Dave Summa Joins Acumen as President and CEO

SOUTH SAN FRANCISCO, California March 12, 2005 - Acumen Pharmaceuticals announced today that David Summa has joined the company as its full-time President and Chief Executive Officer. Previously, he had been the company's acting CEO since September 2002. Prior to joining Acumen, Mr. Summa was the President and CEO of Mendel Biotechnology Inc. At Mendel, Mr. Summa completed the company's Series B financing in March 2002 at a 225% step-up valuation over the Series A. Under his leadership, Mendel had strong operating success, having now functionally characterized all transcription factors in the model system arabidopsis thaliana. Prior to joining Mendel, Mr. Summa was with Monsanto, and was a partner with McKinsey & Company, Inc. in Chicago. He has a master's and bachelor's degree in chemical engineering from the Massachusetts Institute of Technology.