Solid dispersions: a strategy for poorly aqueous soluble drugs and technology updates

Self-micellizing solid dispersion of thymoquinone with enhanced biopharmaceutical and nephroprotective effects

The present study was designed to develop a self-micellizing solid dispersion (SMSD) containing Thymoquinone (TQM), a phytonutrient obtained from Nigella sativa seeds, aiming to improve its biopharmaceutical and nephroprotective functions. The apparent solubility of TQM in polymer solutions was used to choose an appropriate amphiphilic polymer that could be used to make an SMSD system. Based on the apparent solubility, Soluplus® was selected as an appropriate carrier, and mixing with TQM, SMSD-TQM with different loadings of TQM (5-15%) was made by solvent evaporation and freeze-drying techniques, respectively, and the formulations were optimized. The optimized SMSD-TQM was evaluated in terms of particle size distribution, morphology, release characteristics, pharmacokinetic behavior, and nephroprotective effects in a rat model of acute kidney injury. SMSD-TQM significantly improved the dissolution characteristics (97.8%) of TQM in water within 60 min. Oral administration of SMSD-TQM in rats exhibited a 4.9-fold higher systemic exposure than crystalline TQM. In a cisplatin-induced (6 mg/kg, i.p.) acute kidney-damaged rat model, oral SMSD-TQM (10 mg/kg) improved the nephroprotective effects of TQM based on the results of kidney biomarkers and histological abnormalities. These findings suggest that SMSD-TQM might be efficacious in enhancing the nephroprotective effect of TQM by overcoming biopharmaceutical limitations.

Enhanced Stability and Improved Oral Absorption of Enzalutamide with Self-Nanoemulsifying Drug Delivery System

The purpose of this study is to develop and evaluate a self-nanoemulsifying drug delivery system (SNEDDS) to improve the oral absorption of poorly water-soluble enzalutamide (ENZ). Considering the rapid recrystallization of the drug, based on solubility and crystallization tests in various oils, surfactants and co-surfactants, Labrafac PG 10%, Solutol HS15 80%, and Transcutol P 10%, which showed the most stable particle size and polydispersity index (PDI) without drug precipitation, were selected as the optimal SNEDDS formulation. The optimized SNEDDS formulation showed excellent dissolution profiles for all the drugs released at 10 min of dissolution due to the increased surface area with a small particle size of approximately 16 nm. Additionally, it was confirmed to be stable without significant differences in physical and chemical properties for 6 months under accelerated conditions (40 ± 2 °C, 75 ± 5% RH) and stressed conditions (60 ± 2 °C). Associated with the high dissolutions of ENZ, pharmacokinetic parameters were also greatly improved. Specifically, the AUC was 1.9 times higher and the Cmax was 1.8 times higher than those of commercial products (Xtandi® soft capsule), resulting in improved oral absorption. Taken together with the results mentioned above, the SNEDDS could be an effective tool as a formulation for ENZ and other similar drugs.

Improvement in Inhalation Properties of Theophylline and Levofloxacin by Co-Amorphization and Enhancement in Its Stability by Addition of Amino Acid as a Third Component

Co-amorphous systems are amorphous formulations stabilized by the miscible dispersion of small molecules. This study aimed to design a stable co-amorphous system for the co-delivery of two drugs to the lungs as an inhaled formulation. Theophylline (THE) and levofloxacin (LEV) were used as model drugs for treating lung infection with inflammation. Leucine (LEU) or tryptophan (TRP) was employed as the third component to improve the inhalation properties. The co-amorphous system containing THE and LEV in an equal molar ratio was successfully prepared via spray drying where reduction of the particle size and change to the spherical morphology were observed. The addition of LEU or TRP at a one-tenth molar ratio to THE-LEV did not affect the formation of the co-amorphous system, but only TRP acted as an antiplasticizer. The Fourier transform infrared spectroscopy spectra revealed intermolecular interactions between THE and LEV in the co-amorphous system that were retained after the addition of LEU or TRP. The co-amorphous THE-LEV system exhibited better in vitro aerodynamic performance than a physical mixture of these compounds and permitted the simultaneous delivery of both drugs in various stages. The co-amorphous THE-LEV system crystallized at 40 °C, and this crystallization was not prevented by LEU. However, THE-LEV-TRP maintained its amorphous state for 1 month. Thus, TRP can act as a third component to improve the physical stability of the co-amorphous THE-LEV system, while maintaining the enhanced aerodynamic properties.

A Comparative Study on Cyclodextrin Derivatives in Improving Oral Bioavailability of Etoricoxib as a Model Drug: Formulation and Evaluation of Solid Dispersion-Based Fast-Dissolving Tablets

Etoricoxib, as a model drug, has a poor solubility and dissolution rate. Cyclodextrin derivatives can be used to solve such a problem. A comparative study was run on three cyclodextrin derivatives, namely β-CD, HP β-CD, and SBE β-CD, to solve the drug problem through the formulation of solid dispersions and their preparation into fast-dissolving tablets. Preparations utilized different (1:1, 1:2, and 1:4) drug:carrier ratios. Nine fast-dissolving tablets (containing 1:4 drug: carrier) were formulated using Prosolv ODT® and/or F-melt® type C as super-disintegrants. Optimized formulation was chosen based on a 32 factorial design. The responses chosen were the outcomes of the in vitro evaluation tests. The optimized formulation that had the highest desirability (0.86) was found to be SD-HP3, which was prepared from etoricoxib: HP β-CD at a 1:4 ratio using equal amounts of Prosolv ODT® and F-melt® type C. An in vivo evaluation of SD-HP3 on a rabbit model revealed its superiority over the marketed product Arcoxia®. SD-HP3 showed a significantly lower Tmax (13.3 min) and a significantly higher Cmax (9122.156 μg/mL), as well as a significantly higher AUC, than Arcoxia®. Thus, the solubility, dissolution, and bioavailability of etoricoxib were significantly enhanced.

