Semi solid matrix formulations of meloxicam and tenoxicam: an in vitro and in vivo evaluation

Formulation and Evaluation of Meloxicam Hybrid nano Particles

The goal of the present study was to prepare meloxicam (MX) entrapped hybrid particles (HPs) to enhance intestinal permeation and anti-inflammatory activity. MX-HPs were prepared by nanoprecipitation method using lipid, chitosan, poloxamer, and TPGS. The formulations (MX-HPs1, MX-HPs2, MX-HPs3) were evaluated for particle size, entrapment efficiency, and drug release to select the optimized composition and further evaluated for permeation study, stability study, morphology, interaction study, and anti-inflammatory activity by carrageenan-induced rat paw edema test. The prepared MX-HPs showed nano sized particles (198.5 ± 3.7 to 223.8 ± 2.1 nm) and PDI (<0.3), zeta potential (16.5 ± 2.7 to 29.1 ± 3.6 mV), and high entrapment efficiency (75.1 ± 4.7 to 88.5 ± 3.9%). The surface morphology was assessed by transmission electron microscopy and showed non-aggregated particles. Infra-red (IR) spectroscopy of pure MX as well as formulation revealed no drug-polymer interaction and X-ray diffraction confirmed the conversion of crystalline MX into amorphous form. The release study data revealed prolonged MX release for 24 h. The selected optimized hybrid particles (MX-HPs2) revealed a 2.3-fold improved enhancement ratio than free MX. The storage stability and gastrointestinal stability data demonstrated a stable formulation in SIF as well as SGF. The anti-inflammatory activity showed better therapeutic action than pure MX dispersion. From the study, it can be concluded that the prepared MX-HPs may be a promising delivery system for MX in treating inflammatory disorders.

Preparation of Piroxicam nanosuspensions by high pressure homogenization and evaluation of improved bioavailability

OBJECTIVE

Inflammation is a natural response of the organism, involving events responsible for releasing chemical mediators and requiring treatments of symptoms such as pain, redness, heat, swelling, and loss of tissue function. Piroxicam (PRX) is a non-steroidal anti-inflammatory drug with the effect of nonselective COX inhibitor activity; however, it shows poor bioavailability caused by the poor and slow water solubility. In this study, we developed PRX nanosuspensions with 200-500 nm in diameter to increase the bioavailability of PRX by improving its solubility.

METHODS

PRX nanosuspensions were fabricated by High pressure homogenization method with PVA, SDS and Tween 80. The nanosuspensions were characterized by XRD, FTIR, DSC, and in vitro release. In vivo pharmacokinetic properties and anti-inflammatory effects were also investigated in rabbits.

RESULTS

PRX nanosuspensions significantly increased the solubility (14.89 ± 0.03 mg/L for pure PRX and 16.75 ± 0.05 mg/L for PRX nanosuspensions) and dissolution rate as compared to the pure PRX (p < 0.05). Orally administered PRX nanosuspension (AUC 0-t is 49.26 ± 4.29 μg/mL × h) significantly improved the bioavailability of PRX (AUC 0-t is 28.40 ± 12.11 μg/mL × h). The anti-inflammatory effect of PRX nanosuspension was also investigated in rabbits and it was observed that PRX nanosuspension treatment significantly improved the inhibition of COX-2 and NFκB expression as compared to the PRX treatment (p < 0.05).

CONCLUSIONS

The results in this study indicate that PRX nanosuspension is a promising nanomedicine for enhancing the anti-inflammatory activity of PRX and has a high potential for the treatment of inflammation.

Eutectic phase transition during tablet manufacture: effect of melting point of eutectic forming drug

The aim was to investigate eutectic transition during tableting and storage. Mixtures of lidocaine and series of NSAIDs with increasing melting point were used as model systems to guide formulators to scaleup eutectic forming materials gaining enhanced dissolution while avoiding deleterious physical changes. Physical mixtures of NSAIDs with lidocaine were prepared at eutectic forming ratio. These were directly compressed, dry co-ground before compression, or compressed after wet granulation. Dissolution of tablets was compared to corresponding dry co-ground mixture. Thermograms of direct compressed tablet were compared to co-ground mixture and pure compound. Stability of direct compressed tablets was assessed. Tableting initiated eutexia which enhanced dissolution of NSAIDs. Eutexia was associated with tablet softening in case of low melting point ketoprofen and aceclofenac. Wet granulation hastened eutexia developing unacceptable tablet in case ketoprofen and aceclofenac. Tablets prepared by direct compression of physical mixtures underwent gradual eutectic transition upon storage with the magnitude of eutectic transition reducing with increased melting point of NSAIDs. Ketoprofen was physically unstable but aceclofenac degraded chemically as well. Tenoxicam and meloxicam tablets were physically and chemically stable. Direct compression after physical mixing is the best tableting technique, but low melting point drugs should consider different strategy before compression.

