RegeneRx's TB4 May Repair Damage to Aging Skin; Scientist Reports on Research at 5th International Symposium on Aging Skin.

Business Editors & Health/Medical Writers

BIOWIRE2K

SAN DIEGO--(BW HealthWire)--May 21, 2001

Thymosin Beta 4 (TB4), a relatively unknown molecule despite its widespread presence throughout the body, may be valuable in repairing skin damage caused by the sun or even by the wear-and-tear of the aging process itself through its regulation of the cell-building protein, actin.

This is the essence of a report presented by Dr. Allan L. Goldstein at the 5th Annual International Symposium on Aging Skin, held at the Loew's Coronado Bay Resorts in Coronado, CA.

Dr. Goldstein, Professor and Chairman of the Department of Biochemistry and Molecular Biology at The George Washington University Medical School, Washington, D.C. - also the founder of RegeneRx Biopharmaceuticals, Inc. - reported on recent collaborative studies with Dr. Hynda Kleinman and her colleagues at the National Institutes of Health (NIH) who found that TB4 significantly improved healing in dermatological and corneal wounds in experimental animals.

According to Dr. Goldstein, "Many of the same biological events associated with wounds and other skin damage are also involved in the aging process of skin. Environmental factors such as ultra-violet radiation from the sun or other injuries to keratinocytes (skin cells) associated with the aging process may be reparable with TB4, similar to its wound repair activity already identified and previously reported."

Recently, a number of other reports have been published by independent researchers on TB4. For example, Drs. Daniel Safer and Vivian Nachmias (University of Pennsylvania) have found that TB4 is the major actin sequestering peptide in normal mammalian cells, thus is critical to the process that allows cells in all tissues, when injured and damaged, to remodel and heal.

In laboratory studies conducted at the NIH by Dr. Hynda Kleinman and her colleagues, TB4 has been found to accelerate wound healing as well angiogenesis (formation of new blood vessels) in a variety of in vitro and in vivo models.

Additional studies have shown that TB4 accelerates wound healing, sequesters actin and down-regulates specific inflammatory cytokines such as Interleukin-1, Interleukin-6 and tumor necrosis factor. Most recently, Dr. Gabriel Sosne, now at the Henry Ford Hospital in Detroit, reported that TB4 is similarly effective in reducing inflammation and accelerating healing of the injured eye in experimental rodent models. "Clearly," said Dr. Goldstein, "we continue to see a common biological activity throughout these independent studies of TB4 which we believe should be applicable to humans as well."

Dr. Goldstein also emphasized the central functions of the skin, which is the body's largest immune organ. The component cells of the multi-layered skin - dendritic cells, keratinocytes, monocytes, and nerve cells - produce and process a host of biologically active cytokines, chemokines, and growth factors that enable them to fight off microorganisms and repair damage and injury.

Producing its own protective antigens and immune factors while recognizing enemy antigens, the skin maintains complex communications with the rest of the immune system, signaling it for action when necessary. Like other components of the body's dynamic defense-and-repair system, the skin's capabilities decline with age; it becomes less able to combat immune challenges and other chronic insults such as chemicals and ultraviolet radiation.

TB4 is a 43 amino acid peptide which exhibits a number of physiological properties not seen with other wound healing drugs and growth factors under development. The actions include the ability of TB4 to sequester and regulate actin - a protein needed to form the cytoskeleton and maintain the structure of the skin and facilitate its repair - as well as by stimulating angiogenesis and reducing inflammation, all of which play important roles in wound healing and the remodeling process of damaged skin.

RegeneRx Biopharmaceuticals, Inc. (OTCBB:RGRX), is a development stage biopharmaceutical company focusing on products to treat a variety of human diseases. The company is completing pre-clinical work related to TB4 prior to filing an IND scheduled for later this year or early 2002.

The information in this press release may include certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995.

These statements concern the Company's current expectations regarding future events, including the ongoing and prospective development and commercialization of TB4 and possible future benefits to the Company, its shareholders, and patients.

Due to the nature of product development and the regulatory approval process, the forward-looking statements contained in this press release are subject to risks and uncertainties, including those reflected in the Company's filings with the Securities and Exchange Commission, particularly its Annual Report on Form 10-KSB for the year ended December 31, 2000.

The Company assumes no obligation to update or revise any forward-looking statements made herein or any other forward-looking statements made by the Company.