Novartis has received the US Food and Drug Administration (FDA) Orphan Drug Designation for branaplam (LMI070) in treating Huntington’s disease (HD).

The US regulator grants Orphan Drug Designation as a special status to a drug with potential to treat a rare disease or condition. The status supports sustained development of medicines for the severe diseases, by offering benefits to pharma firms.

Huntington’s disease (HD) is a rare, inherited neurodegenerative disease, characterised by progressive worsening in motor, cognitive and psychiatric symptoms in people aged between 30 and 50 years, which worsen over a period of 15 to 20-years.

Current treatment options for HD are limited to symptomatic treatments and there are no approved disease modifying therapies that delay disease onset or slow progression of the disease.

Branaplam is an oral once-weekly small molecule RNA splicing modulator

All humans have the huntingtin (HTT) gene, but only those with a mutated gene will develop the disease, which leads to a progressive disability and death.

Decline in huntingtin mRNA is expected to reduce the huntingtin protein levels, which is the underlying cause of HD.

Branaplam is a small molecule RNA splicing modulator, orally administered once-weekly. The drug is currently being studied for the treatment of spinal muscular atrophy (SMA), since more than 5 years.

SMA is a rare, progressive genetic disease, characterised by loss of motor neurons responsible for muscle function.

The Swiss drugmaker said that during the study of branaplam in SMA, branaplam was effective in reducing huntingtin messenger RNA (mRNA) in SMA patients

Also, the drug has reduced the mutant huntingtin protein levels in preclinical models.

Based on study results, the company intends to begin a development programme for branaplam to determine the potential to treat people living with the HD.

Branaplam is dosed once weekly for the treatment of SMA and the same dosing regimen may also be a possibility for HD. Novartis plans to start the Phase 2b trial for branaplam in HD patients in 2021.