Celgene Corporation, Sutro Biopharma Deal Could be Worth Over $500 Million

SAN FRANCISCO, Dec. 18, 2012 – Sutro Biopharma today announced a collaboration with Celgene Corporation to design and develop novel antibody drug conjugates (ADCs) and bispecific antibodies for two undisclosed targets and to manufacture a proprietary Celgene antibody. Under the terms of the agreement, Sutro will receive a substantial upfront payment, an equity investment in the company and payments for the completion of research, development and regulatory milestones. If all programs are successful, the deal could be worth over $500 million to Sutro. The company is also eligible to receive royalties on product sales.

In the collaboration, Sutro will be responsible for product design and production of preclinical materials using the company’s proprietary, cell-free protein synthesis technology. “We are pleased to work with Celgene on multiple programs that utilize a broad spectrum of Sutro’s cell free protein synthesis technology and capabilities,” said William Newell, chief executive officer of Sutro Biopharma. “The scope of this partnership showcases our novel, cell-free approach to designing, developing and manufacturing next-generation ADCs and bispecific antibodies.”

Thomas Daniel, M.D., Celgene president, global research and early development, added, “We look forward to working with the team at Sutro and to exploring their platform’s potential to accelerate the discovery and development of superior multifunctional biologics.”

Four Oaks Partners advised Sutro on the transaction.

About Sutro Biopharma

Sutro Biopharma, located in South San Francisco, is developing a new generation of antibody drug conjugate therapeutics and bifunctional antibody-based therapeutics for targeted cancer therapies. These therapeutics will significantly extend the clinical impact of current oncology therapeutic approaches and are beyond what can be envisioned with current, cell-based expression technologies. Sutro's biochemical synthesis technology, which underpins these therapeutics, allows the rapid and systematic exploration of many protein drug variants to identify drug candidates. Once these product candidates are identified, production can be rapidly and predictably scaled up to commercial levels. Sutro has established a Good Manufacturing Practice (cGMP) facility for the production of clinical supplies of materials using its biochemical protein synthesis platform. Sutro is collaborating with pharmaceutical and biotech companies in the discovery and development of novel protein therapeutics. For more information, visit www.sutrobio.com.

Martina Schwarzkopf, Ph.D.

Account Supervisor

Russo Partners, LLC

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