Classification of orally administered drugs on the World Health Organization Model list of Essential Medicines according to the biopharmaceutics classification system

Mechanochemical Synthesis of New Praziquantel Cocrystals: Solid-State Characterization and Solubility

New cocrystals of praziquantel with suberic, 3-hydroxybenzoic, benzene-1,2,4,5-tetracarboxylic, trimesic, and 5-hydroxyisophthalic acids were obtained through ball milling experiments. The optimal conditions for the milling process were chosen by changing the solvent volume and the mechanical action time. Supramolecular interactions in the new cocrystals are detailed based on single-crystal X-ray diffraction analysis, confirming the expected formation of hydrogen bonds between the praziquantel carbonyl group and the carboxyl (or hydroxyl) moieties of the coformers. Different structural characterization techniques were performed for all samples, but the praziquantel:suberic acid cocrystal includes a wider range of investigations such as thermal analysis, infrared and X-ray photoelectron spectroscopies, and SEM microscopy. The stability for up to five months was established by keeping it under extreme conditions of temperature and humidity. Solubility studies were carried out for all the new forms disclosed herein and compared with the promising cocrystals previously reported with salicylic, 4-aminosalicylic, vanillic, and oxalic acids. HPLC analyses revealed a higher solubility for most of the new cocrystal forms, as compared to pure praziquantel.

Medication use in a cohort of adults with chronic intestinal failure: A prospective cross-sectional study

BACKGROUND

Oral drug therapy may be compromised in chronic intestinal failure (IF) because of alterations in absorption and transit. Only scarce literature is available on which medication patients with chronic IF take in daily life. The aim was to describe the medication use in these patients.

METHODS

A medication history was obtained from adults with chronic IF treated in our tertiary care IF center. Degree of polypharmacy, drug classes, Biopharmaceutics Classification System classes, route of administration, and formulation of drugs were analyzed.

RESULTS

From October 2019 until December 2020, 72 patients (35 patients with short bowel syndrome [SBS] and 37 patients without SBS) were included. Polypharmacy was seen in 85.7% of patients with SBS and 75.7% of patients without SBS. The top three drug classes were proton-pump inhibitors, vitamin D or acetaminophen, and antimotility medication or laxatives/benzodiazepines. Approximately 25% of the drugs were classified as Biopharmaceutics Classification System class I drugs. In patients with SBS (78%) and patients without SBS (74.9%), most medication was taken orally, requiring gastrointestinal absorption of the active substance to be pharmacologically active. Most of these medications (77% in patients with SBS and 80.8% in patients without SBS) were formulated as a capsule or tablet, requiring disintegration and dissolution in the gastrointestinal tract before absorption can take place.

CONCLUSION

Polypharmacy was observed in most patients with chronic IF. Most medication was taken orally in formulations requiring disintegration, dissolution, and gastrointestinal absorption, which could be compromised in chronic IF.

Pharmacokinetics of oral ciprofloxacin in adult patients: A scoping review

AIMS

To map the literature on oral ciprofloxacin's pharmacokinetics and its implications for dose adjustments in specific populations.

METHODS

A scoping review was performed according to the Cochrane Collaboration and JBI and reported following the PRISMA-ScR. Systematic searches on electronic databases were conducted to integrate the current evidence on ciprofloxacin's pharmacokinetics. The quality of the included studies was assessed using ClinPK's checklist.

RESULTS

The search yielded 55 relevant studies. Within the traditional pharmacokinetics studies (n = 46), 86 profiles were examined (72 involving healthy patients and 14 with various clinical conditions). Oral ciprofloxacin's pharmacokinetics were influenced by covariates such as drug interactions (ferrous ions, calcium carbonate, diclofenac and itraconazole), food interactions (calcium-rich foods), elderly populations and renal impairment. Notably, variability in pharmacokinetic parameters existed among subjects, regardless of their health status, underscoring the need for comprehensive population descriptions. Population pharmacokinetic studies (n = 9) identified significant covariates for hospitalized patients, such as creatinine clearance, plasma bicarbonate, estimated glomerular filtration rate, renal replacement therapy, age, sex, total bilirubin, fat-free mass, dietary factors in renal disease, rifampicin for clearance models and body weight for volume of distribution models. Most pharmacokinetic/pharmacodynamic assessments concluded that 1200 mg/day provides a high probability of target attainment for bacteria with minimum inhibitory concentration <0.5 mg L-1 , aiming for an area under the curve for 24 h/minimum inhibitory concentration >125 h.