Enhanced Efficacy of Carvedilol by Utilization of Solid Dispersion and Other Novel Strategies: A Review

Carvedilol is classified as a second class drug of Biopharmaceutical classification system (BCS), and it is an excellent beta blocker and vasodilating agent. It is used in a diverse range of disease states. Despite having tremendous advantages, the drug cannot be used effectively and productively due to aquaphobicity and poor bioavailability. To overcome this limitation, numerous novel approaches and tactics have been introduced over the past few years, such as Selfmicro emulsifying drug delivery systems (SMEDDS), nanoparticles, solid dispersions and liposomal drug delivery. The present review aims to accentuate the role of solid dispersion in improving the dissolution profile and aqua solubility of carvedilol and also to emphasize other novel formulations of carvedilol proposed to prevail the limitations of carvedilol. Solid dispersion and other novel approaches were found to play a significant role in overcoming the drawbacks of carvedilol, among which solid dispersion is the most feasible and effective approach being used worldwide. Reduced particle size, more wettability, and large surface area are obtained by the implementation of solid dispersion technique, hence improving carvedilol solubility and bioavailability.

Pharmaceutical and Pharmacological Evaluation of Amoxicillin after Solubility Enhancement Using the Spray Drying Technique

The dose frequency of drugs belonging to class II is usually high and associated with harmful effects on the body. The study aimed to enhance the solubility of the poorly water-soluble drug amoxicillin (AM) by the solid dispersion (SD) technique. Six different SDs of AM, F1-F6, were prepared by the spray drying technique using two other carriers, HP-β-CD (F1-F3) and HPMC (F4-F6), in 1:1, 1:2, and 1:3 drug-to-polymer ratios. These SDs were analyzed to determine their practical yield, drug content, and aqueous solubility using analytical techniques such as Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and powder X-ray diffraction. The effect of polymer concentration on SDs was determined using aqueous solubility, in vitro dissolution, and in vivo studies. The results showed no drug-polymer interactions in SDs. Solubility studies showed that SDs based on the drug-to-polymer ratio of 1:2 (F2 and F5) were highly soluble in water compared to those with ratios of 1:1 and 1:3. In vitro dissolution studies also showed that SDs with a ratio of 1:2 released the highest drug concentration from both polymeric systems. The SDs based on HPMC confirmed the more sustained release of the drug as compared to that of HP-β-CD. All the SDs were observed as stable and amorphous, with a smooth spherical surface. In vivo studies reveal the enhancement of pharmacokinetics parameters as compared to standard AM. Hence, it is confirmed that spray drying is an excellent technique to enhance the solubility of AM in an aqueous medium. This may contribute to the enhancement of the pharmacokinetic behaviors of SDs.

Platensimycin-berberine chloride co-amorphous drug system: Sustained release and prolonged half-life

Co-amorphous technology is an emerging approach for pharmaceutical engineering of drugs and drug leads with improved physicochemical properties and bioavailability. Platensimycin (PTM) is a promising natural antibiotic lead that acts on bacterial fatty acid synthase and exhibits excellent antibacterial activity. Despite great strides to improve its poor pharmacokinetics by medicinal chemistry and nanotechnology, there are no convenient oral delivery systems developed. Here, a co-amorphous system of PTM and berberine chloride (BCL) was developed for oral delivery of PTM. Co-amorphous PTM-BCL was prepared by rotary vacuum evaporation method, and systematically characterized by powder X-ray diffraction, temperature modulated differential scanning calorimetry, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Compared with PTM or BCL alone, the equilibrium solubility and dissolution rate of both of them in the co-amorphous systems decreased significantly, showing the characteristics of sustained release. The molecular interactions between PTM and BCL were mediated by strong charged-mediated hydrogen bonds, based on FTIR, XPS, and NMR-based techniques. The co-amorphous PTM-BCL system showed excellent physiochemical stability at room and elevated (40 °C) temperature under dry conditions. The combination of PTM and BCL showed increased killing of a clinical isolated methicillin-resistant Staphylococcus aureus strain in killing checkerboard assays. Finally, co-amorphous PTM-BCL exhibited 2- or 3-fold longer half-life in rats than that of crystalline and amorphous PTM upon oral administration, respectively. Our study suggests a rational approach to realize the full potential of potent antibiotic PTM, which may be conveniently adapted for engineering of other important pharmaceutics.

Physical stability and dissolution behaviors of amorphous pharmaceutical solids: Role of surface and interface effects

Amorphous pharmaceutical solids (APS) are single- or multi-component systems in which drugs exist in high-energy states with long-range disordered molecular packing. APSs have become one of the most effective and widely used pharmaceutical delivery approaches for poorly water-soluble drugs in the last several decades. Considerable efforts have been made to investigate the physical stability and dissolution behaviors of APSs, however, the underlying mechanisms remain imperfectly understood. Recent studies reveal that surface and interface properties of APSs could strongly affect the physical stability and dissolution behaviors. This paper provides a comprehensive overview of recent studies focusing on the physical stability and dissolution behaviors of APSs from both surface and interface perspectives. We highlight the role of surface or interface properties in nucleation, crystal growth, phase separation, dissolution, and supersaturation. Meanwhile, the challenges and scope of research on surface and interface properties in the future are also briefly discussed. This review contributes to a better understanding of the surface- and interface-facilitated processes, which will provide more efficient and rational guidance for the design of APSs.

Solid dispersion technology as a formulation strategy for the fabrication of modified release dosage forms: A comprehensive review

Solubility limited bioavailability is one of the crucial parameters that affect the formulation development of the new chemical entities. Thus the major constraint in the pharmaceutical product development is the suitable solubility enhancement technique for Active Pharmaceutical Ingredient. Solid dispersion (SD) is an established and preferred method for improving the solubility which ultimately may be helpful to enhance bioavailability. For long period of time Amorphous solid dispersion (ASD) have been preferred for improving solubility, but since last two decades, ASD approach have been combined with different modified release approaches to improvise the stability and site specificity of SD to grasp a hold over the specific advantages associated with such dosage forms. It is an established fact now that the SD technique not only improves solubility limited bioavailability, but it may be combined with other approaches to modify the drug release profile from the formulation as per the requirement based on the apt selection of SD carriers and suitable technology. This review covers the comprehensive overview of all such formulations where SD technology is used to serve dual purpose rather than only the sole purpose of solubility enhancement. The SD approach has been successfully implemented for some of the poorly soluble herbal drugs and still there is a vast scope of advancement in that area. The current review will provide a broad outcome in the area of SD technology for modified release formulations along with the description of current status and future prospective of SD. The SD formed by dispersing drug within the conventional carrier to form ASD increases solubility, dissolution rate and bioavailability; whereas fourth generation hydrophobic carriers provide added advantage of controlled release (CR) or sustained release (SR) profile along with enhanced stability of SD. On the other frontier, pH dependant carriers enable the SD to achieve site specificity or delayed release (DR) profile.

