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Sangame Sangamo Therapeutics Reports Recent Business and Clinical Highlights and Third Quarter 2021 Financial Results November 4 , 2021 THERAPEUTICS Conference Call and Webcast Scheduled for 9:15 a.m. Eastern Time BRISBANE , Calif .-- ( BUSINESS WIRE ) -- Nov . 4 , 2021-- Sangamo Therapeutics , Inc. ( Nasdaq : SGMO ) , a genomic medicine company , today reported third quarter financial results and provided business and clinical highlights . " We are delighted to share clinical data and business updates across several programs demonstrating that Sangamo has three important assets progressing toward late - stage development . Our gene therapy portfolio is advancing with accumulating safety and efficacy data in our Fabry and hemophilia A programs , and preliminary proof - of - concept data demonstrate the clinical potential of our zinc finger genome engineering technology in sickle cell disease . These data readouts show the progression of our first - generation genomic medicine pipeline and potentially pave the way for new treatments . Our next generation programs focus on genome regulation and allogeneic CAR - Treg cell therapy , where we have a robust preclinical pipeline in neurological and autoimmune diseases . We are energized by this momentum and look forward to continued execution of our corporate strategy , " said Sandy Macrae , Chief Executive Officer of Sangamo . Recent Clinical and Business Highlights Fabry Disease - First four patients dosed exhibited above normal a - Gal A activity ; Phase 3 planning initiated • Earlier today , we announced preliminary clinical data from the first four patients treated in our Phase 1/2 STAAR study evaluating isaralgagene civaparvovec , or ST - 920 , our wholly owned Fabry disease gene therapy product candidate . Data as of the September 17 , 2021 cutoff date from the four patients in the first two dose cohorts showed that isaralgagene civaparvovec was generally well tolerated . All four patients exhibited above normal alpha - galactosidase A ( a - Gal A ) activity , which was maintained for up to one year for the first patient treated and through 14 weeks for the most recently treated patient . Activity of 2 - fold to 15 - fold above mean normal was observed at last measurement as of the cutoff date . Withdrawal from enzyme replacement therapy ( ERT ) has taken place for one patient and is planned for the other patient on ERT , based on the stability of their a - Gal A activity following treatment . • The fifth patient in the STAAR study , who is the first patient in the third cohort ( 3e13vg / kg ) , was dosed after the cutoff date . The sixth patient is currently in screening also for the third dose cohort . We expect to provide updated data throughout 2022 and present these results at a medical meeting . • Based on the STAAR study results to date , we have initiated planning for a Phase 3 Fabry disease clinical trial . Sickle Cell Disease - Preliminary - proof - of - concept data will be presented at ASH as clinical program advances • Preliminary proof - of - concept results from the Phase 1/2 PRECIZN - 1 study investigating SAR445136 , formerly BIVV003 , an investigational zinc finger nuclease gene edited cell therapy , in patients with severe sickle cell disease ( SCD ) will be presented at the 63rd Annual Meeting of the American Society of Hematology ( ASH ) on December 12 , 2021. Results as of the June 25 , 2021 cutoff date show that all four treated patients did not require blood transfusions post engraftment and had no adverse or serious adverse events related to SAR445136 through 65 weeks of follow - up for the longest treated patient . The four treated patients all experienced increases in total hemoglobin , fetal hemoglobin and percent F cells . • We and Sanofi continue to advance the sickle cell disease program . We recently obtained manufacturing requirements guidance from FDA in preparation for further potential clinical studies . Separately , we and Sanofi made the business decision to cease development of the beta thalassemia indication in order to focus resources on the sickle cell disease program . ST - 400 for beta thalassemia was developed with the support of a grant from the California Institute for Regenerative Medicine ( CIRM ) . Hemophilia A - Four patients at highest dose experienced mean FVIII activity of 30.9 % at week 104 • Updated follow - up results from the Phase 1/2 Alta study of giroctocogene fitelparvovec gene therapy in patients with severe hemophilia A will be presented at ASH on December 12 , 2021. For the four patients in the highest dose 3e13vg / kg cohort who have reached 104 weeks of follow - up as of the May 19 , 2021 cutoff date , mean Factor VIII ( FVIII ) activity was 30.9 % at week 104 as measured by chromogenic assay . In this cohort , the annualized bleeding rate was zero for the first year after treatment and 0.9 throughout total duration of follow - up . Giroctocogene fitelparvovec was generally well tolerated . • We and Pfizer also announced that some of the patients treated in the Phase 3 AFFINE trial of giroctocogene fitelparvovec experienced FVIII activity greater than 150 % following treatment . None of these patients have experienced thrombotic events and some have been treated with direct oral anticoagulants to reduce thrombotic risk . Pfizer voluntarily paused