Sirna Announces Management Changes

Sirna Therapeutics has announced the appointment of R. Scott Greer to Chairman of the Board and Lutz Lingnau as a new member of the Board of Directors.

Mr. Greer, currently a member of Sirna's Board of Directors, will now serve as its Chairman. Mr. Greer is also Chairman of the Board of Abgenix, Inc. and Acologix, Inc., both biopharmaceutical companies.

In the past, he has served on the boards of CV Therapeutics, Inc. and Illumina, Inc., as well as several private companies.

After founding Abgenix in 1996, Mr. Greer served as its Chief Executive Officer until 2002.

In December 2005, Abgenix announced that it had entered into a definitive agreement to sell the company to Amgen for $2.2 billion. Mr. Greer also is managing director of Numenor Ventures LLC.

"After having served on the Sirna Therapeutics Board for the past two years, I am excited to have the opportunity to sit as Chairman," said Mr. Greer.

"The company is executing well on both its business and R&D strategies and is poised to capitalize on what is likely to be one of the most important breakthroughs in human medicine - RNAi-based therapeutics."

Mr. Lingnau was a member of the Executive Board of Schering AG. At Schering, he was responsible for their worldwide specialized therapeutics and dermatology businesses.

Mr. Lingnau was also President and Chief Executive Officer of Berlex Laboratories, Inc., Schering AG's U.S. pharmaceutical group.

Mr. Lingnau is currently a member of the Supervisory Board of Lanxess AG, a global chemical manufacturing company.

Mr. Lingnau said, "I am very pleased to join the Board of Sirna Therapeutics. With world-class chemists and biologists advancing siRNAs from the lab to the clinic, Sirna is making great progress in bringing important therapeutics to the market."

"Sirna's outlook is exciting and I look forward to working with Sirna's management team in further developing their short and long-term business strategies."

"We are pleased to have Scott take over the leadership of the Board and welcome the vast pharmaceutical experience Lutz brings to Sirna," stated Howard W. Robin, President and CEO of Sirna.

"As Sirna continues to drive multiple programs through the clinic, it is imperative for us to capitalize on the experience and expertise of individuals who have been part of similar successes in their careers."

"Both Scott and Lutz bring significant insight into the challenges and opportunities Sirna is likely to encounter as we become a world leader in RNAi-based therapeutics. They will undoubtedly aid us in advancing our business strategy and building shareholder value."

"Over the past three years, the company has progressed from being a world leader in RNA chemistry and biology to being a world leader in RNAi-based therapeutics," stated James Niedel, M.D., Ph.D., and former Chairman of the Board.

"Scott's skills and experiences will serve Sirna well as the company continues this progress by growing its capabilities, expanding its partnerships and moving more programs into the clinic."

"I look forward to continuing as a Sirna Director and to working with Scott and Howard as they establish RNAi as an important therapeutic modality."