Development of meloxicam in situ implant formulation by quality by design principle

The focus of this study was to develop and optimize in situ implant formulation of meloxicam by quality by design (QbD) principle for long-term management of musculoskeletal inflammatory disorders.

The formulation was optimized by Box-Behnken design with polylactide-co-glycolide (PLGA) level (X1), N-methyl pyrrolidone level (X2) and PLGA intrinsic viscosity (X3) as the independent variables and initial burst release of drug (Y1), cumulative release (Y2), and dissolution efficiency (Y3) as the dependent variables. The formulation was physicochemically characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy and powder X-ray diffraction (PXRD). Pharmacokinetic studies of the optimized formulation were performed on Sprague-Dawley rats.

Y1 was significantly affected by X2 and X3. Y2 was affected by X1 and X3 while Y3 was affected by all three independent variables employed in the formulations. Responses for the optimized formulation were in close agreement with the values predicted by the model. SEM photomicrographs indicated uniform gel formulation. No chemical interaction between the components of formulation was observed by FT-IR and meloxicam was found to be present in the amorphous form in the gel matrix as revealed by PXRD. The maximum plasma concentration (Cmax), time to achieve Cmax and area under plasma concentration curve were significantly different from those of the solution formulation used as the control. Plasma concentration of meloxicam was maintained above its IC50 concentration required for COX-2 inhibition for 23 days.

Meloxicam in situ implant may provide long-term management of inflammatory conditions with improved patient compliance and better therapeutic index.