Efficacy and tolerance of an injectable medical device containing stable hybrid cooperative complexes of high- and low-molecular-weight hyaluronic acid: a monocentric 16 weeks open-label evaluation

BACKGROUND: An injectable medical device containing stable hybrid cooperative complexes of high- and low-molecular-weight hyaluronic acid (HA) has been developed with characteristics suited for a global improvement of facial esthetics. OBJECTIVE: To evaluate the HA product performance in improving some key facial esthetic features. The study employed clinical scales, subjective evaluations, and facial skin objective measurements. METHODS: A single Italian site treated 64 female subjects aged 38–60 years, with injections at five predetermined points, on each side of the face, with a 4-week time lapse between the first and the second product administration. Subjects were evaluated after 4, 8, 12, and 16 weeks, using validated clinical scales, subjective evaluation, and objective quantitative outcome measures. Assessment of esthetic results included photographic documentation. RESULTS: Both the clinical and subjective assessments, and the majority of objective instrumental parameters indicated an improvement throughout the study and were already significant at week 4 or 8 and were still significant at week 16 (3 months after the second treatment). Minor and temporary local skin reactions were observed in 23% of subjects at the site of the injections, and the global judgment on tolerability was good or excellent, both in the investigators’ opinion and volunteers’ self-evaluation. CONCLUSION: Both subjective and objective improvement of the facial parameters was consistent with the bio-remodeling purpose, and persistent and still statistically significant at the end of the study. The tolerability and safety profile of the product were judged good or excellent both by investigators and volunteers. This study supports the claim for bio-remodeling of these stable hybrid cooperative complexes of low- and high-molecular-weight HA.