BackgroundInjectable fillers for soft tissue augmentation stand out as one of the most favored procedures in the field of aesthetic medicine, especially in addressing the clinical signs of skin aging. Among soft tissue fillers, non‐permanent fillers have been safely used in numerous medical applications for several decades.AimsThe aim of this post‐market observational, open‐label, uncontrolled, multicentered, prospective study (PMS) was to evaluate the effects of an injectable poly‐L‐lactic acid‐based collagen stimulator (Lanluma®, the study product).Participants/MethodsThis analysis is based on the clinical outcomes data (safety and effectiveness) collected from investigators and participants between the first injection (T0, September 2022) and 9 months thereafter (T3, June 2023) in the treatment of five body‐contouring areas.ResultsOverall, 70 participants had 99 treatment sessions of the neck (31%), upper arm (20%), hand (17%), thigh (16%) and décolleté (15%). Lumps (neck, upper arm, hand) and nodules (neck, hand, thigh) were the most frequent adverse events (AEs) reported by investigators. All were treatment related. None were serious, severe or fatal. No AEs were reported following treatment of the décolleté. Both investigators and participants reported high levels of satisfaction during the nine‐month follow‐up period with the treatments in five body areas.ConclusionsThese positive clinical outcomes can be attributed to a proper implementation of best practices and recommendations, and the rheological properties of the study product. This 9‐month follow‐up analysis should be reconsidered in light of the study's objectives for the final analysis at the 25‐month follow‐up.