Study highlights longevity of smooth-gel, non-animal hyaluronic acid fillers

March 1, 2008

Results from a repeat treatment study highlight the persistence of the benefits provided by the family of smooth-gel hyaluronic acid fillers (Juvéderm, Allergan) for correction of nasolabial folds. The retreatment was administered within 24 to 36 weeks after the last initial treatment. It required significantly less filler volume than originally, and after 24 weeks, was associated with clinically significant improvement exceeding that achieved originally.

Key Points

San Diego - Results of a study evaluating repeat treatment of nasolabial folds with the smooth-gel, non-animal hyaluronic acid (HA) dermal fillers (Juvéderm, Allergan) confirms these next-generation HA products provide clinically significant, long-lasting correction, says Stacy R. Smith, M.D.

In the repeat treatment study, which was an open-label extension of the pivotal trial, patients were injected with the same HA filler (J30, J24HV or J30HV) they were originally assigned.

The treatment was administered 24 to 36 weeks after the last injection was given in the pivotal trial (mean 29 weeks) and was performed to achieve a target of full correction.

"The outcomes recorded in this study corroborate what physicians using Juvéderm have already witnessed in their practices, and that is this unique family of HA fillers provides excellent and durable results. Less filler was needed at six to nine months and more benefit was observed 24 weeks later because these patients still retained benefit from their initial injections," says Dr. Smith, study investigator and president, Therapeutics Clinical Research, San Diego.

"Of the currently approved HA fillers, this family of smooth-gel products represents the later and greater technology that provides more persistent correction. This line of HA fillers contains a higher concentration of HA and has greater HA cross-linking, which is widely believed to contribute to longevity.

"In addition, they are manufactured with proprietary technology (Hylacross), resulting in material that flows easily when injected and provides smooth, natural-appearing results," Dr. Smith tells Dermatology Times.

Pivotal study

The pivotal study compared the smooth-gel HA fillers with cross-linked bovine collagen (Zyplast).

It enrolled 439 patients who were randomized to receive one of the three HA fillers in one nasolabial fold and bovine collagen on the contralateral side. Up to two touch-ups were allowed over the first four weeks to achieve optimal correction.

At 24 weeks, the results showed the HA filler treatment resulted in better and longer-lasting correction than the bovine collagen.

Across the three treatment groups, between 78 percent and 88 percent of patients indicated a preference for the HA filler based on assessment of the treatment effects.

The repeat study was performed at a subset of the original investigational sites and included patients who indicated a preference for the HA filler over bovine collagen and who were interested in receiving a repeat treatment within 24 to 36 weeks of their last injection in the pivotal trial.

The repeat treatment was administered into both nasolabial folds, using the same HA filler product the patient received in the pivotal trial.

A total of 80 subjects were enrolled in the repeat treatment study. They had a mean age of 50 years; 89 percent were female; 37 percent were non-Caucasian; 73 percent were Fitzpatrick skin types II-IV; and 24 percent were Fitzpatrick skin types V-VI.

"The majority of pivotal trial patients who participated in the extension study wanted to wait as long as possible before being retreated. They often stated that they were still satisfied with the benefit they maintained from their initial treatment and wanted to further prolong the results by delaying their retreatment as much as allowed within the study protocol," says Dr. Smith, assistant clinical professor, division of dermatology, University of California, San Diego.

The safety review showed there were no serious or unanticipated adverse events.

Disclosure: Dr. Smith has been a clinical investigator for other companies marketing dermal fillers and other facial rejuvenation products. He has no direct financial interest in any of those companies.