Feb. 26, 2018 – Silenseed announced today the allowance of USPTO Application number: 15/326044 RNA INTERFERENCE COMPOSITIONS TARGETING HEAT SHOCK PROTEIN 90 AND METHODS OF USE THEREOF (United States Patent Application 20170283803). The application disclosure relates to RNA interference (RNAi) compositions that target expression of heat shock protein 90 (HSP90) in a subject. Polymeric delivery devices for providing the RNAi compositions are also described, as are methods of treating cancer using the described RNAi compositions. Hsp90  is a molecular chaperone that regulates the maturation, activation, and stability of critical signaling proteins that drive the development and progression of prostate cancer, including androgen receptor signaling.

Prostate adenocarcinoma, as a primarily endocrine disease, is frequently dependent (at least initially) on androgens to maintain growth and viability of the tumor. Androgen receptor, Akt and Her-2 (epidermal growth factor receptor) are all important pathways in prostate cancer and significantly, all are Hsp90 client proteins. Therefore, treatments that target Hsp90 would simultaneously disrupt multiple pathways in prostate cancer. Today (2017) about 10 Hsp90 inhibitors representing multiple drug classes, with different modes of action, are undergoing clinical evaluation.