Sangamo BioSciences ZFP Therapeutic Program In HIV/AIDS Featured At Three Major Scientific Conferences In October 2014

Sangamo BioSciences, Inc.

announced that Company scientists and clinicians, as well as academic collaborators, were invited speakers at three major scientific meetings in Europe and the United States. Their presentations covered a number of therapeutic uses of Sangamo's novel zinc finger protein (ZFP) technology, but were primarily focused on reviewing the progress of the Company's ZFP Therapeutic® program in HIV/AIDS. Presentations included a review of current clinical data with SB-728-T as well as the design of Sangamo's ongoing Phase 2 clinical trial (SB-728-mR-1401) and the preclinical rationale for targeting CCR5 in hematopoietic stem cells, which is expected to enter clinical testing in late 2014. "Participation in these key scientific forums—the NIH 'Strategies for an HIV Cure 2014' meeting, the European Society of Gene and Cell Therapy (ESGCT) Annual Meeting, and most recently, the British HIV Association (BHIVA) Autumn Conference—underscores the tremendous interest from the international scientific and clinical communities in Sangamo's progress toward developing a ZFP Therapeutic that may replicate natural, durable resistance to HIV infection," said Edward Lanphier, Sangamo's president and CEO. "Sangamo's ongoing Phase 2 trial incorporates all that we have learned from previous trials about the potential mechanism of this novel therapeutic clinical approach, and we believe the data produced will provide a clear path to pivotal studies. We expect to accrue all subjects onto the clinical trial by the end of 2014 and to present data in 2015." This week, October 15-17, at the "Strategies for an HIV Cure 2014" conference organized by the National Institute for Allergies and Infectious Diseases at the NIH, Philip Gregory, D.Phil., Sangamo's senior vice president, research, and CSO, will present an overview of the SB-728-T program, along with Sangamo collaborators Paula Cannon, Ph.D., Associate Professor Molecular Microbiology & Immunology, Pediatrics, Biochemistry & Molecular Biology, Keck School of Medicine, University of Southern California; Pablo Tebas, M.D., Professor of Medicine at the Hospital of the University of Pennsylvania; and Hans-Peter Kiem, M.D., Jose Carreras/E. Donnall Thomas Endowed Chair for Cancer Research at the Fred Hutchinson Cancer Research Center. Dr. Gregory will also be presenting an overview of the SB-728-T clinical program at a "bench to bedside" discussion forum of the annual ESGCT meeting, October 23-26, which will be held in The Hague. Dr. Gregory and Sangamo collaborator Luigi Naldini, M.D., Ph.D., Director, San Raffaele Telethon Institute for Gene Therapy (TIGET) will discuss the larger field of genome editing, utilizing the company's HIV studies as a model. Sangamo collaborators will also be discussing the use of Sangamo zinc finger nucleases in preclinical and research studies of SCID-X1, cancer and Wiskott-Aldrich Syndrome. Earlier in October, Geoffrey Nichol, M.B., Ch.B., Sangamo's executive vice president, research and development, was invited to deliver the Foundation Lecture, reviewing recent clinical data from the SB-728-T program at the Autumn Conference of the British HIV Association which was held in London, UK. Sangamo's SB-728-mR-1401 trial is an open-label, multi-center study designed primarily to evaluate safety and tolerability and the effect of repeat doses of SB-728-T following optimal cyclophosphamide (Cytoxan®) pre-conditioning, on engraftment, viral load and total CD4 counts in peripheral blood. Electroporation of mRNA is being used to deliver the zinc finger nucleases to a subject's T-cells to generate the modified autologous T-cell product (SB-728-T). mRNA delivery is more efficient than the previous adenoviral delivery method used and enables treatment of subjects with multiple doses of CCR5-modified cells. Up to nine subjects will be enrolled into two cohorts. Each subject will receive a total of up to 40 billion ZFN modified T-cells. The first cohort will receive this dose divided into infusions of two equal doses of SB-728mR-T 14 days apart after a cyclophosphamide (1 g/m2) preconditioning treatment two days prior to the first SB-728mR-T infusion, and the second cohort will receive three doses of cells. Dividing the total cell dose and administering sequentially in this manner is thought to maximize overall cell engraftment. Four weeks after the last SB-728-mR infusion, subjects with CD4 cell counts ≥500 cells/mm3 will undergo a 16 week treatment interruption (TI) during which time their anti-retroviral therapy will be discontinued.