Use of poly-L-lactic acid facial filler appears to be well tolerated and effective at facilitating improvement for the treatment of hill and valley acne scarring, according to a Canadian single-arm, unblinded, open-label medical device Phase II study.
“As we age, we loose collagen and as a result acne scarring actually becomes more apparent. Unfortunately with acne scarring treatment you can never get it 100 per cent better, but for most patients any improvement is good,” said Dr. Sheetal Sapra, a dermatologist in Oakville, Ont., and lead author of the paper, which was published in Dermatologic Surgery (May 2015; 41(5):587–594).
“If you look at what you can do to treat hill and valley acne scarring there is no cream that really helps. Chemical peels can help a little but there are a lot of side effects,” said Dr. Sapra, founding editor of The Chronicle of Cosmetic Medicine + Surgery.
Typically, treating physicians have used lasers for resurfacing or micro-needling for the treatment of hill and valley acne scarring. Both treatments cause damage to the epidermis and dermis, stimulating neocollagenesis, said Dr. Sapra.
“So we decided that we wanted to try to produce collagen in a different way by injecting poly-L-lactic acid into the skin,” he said.
Poly-L-lactic acid was first approved in Canada in June 2006 and is widely used for cosmetic enhancement in addition to treating HIV-associated facial fat loss, the indication for which it was originally approved, the authors reported.
According to the authors, the primary objective of this single-site study, which began in Oct. 2008 and was completed in Sept. 2009, was to evaluate the degree of correction achievable with injectable poly-L-lactic acid for the correction of hill and valley scarring over a period of six months.
During the course of the investigation, the trialists also wanted to assess the safety and efficacy of using poly-L-lactic acid for the treatment of hill and valley scarring associated with acne, said Dr. Sapra.
A total of 22 of the planned 25 subjects participated in this study. The mean age of the study population was 37.6 years with a 9:13 male-to-female ratio. Nearly two-thirds of the study population were Caucasian, the authors reported.
At the screening visit (Visit 1), patients received a thorough review of medical history, a review of previous and current medications, a physical examination, and baseline photography. According to the authors, photography was performed using three camera systems including the VISIA-CR system, a handheld Canon SLR, and a Fuji S2 camera.
During the investigation the participants received their first treatment with poly-L-lactic acid approximately two weeks after the screening visit (Session 1). Follow-up treatments (Session 2, 3 and 4) occurred at intervals of no less than four weeks if the study investigator deemed that additional treatments were necessary, the authors wrote.
Dr. Sapra and his colleagues reported that poly-L-lactic acid was reconstituted before use with sterile water for injection. They also noted that there were two dilutions used.
In addition, the authors noted that the study investigator also had the discretion to add lidocaine-epinephrine directly to the reconstituted solution and/or use topical lidocaine-prilocaine prior to administration.
Poly-1 -lactic acid improved scarring
The efficacy parameters recorded during the study included a physician scar improvement scale (PSIS), a blinded evaluator scar improvement scale (BESIS), a self-assessed scar improvement scale (SASIS), and a subject treatment satisfaction score (STSS) at sessions 2 to 4 and at the follow-up visit.
Overall, the authors reported that the use of poly-L-lactic acid for the treatment of hill and valley acne scarring was associated with improvement in scarring as determined by the PSIS, BESIS, and SASIS assessment scale scores. The mean scores for all three scales (PSIS, BESIS, and SASIS) decreased from Session 2 to the follow-up visit, indicating improvement in scarring.
Dr. Sapra and his colleagues also reported that the greatest improvement in scarring was noted by the blinded evaluator, where there was determined to be a 40.5% improvement in scores with images taken by the VISIA-CR camera system. The greatest improvement in scores by physicians and subjects was also observed in images taken by the VISIA-CR system, at 29.4% each.
In terms of safety, the authors reported that during the study period eight patients (36.4%) experienced a treatment-emergent adverse event, the authors noted. They added that one subject experienced a palpable nonvisible nodule <0.5 cm that appeared at one day after a treatment session. This nodule, according to the authors, did not require supportive treatment and was deemed to be possibly treatment related.
Advantages, disadvantages of poly-L-lactic acid
“I think the big advantage to using poly-L-lactic acid is that little or no downtime is needed,” said Dr. Sapra, who added that there are also few to no side effects associated with it.
“The other advantage of using poly-L-lactic acid as a treatment is that it works well for treating skin of colour patients—you are not going to get the same pigmentation change that you get from using a laser.”
The main disadvantage of using poly-L-lactic acid as a treatment is that repeated treatment is needed and it also has to be maintained, noted Dr. Sapra.
“When poly-L-lactic acid is used properly it really has few side effects. I encourage people to use it in combination with other cosmetic treatments. Where I am seeing the most improvement is when poly-L-lactic acid is used in combination with a laser treatment. Patients are really getting a wow effect and I am really happy about that,” Dr. Sapra concluded.