FORMULATION, IN VITRO, AND IN VIVO EVALUATION OF TASTE-MASKED ORAL DISINTEGRATING TABLETS OF FEXOFENADINE HYDROCHLORIDE USING SEMISYNTHETIC AND NATURAL SUPERDISINTEGRANTS

Objective: The aim of the present research work was to prepare and evaluate taste-masked oral disintegrating tablets (ODT) of Fexofenadine hydrochloride. Methods: In the present work, Eudragit EPO, a taste masking agent and Karaya gum (GK) (natural), Sodium starch glycolate, and Croscarmellose sodium (CCS) (semi-synthetic) super disintegrants in three ratios (3, 6,9%) were used. Taste masked granules were prepared by different ratios of the drug: Eudragit EPO (1:1, 1:1.5, 1:2) by wet granulation method. The optimized taste-masked granules (1:2) were selected by sensory evaluation test to prepare 9 Fexofenadine ODT (FH1-FH9) formulations. These were evaluated for different parameters. Then desirability function (DF) was calculated for all formulations using disintegration time (DT), time taken for the tablet to release 90% of the drug (t 90%), and % drug dissolved in 10 min (Q10) as significant parameters. Results: The best formulation (FH6) showed the highest DF value due to less DT and 100% in vitro drug release within 15 min. Thus, FH6 formulation containing 9% CCS was selected as the best among the prepared formulations to which in vivo studies were performed on rabbits to find maximum plasma concentration (Cmax), time taken to reach maximum concentration (tmax), area under the curve (AUC), rate of elimination (Kel), absorption rate (Ka) and half-life(t1/2) and compared with Fexofenadine (Allegra) marketed tablets. Total bioavailability was increased for the test formulation compared to the reference formulation. Conclusion: Fexofenadine was successfully prepared as ODT with increased AUC and decreased tmax to which stability studies were conducted which were found to be stable.

Formulation and evaluation of orally disintegrating tablet containing taste masked mirtazapine

Objective: This study aims to prepare the taste-masked granules of Mirtazapine by mass extrusion technique and formulate it into an oral dispersible tablet using different super disintegrates. Methods: Taste masked granules of mirtazapine were prepared by mass extrusion technique using Eudragit EPO in different ratios. The drug-polymer ratio was optimized based on the percent drug release in SSF and SGF. Taste masking efficacy of drug-polymer complex was determined by developing the bitterness threshold value of Mirtazapine. The selected drug-polymer complex was formulated into an oro-dispersible tablet by direct compression method. A randomized design was used to investigate individual effect of three different super disintegrates each in different concentrations. Ten formulations were developed including a controlled formulation without the addition of superdisintegrants. A comparative study was done based on various pre-compression and post-compression parameters. Results: Eudragit EPO was able to mask the bitter taste of Mirtazapine effectively in 1:2 ratio by mass extrusion method. The minimum disintegration time and wetting time was found to be 13.6±2.7 and 18.13±0.24 seconds with the formulation containing crospovidone 5% (F9). It was found that the wetting time and disintegration time followed the order SSG>CCS>CPV. The selected best formulation was subjected to an incompatibility study design. The IR spectrum showed that all the excipients were chemically compatible. Conclusion: Thus, in this study unpalatable taste of Mirtazapine was masked using Eudragit EPO polymer by mass extrusion technique, and superdisintegrants were added to prepare orally disintegrating tablets of Mirtazapine. This research work suggests a rapid, simple and cost effective method for formulating Mirtazapine ODT.

RP-HPLC method development and validation for the quantification of Efonidipine hydrochloride in HME processed solid dispersions

Background Efonidipine hydrochloride (EFO) is a poorly water-soluble drug and, hence, has poor bioavailability. Solid dispersions (SDs) of EFO using Eudragit EPO were prepared using hot-melt extrusion (HME) for the first time. The current study aims at developing a simple RP-HPLC method to quantify EFO in the developed SDs. Results The chromatographic separation was carried out on an Agilent Eclipsed XDB-C18 column (4.6 × 250 mm), packed with 5 μm particles. The optimized mobile phase consisted of HPLC grade acetonitrile and 0.020 mol/L KH2PO4 (pH 2.5) buffer in the ratio of 85:15 v/v with a flow rate optimized at 1.2 ml/min. The developed method was validated for system suitability, linearity, accuracy, precision, and robustness. The linearity results showed an excellent linear relationship between the drug concentration and peak area, indicating the peak area is directly proportional to the analyte concentration within a specific range and an excellent correlation coefficient of 0.9998. Intermediate precision and repeatability confirmed that the method provides precise results with %RSD value less than 2% for EFO. The assay results of the developed formulations were in the acceptable range with RSD less than 2%. The enhanced drug dissolution from the Eudragit EPO carrier with 10% Citric Acid (CA) is attributed to the conversion of the drug from crystalline to amorphous form, and microenvironmental acidic pH provided by CA. Conclusion In a nutshell, the developed RP-HPLC method showed excellent ability to differentiate the formulations and highlights the role of the polymer and the plasticizer. Graphical abstract

