by Morquio Syndrome, also known as Mucopolysaccharidosis Type IV (MPS-IV), is a rare genetic disorder that prevents the body from breaking down sugars it naturally produces. These sugars accumulate in cells and blood, resulting in skeletal abnormalities and other symptoms. If left untreated, Morquio Syndrome can lead to severe physical and cognitive disabilities as well as early death. The exact prevalence of Morquio Syndrome is unknown, but it is estimated to affect 1 in every 200,000 newborns worldwide.
Causes and Symptoms of Morquio Syndrome
Morquio Syndrome is caused by a deficiency in the enzymes N-acetylgalactosamine-6-sulfatase (GALNS) or β-galactosidase. This prevents the body from properly breaking down glycosaminoglycans (GAGs), which are sugar chains essential for the healthy development of bone and tissue. As GAGs accumulate to high levels in tissues and organs, it causes damage over time. Common symptoms of Morquio Syndrome include skeletal abnormality such as shortened neck or torso, spinal curvature, hip issues, and spine abnormalities. Other symptoms can include hearing loss, respiratory problems, heart issues, liver and spleen enlargement, clouding of the cornea, and developmental delays. Due to these complications, individuals with Morquio Syndrome often require wheelchair assistance by their early teens and have a reduced life expectancy.
Current Morquio Syndrome (MPS-IV) Drug and Their Limitations
Currently, there is no cure for Morquio Syndrome (MPS-IV) Drug. Treatment focuses on managing symptoms and improving quality of life. Surgical interventions can help correct skeletal abnormalities and respiratory issues. Physical and occupational therapy aims to maintain mobility and function. Hearing aids may help hearing loss. However, many standard treatments only manage rather than halt the progression of the disease. Bone marrow transplants have been attempted but see limited success due to bone and cartilage already being affected prior to transplant. Enzyme replacement therapy (ERT) using the enzyme missing in Morquio Syndrome is the standard treatment, but it has significant limitations. Given intravenously every week, ERT fails to fully cross the blood-brain barrier and does not correct existing damage to tissues and organs. As a result, Morquio Syndrome patients on ERT continue to experience deterioration in mobility, respiratory function, and cognition over time.
Promising New Oral Therapy Shows Potential
A promising new oral therapy called vosoritide is currently in late-stage clinical trials and shows potential to overcome some of the limitations of ERT. Vosoritide is a small molecule C-type natriuretic peptide (CNP) analogue developed by BioMarin Pharmaceutical Inc. to target the growth plate, the area of active bone growth in children. In Morquio Syndrome (MPS-IV) Drug, the growth plate is disrupted due to excessive GAG accumulation. Vosoritide works by mimicking the effects of CNP, which regulates growth plate function. It enables the growth plate to withstand the effects of GAG storage and resume normal growth. In clinical trials so far, vosoritide has demonstrated an ability to increase annual growth rates when taken daily by mouth in conjunction with ERT. It is also believed to have the potential to prevent or slow the progression of symptoms like spinal abnormalities that cause loss of mobility over time. If approved, vosoritide would be the first oral therapy available for Morquio Syndrome patients.
Hope on the Horizon for Patients
The promising early results from the vosoritide clinical trial program have given hope to the Morquio Syndrome community who have long awaited more effective treatments. In a Phase II trial, biannual growth velocity increased significantly in children receiving vosoritide compared to placebo. No drug-related serious adverse effects occurred. An ongoing Phase III trial is evaluating the efficacy and safety of vosoritide over 24 months. Topline data is expected in late 2022, with potential regulatory filings projected for 2023 if results are positive. If approved, vosoritide could mean improved growth, mobility retention, and quality of life for Morquio Syndrome patients. It also offers the advantage of being the first oral therapy available to treat the root causes of the disease rather than just managing symptoms via intravenous administration as is done with ERT alone. This could help make treatment significantly more accessible and convenient for patients worldwide. The vosoritide clinical program signifies an important step towards empowering patients living with this debilitating condition.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