A Hot-Melt Extrusion Risk Assessment Classification System for Amorphous Solid Dispersion Formulation Development

Several literature publications have described the potential application of active pharmaceutical ingredient (API)–polymer phase diagrams to identify appropriate temperature ranges for processing amorphous solid dispersion (ASD) formulations via the hot-melt extrusion (HME) technique. However, systematic investigations and reliable applications of the phase diagram as a risk assessment tool for HME are non-existent. Accordingly, within AbbVie, an HME risk classification system (HCS) based on API–polymer phase diagrams has been developed as a material-sparing tool for the early risk assessment of especially high melting temperature APIs, which are typically considered unsuitable for HME. The essence of the HCS is to provide an API risk categorization framework for the development of ASDs via the HME process. The proposed classification system is based on the recognition that the manufacture of crystal-free ASD using the HME process fundamentally depends on the ability of the melt temperature to reach the API’s thermodynamic solubility temperature or above. Furthermore, we explored the API–polymer phase diagram as a simple tool for process design space selection pertaining to API or polymer thermal degradation regions and glass transition temperature-related dissolution kinetics limitations. Application of the HCS was demonstrated via HME experiments with two high melting temperature APIs, sulfamerazine and telmisartan, with the polymers Copovidone and Soluplus. Analysis of the resulting ASDs in terms of the residual crystallinity and degradation showed excellent agreement with the preassigned HCS class. Within AbbVie, the HCS concept has been successfully applied to more than 60 different APIs over the last 8 years as a robust validated risk assessment and quality-by-design (QbD) tool for the development of HME ASDs.

Molecular-Level Examination of Amorphous Solid Dispersion Dissolution

Amorphous solid dispersions (ASDs) are commonly used to orally deliver small-molecule drugs that are poorly water-soluble. ASDs consist of drug molecules in the amorphous form which are dispersed in a hydrophilic polymer matrix. Producing a high-performance ASD is critical for effective drug delivery and depends on many factors such as solubility of the drug in the matrix and the rate of drug release in aqueous medium (dissolution), which is linked to bioperformance. Often, researchers perform a large number of design iterations to achieve this objective. A detailed molecular-level understanding of the mechanisms behind ASD dissolution behavior would aid in the screening, designing, and optimization of ASD formulations and would minimize the need for testing a wide variety of prototype formulations. Molecular dynamics and related types of simulations, which model the collective behavior of molecules in condensed phase systems, can provide unique insights into these mechanisms. To study the effectiveness of these simulation techniques in ASD formulation dissolution, we carried out dissipative particle dynamics simulations, which are particularly an efficient form of molecular dynamics calculations. We studied two stages of the dissolution process: the early-stage of the dissolution process, which focuses on the dissolution at the ASD/water interface, and the late-stage of the dissolution process, where significant drug release would have occurred and there would be a mixture of drug and polymer molecules in a predominantly aqueous environment. Experimentally, we used Fourier transform infrared spectroscopy to study the interactions between drugs, polymers, and water in the dry and wet states and the chromatographic technique to study the rate of drug and polymer release. Both experiments and simulations provided evidence of polymer microstructures and drug-polymer interactions as important factors for the dissolution behavior of the investigated ASDs, consistent with previous work by Pudlas et al. (Eur. J. Pharm. Sci. 2015, 67, 21-31). As experimental and simulation results are consistent and complementary, it is clear that there is significant potential for combined experimental and computational research for a detailed understanding of ASD formulations and, hence, formulation optimization.

Bubble-induced fast crystal growth of indomethacin polymorphs in a supercooled liquid

Physical stability is one of the main challenges when developing robust amorphous pharmaceutical formulations. This article reports fast crystal growth behaviors of the γ and α forms of indomethacin (IMC) initiated by bubbles in the interior of a supercooled liquid. Bubble-induced crystal growth of γ-IMC exhibits approximately the same kinetics as its surface crystal growth, supporting the view that bubble-induced crystal growth is a surface-facilitated process. In contrast, the rates of bubble-induced crystal growth of α-IMC are much faster than those of its surface crystal growth. These results indicate that the bubble-induced crystal growth not only depends on the interface created by the bubble but also strongly correlates with the true cavitation of the bubble. Moreover, bubble-induced fast crystal growth of γ- and α-IMC can be terminated at different temperatures by cooling. These outcomes are meaningful for the in-depth understanding of physical stability and pre-formulation study of amorphous pharmaceutical solids showing surface-facilitated crystal growth.

Preparation of Solid Dispersions of Simvastatin and Soluplus Using a Single-Step Organic Solvent-Free Supercritical Fluid Process for the Drug Solubility and Dissolution Rate Enhancement

The study was designed to investigate the feasibility of supercritical carbon dioxide (scCO₂) processing for the preparation of simvastatin (SIM) solid dispersions (SDs) in Soluplus^® (SOL) at temperatures below polymer’s glass transition. The SIM content in the SDs experimental design was kept at 10, 20 and 30% to study the effect of the drug–polymer ratio on the successful preparation of SDs. The SIM–SOL formulations, physical mixtures (PMs) and SDs were evaluated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and dissolution studies. The scCO₂ processing conditions and drug–polymer ratio were found to influence the physicochemical properties of the drug in formulated SDs. SIM is a highly crystalline drug; however, physicochemical characterisation carried out by SEM, DSC, and XRD demonstrated the presence of SIM in amorphous nature within the SDs. The SIM–SOL SDs showed enhanced drug dissolution rates, with 100% being released within 45 min. Moreover, the drug dissolution from SDs was faster and higher in comparison to PMs. In conclusion, this study shows that SIM–SOL dispersions can be successfully prepared using a solvent-free supercritical fluid process to enhance dissolution rate of the drug.

