On October 02, 2017 Spring Bank Pharmaceuticals, Inc. (NASDAQ:SBPH), a clinical-stage biopharmaceutical company developing novel therapeutics for the treatment of viral infections, inflammatory diseases and certain cancers, reported that it will present a poster (#A25) at 5:30 p.m. to 7:30 p.m. today, October 2, 2017, entitled “Pharmacodynamic and preclinical studies of SB 11285, a highly potent, and systemically bioavailable STING agonist as a novel immunotherapeutic agent,” at the AACR (Free AACR Whitepaper) Conference on Tumor Immunology and Immunotherapy, taking place in Boston, MA, October 1-4, 2017 (Press release, Spring Bank Pharmaceuticals, OCT 2, 2017, View Source [SID1234520749]). The data shows that Spring Bank Pharmaceuticals’ next-generation, proprietary STING (STimulator of INterferon Genes) agonist compound, SB 11285, has highly potent anti-tumor activity along with a durable anti-tumor response when administered by multiple routes in several tumor models.
“Data from multiple tumor models in preclinical studies of SB 11285 demonstrated durable antitumor activity and support continued development of SB 11285, either alone or in combination with other agents, with different routes of administration,” said Radhakrishnan (Kris) Iyer, Ph.D., Chief Scientific Officer of Spring Bank Pharmaceuticals. “We are conducting additional preclinical and IND-enabling studies to support the initiation of the SB 11285 clinical program in mid-2018.”
SB 11285 was evaluated in several syngeneic mouse models, including A20 lymphoma, CT26 colon carcinoma, B16 melanoma, and orthotopic 4T1 breast cancer models, for tumor growth inhibition (TGI) and tumor growth delay (TGD). SB 11285 was administered by intravenous (i.v.), intraperitoneal (i.p.), and intra-tumoral (i.t.) routes. The results are summarized here:
A20 Lymphoma Model: When SB 11285 was administered by i.t. route, 9 out of 10 animals achieved complete regression with 86% tumor growth inhibition (TGI) and 73% tumor growth delay (TGD). Furthermore, all tumor-free survivors rejected the tumors when re-challenged with A20 cells indicating the induction of immune memory.
CT26 Colon Carcinoma Model: Dose-ranging studies of SB 11285 were performed using i.t. doses (10 to 100µg on days 1,2,4,6,8), i.p. (1 to 9 mg/kg) and i.v. (1 to 9mg/kg, days 1,3,5,8). Highly durable anti-tumoral responses were seen in the CT26 models with i.t. (94% TGI & 207% TGD), i.p. (62% TGI & 49% TGD), and i.v. (80% TGI & 85% TGD). SB 11285 administered i.t. also showed a significant abscopal effect (a shrinkage of tumors beyond the scope of the localized treatment) in this model.
B16 Melanoma Model: Administration of SB 11285 resulted in 77% and 56% reductions in mean tumor volumes, when administered i.v. and i.p., respectively, by day 11 post-treatment.
4T1 Breast Cancer Model: SB 11285 administered i.p. resulted in 78% reduction in primary tumor volume and showed potent inhibition of tumor metastasis.
The anti-tumor activity observed in these models correlated with anti-tumoral immune response. Immuno-histochemistry combined with flow cytometric analysis of tissues and blood from SB 11285-treated groups revealed the presence of activated immune cells, including CD8+ T cells, natural killer (NK) cells and macrophages critical for anti-tumor effects.
About the AACR (Free AACR Whitepaper) Special Conference on Tumor Immunology and Immunotherapy
The AACR (Free AACR Whitepaper) Special Conference on Tumor Immunology and Immunotherapy is focusing on recent advances in understanding the range of immune responses towards cancer and how these can be modified and harnessed for prevention and therapeutics. The conference features the world’s premier oncologists who will present their latest research on current immunotherapies, engineered cells, checkpoints, and combinations. In addition, highly acclaimed basic researchers and immunologists will present data that bridge the gap between the cutting-edge advances that are under way in the lab, such as single-cell analysis, neoantigens, systems and synthetic biology, and their application to clinical practice.