OBJECTIVES

: Diabetes mellitus is one of the most prevalent and costly chronic diseases in the United States (US). The high cost of insulin presents a financial challenge to patients and health care payers. This study assessed trends in injectable 100u insulin prices in the US in the period of 1980-January 15, 2019.

METHODS

Regulatory data for injectable 100u insulin marketed in the US during the study period derived from FDA databases; and average wholesale prices (AWP) from the RedBook (IBM Micromedex). Prices were converted to 2018 US$using the consumer price index (CPI) (Bureau of Labor Statistics). The compound annual growth rate (CAGR) for the CPI-adjusted AWP 30-days supply (DDD) was calculated from first AWP effective date to January 15, 2019 or the drug discontinuation date.

RESULTS

There were 35 injectable 100u insulin, including 11 animal and 11 human source insulin, and 13 analogue insulin marketed in the US anytime during the period 1980- January 15, 2019. All animal source insulin was discontinued as of November 2000. CPI-adjusted median prices of human insulin at market entry increased from $180.11 in the 1980s to $233.20 in the 2000s. CPI-adjusted median prices of analog insulin at market entry increased from $359.58 in the 1990s, to $508.56 in the 2000s and $1,982.58 in the period 2010-2018. The median CPI-adjusted CARG for human insulin was 3.2% for insulin first marketed in the 1980s and 6.6% for those marketed in the 1990s. The median CPI-adjusted CARG for analog insulin was 7.5% for insulin first marketed in the 1990s, and 8.5% in the 1990s and 0.6% in the period 2010-2018.

CONCLUSIONS

: Prices of human insulin and analogues at market entry increased during the study period. CPI-adjusted prices of marketed insulin products also increased significantly after market entry.