OBJECTIVES:  The objective of this study was to evaluate trends in manufacturer-listed prices of therapeutic biologics approved by the FDA for chronic use and marketed in the US during the period 1986–2015. METHODS:  Regulatory information for therapeutic biologics was extracted from the FDA website. The FDA recommended adult defined daily dose (DDD) was collected from the first FDA-approved label of each biologic. The average wholesale price (AWP) history was collected from the RedBook. Prices were adjusted to the first semester of 2016 using the consumer price indec (CPI) US city average, all items. Descriptive statistics and Wilcoxon rank sum tests and t-tests were performed. The significance level was set at 0.05. RESULTS:  The analytical sample included 58 biologics (representing 51.3% of all FDA- approved therapeutic biologics during the period 1986-2015). The median market entry inflation-adjusted AWP per DDD was $113.10 (n=2, interquartile range [IQR]=47.70) in the 1980s, $64.80 (n=7, IQR=99.70) in the 1990s, $105.90 (n=24, IQR=294.60) in the 2000s, and $213.00 (n=25, IQR=504.10) during the period 2010-2015. The median inflation-adjusted AWP per DDD for therapeutic biologics for chronic use at market entry was higher for FDA-priority rewiew ($389.20, n=34, IQR=636.00) than for standard review ($88.50, n=24, IQR=105.30; p<0.05). CONCLUSIONS: The FDA approved an increasing number of therapeutic biologics for chronic use during the period 1986-2015. Median AWP prices at market entry increased over time, and the increase in the prices of therapeutic biologics at market entry exceeded the inflation rate.