Sirtris CEO Christoph Westphal Joins IDG Ventures As Advisor; Will Serve as Senior Advisor and Chairman of IDG Venture’s Life Sciences Advisory Board

BOSTON, MA – SEPTEMBER 13, 2006 – IDG Ventures, an early-stage venture capital firm focused on investing in information and healthcare technology companies, today announced that Christoph Westphal, co-founder and CEO of Sirtris Pharmaceuticals, will join the firm as a Senior Advisor and Chairman of its Life Sciences Advisory Board. As a serial entrepreneur Westphal has co-founded 5 companies as CEO or Chairman, including Alnylam Pharmaceuticals (NASDAQ: ALNY), Momenta Pharmaceuticals (NASDAQ: MNTA), Magen Biosciences, Acceleron Pharma and Sirtris Pharmaceuticals. In addition, he brings a successful life sciences investment track record, having served as a General Partner at Polaris Venture Partners where he led 10 investments.

Working exclusively with IDG Ventures as a Senior Advisor, Westphal will work with the IDG Ventures general partners to further the firm's life sciences investment initiatives. For example, IDG Ventures recently participated in a $15.4 million Series A investment in Magen Biosciences, a company Westphal co-founded as Chairman with Nobel Prize Winner and Biogen and Alnylam Co-founder Phil Sharp. In addition, he will support the formation of the IDG Ventures Life Sciences Advisory Board, serving as its Chairman. Westphal will continue to serve as CEO of Sirtris Pharmaceuticals in his new role with IDG Ventures.

"Christoph is one of the most successful and highly respected investors and entrepreneurs in the life sciences community," said Michael Greeley, founder and general partner, IDG Ventures. "As we looked to broaden our investment scope in the life sciences sector, we wanted to add someone with the expertise to help our existing portfolio, as well as the network to bring world-class investment opportunities into the firm. Having worked with him at Polaris Venture Partners, I know there is simply no one out there better than Christoph for this role and we are thrilled to have him join our team."

"I've worked with the IDG Ventures team for a number of years and am thrilled to join the firm as an advisor to help build the next generation of successful life sciences companies," said Westphal.

Westphal serves as Chief Executive Officer and Vice Chairman of Sirtris Pharmaceuticals, a biopharmaceutical company developing and commercializing novel therapeutics that modulate sirtuins, a recently discovered family of enzymes that promotes the body's natural defense against disease. Prior to Sirtris, he was a General Partner at Polaris Ventures Partners. While at Polaris, Westphal co-founded, invested in, and served as CEO and Vice Chairman of Alnylam Pharmaceuticals (NASDAQ: ALNY), Momenta Pharmaceuticals (NASDAQ: MNTA), and Acceleron Pharma. Westphal also co-founded Nanosys and led investments in Advion Biosciences, Athenix, GI Dynamics, Hydra Biosciences and Saegis Pharmaceuticals. Previously he was with McKinsey and Company's healthcare practice.

Westphal earned a BA from Columbia University and received his M.D. and Ph.D. from Harvard Medical School. He has received numerous awards and recognitions including the 2006 Ernst & Young New England Biotech Entrepreneur of the Award, Boston Business Journal "40 Under 40" Award, and the MIT Technology Review 100 Award.

About IDG Ventures Boston

IDG Ventures Boston is a leading venture capital firm focused on investing in early-stage information and healthcare technology companies. With $280 million under management, the firm is an independent partnership making investments on behalf of its limited partners. The fund is affiliated with IDG Ventures, a global $1.4 billion network of funds spanning Asia and North America. International Data Group, the world's largest IT media, research, and event company, is one of the limited partners for IDG Ventures Boston. Through the IDG global network, IDG Ventures Boston is able to uniquely add value to its portfolio companies by facilitating revenue acceleration and global expansion and establishing relationships with key strategic partners. For more information, visit .