Sutro Biopharma Hits Major Technical Milestone, Reaching 100 Liter Scale for the Company’s Open Cell-free Protein Synthesis Technology – Milestone Triggers $15 Million Series B Financing

Mar 30, 2009

South San Francisco, CA (March 30, 2009) Sutro Biopharma, Inc., a pioneer in open cell-free synthesis for the discovery and production of proteins, announced today the first ever achievement of therapeutic protein production at 100 L scale using a cell-free synthesis technology.
“We are excited and encouraged to have met this important development goal,” said William J. Newell, Sutro Biopharma’s chief executive officer. “The 100 L scale protein synthesis, using our proprietary Open Cell-free Synthesis (OCFS) technology, is unprecedented in the industry. In terms of our development path, this accomplishment now places us within reach of commercial scalability.”
Sutro’s success also marked a major financing milestone, triggering a $15 million second tranche of its previously announced Series B Preferred Stock financing. SV Life Sciences and Alta Partners co-led the Series B round.
Employing its patented cell-free synthesis technology, Sutro scientists successfully produced a therapeutic cytokine in a 100 L scale reaction, demonstrating linear scalability from micro-liter scale to 100 L scale. The protein product was purified, formulated, and characterized and shown to be of pharmaceutical quality. Sutro has exclusively licensed the OCFS technology from Stanford University where it had been developed by Professor James Swartz.
“The demonstration of successful linear scalability for our open cell-free protein synthesis is an important scientific achievement for Sutro and for the future of the protein therapeutic industry,” noted Daniel Gold, Ph.D., Sutro Biopharma’s president and chief operating officer. “This achievement allows us to use our platform at a micro-liter scale for protein discovery and modification with the confidence that new molecules can be immediately scaled for development and eventual commercialization — thus avoiding the delays and challenges of cell line development inherent in cell-based systems. The fidelity, purity, and speed of this protein synthesis are remarkable.”
Michael Ross, Ph.D., managing partner at SV Life Sciences, commented, “We are very pleased with the rapid scientific progress made by Sutro Biopharma. We believe this emerging platform technology will be of significant interest to pharmaceutical and biotechnology companies creating and developing new and modified protein therapeutics.”

About Sutro’s Open Cell-Free Synthesis (OCFS) Technology

OCFS technology is an open, cell-free synthesis system designed for use at research through commercial scale that employs controlled, catalytically driven biochemical reactions to make protein-based therapeutics. An open, cell-free architecture is free from mass transport constraints of the cell wall and membrane, as well as requirements for cell growth and viability. The system is thus devoid of the compartmentalization that is generally required for protein folding. Sutro has demonstrated proof-of-concept for the OCFS technology with proteins currently produced in mammalian, yeast, and bacterial systems, such as clinically validated growth factors, Fab’s, scFv’s, and vaccines.

About Sutro Biopharma, Inc.

Sutro Biopharma, Inc. is a biopharmaceutical company that uses its patented technology collaboratively to develop novel biomedicines for the treatment of human disease. This commercially scalable technology overcomes many of the limitations frequently associated with mammalian, yeast and bacterial systems. The company’s technology is applicable to the discovery and production of novel therapeutic proteins, including peptides and enzymes, and antibodies and antibody fragments, and can be utilized to discover and produce novel hybrid proteins for therapeutic use. The company’s technology can also be utilized to provide novel functionalities that will improve the therapeutic profile of biopharmaceutical products.

Contact:

William J. Newell
CEO
Sutro Biopharma, Inc.
Phone: (866) 921-8942 x146
bnewell@sutrobio.com

For Media:

Joan Kureczka
Kureczka/Martin Associates
(415) 821-2413
Jkureczka@comcast.net