REGENERX BIOPHARMACEUTICALS, INC. (NYSE Amex:RGN) today reported on several clinical studies with Thymosin beta 4 (Tβ4) presented the Second International Symposium on Thymosins in Health and Disease, in Catania, Italy. The following are synopses of the presentations:
Myocardial Development of RGN-352 (Injectable Tβ4 Peptide)
David Crockford, RegeneRx’s vice president for clinical and regulatory affairs presented an overview of the biological properties that support Tβ4’s near term and long term clinical applications. Mr. Crockford noted that special emphasis is being placed on the development of RGN-352 for the systemic (injectable) treatment of patients with ST-elevation myocardial infarction (STEMI) in combination with percutaneous coronary intervention, the current standard of care in most western countries for this common type of heart attack. The goal with RGN-352 is to prevent or repair continued damage to cardiac tissue post-heart attack, when such tissue around the damaged site remains at risk.
Dr. Dennis Ruff, vice president and medical director of ICON, and principal investigator, presented the most current results on the Phase I safety study with RGN-352 entitled, “A Randomized, Double-blind, Placebo-controlled, Dose-response Phase I Study of the Safety and Tolerability of the Intravenous Administration of Thymosin Beta 4 and its Pharmacokinetics After Single and Multiple Doses in Healthy Volunteers.” Dr. Ruff discussed key aspects of the study and concluded with, “There were no dose limiting or serious adverse events throughout the dosing period. Synthetic Tβ4 administered intravenously up to 1260 mg, and for up to 14 days, appears to be well tolerated with low incidence of adverse events and no evidence of serious adverse events.”
Ophthalmic Development of RGN-259 (Sterile Tβ4 Eye Drop)
Dr. Steven Dunn, a corneal specialist at Detroit Medical Center, and his colleagues, presented encouraging wound-healing data from a compassionate use clinical trial evaluating the efficacy of RGN-259 (sterile Tβ4 eye drops) in the management of chronic non-healing corneal ulcers caused by the herpes zoster virus. He reported on four patients who ranged in age from 47-84, all of whom had non-healing ulcers of six weeks or longer. The patients were monitored for ulcer size, depth, associated vascularization and comfort during a 28 day treatment period and for 30 days thereafter. “All ulcers (from 0.05 to 12.6 mm2) showed a significant reduction in size during the 28 day treatment period with two ulcers being healed completely at 58 days and the remaining measuring 0.3 mm2 and 0.1 mm2. No progressive stromal thinning was seen and there was reduced associated ocular irritation,” according to Dr. Dunn.
Dermal Wound Healing with RGN-137 (Topical Tβ4 Peptide)
Dr. G. Guarnera, Department of Vascular Surgery and Pathology, Instituto Dermopatico dell’Immacolata, Rome, Italy, reported on, “The Effect of Thymosin Beta 4 Treatment of Venous Stasis Ulcers (Answers from a Well-Controlled European Clinical Trial).” Dr. Guarnera described the Phase II, 73 patient dose-finding trial that was conducted at eight hospitals in Italy and Poland. He reported that all doses of Tβ4 were well-tolerated with adverse events distributed evenly over the placebo and active treatment groups. In evaluating incidence of healing at day 84 (last study day) and time to healing, the mid-dose Tβ4 group had a 33.3 percent response rate compared to 23.5 percent in the placebo group, and the mid-dose Tβ4 group decreased the median time to healing by 45 percent among all groups. It was reported that the incidence of healing among all groups was shown to decrease with the increase of baseline ulcer area and a longer healing time was associated with larger lesions. “Efficacy findings from this Phase II study suggest that a Tβ4 dose of 0.03 percent may have the potential to accelerate wound healing and that complete wound healing can be achieved within 3 months in about 25 percent of the patients, especially among those whose wounds are small to moderate in size or severity,” according to Dr. Guarnera.
Dr. Jo-David Fine, Professor of Medicine and Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, provided an update on a Phase II clinical trial of topically administered RGN-137 for wound healing in inherited epidermolysis bullosa (EB). Dr. Fine reviewed the study parameters and enrollment, which remains blinded to both patients and investigators. He highlighted a notable experience with one enrollee that he personally treated as follows:
“This was in a young woman with severe generalized recessive, dystrophic EB who had been followed by our group for nearly 25 years. Prior to enrollment in this study, her skin wounds invariably took months to even partially heal. Within less than two weeks of initiation of therapy in our study, the test site (her treated wound) completely re-epithelialized (as opposed to other non-treated areas) and did not subsequently break down, as has been the case with other skin wounds arising in this patient. …her remarkably surprising experience gives encouragement to the potential clinical value of this agent, when applied topically, in patients with inherited EB,” remarked Dr. Fine.
“Today’s clinical presentations were informative and provide encouraging follow-up to previous clinical reports. We heard about an EB patient (with a 25% chance of receiving placebo) where healing was completely different, i.e., quicker and more durable, than had been the case for the past 25 years according to her physician. This healing and scarring process appears similar to published and unpublished reports of the regulation of scarring in the heart, kidney, liver, and skin by Tβ4 and its derivatives,” stated J.J. Finkelstein, RegeneRx’s president and chief executive officer. He continued, “Dr. Guarnera’s data in the venous stasis trial were also important as they suggest that RGN-137 could potentially be useful to accelerate wound healing in patients with less severe or smaller venous stasis ulcers. Finally, the improved wound healing in neurotrophic corneal ulcer patients, reported by Dr. Dunn, is consistent with previously published animal studies showing accelerated wound healing in the eye. It is important to note that, to date, in all clinical studies with RegeneRx’s drug candidates, Tβ4 was found to be safe and well tolerated.”