Purnima Amin

Development of hot melt co-formulated antimalarial solid dispersion system in fixed dose form (ARLUMELT): Evaluating amorphous state and in vivo performance.

The aim of this study was to investigate the industrial feasibility of developing a co-formulated solid dispersion (SD) containing two antimalarial drugs artemether (ARTM) and lumefantrine (LUMF). Soluplus(®) (polyethyleneglycol-polyvinyl caprolactam-polyvinyl acetate grafted copolymer) was used as primary carrier matrices via hot-melt extrusion processing to improve solubility profile and the oral bioavailability of the combination. Based on the preliminary screening, the optimized quantities of PEG 400, Lutrol F127 and Lutrol F68 were incorporated as surfactant with soluplus in different ratios to improve extrudability, increase wettability and the melt viscosity of the HME process. Soluplus(®) was proved to successfully stabilize both the drugs inside its polymeric network during extrusion via forming a stable solid dispersion. Physicochemical properties of the APIs and the SDs characterized by thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), MDSC, FTIR spectroscopy and X-ray diffractometry (XRD) revealed the amorphous existence of the drug in all SDs developed. Molecular level morphology of solid dispersion characterized by using advanced physicochemical characterization techniques such as Raman spectroscopy, atomic force microscopy (AFM) and 2D NMR showed the transformation of the crystalline drugs to its stable amorphous state. All manufactured SDs retained their amorphicity even after a stability study conducted in accelerated condition over 6 months. The solubility and in vitro dissolution performance of both drugs in SD formulations was improved significantly when compared with pure drugs and marketed product while the in vivo studies revealed the same.The pharmacokinetic studies in rats revealed that the SD (AL1) shows a 44.12-65.24 folds increase in the AUC(0-72) and 42.87-172.61 folds increase in Cmax compared to that of pure drugs and a better bioavailability than that of commercial product.

Liquid antisolvent precipitation process for solubility modulation of bicalutamide

Liquid antisolvent precipitation process for solubility modulation of bicalutamide Liquid antisolvent process was explored as a solubility modulating tool. Bicalutamide, a poorly water soluble drug, was used as a candidate. Low aqueous solubility and poor dissolution of bicalutamide results into poor and variable bioavailability. Therefore, the objective of the present work was to modify the solubility of bicalutamide using the liquid antisolvent precipitation process. HPMC E5 and Poloxamer 407 were shortlisted as a hydrophilic polymer and surfactant, respectively, for the process. Process optimization was done with respect to the hydrophilic polymer, surfactant and drug loading concentration. The resultant microcrystals were characterized with various instrumental techniques for material characterization such as IR, DSC, SEM, XRD, particle size, specific surface area and dissolution kinetics. Tekućinski antisolvent postupak taloženja za modifikaciju topljivosti bikalutamida Tekućinski antisolvent postupak upotrijebljen je za moduliranje topljivosti bikalutamida. Zbog vrlo slabe topljivosti u vodi i sporog oslobađanja, bioraspoloživost bikalutamida je mala i varijabilna. Cilj rada je poboljšati topljivost bikalutamida koristeći antisolvent precipitaciju. Kao hidrofilni polimer korišten je HPMC E5, a kao surfaktant Poloxamer 407. Variranjem količine polimera, surfaktanta i lijeka proces je optimiran. Nastali mikrokristali analizirani su uobičajenim instrumentalnim tehnikama za karakterizaciju materijala kao što su IR, DSC, SEM, XRD, veličina čestica, specifična površina i brzina oslobađanja.

Solubility and dissolution enhancement of efavirenz hot melt extruded amorphous solid dispersions using combination of polymeric blends: A QbD approach

Efavirenz is a non-nucleoside reverse transcriptase inhibitor and categorized in to BCS class II drug. The aim of the present investigation was to apply quality by design approach to enhance the solubility, dissolution and stability of amorphous solid dispersions (ASDs) of efavirenz using a combination of Soluplus® and HPMCAS-HF polymers. In design of experiments, the user defined quadratic model was used to study the effect of variable concentrations of Soluplus® and HPMCAS-HF for the formation of ASDs of efavirenz. Similarly, a prototype ASD was made using Soluplus® as a carrier with efavirenz loading of 30%. The efavirenz ASDs granular extrudates were evaluated for saturation solubility as well as dissolution rate studies. X-ray powder diffraction, Differential scanning calorimetry, Fourier transform infrared, Atomic force microscopy and FTIR imaging to determine the solid state of efavirenz in the ASDs. DSC and XRD data confirmed that bulk crystalline efavirenz transformed to the amorphous form during the hot melt extrusion processing. Prototype ASD batch showed instability upon storage as per ICH guidelines over a period of 6months, observations inferred from DSC, XRD and in vitro dissolution studies. The maximum dissolution rate was observed when Soluplus® and HPMCAS-HF was in ratio of (60:20) as optimized by design of experiments study. Moreover, the optimized ASDs batch were stable at 40°C, 75% RH for a period of 6months without any dissolution rate changes, and remained into amorphous state.

