A tiny but growing population of individuals with complicatedillnesses and special treatment needs are accounting for anincreasingly significant amount of the nation’s overall prescription drug costs, according to a reportfrom ExpressScripts, “Super Spending: U.S. Trends in High-CostMedication Use.”

“We live in a fortunate time when science has delivered amazingtherapies and made it possible for people with complex, chronicdiseases to live a little more normal life,” Glen Stettin, M.D.,senior vice president, clinical, research and new solutions atExpress Scripts, writes in the report’s foreword note.

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“Over the past five years, 118 specialty treatments have come to market forthese conditions, and the medication pipeline is rich, with about25 new specialty drugs expected to receive approval each year forthe next five years,” Stettin writes. “We’re also entering an erawhere customized gene therapies offer hope for a cure for seriouscancers and other rare, fatal diseases. Because these therapiestarget small patient populations, are administered once anddemonstrate premium outcomes, they will command premiumprices.”

The St. Louis-based pharmacy benefit manager analyzedprescription drug use data for 134,008 members of plans it manages,and found that about 3 out of 1,000 people met or exceeded $50,000in prescription drug costs – a 35 percent increase from 2014 – andaccounted for more than 20 percent of total prescription drugcosts.

Several years ago, compounded medications and new hepatitis Ctherapies drove much of the spending for this group, butExpressScripts’ authors write “through our leadership in reducingdrug costs,” payers in 2016 spent less on the hepatitis Ctherapies, and opted for safer and lower-cost over-the-counteralternatives to compounded medications.

Now, the top cost drivers are treatments for cancer, multiplesclerosis, inflammatory conditions, cystic fibrosis and othercomplex and rare diseases, according to the report. In 2016, morethan a quarter of the prescription drug costs for people with$50,000+ in prescription drug costs were for cancer drugs.

Many of the individuals were in Medicare plans – in fact, thispopulation was four times as common in Medicare plans than inemployer-sponsored, Medicaid or exchange plans, with eight outof every 1,000 Medicare beneficiaries reaching $50,000 inprescription drug costs in 2016.

For all people with $50,000 or more in 2016 prescription drugcosts, the majority of costs were borne by the employer, healthplan or government entity. Employers and commercial health planspaid 97.7 percent of the prescription drug costs, similar to theportion paid by Medicare and exchange plans. Medicaid plans paid99.9 percent.

On average, people with $50,000 or more in prescription drugcosts paid $2,156.46 annually out of pocket, compared to$228.62 for those with prescription drug costs of $49,999 and less.For all patients with prescription drug costs over $50,000, 97.6percent of costs are paid for by plans.

“While there’s more to do to make costly treatments moreaffordable, we’re working with payers to pull all availablelevers for managing spend in other areas to create headroomfor covering patients who need more costly therapies,” thereport’s authors write. “This includes effectively managingutilization, leveraging competition within formularies, providinggreater care and clinical support, and embracing new strategies forreimbursement.”

Despite the increase in the size of this population, employersand Medicare plans held the increase in overall drug spendingto just 3.8 percent and 4.1 percent, respectively, in 2016,demonstrating the effectiveness of private-sector solutions tomake medicine more accessible and affordable.

Plans covered nearly 97.6 percent of the costs for people withprescription drug costs of $50,000 or more in 2016, paying anaverage of $89,308 per person. Payers also kept members’total out-of-pocket cost share relatively flat. In2016, people with $50,000 or more in prescription drug costshad average annual out-of-pocket costs of $2,156 (2.4%),excluding patient assistance from manufacturers orfoundations.