Taste Masking of Enalapril Maleate by the Precipitation Method

Background: Taste masking of bitter or unpleasant drugs is an important prerequisite to improve patient compliance, especially for children and elderly patients. We aimed at obtaining taste-masked microparticles intended for incorporation into orodispersible tablets (ODTs). We selected the precipitation method using enalapril maleate (ENA) as a model bitter-tasting drug and Eudragit EPO® as a pH sensitive polymer. Aim: The aim of this study was to obtain microparticles with enalapril maleate by the precipitation method in order to mask the bitter taste of the drug. Materials and methods: Nine models of enalapril maleate – Eudragit EPO® microparticles were prepared by the precipitation method at varied drug-polymer ratios. The models were characterized in terms of size, shape, production yield, drug content, encapsulation efficiency and moisture content. Fourier-transformed infrared spectroscopy, powder X-ray diffraction and differential scanning calorimetry were used to analyze possible interactions in the complex. In vitro drug release in simulated salivary fluid and in vivo taste evaluation in rats were realized to prove taste masking. Results: The particle size distribution varied from 266.9 µm to 410.9 µm. The shape of the resulting particles was irregular. The production yield varied from 23.6% to 78.2%. The drug content ranged between 2.3% to 4.8%, encapsulation efficiency increased from 1.6% to 9.0%. In vitro drug release data indicated significant taste masking. Conclusion: Some of the obtained microparticles by the precipitation method showed satisfactory taste masking efficiency, which proved the taste masking feasibility of this method.

DESIGNING A PLATFORM TECHNOLOGY FOR AGE APPROPRIATE PEDIATRIC DOSAGE FORM

Present work was aimed to develop a platform technology for pediatric dosage form which masks the bitter taste of a drug and to prepare flexible solid oral dosage form using hot melt extrusion (HME). Eudragit EPO, a cationic co-polymer insoluble in pH above 5, was used as a taste masking polymer to restrict the drug release in saliva. Soluplus, a graft co-polymer freely soluble in water was used as solubility enhancer. Test formulation released less than 10 % drug Tenofovir Disoproxil Fumarate (TDF) in pH 6.8 compared to 89% of marketed formulation simulated to limited release of drug in the saliva and thus avoiding the bitterness. DSC and XRD tests confirmed the existence of molecularly dispersed drug. FTIR confirmed the presence of unchanged functional groups of drug in its tablet form after HME processing. Proposed platform technology successfully masked the bitter taste in the ratio of D:P 1:2 and overcame this challenge of oral dosage form.

TASTE MASKING BY HOT MELT EXTRUSION WITHOUT LOSS OF BIOAVAILABILITY FOR PEDIATRICS

Objective: The aim of present work was to develop a platform technology for the pediatric dosage form to mask the bitter taste of Furosemide (FUR) and prepare a flexible solid oral dosage form. Methods: Excipient compatibility study was carried out by using Fourier-transform infrared spectroscopy (FTIR). Taste masking was done by hot melt extrusion (HME) technology. Eudragit EPO and Soluplus were used as a taste masking and solubilizing polymers respectively. The prepared solid dispersion and tablets were evaluated for their physicochemical parameters such as hardness, friability, disintegration, in vitro drug release. Results: Experimental data revealed that physical integrity, brittleness of granules, conversion of a drug in amorphous form was improved by combining Eudragit EPO with Soluplus. Plasticizer helped to complete HME at 80 °C. Less than 10% drug release in pH 6.8 medium revealed that release would be extremely limited in the saliva and thus avoiding bitterness. Animal study data revealed that bioavailability has been increased by 30%. Differential scanning calorimetry (DSC) and x-ray diffraction (XRD) tests confirmed the existence of molecularly dispersed drug. Fourier-transform infrared spectroscopy (FTIR) confirmed the unchanged functional groups of FUR after HME processing. Conclusion: Proposed platform technology masked the bitter taste and enhanced the bioavailability of FUR in D: P ratio of 1:2.