Porous Starch: a Novel Carrier for Solubility Enhancement of Carbamazepine

To circumvent the solubility-related issues associated with Biopharmaceutics Classification System class II drugs, a novel porous carrier has been developed. In the present study, a process for preparation of porous starch (PS) is demonstrated. The process briefly comprises of translucent gel preparation followed by solvent replacement, drying, and sizing. Carbamazepine (CBZ) was used as a drug candidate to exhibit solubility enhancement potential of PS. PS and CBZ-loaded PS (CBZ-PS) systems were characterized with respect to IR, DSC, XRD, SEM, and dissolution kinetic studies. PS-CBZ was found to follow a Fickian behavior during dissolution. In vivo studies conducted in mice displayed a superior performance of CBZ-PS as compared to neat CBZ.

Investigational Studies on Highly Purified Fenugreek Gum as Emulsifying Agent

In this study, highly purified galactomannan containing fenugreek gum was isolated by newly reported method and investigated for its surface and emulsification property. Comparative studies were carried out with other galactomannan containing natural emulsifiers like locust bean gum, guar gum, and non-galactomannan anionic xanthan gum. The results revealed that highly purified fenugreek gum has better surface and interfacial tension reducing property among all gums used in this study. Emulsion prepared with 0.6% highly purified fenugreek gum showed greater reduction in droplets size with greater surface area compared to guar gum, locust bean gum, and xanthan gum emulsion. Zeta potential values indicated that highly purified fenugreek gum emulsion showed greater repulsive forces and was able to form more stable emulsion compared to other gums. No coalescence or phase separation was observed during storage.

Solid crystal suspension of Efavirenz using hot melt extrusion: Exploring the role of crystalline polyols in improving solubility and dissolution rate

Poor aqueous solubility of drugs has emerged as a major issue for pharmaceutical scientists from many decades. The current study explores the manufacture and development of a thermodynamically stabilized solid crystal suspension (SCS) of poorly water soluble drug efavirenz via hot melt extrusion. Efavirenz is a non-nucleoside reverse transcriptase inhibitor and belongs to BCS class II. The SCS was prepared using pearlitol and xylitol as a crystalline carrier. The drug-excipient blend was processed by hot melt extrusion with up to 50% (w/w) drug loading. Physico-chemical characterization of the SCS conducted via a scanning electron microscopy, differential scanning calorimetry and hot stage microscopy confirmed that SCS are in crystalline state. Similarly, X-ray powder diffraction analysis revealed highly crystalline existence of pure drug, crystalline carriers and developed SCS. The FTIR chemical imaging analysis of SCS formulations showed a homogeneous drug distribution within respective crystalline carriers while an advanced chemical analysis via atomic force microscopy and Raman analysis complemented the foregoing findings. The developed SCS1 formulation showed up to 81 fold increase in the solubility and 4.1 fold increase in the dissolution rate of the drug compared to that of the bulk substance. Surprisingly, the developed SCS formulation remained stable for a period of more than one year at accelerated conditions inferred from dissolution studies. It can be concluded that the SCS approach can be used as an alternative contemporary technique to enhance the dissolution rates of many other poorly water-soluble drugs by means of thermal HME processing.

SOLUBILITY ENHANCEMENT OF CARVEDILOL USING LIQUISOLID COMPACT TECHNIQUE

A novel liquisolid compact technique was used for soulbility enahncement of poorly water soluble drug carvedilol (CAR). CAR was dissolved in water miscible non volatile solvent and then adsorbed on a solid carrier which was later compacted with other excipient into a tablet. The tablets were characterized with respect to hardness, friability, disintegration and in-vitro dissolution profile. Effect of storage conditions on dissolution profile was also studied. DSC and XRD studies were done to confirm the physical state of CAR in the formulation.

