Specialty drug spending trends among Medicare and Medicare Advantage enrollees, 2007-11.

Specialty pharmaceuticals include most injectable and biologic agents used to treat complex conditions such as rheumatoid arthritis, multiple sclerosis, and cancer. We analyzed trends in specialty drug spending among Medicare beneficiaries ages sixty-five and older using 2007-11 pharmacy claims data from a 20 percent sample of Medicare beneficiaries. Annual specialty drug spending per beneficiary who used specialty drugs increased considerably during the study period, from $2,641 to $8,976. However, specialty drugs accounted for only 6.7 percent of total drug spending per beneficiary in 2007 and 9.1 percent in 2011. Moreover, in 2011 cost-sharing reductions under the Affordable Care Act significantly reduced specialty drug users' out-of-pocket burden, which decreased 26 percent from 2010. Oral cancer agents accounted for a significant proportion of the increase in specialty drug spending among the study population. This suggests that the migration of specialty drug coverage from Medicare's Part B medical benefit to the Part D pharmacy benefit because of new treatment options may play an important role in specialty pharmacy trends. This shift is likely to continue as pharmaceutical innovations enable more specialty therapeutics to be self-administered and to be covered under the pharmacy instead of the medical benefit.