Cosmetic dermatology - New toxins under development

By Louise Gagnon – Correspondent, The Chronicle

Researchers investigating PRP as a potential therapy for the treatment of androgenic alopecia

New neurotoxins, a new filler, a new possible cellulite treatment, date to support the use of platelet-rich plasma (PRP) to manage androgenetic alopecia, and off-the-face use of fillers are all innovations in cosmetic dermatology that Canadian dermatologists are studying and investigating.

The newest toxin that will join the array of neuromodulators now available in Canada is prabotulinumtoxin-A.

“It will be interesting to see where it will fit in the (neurotoxin) landscape,” said Dr. Lisa Kellett, a dermatologist and medical director in Toronto at DLK on Avenue.

Dr. Vince Bertucci, a dermatologist and medical director of Bertucci MedSpa in Woodbridge, Ont., was involved in clinical trials of his emerging neurotoxin.  “In a clinical trial comparing it to onabotulinumtoxinA that was carried out at sites in Canada and Europe, it seemed to give similar results. It remains to be seen how it performs in real world circumstances,” he said.

Still another potential addition to the neurotoxin market is daxi-botulinum toxin, which recently completed Phase III trials.  “It has the same 150 kDa active protein, but one of the things that distinguishes it from other neurotoxins is the presence of an excipient peptide,” explained Dr. Bertucci.  “The theory is that the peptide’s positive charge causes it to stay resident at the neuromuscular junction for a longer period of time, thus enhancing longevity of effect.”

Another potential neurotoxin is EB-001A, a novel botulinum neurotoxin serotype E that, in early studies for the treatment of glabellar frown lines, differentiates itself with its rapid onset of action and shorter duration of effect, according to Dr. Bertucci.

Potential gateway neurotoxin?

“This may serve as an entry-leven neurotoxin for individuals hesitant to get treated,” he said.  “It could potentially be a gateway neuromodulator before patients commit to standard neuromodulators. Other uses are also being contemplated.”

And still other neuromodulators that are early in the investigational path may eventually enter the marketplace.  These liquid neuromodulators would offer the advantage of not requiring reconstitution, noted Dr. Bertucci.  “They can be used straight out of the vial,” he said.  “This might simplify the treatment process, making it more efficient.”

A possible new management strategy for cellulite is the use of collagenase clostridum histolyticum (CCH), to target the collagen-rich subdermal septae which contribute to the appearance of cellulite, noted Dr. Sonya Cook, a Toronto dermatologist and co-founder of Compass Dermatology.

Data from Phase II research from a randomized, clinical trial involving 375 women who were assigned to treatment or placebo to manage edematous fibrosclerotic panniculopathy of the buttocks or posterolateral thighs supported the use of CCH to improve appearance (Dermal Surg 2019 Feb 28).  Moreover, some positive Phase III data has been published in media release.

“The safety profile looks excellent,” said Dr. Cook in an interview with THE CHRONICLE OF SKIN & ALLERGY.  “It could be a really great addition to our body armamentarium.  The question if whether it will be long-lasting, which is the question with a lot of cellulite treatments.  It is targeting the cause of cellulite by dissolving the cutaneous ligaments that tether the muscle and the skin together, which is why you get the out-pouching of fat.  It will work similar to Cellfina, but it is a chemical approach.”

Other approaches to improve the appearance of the buttocks include the injection of fillers such as Sculptra.

“Sculptra stimulates collagen production and improves the quality of the skin,” said Dr. Cook.  “When injecting Sculptra, you are also breaking up the collagen tethers, resulting in a smoother appearance in the injected area.

Dr. Kellett noted that she is using Sculptra for body contouring of the buttocks to “fill in defects and to treat cellulite as well.”

When treating the buttocks, clinicians need to proceed with caution, warned Dr. Cook. “There are large vascular structures present,” said Dr. Cook.  “You need to know the anatomy.”

New filler versions introduced

A new filler that clinicians can look forward to incorporating in their practices is Juvedérm’s Volux, a hyaluronic acid using Vycross technology that includes lidocaine for patient comfort, noted Dr. Cook.  “It is being marketed for the chin and jaw lines,” she said, pointing out clinical data suggest facial definition can last anywhere from 18 to 24 months. “It provides long-lasting contouring.”

Another innovation for facial rejuvenation is the Silhouette InstaLift threads, which are composed of poly-L-lactic acid (PLLA) and polyglycolide/L-lactide (PLGA) dissolving sutures.  The threads lift tissue in the mid-face and jawline, stimulate collagen, and add volume.  It is approved in the U.S., but not yet north of the border. “We are looking forward to adding this to our practice once it is approved in Canada,” said Dr. Cook.

Increasingly, platelet-rich plasma (PRP) is being used to treat hair loss, noted Dr. Cook.  Indeed, published research is suggesting that PRP can be used as a therapy when traditional options such as minoxidil are not effective in treating androgenetic alopecia (Int J Trichology 2019 Mar-Apr; 11(2);68-79).

“We are using PRP for both skin rejuvenation and androgenetic alopecia,” noted Dr. Kellett.