Considerations for the selection of co-formers in the preparation of co-amorphous formulations

Co-amorphous drug delivery systems are evolving as a credible alternative to amorphous solid dispersions technology. In Co-amorphous systems (CAMs), a drug is stabilized in amorphous form using small molecular weight compounds called as co-formers. A wide variety of small molecular weight co-formers have been leveraged in the preparation of CAMs. The stability and supersaturation potential of prepared co-amorphous phases largely depend on the type of co-former employed in the CAMs. However, the rationality behind the co-former selection in co-amorphous systems is poorly understood and scarcely compiled in the literature. There are various facets to the rational selection of co-former for CAMs. In this context, the present review compiles various factors affecting the co-former selection. The factors have been broadly classified under Thermodynamic, Kinetic and Pharmacokinetic-Pharmacologically relevant parameters. In particular, the importance of Glass transition, Miscibility, Liquid-Liquid phase separation (LLPS), Crystallization inhibition has been deliberated in detail.

Pharmaceutical nanoparticle isolation using CO2-assisted dynamic bed coating

Poor solubility of new chemical entities (NCEs) is a major bottleneck in the pharmaceutical industry which typically leads to poor drug bioavailability and efficacy. Nanotechnologies offer an interesting route to improve the apparent solubility and dissolution rate of pharmaceutical drugs, and processes such as nano-spray drying and supercritical CO₂-assisted spray drying (SASD) provide a route to engineer and produce solid drug nanoparticles. However, dried nanoparticles often show poor rheological properties (e.g. flowability, tabletability) and their isolation using these methods is typically inefficient and leads to poor collection yields. The work presented herein demonstrates a novel production and isolation method for drug nanoparticles using a 'top spray dynamic bed coating' process, which uses CO₂ spray as the fluidizing gas. Nanoparticles of three BCS class II Active Pharmaceutical Ingredients (APIs), namely carbamazepine (CBZ), ketoprofen (KET) and risperidone (RIS), were produced and successfully coated onto micron-sized microcrystalline cellulose (MCC) particles. The size distribution of the API nanoparticles was in the range of 90-490 nm. The stable forms of CBZ (form III), KET (form I), and the metastable form of RIS (form B) were produced and coated onto MCC carrier microparticles. All the isolated solids presented optimal rheological properties along with a 2-6 fold improvement in the dissolution rate of the corresponding APIs. Hence, the 'top spray dynamic bed coater' developed in this work demonstrates to be an efficient approach to produce and coat API nanoparticles onto carrier particles with optimal rheological properties and improved dissolution.

Overview of Extensively Employed Polymeric Carriers in Solid Dispersion Technology

Solid dispersion is the preferred technology to prepare efficacious forms of BCS class-II/IV APIs. To prepare solid dispersions, there exist a wide variety of polymeric carriers with interesting physicochemical and thermochemical characteristics available at the disposal of a formulation scientist. Since the advent of the solid dispersion technology in the early 1960s, there have been more than 5000 scientific papers published in the subject area. This review discusses the polymeric carrier properties of most extensively used polymers PVP, Copovidone, PEG, HPMC, HPMCAS, and Soluplus® in the solid dispersion technology. The literature trends about preparation techniques, dissolution, and stability improvement are analyzed from the Scopus® database to enable a formulator to make an informed choice of polymeric carrier. The stability and extent of dissolution improvement are largely dependent upon the type of polymeric carrier employed to formulate solid dispersions. With the increasing acceptance of transfer dissolution setup in the research community, it is required to evaluate the crystallization/precipitation inhibition potential of polymers under dynamic pH shift conditions. Further, there is a need to develop a regulatory framework which provides definition and complete classification along with necessarily recommended studies to characterize and evaluate solid dispersions.

Physical stability of amorphous pharmaceutical solids: Nucleation, crystal growth, phase separation and effects of the polymers

Compared to their crystalline forms, amorphous pharmaceutical solids present marvelous potential and advantages for effectively improving the oral bioavailability of poorly water-soluble drugs. A central issue in developing amorphous pharmaceutical solids is the stability against crystallization, which is particularly important for maintaining their advantages in solubility and dissolution rate. This review provides a comprehensive overview of recent studies focusing on the physical stability of amorphous pharmaceutical solids affected by nucleation, crystal growth, phase separation and the addition of polymers. Moreover, we highlight the novel technologies and theories in the field of amorphous pharmaceutical solids. Meanwhile, the challenges and strategies in maintaining the physical stability of amorphous pharmaceutical solids are also discussed. With a better understanding of physical stability, the more robust amorphous pharmaceutical formulations with desired pharmaceutical performance would be easier to achieve.

Formulation of co-amorphous systems from naproxen and naproxen sodium and in situ monitoring of physicochemical state changes during dissolution testing by Raman spectroscopy

Co-amorphous systems comprising low-molecular weight drugs and co-formers constitute an interesting approach to optimize pharmaceutical performance of drugs with low aqueous solubility. Within the different types of co-amorphous systems, the combination of a drug with its own salt may be an attractive formulation option due the absence of any inactive co-formers. The aim of this study was to investigate the possibility of forming a co-amorphous system from naproxen (NAP) and its sodium salt (NAP(Na)). Ball milling of NAP and NAP(Na) at equal molar ratio resulted in the formation of a co-amorphous system whilst NAP and NAP(Na) alone were crystalline following both, ball milling and melt quenching. Infrared spectroscopy and physical stability testing revealed that intermolecular interactions were able to maintain the ball milled NAP-NAP(Na) system amorphous for 2 months at 40 °C. Surprisingly, the dissolution rate of co-amorphous NAP-NAP(Na) was only intermediate between those of crystalline NAP and crystalline NAP(Na). In situ Raman spectroscopic measurements indicated an initial phase separation of the co-amorphous form to NAP and NAP(Na) followed by dissociation of sodium from NAP(Na) and crystallization to NAP. These findings contribute to the design of co-amorphous formulations with the combination of a drug and its own salt.

Albendazole solid dispersions prepared using PEG6000 and Poloxamer188: formulation, characterization and in vivo evaluation

This study aimed to optimize the preparation process of albendazole (ABZ) solid dispersion (SD) and enhance its dissolution rate and oral bioavailability in dogs. The ABZ-SD formulations were prepared by a fusion method with ABZ and polyethylene glycol 6000 (PEG 6000), poloxamer 188 (P 188) polymers at various weight ratios or the combination of PEG 6000&P 188. The characterizations of the optimal formulations were performed by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), in vitro dissolution test and molecular docking. The in vivo pharmacokinetic study was conducted in beagle dogs. As a result, ABZ solid dispersion based on PEG 6000&P 188 (1:2) was successfully prepared. The ABZ-SD formulation could significantly improve the apparent solubility and dissolution rate of ABZ compared with commercial tablets. Furthermore, the water solubility of ABZ-SD was improved mainly based on hydrogen bond association. Besides, at an oral dosage of 15 mg/kg ABZ, the SDs had higher Cmax values and areas under the curve (AUCs) compared to those of commercial ABZ tablets. Preparation of ABZ-loaded SDs by PEG 6000&P 188 is a promising strategy to improve the oral bioavailability of ABZ.

