recruiting. It has enrolled six children and evaluates one-time AAV9 treatment delivered both intracerebroventricularly and intravitreally, with motor, language, visual, and cognitive outcomes followed for five years. No peer-reviewed participant outcomes were listed in the trial registry. NGN-101 trial record A CLN6 phase 1/2b program sponsored by the Charlotte and Gwenyth Gray Foundation and collaborating with the University of California, San Diego was listed as not yet recruiting in its May 2026 update; it proposes a single intrathecal dose of scAAV9.CB.CLN6 in 12 participants, followed by two years of assessments and long-term follow-up. CLN6 trial record

Methodologies and Scientific Approaches

Researchers use patient fibroblasts, induced cell models, knockout mice, and larger animal models such as sheep, dogs, and pigs to test whether a therapy restores the missing protein, reduces storage material and inflammation, preserves retinal and brain cells, improves movement or vision, and extends survival. Larger animals are particularly valuable because their brains and eyes better test whether a treatment can spread across clinically relevant tissue volumes. CLN5 sheep gene therapy Engineered PPT1 AAV study CLN3 ASO pig study

Delivery is a central technical challenge. Studies are comparing injection into cerebrospinal fluid through the spine, direct intracerebroventricular brain delivery, and intravitreal eye injection, because brain-only treatment may leave vision loss or peripheral disease insufficiently treated. Trials and laboratory studies increasingly combine clinical scales, cognitive and motor testing, MRI, electroencephalography, retinal electrophysiology, vector biodistribution, and biomarkers such as neurofilament light to measure whether a therapy is changing disease biology as well as symptoms. CLN7 trial record CLN5 AAV and biomarker study

Leading Institutions and Funding

Key clinical leaders include the University of Texas Southwestern, which sponsors the CLN7 phase 1 trial; Neurogene, sponsor of the CLN5 NGN-101 trial; and the Charlotte and Gwenyth Gray Foundation with the University of California, San Diego, which are advancing the CLN6 program. CLN7 trial record NGN-101 trial record CLN6 trial record

Preclinical efforts are also driven by cross-sector collaborations. The recent CLN5 work brought together University College London, King’s College London, the University of Oxford, and the UK Dementia Research Institute; the CLN1 PPT1 program included academic groups and Spark Therapeutics; and the CLN3 retinal ASO work involved Rosalind Franklin University, University of Michigan, Sanford Research, University of Iowa, and Ionis Pharmaceuticals. Philanthropic organizations are unusually important in this ultra-rare field: the CLN7 human study reported support from the Batten’s Hope Foundation, Mila’s Miracle Foundation, Children’s Health Dallas, and philanthropic gifts to UT Southwestern. CLN5 AAV and biomarker study Engineered PPT1 AAV study CLN3 ASO pig study CLN7 phase 1 report

Strengths, Limitations, and Challenges

The major strength of current research is that Batten diseases are usually caused by defects in a single gene, making them conceptually suitable for gene replacement or RNA correction. Encouragingly, recent studies show meaningful biological rescue across several subtypes and animal species, and early-phase human CLN7 data provide an initial safety and feasibility signal. CLN7 preclinical AAV study CLN7 phase 1 report However, “rescue” in a mouse or sheep does not establish that a therapy can reverse advanced human neurodegeneration, preserve vision for decades, or safely treat every affected brain and spinal-cord region.

Important obstacles include the need to intervene before extensive neuron loss, limited ability of vectors to reach the whole nervous system, immune responses to the AAV capsid or newly produced protein, uncertainty over re-dosing, and the burden of neurosurgical or spinal delivery. The small number of patients in each subtype also makes rigorous trials difficult and increases uncertainty around natural-history comparisons. CLN1 research further indicates that peripheral and enteric nervous-system disease may need attention alongside the brain, making a one-route treatment less likely to be sufficient for every subtype. Engineered PPT1 AAV study CLN1 stem-cell gene therapy

Outlook and Future Directions

À la date du 10 septembre 2026, la recherche sur la maladie de Batten se rapproche d’un traitement modificateur de la maladie, potentiellement durable, par rapport à 2020, mais elle n’est pas encore suffisamment proche pour prétendre à une cure chez l’homme. Les jalons les plus importants à surveiller sont un suivi de phase 1 CLN7 sur plusieurs années, les premiers résultats rapportés de l’étude NGN-101 CLN5, l’initiation et le recrutement de l’essai CLN6, et la confirmation que les thérapies peuvent préserver à la fois les fonctions neurologiques et visuelles lorsqu’elles sont administrées précocément. Une cure crédible nécessitera une sécurité soutenue, un bénéfice durable et des preuves d’une progression arrêtée ou inversée chez des patients adéquatement suivis — et non seulement des marqueurs biologiques améliorés ou une survie chez l’animal. CLN7 trial record NGN-101 trial record CLN6 trial record

Références

• Neuronal Ceroid Lipofuscinoses Overview — GeneReviews®, 2025.
• Gene Therapy Study for Children With CLN5 Batten Disease (NCT05228145) — ClinicalTrials.gov, 2024.
• Gene Therapy Trial for CLN6 Batten Disease (NCT07582484) — ClinicalTrials.gov, 2026.
• Study for the Treatment for CLN7 Disease (NCT04737460) — ClinicalTrials.gov, 2025.
• Efficacy of dual intracerebroventricular and intravitreal CLN5 gene therapy in sheep — Murray et al., 2023.
• Brain-directed AAV gene therapy rescues a CLN5 mouse model and normalizes a plasma biomarker — Liu et al., 2026.
• AAV9/MFSD8 gene therapy is effective in preclinical models of CLN7 disease — Chen et al., 2022.
• AAV-delivered PPT1 provides long-term neurological benefits in CLN1 mice and achieves therapeutic levels in sheep brain — Massaro et al., 2025.
• An innovative hematopoietic stem-cell gene-therapy approach benefits CLN1 disease in mice — PubMed, 2023.
• Therapeutic efficacy of antisense oligonucleotides in mouse models of CLN3 Batten disease — PubMed, 2020.
• Therapeutic antisense oligonucleotide mitigates retinal dysfunction in a pig model of CLN3 Batten disease — Stratton et al., 2025.
• Visual recovery and neurological stabilization following miglustat treatment in pediatric CLN3 disease — Dutton et al., 2026.
• First-in-human high-dose AAV9 intrathecal gene therapy for pediatric CLN7 disease — Greenberg et al., 2025.