Filling all the nooks and cranies

Every filler is engineered slightly differently to fulfill the aesthetic needs and challenges of each patient, individually, and the agents in the research pipeline are promising to add more diversity than already provided by those agents currently available. With all of the choices and new technologies, determining what is the best option for any given patient's circumstances can be challenging.

One expert offers a comprehensive review of the spectrum of fillers on the market today, their various uses and indications, and the latest results of the trials under way.

Evolence (ColBar Life Science), not yet approved by the Food and Drug Administration (FDA), is an injectable matrix of highly cross-linked, homogeneous type I atelopeptide porcine collagen.

The matrix forms a three-dimensional gel network that acts as a filler.

"According to interim results of clinical trials under way in Europe, comparing Evolence and Zyplast (Allergan Medical), Evolence produces immediate reductions in wrinkle severity that are equivalent to improvements made with Zyplast. The significant benefit seen with Evolence on wrinkle severity is that the effect lasts much longer than that of Zyplast," says Rhoda S. Narins, M.D., clinical professor of dermatology at NYU Medical Center and director of the Dermatology Surgery and Laser Center in New York.

Dr. Narins tells Dermatology Times that in the European study safety results, negative skin tests were recorded in all patients, and ColBar's Clymatrix collagen found in Evolence demonstrated a low immunogenicity profile. There were no occurrences of edema or ulceration following nasolabial fold injection, and only a "very slight" erythema was seen in both filler-treated sides. In short, Evolence was at least as safe as Zyplast.

In the United States, the FDA phase 3 clinical trial for cosmetic use of Evolence 12-month follow-up for safety and efficacy is almost complete, and results should be available after January 2007. Dr. Narins says a hypersensitivity study, initiated in April 2006, proved the low risk of reaction to porcine collagen implants so that a skin test will probably not be required prior to treatment with Evolence.

In the United States, the FDA pivotal study comparing Evolence and Restylane (Q-Med) was initiated in December 2005 and is currently in phase 3 trials. Dr. Narins says there were no positive reactions in post-skin tests and no significant device-related adverse events observed so far with either product.

Belotero (Merz Pharmaceuticals), not yet FDA-approved, is another filler currently undergoing a phase 3 pivotal trial for cosmetic use in the United States. It is a nonanimal hyaluronic acid having an optimal concentration of sodium hyaluronate (22.5 mg/ml) and utilizing a cohesive polydensified matrix (CPM) technology.

According to Dr. Narins, this provides a cohesive product with variable density for more complete filling. Belotero comes in an ergonomically elegant syringe, making it user-friendly.

Laresse (not yet FDA-approved) is another non-permanent filler consisting of an ultra-smooth, clear gel, manufactured by FzioMed. Dr. Narins says it was just launched on the market in Europe this summer, and a U.S. phase 3 clinical trial is imminent.

"Based on FzioMed's patented science, Laresse boasts well-known, safe, absorbable medical polymers, combining carboxymethylcellulose (CMC) and polyethylene oxide (PEO). It is bioabsorbable, biocompatible and has an excellent safety profile," Dr. Narins claims.

Aquamid (Contura), not FDA- approved, on the other hand, is an injectable polyacrylamide hydrogel (97.5 percent water and 2.5 percent linked polymer), and is a permanent filler. Dr. Narins says that it is homogeneous and biocompatible. It is nonabsorbable, nonbiodegradable, nonallergenic and nonmigrational.

"This filler has immediate, predictable and lasting aesthetic results, with an extensive documented safety profile. It is injected subcutaneously using a fine multi-line technique," Dr. Narins says.