Copolymeric Micelles Overcome the Oral Delivery Challenges of Amphotericin B

Classified as a Biopharmaceutical Classification System (BCS) class IV drug, amphotericin B (AmB) has low aqueous solubility and low permeability leading to low oral bioavailability. To improve these limitations, this study investigated the potential of AmB-loaded polymeric micelles (AmB-PM) to increase intestinal absorption. AmB-PM were prepared with polyvinyl caprolactam–polyvinyl acetate–polyethylene glycol copolymer (Soluplus^®) as a polymeric carrier and used a modified solvent diffusion and microfluidics (NanoAssemblr^®) method. AmB-PM have a mean particle size of ~80 nm and are mono-disperse with a polydispersity index <0.2. The entrapment efficiency of AmB was up to 95% and achieved with a high drug loading up to ~20% (w/w) with a total amount of incorporated drug of 1.08 ± 0.01 mg/mL. Importantly, compared to free drug, AmB-PM protected AmB from degradation in an acidic (simulated gastric) environment. Viability studies in Caco-2 cells confirmed the safety/low toxicity of AmB-PM. In vitro cellular absorption studies confirmed that AmB-PM increased AmB uptake in Caco-2 cells 6-fold more than free AmB (i.e., 25% compared with 4% within 30 min). Furthermore, the permeability of AmB across Caco-2 monolayers was significantly faster (2-fold) and more pronounced for AmB-PM in comparison to free drug (3.5-fold increase). Thus, the developed AmB-PM show promise as a novel oral delivery system for AmB and justifies further investigation.

Stable amorphous solid dispersions of fenofibrate using hot melt extrusion technology: Effect of formulation and process parameters for a low glass transition temperature drug

Development of stable amorphous solid dispersions (ASDs) for a low glass transition temperature (Tg) drug is a challenging task. The physico-chemical properties of the drug and excipients play a critical role in developing stable ASDs. In this study, ASDs of poorly soluble fenofibrate, a drug with a low Tg, were formulated using hydroxy propyl methylcellulose acetate succinate (HPMCAS) via hot melt extrusion (HME). The feasible processing conditions were established at varying drug loads and processing temperatures. The prepared ASDs were characterized for crystallinity using differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). Fourier transform-infrared spectroscopy was performed to study the potential interactions. DSC and PXRD studies confirmed the amorphous state of fenofibrate in the prepared ASDs. A discriminative in vitro dissolution method was established to study the impact of HPMCAS grades on dissolution profile. The dissolution parameters such as dissolution efficiency, initial dissolution rate and mean dissolution rate, suggested improved dissolution characteristics compared to pure fenofibrate. Accelerated stability studies at 40 °C/75% RH showed preservation of the amorphous nature of fenofibrate in formulations with 15% drug load and in vitro drug release studies indicated similar release profiles (f2 >50). This study provides an insight into the formulation and processing of ASDs for poorly soluble drugs with low Tg.

A simple and low-energy method to prepare loratadine nanosuspensions for oral bioavailability improvement: preparation, characterization, and in vivo evaluation

The effervescent method, as a simple and effective technology to prepare nanosuspensions, has gained great attention. In this present research, loratadine (LTD) nanosuspensions were successfully prepared by the effervescent method using Soluplus as stabilizer to improve the bioavailability of LTD in vivo. The mean particle size was about 100 nm. And the LTD nanosuspensions were lyophilized for further study. The freeze-dried powders could be dissolved quickly, and the mean particle size remained almost unchanged after powders were re-dissolved. By transmission electron microscope (TEM), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and X-ray diffraction (X-RD), the characterizations of LTD nanosuspensions and freeze-dried powders were studied. Commercial tablets were used as the reference to investigate the dissolution behaviors in different release media and of bioavailability in vivo of LTD freeze-dried powders. The cumulative dissolution of the LTD freeze-dried powders was superior in different release media compared with commercial tables. In addition, for the evaluation of the bioavailability of LTD nanosuspensions, the LTD concentration in rat plasma was determined using LC-MS/MS method. The results showed that the AUC_0-24 and C_max of LTD freeze-dried powders were about 2.14- and 2.01-fold higher than those of commercial tablets. In short, the effervescent method has been successfully applied to the preparation of LTD nanosuspensions to improve the bioavailability of LTD in vivo with the advantage of low energy consumption. This simple technology also provides an idea for the preparation of the other nanosuspensions.

Exploring the Potential of Mesoporous Silica as a Carrier for Puerarin: Characterization, Physical Stability, and In Vivo Pharmacokinetics

The aim of this study was to evaluate the use of a novel porous silica carrier, AEROPERL^® 300 Pharma (AP), to improve the in vitro release and oral bioavailability of puerarin (PUE) in solid dispersions (SDs). PUE-AP SD formulations with different ratios of drug to silica (RDS) were prepared by the solvent method. The scanning electron microscopy (SEM) results indicated that the dispersion of PUE improved as the concentration of AP was increased. The differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results revealed that PUE mostly existed in an amorphous state in the SDs. The rate of drug dissolution from the SDs was significantly higher than that from the PUE powder (p < 0.05). The in vitro drug release percentage from the PUE-AP SDs increased as the RDS was reduced. The oral bioavailability of PUE from the SDs improved when using AP, as indicated by AUC_(0-∞), which was 2.05 and 2.01 times greater than that of the PUE (API) and PVP K30 SDs, respectively (p < 0.05). The drug content, in vitro release profiles, and the amorphous state of PUE in the PUE-AP SDs showed no significant changes after being stored at room temperature for 6 months or under accelerated conditions (40 ± 2°C, 75 ± 5% relative humidity) for 3 months. AP has a high pore volume, large specific surface area, excellent flowability, and hydrophilic properties, making it capable of improving the dissolution and bioavailability of poorly water-soluble drugs.

