On February 9, 2016, the Food and Drug Administration Arthritis Advisory Committee recommended by a vote of 21 to 3, that the biosimilar to infliximab, CT-P13, be approved for rheumatoid arthritis and ankylosing spondylitis and, by extrapolation, for all the indications for which infliximab is currently approved, including adult and pediatric ulcerative colitis and Crohn's disease. On April 5, 2016, the Food and Drug Administration concurred with this recommendation and approved CT-P13 (Inflectra; Pfizer Inc.) for all diseases for which infliximab had previously been approved, including adult and pediatric moderate to severe ulcerative colitis and pediatric and adult moderate to severe and fistulizing Crohn's disease. This was despite the absence of any randomized controlled trials studying the infliximab biosimilar in any inflammatory bowel disease. This highly controversial approach has been criticized by various rheumatology and gastroenterology professional societies around the world. This review will cover the stepwise approach to biosimilar development, issues of extrapolation and interchangeability, and conclude with a discussion of the regulatory, intellectual property issues, and financial implications, which will all intersect in the decision and ability to prescribe a biosimilar or reference anti-tumor necrosis factor drug.