A new tumor necrosis factor alpha (TNF-α) blocker with a unique once-monthly dosing schedule has been approved, but despite its advantages, few believe it will shake up the market. Simponi (golimumab) won approval from the US Food and Drug Administration for three rheumatology indications—rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis—in April, and from Health Canada earlier that month. Simponi, a fully human anti-TNF-α monoclonal antibody produced by Johnson & Johnson's (J&J) subsidiary Centocor Ortho Biotech of Horsham, Pennsylvania, and Schering-Plough of Kenilworth, New Jersey, must compete in the already crowded rheumatology space, which includes J&J's own blockbuster Remicade (infliximab). Market watchers, however, believe it is unlikely Simponi will displace best-selling counterparts Enbrel (etanercept), Humira (adalimumab) and Remicade. Janice M. Reichert, a senior research fellow at Tufts Center for the Study of Drug Development in Boston, who collects data on emerging drugs in the industry says: “Remicade has an established market and it is difficult to push something out of [that] position.” If a patient is responding well to conventional treatment, Reichert notes, the physician will be reluctant to switch to a new therapy, especially when a clear competitive advantage is lacking. Simponi's once-monthly dosing schedule, less frequent than that of other TNF-α blockers. could provide that advantage.