Solubility and bioavailability enhancement study of lopinavir solid dispersion matrixed with a polymeric surfactant - Soluplus

As a biopharmaceutical classification system Class IV drug, lopinavir (LPV) shows relatively poor water solubility and permeation in vivo. In the study, we developed novel solid dispersions (SD) of LPV to improve its bioavailability and to describe their overall behaviors. By employing solvent evaporation for a preliminary formulation screening, the SDs of LPV-polymer-sorbitan monolaurate (SBM, as the wetting agent) at 1:4:0.4 (w/w) dramatically enhanced the LPV dissolution in a non-sink medium, and then hot-melt extrusion (HME) was applied to improve the dissolution further. A hydrophilic polymer - Kollidon VA 64 (VA64) and a polymeric surfactant Soluplus were employed as matrix respectively in the optimized formulations. The dissolution profiles of extrudates were significantly higher than those of SDs prepared with solvent-evaporation method. It was attributed to the stronger intermolecular interactions between LPV and the polymers in the HME process, which was also supported by the stability analysis after 6 months storage under 25 °C/60% RH. The differential scanning calorimetry, fourier transform infrared spectroscopy and equilibrium studies showed VA64 only created hydrogen bonding (H-bond) with LPV, but Soluplus generated both H-bond and micelle thanks to its amphiphilic structure. In addition, the bioavailability of LPV in Soluplus matrixed extrudate was 1.70-fold of VA64 matrixed extrudate and 3.70-fold of LPV crystal. In situ permeability and Caco-2 cell transport studies revealed that Soluplus significantly enhanced the permeability of LPV through rat intestine and Caco-2 cell monolayers by P-glycoprotein (P-gp) inhibition. Herein, Soluplus matrixed extrudate improved the LPV bioavailability through three mechanisms: H-bond with LPV, micelle formation in water and P-gp inhibition in vivo. These unique advantages of Soluplus suggested it is a promising carrier for poorly water soluble drugs, especially the substrates of P-gp.

Liquid antisolvent precipitation: an effective method for ocular targeting of lutein esters

Background

Lutein ester (LE) is an important carotenoid fatty acid ester. It is a form in which lutein is present in nature and is produced by free non-esterification and fatty acid esterification. LE is one of the safe sources of lutein. Increasing lutein intake can prevent and treat age-related macular degeneration. In addition, it can effectively inhibit gastric cancer, breast cancer, and esophageal cancer. However, the poor aqueous solubility of LE has impeded its clinical applications.

Objective

The objective of this study was to prepare lutein ester nanoparticles (LE-NPs) by liquid antisolvent precipitation techniques to improve the bioavailability of LE in vivo and improve eye delivery efficiency.

Materials and methods

The physical characterization of LE-NPs was performed, and their in vitro dissolution rate, in vitro antioxidant capacity, in vivo bioavailability, tissue distribution, and ocular pharmacokinetics were studied and evaluated.

Results

The LE freeze-dried powder obtained under the optimal conditions possessed a particle size of ~164.1±4.3 nm. The physical characterization analysis indicated the amorphous form of LE-NPs. In addition, the solubility and dissolution rate of LE-NPs in artificial gastric juice were 12.75 and 9.65 times that of the raw LE, respectively. The bioavailability of LE-NPs increased by 1.41 times compared with that of the raw LE. The antioxidant capacity of LE-NPs was also superior to the raw LE. The concentration of lutein in the main organs of rats treated with the LE-NPs was higher than that in rats treated with the raw LE. The bioavailability of LE-NPs in rat eyeballs was found to be 2.34 times that of the original drug.

Conclusion

LE-NPs have potential application as a new oral pharmaceutical formulation and could be a promising eye-targeted drug delivery system.

Amphiphilic Copolymer of Polyhedral Oligomeric Silsesquioxane (POSS) Methacrylate for Solid Dispersion of Paclitaxel

Suitable polymers for the homogeneous formulation of drug/polymer mixtures should be selected to correct the structural and physicochemical nature with a rapid dissolution rate. This study aimed to evaluate a copolymer prepared by the radical polymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and a polyhedral oligomeric silsesquioxane (POSS) methacrylate bearing an ethyl (C₂H₅) group (MPC-ran-C₂H₅-POSS) as a carrier for the solid formulation of paclitaxel (PTX). A single-phase homogeneous formulation of PTX with the mixture of the MPC-ran-C₂H₅-POSS and polyvinylpyrrolidone (PVP) was prepared by a solvent method. The formulation of MPC-ran-C₂H₅-POSS/PVP/PTX enhanced the dissolution rate and the dissolved amount (approximately 90% within 40 min) without precipitation. The X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) analysis confirmed the presence of PTX as an amorphous state. The amphiphilic nature of the MPC-ran-C₂H₅-POSS contributed to enhancing the aqueous solubility of PTX. The new formulation is applicable for solid dispersion technique via the supersaturation of PTX in an aqueous media.

Preparation, optimisation, and in vitro-in vivo evaluation of febuxostat ternary solid dispersion

The research aimed to prepare febuxostat (FEB) solid dispersion through solvent evaporation. Optimised solid dispersion composed of FEB, polyvinylpyrrolidone (PVP K30) and poloxamer at a ratio of 1:3:3 was characterised. Powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC) indicated FEB was transformed from crystalline into the amorphous state in solid dispersion and scanning electron microscopy (SEM) revealed the morphology. Fourier transform infrared spectroscopy (FT-IR) suggested the interactions formed between FEB and polymers. A remarkable increase was observed of the optimised formulation in saturation solubility, dissolution studies (96.17 ± 0.79% in pH 6.0), and bioavailability (C_max 18.25 ± 2.44 vs. 7.72 ± 0.48 μg/mL and AUC_0-∞ 53.62 ± 7.63 vs. 34.76 ± 2.45 μg·h/mL). Besides, the FEB solid dispersion showed great stability after 90 days storage. Thus, the present study supports the rationality of PVP K30 and poloxamer188 as co-carriers for the preparation of FEB solid dispersion.

