Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a decade of success in pharmaceutical and biomedical fields. Highly innovative personalized therapeutical solutions may be designed and manufactured through a layer-by-layer approach starting from a digital model realized according to the needs of a specific patient or a patient group. The combination of patient-tailored drug dose, dosage, or diagnostic form (shape and size) and drug release adjustment has the potential to ensure the optimal patient therapy. Among the different 3D printing techniques, extrusion-based technologies, such as fused filament fabrication (FFF) and semi solid extrusion (SSE), are the most investigated for their high versatility, precision, feasibility, and cheapness. This review provides an overview on different 3DP techniques to produce personalized drug delivery systems and medical devices, highlighting, for each method, the critical printing process parameters, the main starting materials, as well as advantages and limitations. Furthermore, the recent developments of fused filament fabrication and semi solid extrusion 3DP are discussed. In this regard, the current state of the art, based on a detailed literature survey of the different 3D products printed via extrusion-based techniques, envisioning future directions in the clinical applications and diffusion of such systems, is summarized.

A new polymeric construct is proposed as a starting material for a liver-targeted delivery system in the present communication. The polymeric material has been designed to be sensitive to pH variations and potentially loaded with hydrophobic antitumoral agents. It is based on one of the most used copolymers in the field of nanomedicine: PEG-PLA. The latter, usually obtained by polymerization of lactic acid on the hydroxyl-terminated polyether, is assembled by the pH-reversible condensation between a phenylboronic acid-ended methoxy PEG 2000 (MeO-PEG2000-PBA) and a galactose-capped PLA of 1–10 kDa (PLA-Gal). Our approach is based on the strategic assumption that would allow a new ligand presentation strategy in which Gal is both a structural element for the stimulus-responsive PEG de-shielding and the targeting moiety. Indeed, Gal has a vicinal diol able to form a reversible boronate ester with a B(OH) 2 residue, which is cleavable at the acidic pH of the tumor microenvironment, and it is also recognized by the asialoglycoprotein receptor, which is hyper-expressed on the membrane of hepatocytes. The functionalization of the two blocks is presented here, and they are characterized using NMR, FTIR, and GPC. The analytical evaluation of the ability of the boronated PEG and Gal to condense in a pH sensible way completes the study.