A Canadian study of the use of poly-L-lactic acid dermal implant for the treatment of hill and valley acne scarring.

BACKGROUND Hill and valley scarring is 1 of 3 atrophic scar types that occur as a result of acne, becoming more apparent with facial skin aging. Treatment includes resurfacing techniques and the use of injectable fillers. Poly-L-lactic acid is an injectable collagen builder that has been used for the treatment of HIV-associated lipodystrophy and cosmetic enhancement. OBJECTIVE To determine the degree of correction attainable with poly-L-lactic acid and safety findings for the treatment of hill and valley acne scarring. MATERIALS AND METHODS Poly-L-lactic acid was injected over 3 to 4 serial treatments at 4-week intervals in 22 subjects in this single-arm, unblinded, open-label Phase II study. Efficacy was determined by physician, blinded evaluator, and subject assessment of scar improvement using Likert scales, comparing photographs taken by 3 camera systems at treatment visits 2 to 4 and follow-up to baseline. Subjects also assessed treatment satisfaction. RESULTS Percentage of patients with much to excellent improvement using the most sensitive camera system (VISIA-CR) ranged from 45.5% to 68.2%. Subject treatment satisfaction scores increased by 44%. One patient experienced a palpable nonvisible nodule. No subjects discontinued treatment. CONCLUSION Injectable poly-L-lactic acid facilitated improvement in hill and valley acne scarring and was well tolerated.