CONCLUSIONS

This study offers a comprehensive overview regarding oral ciprofloxacin's pharmacokinetics across various health conditions. It highlights the complexities of ciprofloxacin's pharmacokinetics, emphasizing the importance of considering multiple factors in dose adjustments.

Evaluating physiochemical properties of FDA-approved orally administered drugs

INTRODUCTION

Analyses of orally administered FDA-approved drugs from 1990 to 1993 enabled the identification of a set of physiochemical properties known as Lipinski's Rule of Five (Ro5). The original Ro5 and extended versions still remain the reference criteria for drug development programs. Since many bioactive compounds do not conform to the Ro5, we validated the relevance of and adherence to these rulesets in a contemporary cohort of FDA-approved drugs.

AREAS COVERED

The authors noted that a significant proportion of FDA-approved orally administered parent compounds from 2011 to 2022 deviate from the original Ro5 criteria (~38%) or the Ro5 with extensions (~53%). They then evaluated if a contemporary Ro5 criteria (cRo5) could be devised to better predict oral bioavailability. Furthermore, they discuss many case studies showcasing the need for and benefit of increasing the size of certain compounds and cover several evolving strategies for improving oral bioavailability.

EXPERT OPINION

Despite many revisions to the Ro5, the authors find that no single proposed physiochemical rule has universal concordance with absolute oral bioavailability. Innovations in drug delivery and formulation have dramatically expanded the range of physicochemical properties and the chemical diversity for oral administration.

Quantitative analysis and evaluation of solid-state stability of mebendazole Forms A and C suspensions by powder X-ray diffraction using the Rietveld method

Mebendazole (MBZ) is a broad-spectrum active pharmaceutical ingredient (API) indicated for treating parasitosis, and it has three solid-state forms, A, B, and C. These solid forms exhibit significant differences in dissolution properties, which cause considerable changes in the therapeutic effect. When at least 30 % of Form A is present in the formulation, it has a similar effect to the placebo. The aim of this study was to develop a reliable quantitative method for MBZ (Forms A and C) suspensions that allowed to study the solid-state stability and the kinetics of the solid-state transformation of MBZ suspensions under the recommended pharmaceutical industry conditions. One method was developed to carry out the drying process and the other one to quantify Forms A and C of MBZ suspensions; both were evaluated. For the stability study, samples were prepared with different starting reference concentrations of Form A and stored from 1 to 24 months under long-term stability conditions (30 ± 2 °C and 75 ± 5 % RH) and from 1 to 6 months under accelerated stability conditions (40 ± 2 °C and 75 ± 5 % RH). Data collection was performed by powder X-ray diffraction (PXRD). The Rietveld method (RM) and Topas's program were used to solid form quantification. Avrami's equation was used to determine the kinetic parameters. The results showed that the combination of the drying process and solid form quantification developed method for suspension was a very accurate methodology for solid-state stability studies. Furthermore, in long-term and accelerated solid-state conditions, suspension with an initial value of 1 % of Form A were sufficient to cause a solid-state transformation (Form C to A) greater than 30 % in the first and second months, with a complete transformation in nine and six months respectively. These results demonstrate that suspensions show complete solid-state transformation (Form C to A) in a shorter time than the product's shelf life (∼2 years). In this work, a reliable methodology was developed to quantify MBZ (Forms A and C) suspensions. This methodology could be used to control the different solid forms for MBZ and other APIs to avoid solid-state transformation problems.

