Prime objective of this research work was to the improve efficacy of a BCS class II drug, nabumetone (NBM). Nanostructured lipid carrier (NLC) of NBM was developed using melt-emulsification and ultrasonication technique. Prior to the formulation development, screening of various solid lipids, liquid lipids and surfactants were done and the most suitable excipients were selected. The NLC formulation was optimized using Box-Behnken Design Expert software. For optimization purpose, independent variables were taken as % lipid mix, % surfactant and sonication time ( minute). Particle size, PDI and entrapment efficiency were selected as dependent variables. The optimized formulation was characterized using photon correlation spectroscopy and was found with 127 +/- 1.75 nm average particle size and 0.279 +/- 0.016 polydispersity index (PDI). When observed under TEM and SEM, NLC particles were found with nearly spherical shape and particle size of NLC in this study almost matched with the average particle size determined by photon correlation spectroscopy. In DSC thermogram of NBM-NLC, the endothermic peak of the drug at 84.04 degrees C was disappeared that means drug was fully dissolved in lipid. In vitro release study of developed formulation showed burst release followed by slow diffusion based sustained release. The pharmacodynamic study shows better anti-inflammatory effect (almost 2 times) when compared with NBM suspension. Based on the data obtained from the in vitro and in vivo studies it was concluded that NLC can be a promising carrier and helps in improving intestinal absorption of orally administered NBM. (C) 2017 Elsevier B.V. All rights reserved.