Myrexis presents key preclinical findings of MPI-0485520 at ACR/ARHP meeting

Myrexis, Inc. (Nasdaq:MYRX), a biotechnology company focused on discovering, developing, and commercializing novel treatments for cancer, today presented key preclinical findings of the Company's novel oral anti-interferon (OAI), MPI-0485520, at the 74th Annual Scientific Meeting of the American College of Rheumatology/Association of Rheumatology Health Professionals (ACR/ARHP), in Atlanta, Georgia.

A poster titled, "Inhibition of Cytosolic Nucleic Acid Receptor Pathways Using the Small Molecule IKKepsilon/TBK1 Kinase Inhibitor." showed that MPI-0485520 effectively suppressed the induction of several key pro-inflammatory proteins in vitro. The data supports the further evaluation of MPI-0485520 for the treatment of autoimmune disorders, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

"Our studies suggest MPI-0485520 may be an effective treatment for many autoimmune disorders, including rheumatoid arthritis and lupus" said Robert Carlson, Ph.D., Vice President and Head of Research at Myrexis. "MPI-0485520 inhibits production of type-1 interferon response and by blocking this response with our IKKepsilon inhibitor, there is the potential for disrupting disease processes."

Key Findings:

MPI-0485520 is a potent and selective inhibitor of key pro-inflammatory kinases

MPI-0485520 inhibits the activity of I kappa B kinase epsilon (IKK epsilon) and TANK-binding kinase 1 (TBK1), with picomolar potency. Conversely, MPI-0485520 did not significantly inhibit the activity of more than the 140 human kinases also tested in this study.

MPI-0485520 suppresses on-target pro-inflammatory cytokines, including IFNalpha/beta and downstream interferon-stimulated genes

The Company demonstrated that MPI-0485520 selectively inhibited production of many of the well known pro-inflammatory cytokines that are often induced in a diseased state. MPI-0485520 specifically suppressed the induction of type-1 interferon and several downstream interferon-stimulated genes including most notably, B lymphocyte stimulator (BLyS). BLys which is the target of belimumab which is currently under review by the FDA for treatment of systemic lupus erythematosus (SLE). Unlike potential competitors, MPI-0485520 is a small molecule, rather than a biologic and therefore may be developed as a daily oral therapy, and Furthermore, MPI-0485520 it targets a more central immune response regulator and thus has the potential to be effective against a variety of autoimmune diseases.

In addition, currently unpublished studies show that MPI-0485520 potently, and in a dose-dependent manner, inhibits the development of the rheumatoid arthritis phenotype in the most commonly used pre-clinical model of the disease. These results further validate this exciting new target and reveal the potential to develop effective small molecule therapeutics for a wide variety of autoimmune disorders such as rheumatoid arthritis and lupus. The Company looks forward to presenting these results and the supporting data at up-coming scientific conferences.