In the United States, Orphan Drug designation is granted to drugs or biologics intended to treat, diagnose, or prevent rare diseases. These are defined as conditions affecting under 200,000 Americans. As an incentive, drug developers also receive benefits through this designation, including tax credits, fee waivers, increased regulatory assistance, and 7 years of market exclusivity upon approval. According to Healio, Orphan Drug status was recently granted to Visomitin, a therapy for those with Leber hereditary optic neuropathy (LHON).

Visomitin

In a news release regarding the Orphan Drug status, Visomitin is described as:

a cardiolipin peroxidation inhibitor…designed to sustain and restore mitochondrial function and interrupt apoptosis in mitochondrial conditions like LHON. In DED Visomitin’s novel multimodal action targets inflammation, corneal/conjunctival damage, tear deficiency, and gland tissue regeneration.

Researchers have already evaluated Visomitin within a prior Phase 2a trial. During this trial, researchers found that Visomitin helped improve visual acuity in those with LHON. In fact, the study found that vision continued to improve over a period of many years, showing a durable and sustained response.

Moving forward, researchers hope to continue evaluating Visomitin for LHON in a clinical setting.

Leber Hereditary Optic Neuropathy (LHON)

Leber hereditary optic neuropathy (LHON) is an inherited form of vision loss and a mitochondrial disease. Genetic mutations in mitochondrial DNA cause LHON, meaning the mutated genes are passed down maternally. Often, this condition manifests as sudden, painless clouding or vision loss in one or both eyes, though the vision loss eventually affects both eyes. Males are 4-5x more likely to have LHON than females. Typically, symptoms appear in teenage years or young adulthood. In many cases, people often lose their vision before 40 years old. While vision loss, blurred vision, and loss of color perception are the most common symptoms, sometimes other symptoms appear. These less common symptoms include:

• Peripheral neuropathy
• Tremors
• Movement disorders
• Muscle weakness
• Cardiac conduction defects
• Poor coordination