Sangamo BioSciences Announces Publication of First Demonstration of In Vivo Correction of Hemophilia Gene via Systemic Delivery of a ZFP Therapeutic®

RICHMOND, Calif., June 27, 2011 /PRNewswire/ -- Sangamo BioSciences, Inc. (Nasdaq: SGMO) announced today the publication of a groundbreaking preclinical study demonstrating permanent functional correction of the gene that causes hemophilia B by the systemic delivery of zinc finger nucleases (ZFNs) .  The study, published in Nature, represents a significant advance in the development and systemic delivery of ZFP Therapeutics® and proof of concept for ZFN-based gene-editing for the treatment of hemophilia and other monogenic diseases.  

The work was carried out in the laboratory of Katherine High, M.D., Investigator, Howard Hughes Medical Institute, Professor of Pediatrics, University of Pennsylvania School of Medicine and Director, Center for Cellular and Molecular Therapeutics at The Children's Hospital of Philadelphia, in collaboration with Sangamo scientists and was published as an Advance Online Publication in Nature http://dx.doi.org/10.1038/nature10177.

"These data represent a significant advance in realizing efficient, systemic, therapeutic gene repair - the 'holy grail' of genetic medicine," said Dr. High, "With a single systemic administration of ZFNs and a donor sequence in a mouse model of hemophilia B, we demonstrated permanent correction of a defective human gene encoding the clotting factor, Factor IX, resulting in restoration of normal clotting times in the animal.  ZFN-mediated gene-editing provides a new approach to monogenic disease and circumvents the problems of traditional gene-addition strategies that result in random insertion that may lead to malignancy or other unintended consequences. Genome editing also reinstates the wild-type sequence under the control of the endogenous regulatory sequences, assuring restoration of this critical aspect of normal gene expression.  The study also demonstrated that permanent correction of the disease-related gene in situ can be achieved with therapeutically meaningful correction efficiencies."

"This is an important step forward in our goal to broaden the application of ZFN gene-editing via in vivo administration," stated Edward Lanphier, Sangamo's president and chief executive officer. "These data highlight the therapeutic potential of our ZFN technology and enable us to expand our ZFP Therapeutic pipeline to a growing number of monogenic and rare diseases."

The paper entitled "In vivo Genome Editing Restores Hemostasis in a Mouse Model of Hemophilia" described highly specific and efficient ZFN-mediated correction of a defective human Factor IX gene in a mouse model of hemophilia B by the delivery of ZFNs directly into animals.  Stable levels of Factor IX protein made from the corrected human gene were measured in the plasma of the treated animals and resulted in the restoration of normal rates of blood clotting for the eight-month duration of the study.  Moreover, the treatment was well tolerated as there were no deleterious effects on growth or liver function in the animals.

About Sangamo

Sangamo BioSciences, Inc. is focused on research and development of novel DNA-binding proteins for therapeutic gene regulation and modification.  The most advanced ZFP Therapeutic® development program is currently in a Phase 2b clinical trial for evaluation of safety and clinical effect in patients with diabetic neuropathy. Sangamo also has a Phase 1 / 2 clinical trial and two ongoing Phase 1 clinical trials to evaluate the safety and efficacy for the treatment of HIV/AIDS as well as a Phase 1 trial for the treatment for recurrent glioblastoma multiforme. Other therapeutic programs are focused on Parkinson's disease, monogenic diseases, neuropathic pain and nerve regeneration.  Sangamo's core competencies enable the engineering of a class of DNA-binding proteins known as zinc finger DNA-binding proteins (ZFPs).  By engineering ZFPs that recognize a specific DNA sequence Sangamo has created ZFP transcription factors (ZFP TFs) that can control gene expression and, consequently, cell function.  Sangamo is also developing sequence-specific ZFP Nucleases (ZFNs) for gene modification.  Sangamo has established strategic partnerships with companies in non-therapeutic applications of its technology including Dow AgroSciences and Sigma-Aldrich Corporation. For more information about Sangamo, visit the company's website at www.sangamo.com.

ZFP Therapeutic® is a registered trademark of Sangamo BioSciences, Inc.

This press release may contain forward-looking statements based on Sangamo's current expectations. These forward-looking statements include, without limitation, the potential of ZFNs to treat human monogenic diseases such as hemophilia and other rare diseases, research and development of novel ZFP TFs and ZFNs and therapeutic applications of Sangamo's ZFP technology platform. Actual results may differ materially from these forward-looking statements due to a number of factors, including uncertainties relating to the initiation and completion of stages of our clinical trials, whether the clinical trials will validate and support the tolerability and efficacy of ZFNs, technological challenges, Sangamo's ability to develop commercially viable products and technological developments by our competitors. For a more detailed discussion of these and other risks, please see Sangamo's SEC filings, including the risk factors described in its Annual Report on Form 10-K and its most recent Quarterly Report on Form 10-Q. Sangamo assumes no obligation to update the forward-looking information contained in this press release.

SOURCE Sangamo BioSciences, Inc.