People with diabetes who rely on insulin have seen the cost of that drug triple in just a decade, according to a study from the University of Michigan. The increase in insulin costs was so large that, since 2010, the per-person spending on insulin has been higher than per-person spending on all other diabetes drugs combined.
Published in the Journal of the American Medical Association, the findings estimate what patients and their insurance plans paid from 2002 to 2013 for all antihyperglycemic medications.
“In the United States, the more than threefold increase in the cost of insulin over the past decade is alarming. It is a burden to both patients and payers and may deny some people access to a lifesaving therapy,” said co-author William H. Herman, MD, MPH. “Although the newer, more-expensive insulin analogs appear to have incremental benefits compared to older, less-expensive insulin preparations, their premium price requires us to ask whether they are really necessary, and if so, for whom?”
During the period studied, the total cost of insulin more than tripled, from $231 a year to $736 a year for each patient, in 2013 dollars. At the same time, the cost per milliliter of insulin nearly tripled, from $4.34 to $12.92. Further, the average annual usage increased from 171 mL to 206 mL as prescribed doses went up.
Meanwhile, the per-person spending on all other blood sugar medications was $502 in 2013, down from about $600 in 2002, according to the authors. The cost of these medications combined dropped over the first nine years, bottomed out in 2011, and has risen slightly since then.
The cost of metformin, which is available as a generic drug, plummeted from $1.24 per tablet in 2002 to just 31 cents in 2013. Even the newer class of drugs known as dipeptidyl peptidase 4 (DPP-4) inhibitors only got 34% more expensive since they hit the market in 2006.
The researchers analyzed data from nearly 28,000 people who received treatment for diabetes during the 11-year period, a time when the diabetes rate was rising steadily. The subjects’ average age was approximately 60 years.
About one in four of the participants used insulin to control their blood sugar, and two-thirds were taking an oral medication. In the latter part of the study period, a small percentage began taking new injectable drugs designed to complement oral drug use.
The researchers could not separate users of synthetic human insulin, the least-expensive form currently available, from those who used the more-recent analog forms. The authors also didn’t have data on the amounts spent by insulin users for the needles and other devices used to inject insulin, except when that cost was included in drug costs, such as for prefilled insulin pens.