Solid Dispersion of Tenoxicam – HPMC by Freeze-Drying: Solid State Properties, Dissolution Study, and Analgesic Activity in Mice

AIM: The aim of this study was to prepare solid dispersion of tenoxicam with hydroxypropyl methylcellulose (HPMC) to improve solubility, dissolution rate, and in vivo analgesic activity. METHODS: Solid dispersion of tenoxicam with HPMC was prepared using the freeze-drying technique in three ratios of drug to carrier (1:1, 1:2, and 2:1 w/w). The s olid-state properties of solid dispersion powders were characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, and scanning electron microscope (SEM). Solubility and dissolution rate studies were conducted in an aqueous medium. Analgesic activity was evaluated using the writhing method. RESULTS: Analysis of PXRD and DSC results indicated a decreased degree of crystallinity of tenoxicam in solid dispersion powders. Solid dispersion of tenoxicam exhibited a significant improvement in solubility and dissolution rate compared to intact tenoxicam, in line to the increment on the ratio of HPMC. Analgesic activity study revealed that solid dispersion 1:2 was more effective than intact tenoxicam. CONCLUSIONS: This study concludes that the solid dispersion technique is a promising strategy to improve the solubility and dissolution rate of tenoxicam.

Polymeric Films Containing Tenoxicam as Prospective Transdermal Drug Delivery Systems: Design and Characterization

The administration of drugs via transdermal therapeutic systems has become an attractive form of therapeutic approach, considering its advantages and the high patient compliance achieved, making them a viable alternative, especially in the treatment of chronic diseases. The purpose of our study was the development of polymer-based films containing tenoxicam (TX) and the analysis of dissolution kinetics. Auxiliary substances represent an important part of pharmaceutical forms, so during the first stage, TX and excipient compatibility were verified. Fourier Transform Infrared Spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC) analyses were performed on TX and on physical mixtures of TX-HPMCE5 and TX-HPMC15kcP. Three polymeric films of TX (TX1, TX2, and TX3) were prepared using a solvent evaporation technique. Release studies were done at 32 °C ± 1 °C with a Franz diffusion cell. The results of the DSC and FT-IR analyses demonstrated the compatibility of the active substance with the two matrix-forming polymers. The results obtained in the release studies of TX from the proposed polymeric films suggested a pH-dependent behavior in all three polymeric films. At pH 5.5, flux values were between 8.058 ± 0.125 μg·cm−2·h−1 and 10.850 ± 0.380 μg·cm−2·h−1; and at pH 7.4, between 10.990 ± 0.2.490 μg·cm−2·h−1 and 53.140 ± 0.196 μg·cm−2·h−1. The Korsmeyer–Peppas model described a non-Fickian transport mechanism. The n values varied between 0.63–0.7 at pH 5.5 and 0.73–0.86 at pH 7.4, which suggested a diffusion depending on the matrix hydration and polymer relaxation.

Evaluation of Mechanical Properties of Nonsteroidal Anti-Inflammatory Matrix Type Transdermal Therapeutic Systems

Objective: Transdermal therapeutic systems (TTSs) represent an intensely studied alternative to oral delivery of non-steroid anti-inflammatory drugs (NSAIDs) in the treatment of rheumatic diseases due to its ability of avoiding the side effects of the oral route. This study aims to present the evaluation of the mechanical properties of three NSAIDs (meloxicam, tenoxicam and indomethacin) individually included in four type of polymeric matrixes, as part of new formulations development process. Methods: 12 products in form of TTS matrixes were prepared by solvent casting evaporation technique, using hydroxypropyl methylcellulose (HPMC 15000, HPMC E5) and/or ethylcellulose as matrix-forming polymers. Each of the resulted products was evaluated by determining the water vapor absorption, desorption or transmission in controlled atmosphere humidity (evaluation of porosity); the elongation capacity, tensile strength and bioadhesiveness (evaluation of mechanical properties). Results: The analysis of three groups of the experimental data expressed as averages on each group was necessary, in order to identify the parameters which statistically are critically influenced by the ingredients associated in the TTSs matrix compositions. Analysis by normality tests, variance and correlation tests (Anova, Pearson) enabled evaluation of the effect of NSAID type vs. the effect of polymer matrix type on the parameters of the NSAID TTS matrix. Conclusions: Meloxicam incorporated in the structure of HPMC 15000 polymeric matrix favors its viscoelastic structure. Ethylcellulose functions as plasticizer and supports the matrix bioadhesiveness. HPMC E5 does not meet the requirements for TTS preparation in the used experimental conditions.