In this study, microscopic, histochemical and ultrastructural observations in human skin are presented, 8 months after an injection of a novel PEGylated filler. Morphological features demonstrated an excellent integration of the filler with the connective tissue components and an effective interpenetration with the ground substance. The filler appears uniformly distributed inside the hypodermis. No segregation or encapsulation of cells and other structures was observed nor evidence of immunological adverse reaction. Furthermore, observed ultrastructural modifications of fibroblasts supports a stimulatory effect of molecular components production of the extracellular matrix, contributing to the cutaneous connective tissue renewal.