Soligenix, Inc. announced that dusquetide is effective at reducing tumor size in nonclinical xenograft models. Recent studies, recapitulating results from previously published studies, have confirmed the efficacy of dusquetide as a stand-alone and combination anti-tumor therapy, with radiation, chemotherapy and targeted therapy, in the context of the MCF-7 breast cancer cell line. Dusquetide previously demonstrated benefits in reducing the duration of severe oral mucositis (SOM) in a Phase 2 clinical trial and reduction in SOM rates in the per protocol population in a Phase 3 study.

In addition to the reduction of severe oral mucositis, an acceleration in the clearance of tumor response and an increase in overall survival were also observed in the Phase 2 clinical study as an ancillary benefit to treating oral mucositis in patients receiving chemo-radiation for their head and neck cancer (HNC). Based on the biological proof of principle shown both nonclinically and clinically with dusquetide, a novel synthetic peptide that modulates the body's innate immune system, Soligenix continues to explore product opportunities, both in the reduction of oral mucositis in HNC and as a potential anti-cancer treatment. Dusquetide binds to p62 or SQSTM-1, a scaffold protein implicated in a number of intracellular signaling networks implicated in tumor cell survival, including autophagy.

The role of p62 is best characterized in multiple myeloma and breast cancer. All variants of breast cancer, including metastatic breast cancer, estrogen receptor positive (ER+), human epidermal growth factor receptor 2 high expressing (HER2+) and triple negative expressing cell lines, have demonstrated a significant role for p62 in tumorigenesis. The MCF-7 cell line tested in the xenograft studies with dusquetide is both ER+ and responsive to anti-HER2 treatment.

Treatment with dusquetide was effective not only as a stand-alone treatment (p<0.01 for tumor size), but also in conjunction with radiation (p<0.05 vs radiation only for survival), chemotherapy (paclitaxel) and targeted treatment (trastuzumab; p<0.001 vs. placebo only for tumor size), reducing tumor size and enhancing overall survival. Other tumor types also have been shown to be dependent on p62 expression, including multiple myeloma, liver cancer (hepatocellular carcinoma), lung cancer (non-small cell lung cancer, EGFR-TKI-resistant lung cancer), intestinal cancer (small intestinal adenocarcinoma and gastric cancer), and colorectal cancer and ovarian cancer (multi-drug resistant).