Evaluation of dapsone and its synthetic derivative DDS‑13 in cancer in vitro

The present study highlighted the repositioning of the drug dapsone (DDS) for cancer therapy. Due to its mechanism of action, DDS has a dual effect as an antibiotic and as an anti-inflammatory/immunomodulator; however, at high doses, it has important adverse effects. The derivative DDS-13 [N,N'-(sulfonyl bis (4,1-phenylene)) dioctanamide] was synthesized through an N-acylation reaction to compare it with DDS. Its cytotoxic effects in cancer cells (DU145 and HeLa) and non-cancer cells (HDFa) were observed at concentrations ranging 0.01-100 µM and its physicochemical/pharmacokinetic properties were analyzed using the SwissADME tool. The objectives of the present study were to evaluate the anticancer activity of both DDS and DDS-13 and to identify the physicochemical and pharmacokinetic properties of DDS-13. The results showed that DDS-13 presented a cytotoxic effect in the DU145 cell line (IC50=19.06 µM), while DDS showed a cytotoxic effect on both the DU145 (IC50=11.11 µM) and HeLa (IC50=13.07 µM) cell lines. DDS-13 appears to be a good cytotoxic candidate for the treatment of prostate cancer, while DDS appears to be a good candidate for both cervical and prostate cancer. Neither candidate showed a cytotoxic effect in non-cancerous cells. The different pharmacokinetic properties of DDS-13 make it a new candidate for evaluation in preclinical models for the treatment of cancer.

Praziquantel Fifty Years on: A Comprehensive Overview of Its Solid State

This review discusses the entire progress made on the anthelmintic drug praziquantel, focusing on the solid state and, therefore, on anhydrous crystalline polymorphs, amorphous forms, and multicomponent systems (i.e., hydrates, solvates, and cocrystals). Despite having been extensively studied over the last 50 years, new polymorphs and the greater part of their cocrystals have only been identified in the past decade. Progress in crystal engineering science (e.g., the use of mechanochemistry as a solid form screening tool and more strategic structure-based methods), along with the development of analytical techniques, including Synchrotron X-ray analyses, spectroscopy, and microscopy, have furthered the identification of unknown crystal structures of the drug. Also, computational modeling has significantly contributed to the prediction and design of new cocrystals by considering structural conformations and interactions energy. Whilst the insights on praziquantel polymorphs discussed in the present review will give a significant contribution to controlling their formation during manufacturing and drug formulation, the detailed multicomponent forms will help in designing and implementing future praziquantel-based functional materials. The latter will hopefully overcome praziquantel's numerous drawbacks and exploit its potential in the field of neglected tropical diseases.

Rapid Study on Mefloquine Hydrochloride Complexation with Hydroxypropyl-β-Cyclodextrin and Randomly Methylated β-Cyclodextrin: Phase Diagrams, Nuclear Magnetic Resonance Analysis, and Stability Assessment

This study investigates the complexation of mefloquine hydrochloride by cyclodextrins to improve its solubility in order to design an oral solution. This approach may enhance the effectiveness of mefloquine, a drug which can be used for malaria prophylaxis and treatment in children. Mefloquine hydrochloride's solubility was assessed in different buffer solutions, and its quantification was achieved through high-performance liquid chromatography. The complexation efficiency with cyclodextrins was evaluated, and nuclear magnetic resonance (NMR) methods were employed to determine the interactions between mefloquine and cyclodextrins. Mefloquine's solubility increased when combined with hydroxypropyl-β-cyclodextrin (HP-β-CD) and randomly methylated β-cyclodextrin (RAMEB), with RAMEB being more effective. The drug's solubility varied across different pH buffers, being higher in acidic buffers. Interestingly, mefloquine's solubility decreased with a citrate buffer, possibly due to precipitation. The NMR studies highlighted non-covalent interactions between RAMEB, HP-β-CD, and mefloquine, explaining the solubilizing effect via complexation phenomena. Furthermore, the NMR experiments indicated the complexation of mefloquine by all the studied cyclodextrins, forming diastereoisomeric complexes. Cyclodextrin complexation improved mefloquine's solubility, potentially impacting its bioavailability.

Battle of the milky way: Lymphatic targeted drug delivery for pathogen eradication

Many viruses, bacteria, and parasites rely on the lymphatic system for survival, replication, and dissemination. While conventional anti-infectives can combat infection-causing agents in the bloodstream, they do not reach the lymphatic system to eradicate the pathogens harboured there. This can result in ineffective drug exposure and reduce treatment effectiveness. By developing effective lymphatic delivery strategies for antiviral, antibacterial, and antiparasitic drugs, their systemic pharmacokinetics may be improved, as would their ability to reach their target pathogens within the lymphatics, thereby improving clinical outcomes in a variety of acute and chronic infections with lymphatic involvement (e.g., acquired immunodeficiency syndrome, tuberculosis, and filariasis). Here, we discuss approaches to targeting anti-infective drugs to the intestinal and dermal lymphatics, aiming to eliminate pathogen reservoirs and interfere with their survival and reproduction inside the lymphatic system. These include optimized lipophilic prodrugs and drug delivery systems that promote lymphatic transport after oral and dermal drug intake. For intestinal lymphatic delivery via the chylomicron pathway, molecules should have logP values >5 and long-chain triglyceride solubilities >50 mg/g, and for dermal lymphatic delivery via interstitial lymphatic drainage, nanoparticle formulations with particle size between 10 and 100 nm are generally preferred. Insight from this review may promote new and improved therapeutic solutions for pathogen eradication and combating infective diseases, as lymphatic system involvement in pathogen dissemination and drug resistance has been neglected compared to other pathways leading to treatment failure.

