Flexion Therapeutics, Inc. is a specialty pharmaceutical company. The Company is focused on the development and commercialization of therapies for the treatment of patients with musculoskeletal conditions, beginning with osteoarthritis (OA), a type of degenerative arthritis and post-operative pain. The Company's portfolio of product candidates addresses the OA pain treatment spectrum, from moderate to severe pain. The Company's lead product candidate, Zilretta (also known as FX006), is a late-stage, injectable, sustained-release, intra-articular (IA) steroid for patients with moderate to severe OA pain. The Company's other product candidates include FX007, a preclinical, small-molecule tropomyosin receptor kinase A (TrkA) receptor antagonist designed to address post-operative pain, and FX005, a sustained-release p38 mitogen-activated protein (MAP), kinase inhibitor for the treatment of end-stage OA patients. The Company has not generated any revenue.