MedKoo product information:

ONX-0914 

Description of ONX 0914: ONX 0914 is an immunoproteasome inhibitor with potential treatment applications in autoimmune disorders, such as rheumatoid arthritis, inflammatory bowel disease and lupus.  ONX 0914 was designed to be a potent inhibitor of the immunoproteasome with minimal cross-reactivity for the constitutive proteasome. Recent evidence suggests that the immunoproteasome regulates the production of several inflammatory cytokines, including Tumor Necrosis Factor-α (TNF-α), Interleukin-6 (IL-6), IL-17, and IL-23. In preclinical models of rhematoid arthritis and lupus, ONX 0914 blocked progression of these diseases at well-tolerated doses. Preclinical studies are underway to evaluate the potential of ONX 0914 in the treatment of a range of autoimmune disorders.

Current developer:    Onyx Pharmaceuticals.

Onyx is developing ONX 0914 to be an inhibitor of the immunoproteasome, with minimal cross-reactivity for the constitutive proteasome. In preclinical models of rheumatoid arthritis and lupus, ONX 0914 blocked progression of these diseases at well tolerated doses. The Company is conducting preclinical studies to evaluate the potential clinical applications of ONX 0914 in the treatment of autoimmune disorders, such as rheumatoid arthritis, inflammatory bowel disease and lupus.

According to wikipedia.com, ONX 0914's former name was PR-957, which was developed by Proteolix. Proteolix was acquired by Onyx Pharmaceuticals in 2009 for $810 million (nominal value). Onyx renamed PR-047 to "ONX 0912" and PR-957 to "ONX 0914". (source: http://en.wikipedia.org/wiki/Proteolix).

 1: Basler M, Beck U, Kirk CJ, Groettrup M. The antiviral immune response in mice devoid of immunoproteasome activity. J Immunol. 2011 Dec 1;187(11):5548-57. Epub 2011 Oct 19. PubMed PMID: 22013127.

2: Ichikawa HT, Conley T, Muchamuel T, Jiang J, Lee S, Owen T, Barnard J, Nevarez S, Goldman BI, Kirk CJ, Looney RJ, Anolik JH. Novel proteasome inhibitors have a  beneficial effect in murine lupus via the dual inhibition of type i interferon and autoantibody secreting cells. Arthritis Rheum. 2011 Sep 8. doi: 10.1002/art.33333. [Epub ahead of print] PubMed PMID: 21905015.

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5. A selective inhibitor of the immunoproteasome subunit LMP7 blocks cytokine production and attenuates progression of experimental arthritis By Muchamuel, Tony; Basler, Michael; Aujay, Monette A.; Suzuki, Erika; Kalim, Khalid W.; Lauer, Christoph; Sylvain, Catherine; Ring, Eileen R.; Shields, Jamie; Jiang, Jing; et al From Nature Medicine (New York, NY, United States) (2009), 15(7), 781-787.

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