OLE Trial Data Shows Arimoclomol Efficacy for NPC

In the past, arimoclomol has not always shown treatment promise. For example, the drug failed to meet primary or secondary endpoints in a clinical trial evaluating arimoclomol for patients with amyotrophic lateral sclerosis (ALS). That being said, new results from a 24-month (2 year) open-label extension (OLE) trial evaluating arimoclomol for Niemann-Pick disease type C (NPC) did show efficacy. In a news release from biopharmaceutical company CytRx Corporation (“CytRx”), the organization commented on the new data.

Arimoclomol

Previously, CytRx sold arimoclomol to biopharmaceutical company Orphazyme, who ran the OLE trial. During the trial, researchers examined the safety, efficacy, and tolerability of this investigational treatment for patients with NPC. While 24-month data is available, the researchers want to continue treatment up to 36 months. According to Orphazyme, arimoclomol is:

a first-in-class heat shock protein (HSP) amplifier:

  • A small molecule manufactured in a capsule formulation; designed to be swallowed whole, opened to allow contents to be mixed with soft foods/liquids or delivered through a nasal gastric tube or PEG
  • Designed to address neurodegenerative manifestations of disease

Heat shock proteins can play a variety of roles in regards to lysosomal function or rescuing defective or misfolded proteins. Additionally, arimoclomol is designed to cross the blood-brain barrier (BBB), making a more effective and targeted treatment. Thus far, the investigational therapy has received Fast Track, Breakthrough Therapy, Rare Pediatric Disease, and Orphan Drug designations within the United States; and Orphan Drug designation within the EU.

OLE Trial Results

Some of the study findings were presented during the Parseghian Scientific Conference. Findings included:

  • Arimoclomol is relatively safe and well-tolerated.
  • Following treatment, arimoclomol reduced NPC disease progression and sustained this response over an extended period of time. To measure this, researchers used the NPC Clinical Severity Scale.

According to CytRx CEO Steven A. Kriegsman, CytRx is happy with the therapeutic potential of arimoclomol. He also explains that the company looks forward to seeing what Orphazyme will do in terms of its therapeutic pipeline moving forward.

Niemann-Pick Disease

There are three types of Niemann-Pick disease, a group of rare and severe metabolic disorders. SMPD1 mutations cause forms A and B, while NPC1 or NPC2 mutations cause type C. In each case, the gene mutations affect a lipid called sphingomyelin. It is defective or deficient in Niemann-Pick disease types A and B, and the transporter protein is affected in type C. As a result, sphingomyelin builds up in lysosomes and causes health issues.

In Niemann-Pick disease type C (NPC), patients are unable to metabolize lipids and cholesterol, causing these to build up in the brain, liver, and spleen. Typically, symptoms appear between ages 4-10. However, symptoms may appear earlier or later than that. Unfortunately, NPC is often fatal before age 40. Symptoms include:

  • Enlarged spleen and liver
  • Jaundice (yellowing of the skin and eyes)
  • Inability to move eyes up and down
  • Appetite loss
  • Abdominal distention
  • Pain
  • Slurred speech
  • Difficulty swallowing
  • Enlarged bone marrow cavities
  • Thrombocytopenia (low platelet count)
  • Intellectual or learning delays
  • Failure to thrive
  • Cholestasis

Learn more about Niemann-Pick disease.