Sangamo BioSciences, Inc. (Nasdaq: SGMO) announced today the initiation of two new Phase 2 clinical studies (SB-728-1101 and SB-728-902, Cohort 5) in its program to develop a "functional cure" for HIV/AIDS. Sangamo's ZFP Therapeutic® approach (SB-728-T) generates T-cells that are resistant to HIV infection using its zinc finger nuclease (ZFN) technology to permanently disrupt the DNA sequence encoding CCR5, a co-receptor used by HIV to enter cells. The company expects to present data from its SB-728-T HIV clinical trials at appropriate medical meetings in 2012.
"We are delighted to be able to open these two important clinical studies ahead of schedule," said Geoff Nichol, M.B. Ch.B., Sangamo's executive vice president, research and development. "Data from earlier Phase 1 trials demonstrated a statistically significant relationship between the number of circulating T-cells in which both CCR5 genes are modified and the reduction in HIV viral load in infected subjects during an interruption of anti-retroviral therapy. Both of these new Phase 2 clinical trials are specifically designed to confirm and further investigate these findings."
The new studies employ two approaches to increase the number of engrafted T-cells in which both CCR5 gene copies are modified (biallelically modified) in SB-728-T-treated, HIV-infected subjects. The first, an extension of an ongoing trial (SB-728-902, Cohort 5), is designed to further investigate the effect of SB-728-T treatment on HIV viral load in subjects that are naturally heterozygous for the CCR5 delta-32 gene mutation (i.e. one of their two CCR5 gene copies has the mutation and one is normal). The second study (SB-728-1101), in HIV-infected subjects without the CCR5 delta-32 mutation, employs a conditioning pretreatment designed to significantly enhance the number of engrafted biallelically modified T-cells.
The rationale for the Phase 2 studies is based on data obtained in a Phase 1 trial of SB-728-T that demonstrated a statistically significant relationship between the number of engrafted biallelically modified T-cells and the reduction in HIV viral load in treated subjects. In this earlier trial, the viral load of an SB-728-T treated-subject decreased to undetectable levels during a scheduled treatment interruption (TI). This subject was heterozygous for the CCR5 delta-32 gene mutation, thus doubling the number of biallelically modified T-cells after SB-728-T treatment.
"We are focused on applying our ZFP Technology platform to develop novel therapeutics to address unmet medical needs," stated Edward Lanphier, Sangamo's president and CEO. "In addition to the rapid progress that we are making in our clinical program to develop a "functional cure" for HIV/AIDS, we are advancing our preclinical ZFP Therapeutic programs to engineer genetic cures for monogenic diseases including hemophilias and hemoglobinopathies such as sickle cell anemia. Sangamo enters 2012 with a solid cash position which allows us to aggressively pursue our goals while maintaining our historic control on cash burn. As such, we plan to end 2012 with at least $60 million in cash. We look forward to providing further financial guidance for 2012 as well as an update on our clinical and preclinical programs and our corporate partnering activities on our fourth quarter and end of year 2011 call in early February."
Mr. Lanphier will also provide an update on Sangamo's ZFP Therapeutic pipeline and an overview of the Company's business strategy and objectives for 2012 during his presentation at the 30th Annual J.P. Morgan Healthcare Conference at 7:30 am PT, on Thursday, January 12, 2012.
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