Extended release delivery system of metoprolol succinate using hot-melt extrusion: effect of release modifier on methacrylic acid copolymer

The current study reports on the manufacturing of extended release dosage forms of metoprolol succinate via hot-melt extrusion (HME) technology. Either Eudragit®S100 and Eudragit®L100 alone or in combination with release modifying agent Polyox™ WSR 303 and Eudragit®L100-55 were processed to obtain complete and faster release. Metoprolol succinate with similar solubility parameters to polymer was dispersed in polymer matrix and was characterized by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Stability of drug after extrusion was confirmed by thermogravimetric analysis and high-performance liquid chromatography. Physical characterization method exhibited that the drug was homogeneously dispersed in non-crystalline state in Eudragit®L100-55-based formulations whereas in semi-crystalline state in Polyox™ WSR 303. The drug release percentage was below 3 and 40% in 0.1xa0N HCL with Eudragit®L100-55- and Polyox™ WSR 303-containing formulations, respectively, and exhibited pH-dependent dissolution properties. The drug-release mechanism was anomalous with Polyox™ WSR 303 formulations whereas diffusion through pore formation was obtained with Eudragit®L100-55. Both Eudragit®L100-55 and Polyox™ WSR 303 changed the release mechanism and kinetics of drug release from thermally processed dosage forms. The optimized stable formulation is similar to the marketed formulation with F2 value of 72.36. Thus, it can be concluded that HME was exploited as an effective process for the preparation of controlled release matrix system based on pH-dependent polymer matrices Eudragit®S100 and Eudragit®L100.

Study the influence of formulation process parameters on solubility and dissolution enhancement of efavirenz solid solutions prepared by hot-melt extrusion: a QbD methodology

The current study investigates the dissolution rate performance of amorphous solid solutions of a poorly water-soluble drug, efavirenz (EFV), in amorphous Soluplus® (SOL) and Kollidon® VA 64 (KVA64) polymeric systems. For the purpose of the study, various formulations with varying drug loadings of 30, 50, and 70% w/w were developed via hot-melt extrusion processing and adopting a Box–Behnken design of experiment (DoE) approach. The polymers were selected based on the Hansen solubility parameter calculation and the prediction of the possible drug-polymer miscibility. In DoE experiments, a Box–Behnken factorial design was conducted to evaluate the effect of independent variables such as Soluplus® ratio (A1), HME screw speed (A2), and processing temperature (A3), and Kollidon®VA64 ratio (B1), screw speed (B2), and processing temperature (B3) on responses such as solubility (X1 and Y1) and dissolution rate (X2 and Y2) for both ASS [EFV:SOL] and BSS [EFV:KVA64] systems. DSC and XRD data confirmed that bulk crystalline EFV transformed to amorphous form during the HME processing. Advanced chemical analyses conducted via 2D COSY NMR, FTIR chemical imaging, AFM analysis, and FTIR showed that EFV was homogenously dispersed in the respective polymer matrices. The maximum solubility and dissolution rate was observed in formulations containing 30% EFV with both SOL and KVA64 alone. This could be attributed to the maximum drug-polymer miscibility in the optimized formulations. The actual and predicted values of both responses were found precise and close to each other.

Modified extrusion-spheronization as a technique of microencapsulation for stabilization of choline bitartrate using hydrogenated soya bean oil

Introduction: Choline bitartrate (CBT) is a vital nutrient for fetal brain development and memory function. It is hygroscopic in nature which is associated with stability related problem during storage such as development of fishy odor and discoloration. Aim: Microencapsulation method was adopted to resolve the stability problem and for this hydrogenated soya bean oil (HSO) was used as encapsulating agent. Materials and Methods: Industrially feasible modified extrusion-spheronization technique was selected for microencapsulation. HSO was used as encapsulating agent, hydroxypropyl methyl cellulose E5/E15 as binder and microcrystalline cellulose as spheronization aid. Formulated pellets were evaluated for parameters such as flow property, morphological characteristics, hardness-friability index (HFI), drug content, encapsulation efficiency, and in vitro drug release. The optimized formulations were also characterized for particle size (by laser diffractometry), differential scanning calorimetry, powder X-ray diffractometry (PXRD), Fourier transform infrared spectroscopy, and scanning electron microscopy. Results and Discussions: The results from the study showed that coating of 90% and 60% CBT was successful with respect to all desired evaluation parameters. Optimized formulation was kept for 6 months stability study as per ICH guidelines, and there was no change in color, moisture content, drug content, and no fishy odor was observed. Conclusion: Microencapsulated pellets of CBT using HSO as encapsulating agent were developed using modified extrusion spheronization technique. Optimized formulations, CBT 90% (F5), and CBT 60% (F10), were found to be stable for 4M and 6M, respectively, at accelerated conditions.