Researchers Report in Neuroscience that TB4 Improves Neurological Function after Stroke

RegeneRx Biopharmaceuticals, Inc. (NYSE Amex:RGN) (“the Company” or “RegeneRx”) today announced a research team from the Henry Ford Hospital in Detroit, MI, reported that Thymosin beta 4 (Tβ4), administered to rats after embolic stroke, improved neurological functional outcome compared to control animals.

The research was conducted by Dr. Daniel Morris and his colleagues at the Department of Emergency Medicine, Henry Ford Health System, Detroit, MI, and published in Neuroscience, 2010 Aug 25 169(2) 674-682, http://www.ncbi.nlm.nih.gov/pubmed/20627173. The research was performed under a Material Transfer Agreement between RegeneRx Biopharmaceuticals, Inc. and the Henry Ford Health System.

Improvement in neurological function was measured at various time intervals over a seven week period and was statistically significant. A statistically significant increase in remyelination of axons and vessel density in the ischemic boundary was also observed between rats receiving Tβ4 vs. controls, likely due to an increased mobilization of oligodendrocyte progenitor cells (brain stem cells that differentiate into cells that protect nerve fibers). mRNA levels for the epidermal growth factor receptor were determined in both normal and stroke rats treated with Tβ4 and were approximately 50% higher in the stroke-treated rats. This receptor has previously been shown to be a key regulator of progenitor cell expansion and tissue regeneration in response to brain injury and further confirms the role of Tβ4 in stem cell-mediated tissue repair.

“Some of these data were previously reported at an International Stroke Conference in March; however, the data published today include more specific information on functional remodeling and potential mechanisms of action related to recruitment and differentiation of oligodendrocyte progenitor cells. These data are compelling and elaborate previously reported data in EAE mice (experimental models for multiple sclerosis) and in traumatic brain injury in rats showing that Tβ4 can effect regeneration of neuronal cells after injury. In this experiment, after an ischemic stroke, neurological function in the rat models was significantly improved, apparently by remyelination of neurological axons (nerve fibers that conduct electrical signals) induced by Tβ4. The fact that Tβ4 helps repair and regenerate tissue after a brain injury strongly correlates with other published data showing Tβ4’s ability to regenerate neuronal and cardiac tissue after ischemic events,” stated Dr. Hynda Kleinman, former head of cell biology at the National Institute of Dental and Craniofacial Research, NIH, and a consultant to RegeneRx.

About Tβ4

Tβ4 is a synthetic version of a naturally occurring peptide present in virtually all human cells. It is a first-in-class multi-functional molecule that has been shown in pre-clinical studies to promote endothelial cell differentiation and migration in the heart and central nervous system, promote angiogenesis in dermal and cardiac tissues, increase keratinocyte migration and collagen deposition, and decrease inflammation by down-regulating inflammatory cytokines. RegeneRx has identified several molecular variations of Tβ4 that may affect the aging of skin, among other properties, and could be important candidates as active ingredients in pharmaceutical and consumer products. Researchers at the National Institutes of Health and various academic researchers throughout the world have published numerous scientific articles in high impact journals indicating Tβ4’s in vitro and in vivo efficacy in accelerating wound healing and tissue protection and regeneration under a variety of conditions. Abstracts of scientific papers related to Tβ4’s mechanisms of action can be viewed at www.regenerx.com.

About RegeneRx Biopharmaceuticals, Inc.

RegeneRx is focused on the development of a novel therapeutic peptide, Thymosin beta 4, or Tβ4, for tissue and organ protection, repair and regeneration. Currently RegeneRx has three products in clinical development. RGN-352 is an injectable formulation to treat cardiovascular and central nervous system diseases, as well as other medical indications. RegeneRx has successfully completed a Phase 1 clinical trial with RGN-352. RGN-259 is a sterile, preservative-free topical eye drop for ophthalmic indications. RegeneRx is currently supporting a physician-sponsored Phase 2 dry eye study evaluating RGN-259. RGN-137, a topical gel formulation, is currently being evaluated by RegeneRx in a Phase 2 clinical trial for the treatment of epidermolysis bullosa. Other potential uses for RGN-137 include the treatment of chronic dermal wounds and reduction of scar tissue. Based on strong efficacy data in pre-clinical studies, RegeneRx is initially targeting RGN-352 for the treatment of patients who have suffered an acute myocardial infarction, or heart attack. In addition to this indication, recent pre-clinical efficacy data suggests that RGN-352 may also benefit patients with multiple sclerosis and stroke. RegeneRx also has a preclinical product candidate, RGN-457, which is an inhaled formulation targeting cystic fibrosis and other pulmonary diseases. In addition to the four pharmaceutical product candidates described above, RegeneRx is pursuing the commercial development of peptide fragments of Tβ4 for potential cosmeceutical use. RegeneRx holds 75 issued patents and has 261 patent applications pending worldwide related to its products and holds an exclusive worldwide license for Tβ4 from the National Institutes of Health.

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