Original articles: ease of wound closure as an endpoint of treatment efficacy

New treatments for chronic wounds require carefully performed clinical trials with significant endpoints. Total wound closure is the only endpoint currently accepted by the Food and Drug Administration. This study describes a scale that measures ease of wound closure and applies it to a four-arm prospectively randomized, blinded pressure ulcer trial of recombinant human platelet-derived growth factor-BB. Following validation of interrater reliability, 83 evaluable subjects' photographs were given a weekly ease of closure score by four raters blinded to treatment. The change of ease of closure score was correlated with the change of wound area and volume. Each ease of closure score was given a procedural cost. Results showed ease of closure did not directly correlate with either wound area or volume, suggesting that it was measuring additional information. The mean change in ease of closure score was 6 for subjects treated with 100 microg recombinant human platelet-derived growth factor-BB daily; 5 for those treated with 300 microg growth factor daily or 100 microg recombinant human platelet-derived growth factor-BB bid; and 4 for those treated with placebo. The cost savings ranged from $7200 for the group receiving 100 microg recombinant human platelet-derived growth factor-BB daily to $6300 for the controls. Outcomes in all 4 groups were significantly improved from their starting evaluation (p < 0.001). Based on this study, ease of closure is a verifiable endpoint that can be related to cost efficiency and may be a measure of efficacy.