In this work, didofenac sodium pellets were produced through an extrusion/spheronization process and subsequently coated in a fluidized bed coater column with a Wurster insert. The aim of this work was to study the coating of pellets with two commercial aqueous enteric polymer suspensions, Advantia (R) Performance and Acryl-Eze (R) MP. The coating process was studied with a 2(3) experimental design. The variables were as follows: inlet air temperature, suspension flow rate and coating polymer. The response variables were as follows: the process efficiency, which generated results above 782%, and the agglomeration fraction, which generated results below 8%. The polymer coating type was the variable that influenced the response variables the most. The minimum masses gain needed to achieve enteric release were also determined: Actyl-Eze (R) MP: 9.7% and Advantia (R) Performance: 8.6%. The coated pellets were tested for drug content, dissolution and stability. Neither the drug content nor the release profiles were significantly affected by storage at 40 degrees C and 75%. The suspensions were tested for rheology, contact angle and static wettability to investigate the characteristics of the polymer. (C) 2014 Elsevier B.V. All rights reserved.