Preparation, characterization and in vitro and in vivo evaluation of a solid dispersion of Naringin

Naringin (NA) is one of typical flavanone glycosides widely distributed in nature and possesses several biological activities including antioxidant, anti-inflammatory, and antiapoptotic. The aim of this study was to develop solid dispersion (SD) and to improve the dissolution rate and oral bioavailability of NA. NA-SD was prepared by the traditional preparation methods using PEG6000, F68, or PVP K30 as carrier at different drug to carrier ratios. According to the results of solubility and in vitro dissolution test, the NA-PEG6000 (1:3) SD was considered as an optimal formulation to characterize by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry and powder X-ray diffraction. Furthermore, oral bioavailabilities of NA-PEG6000 (1:3) SD and NA-suspension with the same dosage were investigated in SD rats. The results confirmed the formation of SD and the pharmacokinetic parameters of NA-PEG6000 (1:3) SD (C_max = 0.645 ± 0.262 µg/ml, AUC_0-t = 0.471 ± 0.084 µg/ml h) were higher than that of NA-suspension (C_max = 0.328 ± 0.183 µg/ml, AUC_0-t  = 0.361 ± 0.093 µg/ml h). Based on the results, the SD is considered as a promising approach to enhance the dissolution rate and oral bioavailability of NA.

Analysis of the Literature and Patents on Solid Dispersions from 1980 to 2015

Background: Solid dispersions are an effective formulation technique to improve the solubility, dissolution rate, and bioavailability of water-insoluble drugs for oral delivery. In the last 15 years, increased attention was focused on this technology. There were 23 marketed drugs prepared by solid dispersion techniques. Objective: This study aimed to report the big picture of solid dispersion research from 1980 to 2015. Method: Scientific knowledge mapping tools were used for the qualitative and the quantitative analysis of patents and literature from the time and space dimensions. Results: Western Europe and North America were the major research areas in this field with frequent international cooperation. Moreover, there was a close collaboration between universities and industries, while research collaboration in Asia mainly existed between universities. The model drugs, main excipients, preparation technologies, characterization approaches and the mechanism involved in the formulation of solid dispersions were analyzed via the keyword burst and co-citation cluster techniques. Integrated experimental, theoretical and computational tools were useful techniques for in silico formulation design of the solid dispersions. Conclusions: Our research provided the qualitative and the quantitative analysis of patents and literature of solid dispersions in the last three decades.

Predictive Modeling of Micellar Solubilization by Single and Mixed Nonionic Surfactants

Micellar solubilization is an important concept in the delivery of poorly water-soluble drugs. The rational selection of the type and the amount of surfactant to be incorporated in a formulation require comprehensive solubility studies. These studies are time and material demanding, both of which are scarce, especially during late discovery and early development stages. We hypothesized that, if the solubilization mechanism or molecular interaction is similar, the solubilization capacity ratio (a newly defined parameter) is dictated by micellar structures, independent of drugs. We tested this hypothesis by performing solubility studies using 8 commonly used nonionic surfactants and 17 insoluble compounds with diverse characteristics. The results show a striking constant solubilization capacity ratio among the 8 nonionic surfactants, which allow us to develop predictive solubility models for both single and mixed surfactant systems. The vast majority of the predicted solubility values, using our developed models, fall within 2-fold of the experimentally determined values with high correlation coefficients. As expected, systems involving ionic surfactant sodium dodecyl sulfate, used as a negative control, do not follow this trend. Deviations from the model, observed in this study or envisioned, were discussed. In conclusion, we have established predictive models that are capable of predicting solubility in a wide range of nonionic micellar solutions with only 1 experimental measurement. The application of such a model will significantly reduce resource and greatly enhance drug product development efficiency.

Melt extrusion with poorly soluble drugs - An integrated review

Over the last few decades, hot melt extrusion (HME) has emerged as a successful technology for a broad spectrum of applications in the pharmaceutical industry. As indicated by multiple publications and patents, HME is mainly used for the enhancement of solubility and bioavailability of poorly soluble drugs. This review is focused on the recent reports on the solubility enhancement via HME and provides an update for the manufacturing/scaling up aspects of melt extrusion. In addition, drug characterization methods and dissolution studies are discussed. The application of process analytical technology (PAT) tools and use of HME as a continuous manufacturing process may shorten the drug development process; as a result, the latter is becoming the most widely utilized technique in the pharmaceutical industry. The advantages, disadvantages, and practical applications of various PAT tools such as near and mid-infrared, ultraviolet/visible, fluorescence, and Raman spectroscopies are summarized, and the characteristics of other techniques are briefly discussed. Overall, this review also provides an outline for the currently marketed products and analyzes the strengths, weaknesses, opportunities and threats of HME application in the pharmaceutical industry.

Factors Affecting the Dissolution of Indomethacin Solid Dispersions

The aim of this study was to investigate the influence of factors such as carrier type, drug/carrier ratio, binary carriers, and preparation method on the dissolution of an insoluble drug, indomethacin (IM), under supersaturation conditions. Using a solvent evaporation (SE) method, poloxamer 188 and PVP K30 showed better dissolution among the selected carriers. Furthermore, as the ratio of carriers increased (drug/carrier ratio from 1:0.5 to 1:2), the dissolution rate increased especially in almost two times poloxamer 188 solid dispersions (SDs), while the reverse results were observed for PVP K30 SDs. For the binary carrier SD, a lower dissolution was found. Under hot melt extrusion (HME), the dissolution of poloxamer 188 SD and PVP K30 SD was 0.83- and 0.94-folds lower than that using SE, respectively, while the binary carrier SD showed the best dissolution. For poloxamer 188 SDs, the drug's crystal form changed when using SE, while no crystal form change was observed using HME. IM was amorphous in PVP K30 SDs prepared by both methods. For binary carrier systems, amorphous and crystalline drugs coexisted in SD using SE, and negligible amorphous IM was in SD using HME. This study indicated that a higher amorphous proportion in SD did not correlate with higher dissolution rate, and other factors, such as carrier type, particle size, and density, were also critical.

