RegeneRx Biopharmaceuticals, Inc announced the outcome of its phase-II clinical trial evaluating the safety and wound-healing efficacy of RGN-137 for the treatment of patients with chronic pressure ulcers. RGN-137 is a topical gel formulation of thymosin beta 4 peptide (T?4).
The drug candidate was found to be safe and well-tolerated at all three dose levels, with no drug-related serious adverse events, which was the primary objective of the study. Regarding the secondary objective of the study, there were no statistically significant differences observed for complete wound healing or the rate of wound healing between the placebo group and any of the three RGN-137 dose levels. The mid-dose level of RGN-137 was observed to offer more rapid initiation of wound healing when compared to placebo, although this improvement was not statistically significant.
Fifteen US clinical sites enrolled seventy-two patients in a phase-II pressure ulcer clinical trial to evaluate the safety, tolerability, and wound healing effectiveness of three different T?4 concentrations (0.01%, 0.02%, and 0.1%) vs placebo, applied topically, once daily for up to 84 consecutive days. Trial subjects were 19 to 85 years of age and had at least one stable Stage III or IV pressure ulcer with a surface area between 5 and 70 cm. Stage III and IV pressure ulcers are full thickness wounds that penetrate through the skin and muscle, sometimes completely to the bone.
"While we are pleased that we met the primary objective of this pressure ulcer trial indicating no safety issues with RGN-137 in pressure ulcer patients, we had hoped to see an increased incidence of complete wound closure over the 84-day treatment course comparing our drug candidate to placebo. We will continue to analyze the data and will make a decision on future development of RGN-137 for pressure ulcers after we review data from the pending phase-II venous stasis trial," stated J J Finkelstein, RegeneRx's president and chief executive officer. In addition to the pressure ulcer and venous stasis trials, RegeneRx is also presently evaluating RGN-137 in a phase-II clinical trial in patients with epidermolysis bullosa (EB).
"We continue to believe that RGN-137 can be effective in dermal wound healing. It is important to note that all skin ulcers are not the same. Venous stasis ulcers differ from pressure ulcers as they result from venous insufficiency rather than from constant pressure or shearing factors. Likewise, patients with the more serious types of EB (dystrophic and junctional) have wounds that result from genetic factors, leading to a deficiency in collagen VII and an adhesive protein called laminin-5. T?4 has been shown to accelerate collagen deposition and promote laminin-5 expression in laboratory animal models. Both of these types of wounds are superficial compared to Stage III or IV pressure ulcers," commented David Crockford, RegeneRx's vice president of clinical and regulatory affairs. RegeneRx expects data to be reported for the venous stasis trial this quarter and for the EB trial in late 2009.
RegeneRx is focused on the discovery and development of novel peptides to accelerate tissue and organ repair.