Castle Creek Pharmaceuticals (CCP) has developed and validated the first Investigator's Global Assessment (IGA) scale to be used by clinicians evaluating the average overall severity of epidermolysis bullosa simplex (EBS) lesions in clinical trials.

The new IGA scale is being presented at the 47^th Annual ESDR Meeting 2017 held at the Salzburg Congress Centre in Salzburg, Austria September 27-30^th, 2017.

The five-point IGA scale for overall clinical assessment defines EBS-involved skin as Clear, Almost Clear, Mild, Moderate, and Severe, based on the presence or absence of blisters and factors including blister size, erosions, crusting and erythema. The IGA scale will be used to evaluate the safety and efficacy of diacerein 1% ointment, an investigational topical being developed by CCP for the treatment of EBS, in the ongoing Phase 2/3 DELIVERS study.

"We have standard instruments in place for evaluating therapies for epidermolysis bullosa in general, but until now no such instrument has been validated for evaluating the severity of EBS lesions specifically," says Alain Hovnanian, MD, PhD, department of genetics at the University Paris Descartes in Paris, France. "This first-of-its-kind IGA scale will serve an important role in advancing clinical research and determining the efficacy of potential therapies for the most common form of epidermolysis bullosa."

Proof of concept results

In a separate presentation that has also been selected for the "Clinical Outcomes 3: Bullous diseases and other entities" poster walk session, Michael Ablinger, MSc, scientific associate at the EB House Austria, will discuss results from a proof-of-concept study evaluating the safety of diacerein 1% ointment topically applied in generalized-severe EBS.

In the study, researchers analyzed the metabolization of diacerein 1 % ointment both in vitro and in vivo. A Franz diffusion cell setup demonstrated complete conversion into rhein within the skin, and bio-transformation into rhein was also observed in patients upon topical application. Treatment of 3 percent of the body surface for four weeks resulted in systemic rhein levels that were approximately 150-fold lower than levels detected 24 hours after single-dose oral intake.

"Our results demonstrate that the prodrug diacerein is converted into its active form rhein within the skin," said Ablinger. "The process allows for an anti-inflammatory effect in the skin of EBS patients."