Sangamo BioSciences Presents Clinical Data From Key SB-728-T HIV Studies: Proof Of Concept For Ongoing Sustained Functional Control Of HIV Viral Load; Cytoxan Preconditioning Successfully Enhances Engraftment
Undetectable Viral Load Sustained Over 20 Weeks in SB-728-902 Study; Data Demonstrate Dose Response in SB-728-1101 Cytoxan Study; Reduction of Viral Reservoir Observed in All Immune Non-Responders Over Three Years
RICHMOND, Calif., Dec. 6, 2013 /PRNewswire/ -- Sangamo BioSciences, Inc. (Nasdaq: SGMO) announced today the presentation of data from all dose cohorts in the Company's ongoing clinical trials (SB-728-1101 and SB-728-902 Cohort 5) of SB-728-T, which is being developed for the functional control of HIV/AIDS. The data are being presented at the Sixth International Workshop on HIV Persistence during Therapy, considered to be the reference workshop on HIV reservoirs and eradication strategies, which is being held in Miami, FL, December 3-6 2013. (Logo: http://photos.prnewswire.com/prnh/20130102/SF35903LOGO) "The results announced today represent a major milestone," stated Geoff Nichol, M.B., Ch.B ., Sangamo's executive vice president of research and development. "We have succeeded in achieving sustained control of HIV with SB-728-T in CCR5 delta-32 heterozygotes, and we have shown that we can safely use Cytoxan to potentially achieve threshold levels of engraftment for all patients with HIV. Collectively, data from our clinical studies suggest that protection of CD4 T-cells by ZFN mediated CCR5 disruption may provide helper function to CD8 cells enabling the immune system to mount an anti-HIV response that can also erode the HIV reservoir. The reservoir is a compartment of the HIV-infected immune system that is not addressed by antiretroviral medication and its depletion is key to the goal of complete eradication of HIV infection." Sangamo's Phase 1 data suggested that if a threshold level of engraftment of SB-728-T was achieved, specifically of CD4 cells fully protected from HIV entry by zinc finger nuclease (ZFN)-mediated modification of both CCR5 genes (biallelic modification), then functional control of HIV infection may be possible. New data from the SB-728-1101 study demonstrating a clear relationship between increasing the dose of Cytoxan and increased levels of both engrafted SB-728-T and total CD4 T-cell counts further support this hypothesis and suggest that with these, or higher doses, levels of SB-728-T that will enable functional control of the virus may be reliably attained.