July 28, 2011

Sorrento Therapeutics Awarded Phase I STTR Grant for C. difficile Program

SAN DIEGO, July 28, 2011 /PRNewswire/ --Sorrento Therapeutics, Inc. (OTC Bulletin Board: SRNE) announced today that it has received a Phase I Small Business Technology Transfer Research (STTR) grant from the National Institute of Allergy and Infectious Diseases of the National Institutes of Health (NIH). This peer-reviewed grant was awarded to support the Company's program to generate and develop antibody therapeutics and vaccines to combat Clostridium difficile (C. difficile or C. diff) infections by disrupting quorum sensing, a bacterial communication process believed to control virulence. The Phase I grant is for $300,000 per year for two years, with the possibility of Phase II funding of $1 million per year for up to an additional 3 years.

C. difficile is the most common cause of hospital-acquired infectious diarrhea (C. difficile-associated diarrhea or CDAD). According to the Centers for Disease Control, the annual incidence of CDAD infections in the United States is approximately 478,000 cases: 165,000 in hospitals, 50,000 post hospital discharge, and 263,000 in nursing homes. With an overall mortality rate of 6-7%, CDAD infections impose an estimated financial burden of over $3.9 billion per year on the U.S. healthcare system. The situation is worsening with the emergence of hypervirulent and multi-drug resistant forms. "It is clear that the NIH remains motivated to fund novel approaches to tackling the serious healthcare burden of C. diff. Together with our NIAID-funded program for the control of S. aureus, the Company is targeting the two most prevalent nosocomial infections in the U.S.," said Henry Ji, Ph.D., Chief Scientific Officer and interim Chief Executive Officer of Sorrento Therapeutics.

About the Sorrento Therapeutics C. diff Program

Sorrento Therapeutics has an exclusive worldwide license to utilize the quorum sensing technology developed at The Scripps Research Institute (TSRI), which is the basis for its anti-infectives programs. The importance of the technology is that it targets specific auto-inducing peptides (AIPs) central to the quorum sensing system of C. difficile. Squelching these AIPs leads to a disruption of bacterial communication ("quorum quenching") and could suppress virulence. The grant application was noted to be a highly innovative approach that could potentially expand the technology platform into additional disease indications.

About Sorrento Therapeutics

Sorrento Therapeutics, Inc. is a development-stage biopharmaceutical company leveraging its proprietary turn-key human antibody libraries for the discovery and development of human therapeutic antibody products for the treatment of a variety of disease conditions, including cancer, inflammation, metabolic diseases and infectious diseases. More information is available at www.sorrentotherapeutics.com. Information on the Company's website or any other website does not constitute a part of this press release.

Forward-Looking Statements

This press release contains forward-looking statements subject to risks and uncertainties that could cause actual results to differ materially from those projected. Forward-looking statements include statements about Sorrento Therapeutics' C. diff program and its prospects, the research and development opportunities presented by the Company's license agreement with TSRI, Sorrento Therapeutics' potential opportunity to receive future funding for the second year of the Phase I grant and a Phase II grant for the C. diff program from the NIH, and the Company's potential development of human vaccines and antibody therapeutics. Risks and uncertainties include whether Sorrento Therapeutics will have sufficient resources to develop vaccines and antibody therapeutics, whether Sorrento Therapeutics will achieve its goals through the license agreement, the term of the license, the Company's ability to collaborate with TSRI and its researchers in the future, whether the Company will seek or gain regulatory approval to market any product candidates in the U.S. or internationally, whether the Company will continue to develop and protect its intellectual property and additional risks set forth in Sorrento Therapeutics' filings with the Securities and Exchange Commission. These forward-looking statements represent Sorrento Therapeutics' judgment as of the date of this release. The Company disclaims, however, any intent or obligation to update these forward-looking statements.

Acknowledgement of NIH Support

The project described was supported by Award Number R41AI096839 from the National Institute of Allergy And Infectious Diseases. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Allergy and Infectious Diseases or the NI H.

SOURCE Sorrento Therapeutics, Inc.