Rare sclerosis unmasked: Insights into orphan drugs for amyotrophic lateral sclerosis

Orphan drugs are essential for the treatment of rare diseases, which impacts 3-6% of global population. These conditions are often overlooked by major pharmaceutical companies due to the limited commercial viability, leading to WHO (World Health Organisation) to term them as ‘neglected’. This article explores various types of rare sclerosis and focuses on Amyotrophic lateral sclerosis (ALS), its current treatment options and approved orphan drugs. Various types of rare sclerosis include Balo’s concentric sclerosis (BCS), Schilder’s disease, Tumefactive multiple sclerosis, multiple sclerosis (MS) and Amyotrophic lateral sclerosis (ALS). All these types affect central nervous system (CNS) with varying pathophysiology and symptoms. While no specific orphan drugs exist for these (Balo’s concentric sclerosis, Schilder’s disease, Tumefactive multiple sclerosis) types, symptoms are managed by corticosteroids, interferons and immunosuppressants. Multiple sclerosis (MS) has disease modifying therapies (DMT) available which includes Beta interferon and Glatiramer acetate. ALS is a progressive neurodegenerative disease that affects motor neurons. Its pathophysiology involves glutamate excitotoxicity, gene mutations, oxidative stress, and neuroinflammation. Current treatments include Riluzole and Edaravone; the combination of Sodium Phenylbutyrate and Taurursodiol was discontinued due to safety concerns. Novel approaches like small molecules, gene therapy, and stem cell treatments are under evaluation. Some drugs were granted Orphan designations for ALS, such as Riluzole (EXSERVAN), Edaravone (RADICSAVA), and Tofersen (QALSODY), while Lenzumestrocel is under clinical evaluation. Despite their small market share, orphan drugs are crucial for addressing rare diseases. Enhancing their identification, diagnosis, prevention, and treatment will result in improved healthcare outcomes for affected individuals.