OGX-225 is a second generation antisense drug which in preclinical experiments, inhibits production of both Insulin Growth Factor Binding Protein-2 (IGFBP-2) and Insulin Growth Factor Binding Protein-5 (IGFBP-5). Increased IGFBP-2 or IGFBP-5 production is observed in many human cancers, including prostate, non-small cell lung, breast, ovarian, bladder, pancreatic, colon, acute myeloid leukemia, acute lymphoblastic leukemia, neuroblastoma, glioma and melanoma cancers. Increased IGFBP-2 or IGFBP-5 production is linked to faster rates of cancer progression, treatment resistance and shorter survival duration in humans.

In the treatment of cancers that require hormones for growth, clinicians use hormone ablation therapy to inhibit the production of the primary hormone (e.g., testosterone or estrogen) required for tumor growth. Tumors often initially regress following hormone ablation therapy, which reduces circulating levels of tumor promoting hormones. IGFBP-2 or IGFBP 5, however, make an alternative hormone named growth factor-1 (IGF-1) that facilitates tumor growth. Inhibiting the production of IGFBP-2 and IGFBP-5, decreases tumor access to IGF-1 and in preclinical studies, reduced and delayed tumor growth.

Pre-clinical studies conducted by the Prostate Centre and others in human prostate, bladder, glioma and breast cancer, have shown that reducing IGFBP-2 and IGFBP-5 production with OGX-225 sensitized all of these tumor types to chemotherapy and also induced tumor cell death. OGX-225 has completed pre-clinical pharmacology. The goal of OGX-225 treatment will be to decrease production of IGFBP2 and IGFBP5, potentially enhancing treatment sensitivity and delaying tumor progression in patients who are resistant to hormone ablation therapy.