Evaluation of Hylan B (Hylan Gel) as Soft Tissue Dermal Implants

Abstract

AbstractHylan B gel is a viscoelastic insoluble crosslinked derivative of the natural hyaluronan (hyaluronic acid, HA) polymer. Hyaluronan derivatives such as hylan B have enhanced rheological properties and possess the desired biological properties of natural hyaluronan. Hylan B was evaluated in nonclinical in vivo studies for biocompatibility and residence times in dermal tissues. In one study, residence time of radiolabeled [14C]-hylan B was evaluated in guinea pigs following intradermal administration with serial sacrifice (0, 1, 4, 12, 24 weeks). Analysis of radioactivity revealed that at 6 months post-implantation up to 98% of the radioactivity was recovered from the specific injection site (mean 76.7± 29.4%). A half-life time of 12.2 months was estimated from analysis of the data. In another study, the behavior of hylan B gel implanted in the intradermal and subcutaneous tissue of guinea pigs was evaluated at 3 days and at 1, 2, 4, 9, 13, 26 and 52 weeks. In this study, collagen implants were evaluated in parallel with hylan B gel implants in the same animals. Hylan B gel was found to be biologically compatible and stable in the dermal tissue. At one year post-implantation, hylan B gel was detected in a majority (12/16) of test sites. None of the collagen implant materials was detected at one year post-implantation.