Clinical pharmacokinetics of an amorphous solid dispersion tablet of elacridar

Elacridar is an inhibitor of the permeability glycoprotein (P-gp) and the breast cancer resistance protein (BCRP) and is a promising absorption enhancer of drugs that are substrates of these drug-efflux transporters. However, elacridar is practically insoluble in water, resulting in low bioavailability which currently limits its clinical application. We evaluated the in vitro dissolution and clinical pharmacokinetics of a novel amorphous solid dispersion (ASD) tablet containing elacridar. The dissolution from ASD tablets was compared to that from a crystalline powder mixture in a USP type II dissolution apparatus. The pharmacokinetics of the ASD tablet were evaluated in an exploratory clinical study at oral doses of 25, 250, or 1000 mg in 12 healthy volunteers. A target C_max was set at ≥ 200 ng/mL based on previous clinical data. The in vitro dissolution from the ASD tablet was 16.9 ± 3.7 times higher compared to that from a crystalline powder mixture. C_max and AUC_0-∞ increased linearly with dose over the explored range. The target C_max of ≥ 200 ng/mL was achieved at the 1000-mg dose level. At this dose, the C_max and AUC_0-∞ were 326 ± 67 ng/mL and 13.4 ± 8.6 · 10³ ng · h/mL, respectively. In summary, the ASD tablet was well tolerated, resulted in relevant pharmacokinetic exposure, and can be used for proof-of-concept clinical studies.

Downstream drug product processing of itraconazole nanosuspension: Factors influencing tablet material properties and dissolution of compacted nanosuspension-layered sugar beads

There has been limited research done on the downstream processing of nanosuspensions into solid oral dosage forms. This paper demonstrates the bead layering process with a layering level at 150% and 240%, as well as the selection and justification of the outer phase excipients for tabletability and disintegrating properties. In a previous study, an itraconazole nanosuspension stabilised by SDS and HPMC E5 was layered onto sugar beads with coating polymer HPMC VLV. In the current study, compression studies with these layered beads utilising the small bead size at 150% or 240% layering levels with outer phase cushioning excipients MCC, copovidone or isomalt were performed. Other excipients such as co-compressed crospovidone-PEG 4000; DCP functioning as a disintegrant; and HPC as a binder was also added. Target output variables were achieved with a balance between an adequate tensile strength and fast dissolution rate with a release of 99.0% (±1.0% SD) within 10min, which is in accordance with the FDA guidance for dissolution testing. The results show that the compaction of nanosuspension-layered beads is a suitable process for processing an itraconazole nanosuspension into a solid dosage form such as a compacted tablet without compromising on drug release.

Pharmaceutical development of an amorphous solid dispersion formulation of elacridar hydrochloride for proof-of-concept clinical studies

OBJECTIVE

A novel tablet formulation containing an amorphous solid dispersion (ASD) of elacridar hydrochloride was developed with the purpose to resolve the drug's low solubility in water and to conduct proof-of-concept clinical studies.

SIGNIFICANCE

Elacridar is highly demanded for proof-of-concept clinical trials that study the drug's suitability to boost brain penetration and bioavailability of numerous anticancer agents. Previously, clinical trials with elacridar were performed with a tablet containing elacridar hydrochloride. However, this tablet formulation resulted in poor and unpredictable absorption which was caused by the low aqueous solubility of elacridar hydrochloride.

METHODS

Twenty four different ASDs were produced and dissolution was compared to crystalline elacridar hydrochloride and a crystalline physical mixture. The formulation with highest dissolution was characterized for amorphicity. Subsequently, a tablet was developed and monitored for chemical/physical stability for 12 months at +15-25 °C, +2-8 °C and -20 °C.

RESULTS

The ASD powder was composed of freeze dried elacridar hydrochloride-povidone K30-sodium dodecyl sulfate (1:6:1, w/w/w), appeared fully amorphous and resulted in complete dissolution whereas crystalline elacridar hydrochloride resulted in only 1% dissolution. The ASD tablets contained 25 mg elacridar hydrochloride and were stable for at least 12 months at -20 °C.

CONCLUSIONS

The ASD tablet was considered feasible for proof-of-concept clinical studies and is now used as such.

Inventory of oral anticancer agents: Pharmaceutical formulation aspects with focus on the solid dispersion technique

Dissolution from the pharmaceutical formulation is a prerequisite for complete and consistent absorption of any orally administered drug, including anticancer agents (oncolytics). Poor dissolution of an oncolytic can result in low oral bioavailability, high variability in blood concentrations and with that suboptimal or even failing therapy. This review discusses pharmaceutical formulation aspects and absorption pharmacokinetics of currently licensed orally administered oncolytics. In nearly half of orally dosed oncolytics poor dissolution is likely to play a major role in low and unpredictable absorption. Dissolution-limited drug absorption can be improved with a solid dispersion which is a formulation method that induces super-saturated drug dissolution and with that it enhances in vivo absorption. This review discusses formulation principles with focus on the solid dispersion technology and how it works to enhance drug absorption. There are currently three licensed orally dosed oncolytics formulated as a solid dispersion (everolimus, vemurafenib and regorafenib) and these formulations result in remarkably improved dissolution and absorption compared to what can be achieved with conventional formulations of the respective oncolytics. Because of the successful implementation of these three solid dispersion formulations, we encourage the application of this formulation method for poorly soluble oral oncolytics.

Pharmaceutical development of an oral tablet formulation containing a spray dried amorphous solid dispersion of docetaxel or paclitaxel

Previously, it was shown in Phase I clinical trials that solubility-limited oral absorption of docetaxel and paclitaxel can be drastically improved with a freeze dried solid dispersion (fdSD). These formulations, however, are unfavorable for further clinical research because of limitations in amorphicity of SD and scalability of the production process. To resolve this, a spray drying method for an SD (spSD) containing docetaxel or paclitaxel and subsequently drug products were developed. Highest saturation solubility (Smax), precipitation onset time (Tprecip), amorphicity, purity, residual solvents, yield/efficiency and powder flow of spSDs were studied. Drug products were monitored for purity/content and dissolution during 24 months at +15-25°C. Docetaxel spSD Smax was equal to that of fdSD but Tprecip was 3 times longer. Paclitaxel spSD Smax was 30% increased but Tprecip was equal to fdSD. spSDs were fully amorphous, >99% pure, <5% residual solvents, mean batch yield was 100g and 84%. spSDs had poor powder flow characteristics, which could not be resolved by changing settings, but by using 75% lactose as diluent. The drug product was a tablet with docetaxel or paclitaxel spSD and was stable for at least 24 months. Spray drying is feasible for the production of SD of docetaxel or paclitaxel for upcoming clinical trials.