Oct. 20, 2009 (PR Newswire) -- RICHMOND, Calif., Oct. 20 /PRNewswire-FirstCall/ -- Sangamo BioSciences, Inc. (Nasdaq: SGMO) announced today the presentation of top-line, statistically significant Phase 2 clinical data from its ZFP Therapeutic(TM) program to develop SB-509 as a treatment for diabetic neuropathy (DN) at the Society for Neuroscience Annual Meeting held in Chicago.

Top-line data from Sangamo's SB-509-601 Phase 2 clinical trial demonstrated a direct neuroregenerative effect of SB-509 treatment that resulted in a statistically significant (p value=0.02) increase in small unmyelinated nerve fibers in the skin, or intraepidermal nerve fiber density (IENFD), in subjects with DN.

Data were also presented that provided additional evidence of the positive effect of SB-509 on large fiber sensory nerve health as measured by improvements in nerve conduction velocity (NCV), in subjects with elevated markers of vascular damage (ICAM-1), and improvements in the muscle components of the neurologic exam (NIS-LL) 30-days after each of the three administrations of SB-509. Together these data confirm the neuroregenerative activity of SB-509 in patients with DN and define a drug-responsive population for future trials.

"The IENFD data presented today provide direct histologic evidence of nerve regrowth with SB-509 treatment and a mechanistic proof of concept for the neuroregenerative effects of this ZFP Therapeutic," stated Dale Ando, M.D., Sangamo's Vice President of Therapeutic Development and Chief Medical Officer. "The relationship between reduced IENFD and severity of DN has been well established and correlates with decreased levels of VEGF-A and an increase in inflammatory growth factors such as ICAM-1, a marker of vascular disease. In addition, in subjects with more severe DN, with elevated levels of ICAM-1 in their blood, there is a greater improvement in sural NCV in SB-509 treated subjects. Together these data provide support for our hypothesis that the dual neuroregenerative and angiogenic functions of SB-509 are important for improvement of nerve health by counteracting the pathologic effects of diabetes on nerves and blood vessels in these subjects. In future clinical studies, IENFD and ICAM-1 levels will serve as an important baseline measurement to aid in identification of a target population of SB-509 responsive DN patients and as a stratification variable to ensure that we have well-balanced treatment and placebo groups."

IENFD is a validated, direct biologic measurement of small unmyelinated sensory nerve fibers in the skin, the primary nerves involved in DN. It has also been demonstrated to correlate with neuropathy severity in diabetes, nerve fiber densities derived from sural nerve biopsies and levels of vascular endothelial growth factor-A (VEGF-A).

Data were also presented that demonstrate that in subjects with more severe neuropathy, as judged by their baseline IENFD, a greater nerve regrowth response to SB-509 treatment was observed compared to regrowth responses in placebo-treated subjects. In addition, subgroup analyses using baseline severity of disease as a selection criterion, demonstrated that SB-509 treatment resulted in correlative clinically relevant improvements in NIS-LL and sural NCV in subjects with moderate to severe disease.

"Loss of small unmyelinated nerve fibers is an early symptom of DN and the positive IENFD data have given us insight into the population of subjects that we expect will show the greatest response to SB-509 treatment over the 180 day clinical study period," said Edward Lanphier, Sangamo's president and CEO. "This is the first large placebo controlled study to show the value of IENFD in clinical studies of DN and we have gathered a significant amount of clinically relevant correlative data that will aid in the development of future clinical studies. We are grateful to the Juvenile Diabetes Research Foundation for their support and funding of our studies using this promising endpoint."

Details of Presentation of IENFD Data from SB-509-601 Study

Tuesday, October 20, 2009

    --  "Epidermal nerve fiber density and regeneration with vascular
endothelial growth factor zinc finger protein activator (SB-509) in mild
to moderate diabetic peripheral neuropathy patients. (SB-509-0601
study)." M. Polydefkis(1), P. Haurei(1), *E. Benaim(2), D. Ando(2), S.
Hamilton(2), H. Kim(2), S. Study Group(2); (1) Johns Hopkins Univ.,
Baltimore, MD; (2) Clin. Affairs, Sangamo BioSciences, Richmond, CA

IENFD and IENFD Regrowth (IENFDR) measurements were prospectively defined endpoints in Sangamo's double-blind, repeat dosing Phase 2 clinical study (SB-509-601) in which subjects were treated at 0, 60 and 120 days.