First gene therapy to receive full EU marketing authorization for eligible MLD patients. One-time treatment with Libmeldy has been shown to preserve motor and cognitive function.

Orchard Therapeutics, a global gene therapy leader, and its research alliance partners Fondazione Telethon and Ospedale San Raffaele, today announced that the European Commission (EC) granted full (standard) market authorization for Libmeldy (autologous CD34+ cells encoding the ARSA gene), a lentiviral vector-based gene therapy approved for the treatment of metachromatic leukodystrophy (MLD), characterized by biallelic mutations in the ARSA gene leading to a reduction of the ARSA enzymatic activity in children with i) late infantile or early juvenile forms, without clinical manifestations of the disease, or ii) the early juvenile form, with early clinical manifestations of the disease, who still have the ability to walk independently and before the onset of cognitive decline. Libmeldy is the first therapy approved for eligible patients with early-onset MLD.

MLD is a very rare, fatal genetic disorder caused by mutations in the ARSA gene which lead to neurological damage and developmental regression. In its most severe and common forms, young children rapidly lose the ability to walk, talk and interact with the world around them, and most pass away before adolescence. Libmeldy is designed as a one-time therapy that aims to correct the underlying genetic cause of MLD, offering eligible young patients the potential for long-term positive effects on cognitive development and maintenance of motor function at ages at which untreated patients show severe motor and cognitive impairments.

“Today’s EC approval of Libmeldy opens up tremendous new possibilities for eligible MLD children faced with this devastating disease where previously no approved treatment options existed,” said Bobby Gaspar, M.D., Ph.D., chief executive officer of Orchard. “Libmeldy is Orchard’s first product approval as a company, and I am extremely proud of the entire team who helped achieve this milestone. We are grateful for and humbled by the opportunity to bring this remarkable innovation to young eligible patients in the EU.”

With Libmeldy, a patient’s own hematopoietic stem cells (HSCs) are selected, and functional copies of the ARSA gene are inserted into the genome of the HSCs using a self-inactivating (SIN) lentiviral vector before these genetically modified cells are infused back into the patient. The ability of the gene-corrected HSCs to migrate across the blood-brain barrier into the brain, engraft, and express the functional enzyme has the potential to persistently correct the underlying disease with a single treatment.

“The EC approval of Libmeldy comes more than a decade after the first patient was treated in clinical trials performed at our Institute, and ushers in a remarkable and long-awaited shift in the treatment landscape for eligible MLD patients, said Luigi Naldini, M.D, Ph.D., director of the San Raffaele-Telethon Institute for Gene Therapy (SR-Tiget) in Milan, Italy. “Our team at SR-Tiget has been instrumental in advancing the discovery and early-stage research of this potentially transformative therapy to clinical trials in support of its registration through more than 15 years of studies supported by Fondazione Telethon and Ospedale San Raffaele, and we are extremely proud of this achievement and what it means for patients and the field of HSC gene therapy.”

“MLD is a heart-breaking disease that causes immeasurable suffering and robs children of the chance of life,” said Georgina Morton, chairperson of ArchAngel MLD Trust. “As a community, we have been desperate for a treatment for young MLD patients, and we are incredibly excited to now have such a ground-breaking option approved in the EU.”

The marketing authorization for Libmeldy is valid in all 27 member states of the EU as well as the UK, Iceland, Liechtenstein and Norway. Orchard is currently undertaking EU launch preparations related to commercial drug manufacturing, treatment site qualification and market access.

Data Supporting the Clinical and Safety Profile of Libmeldy

The marketing authorization for Libmeldy is supported by clinical studies in both pre- and early- symptomatic, early-onset MLD patients performed at the SR-Tiget. Early-onset MLD encompasses the disease variants often referred to as late infantile (LI) and early juvenile (EJ). Clinical efficacy was based on the integrated data analysis from 29 patients with early-onset MLD who were treated with Libmeldy prepared as a fresh (non-cryopreserved) formulation. Results of this analysis indicate that a single-dose intravenous administration of Libmeldy is effective in modifying the disease course of early-onset MLD in most patients.

Clinical safety was evaluated in 35 patients with MLD (the 29 patients from the integrated efficacy analysis as well as six additional patients treated with the cryopreserved formulation of Libmeldy). Safety data indicate that Libmeldy was generally well-tolerated. The most common adverse reaction attributed to treatment with Libmeldy was the occurrence of anti-ARSA antibodies (AAA) reported in five out of 35 patients. Antibody titers in all five patients were generally low and no negative effects were observed in post-treatment ARSA activity in the peripheral blood or bone marrow cellular subpopulations, nor in the ARSA activity within the cerebrospinal fluid. In addition to the risks associated with the gene therapy, treatment with Libmeldy is preceded by other medical interventions, namely bone marrow harvest or peripheral blood mobilization and apheresis, followed by myeloablative conditioning, which carry their own risks. During the clinical studies, the safety profiles of these interventions were consistent with their known safety and tolerability.

About MLD and Libmeldy

MLD is a rare and life-threatening inherited disease of the body’s metabolic system occurring in approximately one in every 100,000 live births. MLD is caused by a mutation in the arylsulfatase-A (ARSA) gene that results in the accumulation of sulfatides in the brain and other areas of the body, including the liver, gallbladder, kidneys, and/or spleen. Over time, the nervous system is damaged, leading to neurological problems such as motor, behavioral and cognitive regression, severe spasticity and seizures. Patients with MLD gradually lose the ability to move, talk, swallow, eat and see. In its late infantile form, mortality at five years from onset is estimated at 50% and 44% at 10 years for juvenile patients.¹

Libmeldy (autologous CD34+ cell enriched population that contains hematopoietic stem and progenitor cells (HSPC) transduced ex vivo using a lentiviral vector encoding the human arylsulfatase-A (ARSA) gene), also known as OTL-200, is approved in the European Union for the treatment of MLD in eligible early-onset patients. In the U.S., OTL-200 is an investigational therapy which has not been approved by the U.S. Food and Drug Administration (FDA) for any use. Libmeldy was acquired from GSK in April 2018 and originated from a pioneering collaboration between GSK and the Hospital San Raffaele and Fondazione Telethon, acting through their joint San Raffaele-Telethon Institute for Gene Therapy in Milan, initiated in 2010.