The impact of orphan drugs on rare disease treatment costs
One of the defining trends of pharmacy in recent years has been the availability of new drugs to treat rare conditions.
Many of these medicines were developed due to the incentives created by the 1983 Orphan Drug Act, which grants seven-year market exclusivity for drugs treating rare conditions. While orphan drugs represent a fantastic improvement for the people who use them, they are costly – with the average annual cost per member now at approximately $147,000.1
In this article we will explore the orphan drug market by examining neuromyelitis optica spectrum disorder (NMOSD), an autoimmune disease that primarily affects the optic nerves and spinal cord. Also known as Devic’s disease, NMOSD is rare and thought to impact approximately 1 in 100,000 people in the U.S.2
In the period of just over a year, the U.S. Food and Drug Administration (FDA) approved three interventions for this rare and debilitating disease. All three treatments were awarded orphan drug designations.
Much like a related condition, multiple sclerosis, NMOSD features flare-ups, or clusters of attacks, followed by periods of remission. The attacks are caused by the immune system mistakenly attacking the body’s own cells in the central nervous system.3 These episodes can be severe and lead to irreversible effects, such as optic neuritis, which causes vision loss and ultimately blindness. NMOSD can also cause loss of bladder and bowel control and paralysis of the arms and legs.
Historically, the standard of care for NMOSD was to treat the acute attacks with corticosteroid drugs in order to prevent accumulating neurological damage. If this proves ineffective, a blood plasma transfusion can reduce the amount of harmful antibodies in the bloodstream. To reduce the risk of future attacks, treatment guidelines have supported the first-line use of off-label immunomodulators such as azathioprine, mycophenolate mofetil, and rituximab for over 10 years.