Preclinical studies of gene replacement therapy for CDKL5 deficiency disorder

• Published in: Molecular therapy Vol. 32; no. 10; pp. 3331 - 3345
• Main Authors: Voronin, Gregory, Narasimhan, Jana, Gittens, Jamila, Sheedy, Josephine, Lipari, Philip, Peters, Melinda, DeMarco, Steven, Cao, Liangxian, Varganov, Yakov, Kim, Min Jung, Pear, Lisset, Fotouh, Eman, Sinha, Supriya, Ray, Balmiki, Wu, Michael C., Yalamanchili, Padmaja, Southgate, Christopher, Pick, Joseph, Saadipour, Khalil, Jung, Stephen, Lee, Jeanee, Mollin, Anna, Welch, Ellen M., Wu, Zhijian, Weetall, Marla
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 02.10.2024
• Subjects: AAV9; Animals; biodistribution; Brain - metabolism; CDD; CDKL5; Dependovirus - genetics; Disease Models, Animal; drug discovery and development; Epileptic Syndromes - genetics; Epileptic Syndromes - therapy; Gene Expression; gene therapy; Genetic Therapy - methods; Genetic Vectors - administration & dosage; Genetic Vectors - genetics; Humans; Male; Mental Retardation, X-Linked - genetics; Mental Retardation, X-Linked - therapy; Mice; Microtubule-Associated Proteins - genetics; Microtubule-Associated Proteins - metabolism; molecular therapeutics; mouse models of disease; pharmacodynamics; Phosphorylation; Promoter Regions, Genetic; Protein Serine-Threonine Kinases - genetics; Protein Serine-Threonine Kinases - metabolism; route of administration; Spasms, Infantile - genetics; Spasms, Infantile - metabolism; Spasms, Infantile - therapy; Synapsins - genetics; Synapsins - metabolism; Tissue Distribution; mouse models of disease; CDD; biodistribution; molecular therapeutics; CDKL5; pharmacodynamics; drug discovery and development; gene therapy; AAV9; route of administration
• ISSN: 1525-0016; 1525-0024; 1525-0024
• DOI: 10.1016/j.ymthe.2024.07.012

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a rare neurodevelopmental disorder caused by a mutation in the X-linked CDKL5 gene. CDKL5 is a serine/threonine kinase that is critical for axon outgrowth and dendritic morphogenesis as well as synapse formation, maturation, and maintenance. This disorder is characterized by early-onset epilepsy, hypotonia, and failure to reach cognitive and motor developmental milestones. Because the disease is monogenic, delivery of the CDKL5 gene to the brain of patients should provide clinical benefit. To this end, we designed a gene therapy vector, adeno-associated virus (AAV)9.Syn.hCDKL5, in which human CDKL5 gene expression is driven by the synapsin promoter. In biodistribution studies conducted in mice, intracerebroventricular (i.c.v.) injection resulted in broader, more optimal biodistribution than did intra-cisterna magna (i.c.m.) delivery. AAV9.Syn.hCDKL5 treatment increased phosphorylation of EB2, a bona fide CDKL5 substrate, demonstrating biological activity in vivo. Our data provide proof of concept that i.c.v. delivery of AAV9.Syn.hCDKL5 to neonatal male Cdkl5 knockout mice reduces pathology and reduces aberrant behavior. Functional improvements were seen at doses of 3e11 to 5e11 vector genomes/g brain, which resulted in transfection of ≥50% of the neurons. Functional improvements were not seen at lower doses, suggesting a requirement for broad distribution for efficacy. [Display omitted] Weetall and colleagues demonstrate the use of gene therapy for CDKL5 deficiency disorder (CDD). CDD is caused by a mutation in the CDKL5 gene and is characterized by early-onset epilepsy and severe cognitive and motor impairment. I.c.v. delivery of the vector AAV9.Syn.hCDKL5 to Cdkl5 knockout mice dose-dependently reduced pathology.