Researchers at Brigham and Womenâ€™s Hospital set out to evaluate the effects of switching insulins in those with type 2 diabetes.
The US drug market has seen a significant increase in the price of insulin over the past 2 decades. Although the price has increased for all forms of insulin, newer, “analogue” insulin medications, such as glargine and lispro, can cost 2 to 10 times more than less expensive human insulin, such as human neutral protamine Hagedorn (NPH). In fact, Medicare’s outpatient prescription drug program (Part D) spent more than $4 billion on just 1 long-acting analogue insulin in 2016.1
In 2015, CareMore Health piloted an intervention to switch members from analogue insulin to less expensive human insulin. They partnered with investigators from Brigham and Women’s Hospital and Harvard Medical School to evaluate the implementation of Caremore’s health plan-based intervention of switching insulin types.
Beginning in 2015, the researchers conducted a retrospective cohort study of the data from 14,635 older adults with type 2 diabetes who filled 221,866 insulin prescriptions between 2014 and 2016, gathered from the CareMore Medicare Advantage prescription drug plan operating in Arizona, California, Nevada, and Virginia.
Levels of HbA1c
Before the intervention, the mean HbA1c levels were 8.46% (an HbA1c of 7% to 8% is recommended by the American College of Physicians for most adults with type 2 diabetes) decreased at a rate of −0.02% per month before the intervention. The results of the study found that the switch was associated with only a small, population-level increase—0.14%—in hemoglobin A1c (HbA1c), a value that falls within expected biological variation.
"The change that we found is so small that I do not believe this is clinically meaningful or relevant," said corresponding author Jing Luo, MD, MPH. "Importantly, we also found that this switch was not associated with serious hypoglycemic or hyperglycemic events and [also] improved economic outcomes for patients and across the health system."
At the start of the intervention, 89% of filled insulin prescriptions were for analogue insulin products. By December 2016, 70% of insulin prescriptions were for human insulin products.
Part D Coverage Gap
In 2014, 20.6% of participants reached the Part D coverage gap, yet by 2016 this percent had dropped to 11.1%.
The results of this study suggest that human insulins may become a viable option for those who may not be able to afford more expensive options such as analogue insulins, according to the study authors.
"The results of the current study add to a growing body of literature suggesting that human insulins may result in similar clinical outcomes compared with insulin analogues for many patients with type 2 diabetes," Luo said. "Our study provides real-world evidence from clinical practice that should reassure patients, providers, and payors that it may be possible to switch to an older less expensive insulin to bring down costs while preserving quality of care."