This research service covers the United States market for ankylosing spondylitis pharmaceuticals market from 2009 to 2017, with 2011 as the base year. The focus of this research is on biologics and other treatments prescribed as add-on therapies; background standard of care therapies are not covered in this study. Included in the study are products on the market and products in development as well as patient and revenue forecasts. Market challenges, drivers, and restraints are identified and assessed. The market is segmented by classes of drug: tumor necrosis factor (TNF) inhibitors and non-TNF biologics.