Average Net Price for Insulin Glargine Declined After Basaglar Won FDA Approval

A research letter in JAMA Internal Medicine examined pricing changes in the insulin glargine market following the FDA approval and entry of Basaglar (insulin glargine injection; Eli Lilly) into the market.

The authors said their data suggest the approval was followed by a “substantial change in the trajectory of net prices” for insulin glargine products. After a steady increase in prices for Lantus, the only insulin glargine on the market from 2010 to 2014—the FDA approved Biocon Biologics’ Semglee insulin glargine on July 28—the average net price of all insulin glargine products decreased from 2015 to 2020.1

Basaglar, although it has the identical amino acid sequence to Biocon Biologics and is referred to as a biosimilar in the publication, was approved as a new drug, not a biosimilar. Until 2020, new versions of insulin products were approved in the United States via the Food, Drug, and Cosmetic Act section 505(b)(2) new drug application pathway. Starting later this year, biosimilar insulin products could be approved instead via the Public Health Service Act section 351(k) biologics license application pathway.2

Insulin glargine, a long-acting form of insulin, has been sold under the name Lantus by Sanofi since 2000. However, the patent on insulin glargine expired in February 2015, opening an opportunity for new insulin glargine products. Basaglar was approved by the FDA in December 2015 after a tentative approval in 2014, and it entered the market in December 2016.

The researchers noted that patent litigation delayed Basaglar’s market entry following its approval. Prior to the launch of Basaglar, Sanofi launched Toujeo, a higher-concentration insulin glargine product “that would not directly compete with Basaglar,” which the researchers reasoned was “a possible strategic move to maintain market share.”

The researchers studied 10 years of net price estimates and sales data from the SSR Health Drug Database, from Q1 of 2010 to the Q2 of 2020, for all 3 insulin glargine products.

Prior to 2015, Lantus was the only insulin glargine product on the market. According to the authors, its list price rose from $9.23 per 100 IU in Q1 of 2010 to $22.21 in Q3 of 2014, a 4.9% increase per quarter. They noted net prices were lower than list prices ($6.94 and $12.79, respectively) and rose more slowly (3.8% quarterly).

From 2015 to 2020, list prices “remained steady”; however, net prices of Lantus and the weighted average of all insulin glargine products declined. The price of Lantus declined by 5.2% per 100 IU per quarter compared with the average net price decline of 3.4% per quarter.

The researchers found that Lantus maintained the highest net sales of the 3 products throughout the 10-year period. However, by Q2 of 2020, Basaglar accounted for up 42.2% of sales compared with 46.2% for Lantus. Sanofi’s Toujeo, sold after Lantus lost exclusivity, “never gained greater than 15% market share,” according to the authors.

The researchers also conducted a single-group interrupted time series analysis to evaluate the trends in the weighted average net price of insulin glargine before and after Q4 of 2014, the approximate time of tentative approval of Basaglar. Their model estimated that prior to Basaglar’s approval, the net price of 100 IU of insulin glargine increased an average $0.36 per quarter, followed by a downward trend after approval of approximately $0.67 per quarter.

The investigators identified their focus on net prices rather than list prices, evaluating total sales, and the 10-year span of the data as strengths of their research. They said these factors allowed them to avoid methodological challenges frequently encountered in studies on the entry of a biosimilar into a biologic market, such as “failing to account for manufacturer-provided rebates, examining only a segment of US payers, and focusing on short-term changes.”

Future research, they said, could examine the association of market entry of new insulin biosimilars on the prices of both direct and nondirect competitors, and “the outcomes of decreasing net prices on patient out-of-pocket costs should be further investigated.”

References

1. Levy J, Chowdhury ZM, Socal MP, Trujillo AJ. Changes associated with the entry of a biosimilar in the insulin glargine market. JAMA Intern Med. Published online June 28, 2021. doi:10.1001/jamainternmed.2021.2769

2. Kim AP, Bindler RJ. The future of biosimilar insulins. Diabetes Spectr. 2016;29(3):161-166. doi:10.2337/diaspect.29.3.161