(Reuters Health) - Annual costs of disease modifying treatments for multiple sclerosis more than quadrupled from 2006 to 2016 as several new, costly medicines entered the market, a U.S. study suggests.

Before 2009, only four drugs were available to reduce symptoms and slow the progression of multiple sclerosIs (MS), a disabling autoimmune disease that damages the central nervous system and can lead to fatigue, pain, vision loss and impaired coordination and motor skills. Since 2009, seven new drugs have entered the U.S. market.

To assess shifts in costs after the debut of so many new medicines, researchers examined the annual cost of treatment for Medicare Part D drug plans based on doses of each injected medicine recommended by the U.S. Food and Drug Administration.

Over the decade-long study period, Medicare spending on MS drugs surged 10.2-fold, from an average of $7,794 to $79,411 a year, researchers report in JAMA Neurology.

Patients’ out-of-pocket spending soared 7.2-fold from $372 to $2,673 a year on average.

“Such an increase in patients’ out-of-pocket spending is particularly worrisome because it may jeopardize patient access to medications,” said Alvaro San-Juan-Rodriguez, lead author of the study and a researcher at the University of Pittsburgh School of Pharmacy

“We hope that our work will serve as a call to action to address the pressing issue of rising drug prices; thus, ensuring the affordability and access to specialty medications and the best possible outcomes for patients,” San-Juan-Rodriguez said by email.

The study wasn’t a controlled experiment designed to prove whether or how price hikes might have directly impacted patients’ access to medications, and the study also didn’t look at any negative health outcomes that might be associated with stopping or reducing medication use due to costs.

Another limitation of the study is that researchers lacked data on rebates that drugmakers may pay to Medicare, which would reduce the total amount of spending on these drugs.

Another drawback is that the study only looked at self-administered drugs that patients can get at the pharmacy and inject themselves at home. The study didn’t look at medicines that are only available in doctors’ offices such as Tysabri, which is commonly prescribed for MS, or medicines that are available by infusion and covered by traditional Medicare, not by Medicare drug plans.

Before 2009, four self-administered disease modifying MS drugs were available in the U.S.: Copaxone, Avonex, Rebif, and Betaseron. Since then, seven more have hit the market: Extavia, Gilenya, Aubagio, Tecfidera, Copaxone (at a higher dose), Plegridy, and Glatopa.

Older drugs and generics aren’t necessarily cheaper for Medicare or for patients than newer brand-name drugs, making it even harder for patients to figure out how to best lower their out-of-pocket spending on medicine, San-Juan-Rodriguez said.

“Although generics are generally cheaper than brand names drugs, the use of generic specialty medications does not lead to lead to savings for Medicare Part D beneficiaries,” San-Juan-Rodriguez said. “On the contrary, due to incentive misalignments created by the Medicare Part D benefit design, beneficiaries using generic drugs such as Glatopa (generic version of Copaxone) may pay more than those using the branded drug.”

And price hikes can also mean access problems for patients who may find their insurance stops covering certain drugs or raises the share of the bill passed to patients as out-of-pocket fees,” said Dr. Dennis Bourdette, chair of neurology at the school of medicine at Oregon Health & Science University and author of an editorial accompanying the study.

“Because of the high cost of these medications, insurance carriers seek to control expenses by limiting access to these drugs,” Bourdette said by email. “Patients should look carefully when choosing insurance carriers at co-pays and what limitations to access the insurance company has.”

SOURCE: bit.ly/341PiPL JAMA Neurology, online August 26, 2019.