Strategies to Enhance the Solubility and Bioavailability of Tocotrienols Using Self-Emulsifying Drug Delivery System

Tocotrienols have higher medicinal value, with multiple sources of evidence showing their biological properties as antioxidant, anti-inflammatory, and osteoprotective compounds. However, tocotrienol bioavailability presents an ongoing challenge in its translation into viable products. This is because tocotrienol oil is known to be a poorly water-soluble compound, making it difficult to be absorbed into the body and resulting in less effectiveness. With the potential and benefits of tocotrienol, new strategies to increase the bioavailability and efficacy of poorly absorbed tocotrienol are required when administered orally. One of the proposed formulation techniques was self-emulsification, which has proven its capacity to improve oral drug delivery of poorly water-soluble drugs by advancing the solubility and bioavailability of these active compounds. This review discusses the updated evidence on the bioavailability of tocotrienols formulated with self-emulsifying drug delivery systems (SEDDSs) from in vivo and human studies. In short, SEDDSs formulation enhances the solubility and passive permeability of tocotrienol, thus improving its oral bioavailability and biological actions. This increases its medicinal and commercial value. Furthermore, the self-emulsifying formulation presents a useful dosage form that is absorbed in vivo independent of dietary fats with consistent and enhanced levels of tocotrienol isomers. Therefore, a lipid-based formulation technique can provide an additional detailed understanding of the oral bioavailability of tocotrienols.

Study on Sulfamethoxazole-Piperazine Salt: A Mechanistic Insight into Simultaneous Improvement of Physicochemical Properties

Multidrug salts represent more than one drug in a crystal lattice and thus could be used to deliver multiple drugs in a single dose. It showcases unique physicochemical properties in comparison to individual components, which could lead to improved efficacy and therapeutic synergism. This study presents the preparation and scale-up of sulfamethoxazole-piperazine salt, which has been thoroughly characterized by X-ray diffraction and thermal and spectroscopic analyses. A detailed mechanistic study investigates the impact of piperazine on the microenvironmental pH of the salt and its effect on the speciation profile, solubility, dissolution, and diffusion profile. Also, the improvement in the physicochemical properties of sulfamethoxazole due to the formation of salt was explored with lattice energy contributions. A greater ionization of sulfamethoxazole (due to pH changes contributed by piperazine) and lesser lattice energy of sulfamethoxazole-piperazine contributed to improved solubility, dissolution, and permeability. Moreover, the prepared salt addresses the stability issues of piperazine and exhibits good stability behavior under accelerated stability conditions. Due to the improvement of physicochemical properties, the sulfamethoxazole-piperazine salt demonstrates better pharmacokinetic parameters in comparison to sulfamethoxazole and provides a strong suggestion for the reduction of dose. The following study suggests that multidrug salts can concurrently enhance the physicochemical properties of drugs and present themselves as improved fixed-dose combinations.

Praziquantel meets Niclosamide: A dual-drug Antiparasitic Cocrystal

In this paper we report a successful example of combining drugs through cocrystallization. Specifically, the novel solid is formed by two anthelminthic drugs, namely praziquantel (PZQ) and niclosamide (NCM) in a 1:3 molar ratio, and it can be obtained through a sustainable one-step mechanochemical process in the presence of micromolar amounts of methanol. The novel solid phase crystallizes in the monoclinic space group of P21/c, showing one PZQ and three NCM molecules linked through homo- and heteromolecular hydrogen bonds in the asymmetric unit, as also attested by SSNMR and FT-IR results. A plate-like habitus is evident from scanning electron microscopy analysis with a melting point of 202.89 °C, which is intermediate to those of the parent compounds. The supramolecular interactions confer favorable properties to the cocrystal, preventing NCM transformation into the insoluble monohydrate both in the solid state and in aqueous solution. Remarkably, the PZQ - NCM cocrystal exhibits higher anthelmintic activity against in vitro S. mansoni models than corresponding physical mixture of the APIs. Finally, due to in vitro promising results, in vivo preliminary tests on mice were also performed through the administration of minicapsules size M.

