PCRX-201, a novel IL-1Ra gene therapy treatment approach for low back pain resulting from intervertebral disc degeneration.

Low back pain is the leading cause of global disability with intervertebral disc (IVD) degeneration a major cause. However, no current treatments target the underlying pathophysiological causes. PCRX-201 presents a novel gene therapy approach that addresses this issue. PCRX-201 codes for interleukin-1 receptor antagonist, the signalling inhibitor of the pro-inflammatory cytokine interleukin-1, which orchestrates the catabolic degeneration of the IVD. Here, the ability of PCRX-201 to transduce human nucleus pulposus cells to increase IL-1Ra production was assessed together with effects on catabolic pathways. When transduced with PCRX-201, the production and release of IL-1Ra was increased in degenerate human nucleus pulposus cells and tissue. Whereas, the production of downstream proteins, including IL-1β, IL-6, MMP3, ADAMTS4 and VEGF were decreased in both cells and tissue, indicating a reduction in IL-1-induced catabolic signalling. Here, a novel gene therapy vector, PCRX-201, was shown to transduce degenerate NP cells and tissue, increasing the production of IL-1Ra. The increased IL-1Ra resulted in decreased production of catabolic cytokines, enzymes and angiogenic factors, whilst also increasing aggrecan expression. This demonstrates PCRX-201 enables the inhibition of IL-1-driven IVD degeneration. The ability of PCRX-201 to elicit anti-catabolic responses is promising and warrants further development to determine the efficacy of this exciting, novel gene therapy.