UK – The National Institute for Health and Care Excellence (NICE), has discouraged the use of Orchard Therapeutics’ gene therapy Libmeldy.
NICE highlighted that although the clinical trial evidence suggests the drug improves motor and cognitive function and could correct the enzyme deficiency caused by MLD, its long-term stabilization of symptoms was very uncertain.
Ortho Therapeutics, a global gene therapy leader, developed Libmeldy for the treatment of metachromatic leukodystrophy (MLD) in children.
MLD is a rare hereditary disease characterized by accumulation of fats called sulfatides and causes the destruction of the protective fatty layer (myelin sheath) surrounding the nerves in both the central nervous system and the peripheral nervous system.
The disease is classified into three categories late-infantile MLD, juvenile MLD, and adult MLD with all having varying symptoms like difficulty in talking, seizures, difficulty walking, personality changes, and behavior changes.
Patients with the late-infantile form of MLD, which is the most common and rapidly progressing type, deteriorate quickly and have a life expectancy of five to eight years old.
Children with early juvenile MLD have a life expectancy of between ten and twenty years after symptoms onset.
MLD is an autosomal recessive genetic disorder and most of the time if a child is affected, their parents are carriers, meaning each parent will have one changed (mutated) copy and one normal copy of the ASA gene, but will not have symptoms.
The true prevalence rate of MLD is unknown, but is estimated to be between 1 in 40,000 and 1 in 160,000. The Navajo region have a higher prevalence rate of 1 in every 2,500 people though in certain populations in the Middle East, these numbers may be even higher.
There are currently no approved therapies for MLD, so management focuses on symptomatic treatment hence.
Hematopoietic stem cell transplantation (HSCT) has been reported to stabilize central demyelination and delay disease progression in some patients with juvenile MLD who are presymptomatic or at a very early symptomatic stage.
According to Research and Markets, the future competitive landscape of MLD is estimated to be very strong and prior to the update of non-recommendation of the drug, Libmeldy was among the key emerging drugs alongside Takeda’s TAK-611.
Despite the NICE rejection, Orchard has proposed a patient access scheme to make Libmeldy available to the National Health Services with a confidential discount.