Experimental SMA therapy is eligible for FDA rare pediatric diseases.

On August 13th Scholar Rock, a clinical biopharmaceutical company, announced that the FDA had awarded SRK-015 Rare Paediatric Disease Qualification (RPDD) for the treatment of spinal muscular dystrophy (SMA).
RPDD aims to promote the development of drugs and biologics for certain serious and life-threatening rare pediatric diseases and, more importantly, the company will be eligible for a priority review after the drug is approved for a new drug for this rare pediatric disease.
SMA is a rare and often fatal genetic disorder that affects one in every 10,000 babies.
the disease is caused by defects in the SMN1 gene, the protein produced by the SMN1 gene is important for the survival and function of lower motor neurons, which dominate the degeneration and loss of lower motor neurons in skeletal muscles leading to muscle atrophy.
past few years, the FDA has approved three drugs for SMA: Roche Evrysdi, YanJian Spinraza and Novarma Zolgensma.
the companies have been competing for market share, with Spinraza generating $2.1 billion in sales in 2019 and Zolgensma generating $361 million in revenue in its first year on the market.
Scholar Rock believes that while there has been significant progress in therapeutic research to reduce the loss of motor neurons, treatments for direct muscular dystrophy are still needed, which will help improve muscle strength and motor function.
SRK-015 has the potential to become the first muscle-directed treatment for muscular dystrophy in SMA patients, available as a monotherapy or in combination with any approved SMN-adjusted therapy.
SRK-015 is a selective local muscle-building inhibitor activation inhibitor.
myostatin is a member of the growth factor TGF beta super family, expressed mainly by skeletal muscle cells, to inhibit muscle growth.
in the body, it works with other growth factors and hormones to maintain proper muscle mass.
the absence of genes is associated with increased muscle mass and strength in many animals.
based on existing studies of muscle growth and muscle formation mechanisms, SRK-015 inhibits the activation of muscle-building inhibitors and may promote a clinical increase in muscle strength.
the company is developing SRK-015 as a therapy to improve muscle strength and motor function in SMA patients.
the FDA and the European Commission have both awarded the drug the SMA's orphan drug title.
previously, phase I clinical trials completed in adult healthy volunteers had observed good tolerance of SRK-015, with a maximum assessed dose of 30 mg/kg and no dose-limiting toxicity.
pharmacodynamic data show that SRK-015 successfully activates potential myogen inhibitors in a robust and long-lasting manner, providing a mechanism for a unique treatment for this unique form of targeted muscle-building inhibitors.
SRK-015 also showed a good pharmacodynamic curve with a serum half-life of 23-33 days.
positive interim results support SRK-015's entry into Phase 2 proof-of-concept clinical trials.
Scholar Rock also makes it clear that SRK-015 is not a traditional method of blocking activated mature muscle-producing inhibitors or myogen-producing inhibitor subjects, but by targeting potential forms, so the drug avoids blocking the activity of other closely related members of the TGF beta super family, which can lead to adverse side effects.
safety and effectiveity of patients with SRK-015 for type 2 and type 3 SMA are being studied in Phase 2 concept-validated clinical trial TOPAZ.
the trial included 58 patients between the ages of 2 and 21 in three different groups from the United States and Europe.
all patients receive SRK-015 treatment every four weeks, 100,015 treatments, or combination therapy with approved SMN-adjusted regulatory factors over a 12-month treatment period.
the main endpoints will measure the patient's motor function by clinically significant outcome indicators that have been validated in SMA treatment, such as the in activity SMA's Hammersmith functional exercise scale and the improved Hammersmith scale.
Rock plans to report TOPAZ's six-month interim efficacy and safety data in the fourth quarter of 2020 and the top-line data for the 12-month treatment period in the first half of 2021.
It is understood that Scholar Rock specializes in the development of innovative drugs for serious diseases where protein growth factor signaling plays a fundamental role, with a product line for neuromuscular diseases, cancer, fibrosis and anemia, and SRK-015 is its leading research candidate.
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