Cystinosis is a rare inherited recessive disease belonging to the family of Lysosomal Storage Disorders and is characterized by lysosomal accumulation of cystine in all the cells of the body leading to multi-organ failure. Cystinosis has a devastating impact on the affected individuals, primarily children, and young adults, even with cysteamine treatment. The prevalence of cystinosis is 1 in 100,000 to 1 in 200,000. The gene involved in cystinosis is the gene CTNS that encodes for the transmembrane lysosomal cystine transporter - cystinosin. The current standard of care does not prevent the progression of the disease and significantly impacts the quality of life of patients with cystinosis.~For this study, up to 6 subjects meeting eligibility criteria will be transplanted following a 3-cohort staggered treatment design with 2 subjects per cohort. The first 2 cohorts will consist of 4 adults (18 years or older), potentially followed by a cohort consisting of 2 adolescents or adults (> 14 years old). Following the informed consent process, enrolled subjects will be screened to confirm full eligibility for participation. Eligible subjects will undergo hematopoietic stem cell (HSC) mobilization and collection (leukapheresis). A portion of cells will be kept as back-up for rescue purpose if necessary, and a portion will be ex vivo gene-modified with a lentiviral vector, pCCL-CTNS or pCDY.EFS.CTNS.T260I, to express CTNS gene (product name: CTNS-RD-04). Clinical manufacturing for patients in Cohort 3 will introduce a transduction enhancer LentiBOOST (product name for these patients will be CTNS-RD-04-LB, where the suffix -LB stands for LentiBOOST). The subjects will receive marrow cytoreduction with busulfan prior to infusion of CTNS-RD-04. Subjects will discontinue cysteamine treatment during the assessment period. The assessment follow-up period will include an initial 2 years of active end-point evaluations, where the subjects will be evaluated at 3-, 6-, 9-, 12-, 18- and 24-months post-transplantation. A Long-Term Follow-Up study (LTFU) for a total 15-year follow-up period will be offered to all subjects.~The objectives of this Phase 1/2 clinical study are to assess the safety/tolerability of CTNS-RD-04, and its efficacy through a number of clinical, molecular and biochemical assessments.
This study is a Phase 1/2 clinical trial that will assess the safety and efficacy of enriched gene-corrected hematopoietic stem cells isolated from patients affected with cystinosis. (Investigational Product: CTNS-RD-04 or CTNS-RD-04-LB, where the suffix -LB stands for LentiBOOST)