Sangamo BioSciences, Inc. (NASDAQ: SGMO), the leader in therapeutic genome editing, presented new preclinical data from the Company’s proprietary In Vivo Protein Replacement Platform™ (IVPRP) program in Mucopolysaccharidosis I (MPS I) providing histologic evidence of tissue clearance of toxic glycosaminoglycans (GAGs) after a single systemic treatment. Sangamo scientists and their collaborators also presented data highlighting technological enhancements of the company’s therapeutic applications, including improved AAV yields and supraphysiologic human Factor VIII (hFVIII) production in vivo, methods for highly efficient ex vivo zinc finger nuclease (ZFN)-driven targeted integration and gene knockouts at clinical scale, and treatments to enhance multipotency and long-term engraftment of ZFN-modified hematopoietic stem and progenitor cells (HSPCs)
The data were presented at the 19TH Annual Meeting of the American Society of Gene and Cell Therapy (ASGCT) which was held in Washington D.C. from May 4 to May 7, 2016.
“These histologic data, in a mouse model of MPS I, confirm earlier biochemical and cognitive studies and we are very excited to begin clinical evaluation of this program with a Phase 1/2 clinical study that will start in mid-2016,” said Edward Lanphier, Sangamo’s president and chief executive officer. “We are also pleased to report on technologic and process enhancements that the Company has made resulting in higher rates of ZFN-mediated ex vivo genome editing for both gene insertion and disruption and improved in vivo production of Factor VIII from an AAV vector, which in the past has been a notoriously difficult gene to express from a viral vector. The enhanced vector yields, combined with levels of protein expression of Factor VIII that have never been achieved before in mice or non-human primates are a testament to the engineering expertise of our research team. We look forward to updating on these studies later this year.”
New histopathological analysis revealed systemic correction of cellular vacuolation in multiple tissues of MPS I mice treated with SB-318, Sangamo’s ZFP Therapeutic candidate for the one-time, lasting treatment of MPS I. Cellular vacuolation, the engorgement of the lysosomes of a cell due to accumulation of GAGs, is a characteristic of the disease. Reduced levels of vacuolation were detected in various tissues of the treated MPS I mice, including the liver, spleen, lungs, kidney, heart and skeletal muscle, as well as in bone marrow, lymph nodes, bone and the spinal cord. Both the animal model study and histopathological analysis were performed as part of the Company’s collaboration with the University of Minnesota.
In addition to data from the Company’s IVPRP programs, Sangamo’s research team presented data on recent technological advancements in process development and therapeutic applications. Specifically:
- The optimization of AAV hFVIII cDNA vector cassettes resulting in significant improvements to both vector yields and liver-specific hFVIII expression. Historically hFVIII AAV vector cassettes routinely produce viral yields that are only 20% of non-hFVIII-encoding AAV2/6 virus preparations. Sangamo reported on vector improvements that generated virus yields that were 100% of standard AAV2/6 manufacturing yields from both mammalian (HEK293) cells at the cell factory scale, as well as insect cell (baculovirus system) manufacturing at clinical scale. This result was also observed in other AAV serotypes, including AAV2/8 and AAV2/9. Administration of AAV resulted in supraphysiologic hFVIII plasma levels (overall mean 331% of normal hFVIII expression) in a mouse model of hemophilia A at 42 days post-treatment. Supraphysiologic levels of hFVIII were also achieved in non-human primates (NHPs) (peak levels up to 887% of normal hFVIII levels, overall mean 654% at highest dose tested) at doses of only 2-6×1012 vg/kg.
- Improved multipotency, the ability to differentiate into all hematopoietic lineages, and long-term engraftment of ZFN-modified HSPCs by treatment with the small-molecule epigenetic modifier, Valproic acid (VPA). Treatment with VPA also improved rates of genome editing, particularly targeted integration, in primitive HSPCs.
- Use of serum-free conditions to increase the efficiency of ZFN-mediated targeted integration in isolated T-cells.
- Generation of highly efficient ( > 90%) levels of biallelic knock out of single genes, the T-cell receptor (TCR) and HLA Class I protein, and > 80% of both genes simultaneously in primary T-cells. In addition, the study demonstrated simultaneous highly efficient (60-70%) targeted gene integration into these sites. These methods have potential use in the development of allogeneic T-cell therapies.
Finally, Sangamo scientists and members of the Company’s senior management team were invited speakers at several scientific symposia at the meeting. Thomas Wechsler, Ph.D., project leader of the Company’s lysosomal storage disease (LSD) programs, was one of three speakers invited to present in the ASGCT Scientific Symposium, “Targeting the Liver with Gene and Cell Therapeutics.” Michael Holmes, Ph.D., Sangamo’s vice president of research, presented an overview of Sangamo’s programs in the “Special Symposium on Concepts and Clinical Applications of Genome Editing.” In addition, Dale Ando, M.D., Sangamo’s vice president of therapeutic development and chief medical officer, was one of four speakers in the Scientific Symposium, “Navigating the New RAC Review for Gene Therapy.” In his presentation, Dr. Ando discussed the new NIH Recombinant DNA Advisory Committee (RAC) review guidelines and their impact on the regulatory process for gene therapies. (Original Source)
Shares of Sangamo Biosciences closed last Friday at $5.89, up $0.07 or 1.20%. SGMO has a 1-year high of $13.57 and a 1-year low of $4.63. The stock’s 50-day moving average is $6.36 and its 200-day moving average is $6.91.
On the ratings front, Sangamo has been the subject of a number of recent research reports. In a report issued on May 3, Wells Fargo analyst Jim Birchenough reiterated a Buy rating on SGMO. Separately, on May 2, Jefferies Co.’s Gena Wang reiterated a Buy rating on the stock and has a price target of $14.
According to TipRanks.com, which ranks over 7,500 financial analysts and bloggers to gauge the performance of their past recommendations, Jim Birchenough and Gena Wang have a total average return of 25.0% and -20.4% respectively. Birchenough has a success rate of 48.0% and is ranked #38 out of 3828 analysts, while Wang has a success rate of 22.7% and is ranked #3665.
The street is mostly Bullish on SGMO stock. Out of 5 analysts who cover the stock, 5 suggest a Buy rating . The 12-month average price target assigned to the stock is $30.00, which implies an upside of 409.3% from current levels.