Multicenter clinical trial on the performance and tolerability of the Hyaluronic acid-collagenase ointment for the treatment of chronic venous ulcers: a preliminary pilot study.

BACKGROUND: Bed debride - ment is important to treat chronic wounds. Effec - tive agents should remove the necrosis but pro - tect the granulation tissue. We evaluated the per - formance and tolerability of a new composite ointment containing collagenase and hyaluronic acid for chronic venous ulcers. PATIENTS AND METHODS: Subjects with class 6 venous ulcers (CEAP classification) of at least 6 months duration were prospectively recruited. The ointment was administered daily and follow-up visits were conducted on the fifth, 10 th , 15 th and 20 th days. On each visit the necrotic area was measured with a grid. The moisture balance, odour, viability of non- necrotic areas and the presence of erythema were also assessed. Primary outcome was the percentage of subjects with complete debride - ment, secondary outcomes the time to com - plete healing, reduction of the lesion area, ab - sence of necrotic tissue, presence of odor, ery - thema, hydration, any adverse events. RESULTS: One hundred subjects were en - rolled in four centres. All patients achieved com - plete debridement of the necrotic area and a sig - nificant reduction of the total ulcer area by day 20, while other parameters improved significant - ly over time. Only two patients experienced a transient leg oedema. CONCLUSIONS: The combination of collage - nase and hyaluronic acid is safe and effective for chronic venous ulcers.