A Randomized, Bilateral, Prospective Comparison of Calcium Hydroxylapatite Microspheres versus Human‐Based Collagen for the Correction of Nasolabial Folds

BACKGROUND Current soft tissue fillers are a compromise between ease of use, duration of correction, reactivity, and cost. A product utilizing calcium hydroxylapatite (CaHA) is currently being used as a soft tissue filler. OBJECTIVE The objective was to compare the efficacy and safety of CaHA microspheres versus human-based collagen for the correction of nasolabial folds. MATERIALS AND METHODS Four centers enrolled 117 subjects with moderate to deep nasolabial folds. Subjects received CaHA on one side of the face and human collagen on the other. Up to two touch-ups were allowed. A blinded panel of experts evaluated subject photographs from initial and follow-up visits. RESULTS Seventy-nine percent of subjects had superior improvement on the CaHA side through 6 months (p<.0001). For optimal correction, significantly less volume and fewer injections were needed for CaHA than for collagen (p<.0001). Adverse event rates were comparable, with some increase in bruising and edema for CaHA-treated sides. Adverse event duration was similar for both groups and generally resolved within 14 to 21 days. CONCLUSION This CaHA-based product gives significantly longer-lasting correction of nasolabial folds compared to human collagen. Less total material and fewer injections are required. The adverse event profile of the product is similar to the collagen-based product.