Expenditure, Utilization, and Cost of Specialty Drugs for Multiple Sclerosis in the US Medicaid Population, 2008-2018

Multiple sclerosis (MS) is a rare, long-standing, and disabling disease that affects the central nervous system and causes several clinical manifestations. As a result, this disease is associated with a high societal economic burden.

To analyze the trends in drug expenditure, utilization, and cost of specialty drugs for the treatment of patients with MS in the US Medicaid program.

In this retrospective drug utilization research analysis, we obtained prescription data and reimbursement of disease-modifying therapies for MS from the Centers for Medicare & Medicaid Services Medicaid State Drug Utilization Data between January 2008 and December 2018. The specialty drugs considered in our analysis included dimethyl fumarate, fingolimod, teriflunomide, cladribine, siponimod, alemtuzumab, natalizumab, ocrelizumab, daclizumab, glatiramer acetate, peginterferon beta-1a, interferon beta-1a, and interferon beta-1b. The annual trends of the number of prescriptions, reimbursement expenditures, and costs were calculated. The average reimbursement per prescription was calculated as an estimate of the drug cost.

The annual MS drug utilization increased from 85,209 prescriptions in 2008 to 223,604 in 2016, and then decreased to 194,877 in 2018. The annual reimbursement surged by 633% in the 10-year study period between 2008 and 2018, from almost $172 million in 2008 to more than $1.4 billion in 2017, and then to approximately $1.26 billion in 2018. The cost per prescription increased over time for most MS brand-name drugs (eg, from $2033 in 2008 to $5114 in 2018 for natalizumab, and from $19,138 in 2016 to $23,588 in 2018 for alemtuzumab). In 2008, self-injectable drugs dominated the market. In recent years, a shift has occurred in the utilization and reimbursement of MS drugs, with oral medications becoming predominant.

The study findings indicate intermarket and interbrand competition among the MS specialty drugs. The growing utilization and spending trends for specialty MS medications are significant and sizable in the US Medicaid programs. Medicaid cost-containment strategy is warranted to control the economic burden of state budgets across the country.