WALTHAM, Mass.--(BUSINESS WIRE)--Repligen Corporation (NASDAQ: RGEN) announced today that the Company President and Chief Executive Officer, Walter C. Herlihy, Ph.D., will host a conference call and webcast on April 21, at 10:00 a.m. EDT, to discuss preliminary fiscal year 2011 financial results and provide financial guidance and development goals for fiscal year 2012.