Researchers Report that Thymosin beta 4 Improves Neurological Function after Stroke

ROCKVILLE, Md.--(BUSINESS WIRE)--

REGENERX BIOPHARMACEUTICALS, INC. (NYSE Alternext US: RGN) announced that a research team from the Henry Ford Hospital in Detroit, MI reported that Thymosin beta 4 (Tβ4), administered to rats one day after embolic stroke, improved neurological functional outcome compared to control animals. Improvement in neurological function was measured at various time intervals over a seven week period and was statistically significant.

An increase in remyelination of axons (regeneration of the nerve sheath) was observed in rats receiving Tβ4 compared to control animals, likely due to an increased mobilization of oligodendrocyte progenitors (stem cells surrounding axons) that differentiate into mature myelin-producing oligodendrocytes. In cell culture, Tβ4 treated neuronal progenitor cells isolated from normal and stroke rats demonstrated increased mRNA levels of epidermal growth factor receptor. This receptor has previously been shown to be a regulator of oligoprogenitor cell expansion and tissue regeneration in response to brain injury and further supports the role of Tβ4 in stem cell-mediated tissue repair.

“These data are compelling and are consistent with previously reported data in EAE mice (experimental models for multiple sclerosis) showing that Tβ4 stimulates oligoprogenitor cells after injury. In this recent experiment, after an ischemic stroke, neurological function in the rat models was significantly improved, apparently by remyelination of neuronal axons induced by Tβ4. The fact that Tβ4 helps repair and regenerate tissue after a brain injury is not only remarkable, but strongly correlates with data previously published showing Tβ4’s ability to regenerate cardiac tissue after an ischemic event,” stated Dr. Hynda Kleinman, chief of the Cell Biology Section at the National Institute of Dental and Craniofacial Research, NIH, and a consultant to RegeneRx.

“We are very pleased with these results, which provide a foundation to further explore Tβ4 as a treatment for neurological injury,” commented Daniel C. Morris, MD, senior staff physician, Department of Emergency Medicine, Henry Ford Health Systems.

The research was presented by Dr. Morris, representing the Departments of Neurology and Emergency Medicine, Henry Ford Health System, Detroit, MI, at the International Stroke Conference, San Antonio, TX, February 23-26, 2010. The research was performed under a Material Transfer Agreement between RegeneRx Biopharmaceuticals, Inc. and the Henry Ford Health System.

About RegeneRx Biopharmaceuticals, Inc.

RegeneRx is focused on the discovery and development of novel peptides to accelerate tissue and organ repair. Currently, RegeneRx is developing three product candidates, RGN-137, RGN-259 and RGN-352 for dermal, ophthalmic, and cardiovascular tissue repair, respectively. These product candidates are based on Tβ4, a synthetic copy of a 43-amino acid, naturally occurring peptide, in part, under an exclusive world-wide license from the National Institutes of Health. RegeneRx holds over 60 world-wide patents and patent applications related to novel peptides. It is currently in Phase 2 clinical development for dermal and ophthalmic wound healing and has now completed a Phase 1 clinical trial supporting delivery of RGN-352 for acute cardiovascular and other indications requiring systemic administration. RegeneRx is also developing novel peptides for the cosmeceutical industry based on its experience with Tβ4 and its biological activities in the skin. It is currently in Phase 2 clinical development for dermal and ophthalmic wound healing and has now completed a Phase 1 clinical trial supporting delivery of RGN-352 for acute cardiovascular and other indications requiring systemic administration. RegeneRx is also developing novel peptides for the cosmeceutical industry based on its experience with Tβ4 and its biological activities in the skin.

RegeneRx Technology Background

Tβ4 is a synthetic version of a naturally occurring peptide present in virtually all human cells. It is a first-in-class, multi-faceted molecule that promotes endothelial cell differentiation, angiogenesis in dermal tissues, keratinocyte migration, and collagen deposition, while down-regulating inflammation. 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 at other academic institutions throughout the world, have published numerous scientific articles indicating Tβ4’s in vitro and in vivo efficacy in accelerating wound healing and tissue protection under a variety of conditions. Abstracts of scientific papers related to Tβ4’s mechanisms of action may be viewed at RegeneRx’s web page: www.regenerx.com.

Forward-Looking Statements

Any statements in this press release that are not historical facts are forward-looking statements made under the provisions of The Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the words “project,” “believe,” “anticipate,” “plan,” “expect,” “estimate,” “intend,” “should,” “would,” “could,” “will,” ”may” or other similar expressions and include statements regarding the safety and efficacy of RGN-137, RGN-259, RGN-352 and Tβ4 fragments. Further, the research described herein regarding Tβ4’s effect in stoke models may not prove to be beneficial or may not result in any commercial or profitable products. One should consider important factors described in the Company’s filings with the Securities and Exchange Commission (“SEC”), including those identified in the "Risk Factors" sections of the annual report on Form 10-K for the year ended December 31, 2008 and such other items described in the filed Company’s quarterly report on Form 10-Q for the fiscal quarter ended September 30, 2009 or other filings it makes with the SEC. Any forward-looking statements in this press release represent the Company’s views only as of the date of this release and should not be relied upon as representing its views as of any subsequent date. The Company anticipates that subsequent events and developments may cause its views to change, and the Company specifically disclaims any obligation to update this information, as a result of future events or otherwise, except as required by applicable law.