Biosimilar Semglee Could Spell Massive Changes for Net Cost of Insulin

The FDA’s approval of the insulin glargine biosimilar Semglee (insulin glargine-yfgn; Viatris) could potentially result in a considerable decrease in expenses for patients with diabetes who are dependent on insulin. Projecting how this approval could affect the cost of care for patients with diabetes requires an understanding of the current price for insulin in the United States, the mechanics causing it to rise, and what Semglee’s approval as an interchangeable biosimilar means for pharmacists and patients.

Insulin Prices Continue to Skyrocket

Prices for insulin have been rising in the United States at an unprecedented rate, nearly tripling between 2002 and 2013 and increasing by 15% to 17% per year between 2012 and 2016.¹ Average gross spending per person on insulin for patients with type 1 diabetes (T1DM) increased by $2841 between 2012 and 2016, and the percentage of those patients’ total health care spending for insulin alone rose from 23% to 31% across that same period.² For comparison, between 2006 and 2013, out-of-pocket costs per insulin user among Medicare Part D users increased by 10% per year, while overall inflation during the same time period was 2.2%, medical care service costs increased by 3.8%, and spending for all prescription drugs increased by an average of 2.8%.¹

High Prices by Design, Not Necessity

There is a growing gulf between the net price of insulin and its list price, with the majority of the responsibility belonging to the rebates and discounts negotiated between various stakeholders in the insulin supply chain. Manufacturers negotiate with pharmacy benefit managers (PBMs) to have their medications placed on a lower cost-sharing tier or to avoid constraints on utilization on the PBM’s client formulary, offering discounts on the list price in exchange. These rebates have come to represent nearly 50% of the net cost of insulin.¹

Although the majority of the rebate is paid to the insurance company, these rebates have also become a major source of revenue for PBMs.³ For instances in which the PBM’s clinical experts determine that one type of medication is necessary on a given formulary tier but there is no clinical preference for a single brand or formulation over another, preferential formulary tiering can be offered to manufacturers in exchange for better rebates.¹ Although manufacturers have control over their list price, higher insulin net prices result in higher rebates, which result in higher profits for the PBM and, by extension, a greater likelihood that the PBM will place that manufacturer’s insulin on a preferential tier.³

In their analysis of the current mechanics of insulin pricing, the Insulin Access and Affordability Working Group consistently encountered a “lack of transparency” throughout the insulin supply chain. Discounts negotiated between PBMs and manufacturers, as well as between PBMs and pharmacies, are, in the vast majority of cases, confidential, making it almost impossible to determine which stakeholders profit and by how much.¹

The ultimate result of this opaque negotiation is a higher list price for insulin and higher rebates paid between stakeholders, benefitting every member of the supply chain aside from the patient.³

Interchangeable Biosimilars, Semglee, and the Impact on Insulin Prices

A biosimilar is a biologic medication that is highly similar to an existing FDA-approved biologic product, known as the reference product, and must have demonstrated similar efficacy and safety. Biosimilars are intended to produce the same clinical effect as a reference product but at a lower cost, similar to generic drugs.⁴

Interchangeability is a regulatory designation indicating that the biosimilar is expected to produce the same clinical result as the reference product in any given patient. This is achieved through the submission of additional data to the FDA, often from switching studies, in which patients are switched between the reference product and the biosimilar multiple times to determine whether there is any effect. Practically, this allows pharmacists to substitute a biosimilar for the reference product without needing to consult the prescribing physician.⁴

“The FDA’s decision has created an overwhelmingly affordable long-acting insulin option for patients,” said David Steinberg, PharmD, director of pharmacy insights at Scripta Insights. “Pharmacists have always been educating patients about generic equivalents, their efficacy, and most importantly, their cost savings. Semglee costs roughly one-third of the price with the same safety and efficacy. Although every person reacts to medicine differently based on their DNA makeup, Semglee has proven to help lower blood sugar levels similarly to Lantus and Baslagar.”

Semglee is the first insulin biosimilar to receive FDA approval, and it’s difficult to be certain just how much it will reduce the net cost of insulin for patients. Early projections, however, are incredibly optimistic. Modeling the cost of a competitive biosimilar for insulin glargine in 2018, investigators determined that such a biosimilar could be sold at a profit for $5.32-$7.38 per 10 ml, which would be a 91.4%-93.8% decrease from their listed price for insulin glargine of $85.67 per 10 ml in the United States. However, this figure is based on a large number of assumptions and does not account for mark-ups added throughout the supply chain between manufacturing and the medication reaching the patient.⁵

“As always, it depends on the PBM and the insurer,” Steinberg said. “Most PBMs have hardened relationships with traditional manufacturers such as Eli Lilly, Novo Nordisk, and Sanofi. These relationships provide preferential treatment to formulary placement and sometimes exclusivity. As plan sponsors and patients begin to request Semglee as a preferred option for their patients, it will land on higher tiers and lower out-of-pocket co-pays.”

Despite this uncertainty, there is still plenty of reason to be optimistic about the impact of Semglee on insulin pricing. Steinberg remains hopeful that the introduction of Semglee will improve the accessibility and affordability of insulin for all patients.

“Uninsured patients may also pay less or nothing,” Steinberg said. “With the FDA’s new classification, Semglee will now be classified like a generic, which lowers the cost. Mylan, the manufacturer of Semglee, also offers patient assistance programs that could lower the cost to $0 for a 30-day supply for commercially insured patients. People without prescription insurance coverage may be able to get Semglee for free.”

Looking to the Future

With such a positive impact anticipated for Semglee, there is substantial cause for excitement about the future of insulin pricing and accessibility. Additionally, insulin glargine is not the only insulin product likely to see biosimilar competition in the near future. According to Steinberg, Biocon Biologics, the maker of Semglee, has submitted an application to the FDA for a biosimilar form of insulin aspart (NovoLog).

“Whereas glargine is a ‘long-acting’ insulin, aspart takes effect in the body with rapidity and is considered ‘short-acting,’” Steinberg said. “When the announcement was made by Biocon, Walmart announced (and is now selling) rapid-acting insulins made by drug manufacturer Novo Nordisk, for cash prices of $73 per vial and $86 for a box of five pre-filled syringes. This is good news for patients and brings hope that additional competition can spur innovation.”

REFERENCES

1. Cefalu WT, Dawes DE, Gavlak G, et al. Insulin Access and Affordability Working Group. Insulin Access and Affordability Working Group: conclusions and recommendations. Diabetes Care. 2018 Jun;41(6):1299-1311. doi: 10.2337/dci18-0019 Erratum in: Diabetes Care. 2018 Aug;41(8):1831. PMID: 29739814
2. Biniek J, Johnson W. Spending on individuals with type 1 diabetes and the role of rapidly increasing insulin prices. Health Cost Institute; January 21, 2019. Accessed August 2, 2021. https://healthcostinstitute.org/diabetes-and-insulin/spending-on-individuals-with-type-1-diabetes-and-the-role-of-rapidly-increasing-insulin-prices
3. Rajkumar S. The high cost of insulin in the United States: an urgent call to action. Mayo Clin Proc. January 2020;95(1):22-28. doi: 10.1016/j.mayocp.2019.11.013
4. Five key things pharmacists need to know as insulin biosimilars come to market. Pharmacy Times; July 29, 2021. Accessed August 2, 2021. https://www.pharmacytimes.com/view/five-key-things-pharmacists-need-to-know-as-insulin-biosimilars-come-to-market
5. Gotham D, Barber MJ, Hill A. Production costs and potential prices for biosimilars of human insulin and insulin analogues. BMJ Global Health. 2018;3:e000850.