Custirsen

Custirsen is an investigational oligonucleotide therapeutic designed to treat various cancers. It is an antisense oligonucleotide that targets the messenger RNA (mRNA) of the protein complex Heat Shock Protein 47 (HSP47). HSP47 is a crucial chaperone protein involved in the proper folding and secretion of collagen. In the context of cancer, increased collagen synthesis and deposition can contribute to tumor growth, progression, and resistance to therapy by creating a dense tumor microenvironment.

By binding to HSP47 mRNA, custirsen aims to reduce the intracellular production of HSP47 protein. This reduction is hypothesized to disrupt the tumor's ability to synthesize and remodel its collagen matrix, thereby potentially inhibiting tumor growth, decreasing metastasis, and enhancing the efficacy of other cancer treatments.

Custirsen has been evaluated in clinical trials for several solid tumors, including metastatic castration-resistant prostate cancer and pancreatic cancer, often in combination with standard chemotherapy. While early studies showed some promise in terms of modulating the tumor microenvironment, results regarding significant clinical benefit have been mixed, and development has faced challenges. Further research is ongoing to determine its optimal role in cancer therapy.