Trends in Pricing and Generic Competition Within the Oral Antibiotic Drug Market in the United States.

BACKGROUND: In recent years, the price of many older generic drugs, including numerous antibiotics, has increased substantially. We sought to analyze recent price changes and extent of generic competition within a cohort of commonly prescribed off-patent oral antibiotics.

METHODS: We extracted oral antibiotics recommended for common outpatient conditions in the Infectious Diseases Society of America Practice Guidelines. We determined all US Food and Drug Administration-approved manufacturers for each formulation and strength in 2013 and 2016 and the yearly national average drug acquisition cost (NADAC) price between 2013 and 2016. Wilcoxon signed rank test was used to compare changes in drug prices and number of manufacturers from 2013 to 2016. Spearman correlation coefficient was used to assess the association between drug prices and number of manufacturers.

RESULTS: Twenty-two antibiotics (81 formulations and strengths) were analyzed. There was no change in the median NADAC price or the number of manufacturers between 2013 and 2016. However, 11 (14%) formulations increased in price by 90% or more, and 13 (16%) had 2 or fewer manufacturers during all 4 years. Antibiotic prices were negatively associated with the number of available manufacturers.

CONCLUSIONS: While prices and the number of manufacturers for common oral antibiotics were overall stable between 2013 and 2016, reduced manufacturer competition was associated with increased prices. A subset of antibiotics exhibited substantial price increases, and most, but not all, had limited manufacturer competition. Policy solutions are needed to ensure availability of low-cost, essential generic antibiotics.