Abstract Injectable collagen stimulators have traditionally been linked to inflammatory foreign-body reactions (FBR) as a mechanism of action. However, the next-generation PLLA-LASYNPRO microspheres, contained in the CE-marked JULÄINE medical device, may represent a paradigm shift. Preclinical data suggest these microspheres can promote collagen and extracellular matrix (ECM) regeneration with minimal inflammatory response. This study aimed to evaluate the scientific soundness and clinical relevance of a non-inflammatory mechanism of action for PLLA-LASYNPRO. The central hypothesis was that design and manufacturing innovations could enable effective biostimulation while reducing inflammation and long-term tissue reactions. A structured expert board meeting was convened to assess the rationale and implications of this emerging mechanism. The process included a preliminary survey and an in-person consensus meeting involving multidisciplinary specialists in aesthetic and regenerative medicine. On January 24, 2025, 13 experts in aesthetic medicine, dermatology, and plastic surgery participated in a board meeting held in Milan, Italy. Scientific literature and preclinical data were reviewed in advance. Discussions were organized around biophysical characteristics, tissue integration, inflammatory profile, and safety considerations. The board considered the non-inflammatory mechanism of PLLA-LASYNPRO both biologically plausible and clinically promising. Key differentiating features included particle morphology, lack of excipients, and manufacturing purity. The panel highlighted the potential to reduce chronic inflammation, a known limitation of traditional collagen stimulators. Early clinical impressions supported this hypothesis, although prospective data are still forthcoming. This manuscript presents the consensus of a multidisciplinary board on the rationale for PLLA-LASYNPRO in aesthetic and regenerative medicine. It forms the first part of a two-paper series. The second manuscript will provide practical clinical guidance for the deep dermal administration of PLLA-LASYNPRO and real-world use of JULÄINE.
Bertossi et al. (Fri,) studied this question.