ABSTRACT
OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: Meloxicam in situ implant may provide long-term management of inflammatory conditions with improved patient compliance and better therapeutic index.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Drug Carriers/chemistry , Lactic Acid/chemistry , Polyglycolic Acid/chemistry , Thiazines/administration & dosage , Thiazoles/administration & dosage , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacokinetics , Area Under Curve , Chemistry, Pharmaceutical/methods , Drug Compounding/methods , Drug Implants , Gels , Inhibitory Concentration 50 , Male , Meloxicam , Microscopy, Electron, Scanning , Polylactic Acid-Polyglycolic Acid Copolymer , Pyrrolidinones/chemistry , Rats , Rats, Sprague-Dawley , Spectroscopy, Fourier Transform Infrared , Thiazines/chemistry , Thiazines/pharmacokinetics , Thiazoles/chemistry , Thiazoles/pharmacokinetics , Viscosity , X-Ray DiffractionABSTRACT
The aim of this project was to develop and optimize indomethacin microcapsules composed of multiple mucoadhesive polymers for high drug entrapment, good mucoadhesiveness and drug release in a controlled fashion over a longer period of time. Microcapsules containing sodium alginate, sodium carboxymethylcellulose, methylcellulose, Carbopol 934 and hydroxypropyl methylcellulose were prepared by orifice-ionic gelation method. The effects of composition of microcapsules on drug entrapment efficacy, drug release and mucoadhesive character were determined by mixture statistical design. Most formulations exhibited good mucoadhesive property in everted intestinal sac test. Drug entrapment efficiency (68-94%) was dependent on the type of polymers. Drug release (92-100%) extended over 12 h. The optimized formulation resulted in drug entrapment efficiency of 89.3%, drug release of 94.8% and mucoadhesiveness of 30.4%. All formulations were stable for more than 1.5 years. The optimized mucoadhesive microcapsules are promising for controlled delivery of indomethacin with twice a day oral administration.
