TARRYTOWN, N.Y.--(BUSINESS WIRE)--April 19, 2006--Regeneron Pharmaceuticals, Inc. (Nasdaq:REGN - News) announced today that it has completed enrollment for a pivotal trial in its phase 3 program for the treatment of CIAS1-Associated Periodic Syndrome (CAPS), a spectrum of very rare genetic disorders. This orphan drug program is assessing the efficacy and safety of the Interleukin-1 (IL-1) Trap in adult patients with these autoinflammatory diseases. The efficacy phase of this trial is expected to be completed by the end of 2006.