From prototype to veterinary patient: a pharmacokinetic clinical trial of 3D-printed pimobendan tablets in beagle dogs

Pimobendan (PBD) is widely used to manage canine heart failure; however, commercially available formulations present limitations such as restricted dose flexibility and large tablet sizes, which may compromise long-term treatment individualisation. Three-dimensional (3D) printing offers a promising alternative by enabling customisable veterinary formulations. This study presents the first in vivo pharmacokinetic and clinical evaluation of 3D-printed PBD tablets (printlets) specifically designed for and administered to dogs. Printlets containing 2.5 mg of PBD were produced by semisolid extrusion 3D printing and compared with the commercial formulation Vetmedin®. Both formulations were characterised for weight, dimensions, drug content, and in vitro dissolution. They were orally administered to healthy Beagle dogs at a single dose of 0.2 mg/kg. Plasma PBD concentrations were quantified by LC–MS/MS, and pharmacokinetic parameters were determined by non-compartmental analysis. The 3D-printed printlets were safely administered, and no adverse effects were observed during the study. The pharmacokinetic evaluation demonstrated systemic exposure following oral administration of the 3D-printed formulation according to their sustained release profile, showing differences in absorption profiles compared with the commercial formulation. Overall, this study provides in vivo evidence supporting the feasibility of semisolid extrusion 3D printing for the preparation of veterinary PBD dosage forms and highlights the potential of digital manufacturing technologies for individualized veterinary therapy.