The cost of multiple sclerosis drugs in the US and the pharmaceutical industry: Too big to fail?

Abstract

Objective: To examine the pricing trajectories in the United States of disease-modifying therapies (DMT) for multiple sclerosis (MS) over the last 20 years and assess the influences on rising prices.

Methods: We estimated the trend in annual drug costs for 9 DMTs using published drug pricing data from 1993 to 2013. We compared changes in DMT costs to general and prescription drug inflation during the same period. We also compared the cost trajectories for first-generation MS DMTs interferon (IFN)-β-1b, IFN-β-1a IM, and glatiramer acetate with contemporaneously approved biologic tumor necrosis factor (TNF) inhibitors.

Results: First-generation DMTs, originally costing $8,000 to $11,000, now cost about $60,000 per year. Costs for these agents have increased annually at rates 5 to 7 times higher than prescription drug inflation. Newer DMTs commonly entered the market with a cost 25%-60% higher than existing DMTs. Significant increases in the cost trajectory of the first-generation DMTs occurred following the Food and Drug Administration approvals of IFN-β-1a SC (2002) and natalizumab (reintroduced 2006) and remained high following introduction of fingolimod (2010). Similar changes did not occur with TNF inhibitor biologics during these time intervals. DMT costs in the United States currently are 2 to 3 times higher than in other comparable countries.

Conclusions: MS DMT costs have accelerated at rates well beyond inflation and substantially above rates observed for drugs in a similar biologic class. There is an urgent need for clinicians, payers, and manufacturers in the United States to confront the soaring costs of DMTs.

Figure 1. Estimated annual costs of multiple sclerosis disease-modifying therapies in the United States from 1993 to 2013

Annual costs estimated from average wholesale prices (AWP), or wholesale acquisition costs if AWP not reported, and discounted 12%. IFN = interferon.

Figure 2. Segmented time series of median annual cost in the United States for first-generation multiple sclerosis disease-modifying therapies relative to tumor necrosis factor inhibitors

Disease-modifying therapies (DMTs) are interferon (IFN)–β-1b, IFN-β-1a IM, and glatiramer acetate and tumor necrosis factor (TNF) inhibitors are etanercept and adalimumab. Trends are % change in median annual cost per quarter. With the exception of the first (baseline) period, p values reflect changes in trend from one period to the next. Complete model results are reported in appendix e-1.