Prosetta Biosciences Inc.

Prosetta Antiviral, Inc. is an 8-year old biotechnology company developing novel small-molecule antiviral therapeutics based on over 25 years of basic research on the Cell-Free Protein Synthesizing Systems (CFPSS) by scientists at the University of California, San Francisco and the University of Washington, Seattle. The incorporation of the CFPSS in our drug discovery platform, has lead to the identification of small molecules which disrupt or alter the key protein-protein interactions involved with the assembly of viral capsids (the protein shell that protects the DNA or RNA genome of a virus). Prosetta has successfully produced highly potent compounds which display activity against multiple strains of many viral families including lead series of molecules that are effective antiviral agents against Influenza, HIV and HCV.

• Drive rapid, efficient discovery of novel antiviral compounds. Our unique Drug Discovery platform of the Cell-Free Protein Synthesizing System (CFPSS) enables Prosetta to identify novel and druggable targets for a broad range of infectious diseases and perform a rapid and efficient drug discovery/development process. We have utilized the CFPSS to identify novel protein-protein interactions, leading to the discovery of multiple chemical classes of small molecule inhibitors for all viral families addressed to date.

• The CFPSS has elucidated a pathway by which complex machines of more than a dozen host proteins catalyze capsid formation via discrete assembly intermediates for a number of viral families. The viral catalyzed capsid assembly pathway was previously not know; accordingly, the host protein targets against which Prosetta drugs are directed represent entirely new classes of anti-viral therapeutic small molecules.

• For all of our discovered antiviral compounds, our chemistry department has been able to synthesize analogue compounds that demonstrate high efficacy, low toxicity and excellent pharmacokinetic properties. Initially, we intend to partner select programs through research collaborations for each of the major viral causes of human disease (HIV, HCV and FLUV) forward through IND filing with the FDA and on through phase II human clinical trials at an early stage of development.

• We intend to expand and aggressively prosecute our intellectual property for novel antivirals that are discovered through the use of the CFPSS and are effective as modulator of the capsid assembly pathway. Because there is limited research in the field of protein catalyzed capsid formation via discrete assembly intermediates, we believe that we have established a defensible and valuable intellectual property portfolio.

• We will soon seek to commercialize our products via research and drug development partnerships with well established pharmaceutical/biotech partnerships. Initially we seek partnerships for advancing our lead series for each of HIV, HCV, and influenza.