Effect of the Similarity of Formulations and Excipients of Approved Generic Drug Products on In Vivo Bioequivalence for Putative Biopharmaceutics Classification System Class III Drugs

One of the potential essential factors that restricts generic industry from applying the Biopharmaceutics Classification System (BCS) Class III biowaiver is adherence to the stringent formulation criteria for formulation qualitative (Q1) sameness and quantitative (Q2) similarity. The present study has investigated formulations and excipients from 16 putative BCS Class III drug substances in a total of 19 drug products via 133 approved abbreviated new drug applications (ANDAs) containing in vivo bioequivalence (BE) studies in human subjects during the time period from 2006 to 2022. We included the BCS Class III drugs in this study by referring to published literature, the World Health Organization (WHO) BCS Class I-IV list, FDA internal assessments, and physicochemical properties (high solubility and low permeability) of specific drug substances. Based upon all 133 approved generic formulations in this study, the highest amount of each different compendial excipient with a total of 40 is defined as its corresponding typical amount that has not shown any potential impact on in vivo drug absorption. In the present study, although only 30.08% of the investigated generic formulations met Q1 the same/Q2 similar formulation criteria for the BCS Class III biowaiver, and while approximately 69.92% failed to meet those criteria with non-Q1/Q2 similar formulations, all test/reference ratios (T/R) and 90% confidence intervals for all instrumental PK parameters (AUC0-t, AUC0-inf, and Cmax) met the bioequivalence (BE) criteria (80-125%). The results of formulation assessment suggest that the commonly used excipients without atypical amounts did not impact absorption of 16 putative BCS Class III drug substances. The rate and extent of absorption of drugs appears to be more dependent upon the biopharmaceutic and physiochemical properties of BCS Class III drug substance and less, or not dependent upon their formulations, excipients, and the excipients class. Our findings may lead to a more flexible formulation design space regarding the stringent BCS Class III formulation criteria.

Solubility of lamotrigine in age-specific biorelevant media that simulated the fasted- and fed-conditions of the gastric and intestinal environments in pediatrics and adults: implications for traditional, re-formulated, modified, and new oral formulations

BACKGROUND

Lamotrigine is an effective antiseizure medication that can be used in the management of focal and generalized epilepsies in pediatric patients. This study was conducted to quantify and compare the solubility of lamotrigine in age-specific biorelevant media that simulated the fasted and fed conditions of the gastric and intestinal environments in pediatrics and adults. Another aim was to predict how traditional, re-formulated, modified, and new oral formulations would behave in the gastric and intestinal environments across different age groups.

METHODS

Solubility studies of lamotrigine were conducted in 16 different age-specific biorelevant media over the pH range and temperature specified by the current biopharmaceutical classification system-based criteria. The age-specific biorelevant media simulated the environments in the stomach and proximal gastrointestinal tract in both fasted and fed conditions of adults and pediatric sub-populations. The solubility of lamotrigine was determined using a pre-validated HPLC-UV method.

RESULTS

Lamotrigine showed low solubility in the 16 age-specific biorelevant media as indicated by a dose number of > 1. There were significant age-specific variabilities in the solubility of lamotrigine in the different age-specific biorelevant media. Pediatric/adult solubility ratios of lamotrigine fell outside the 80-125% range in 6 (50.0%) and were borderline in 3 (25.0%) out of the 12 compared media. These ratios indicated that the solubility of lamotrigine showed considerable differences in 9 out of the 12 (75.0%) of the compared media.

CONCLUSION

Future studies are still needed to generate more pediatric biopharmaceutical data to help understand the performances of oral dosage forms in pediatric sub-populations.

Metoclopramide loaded buccal films for potential treatment of migraine symptoms: in vitro and in vivo study

OBJECTIVE

Developing mucoadhesive buccal films loaded with metoclopramide for the treatment of migraine-associated vomiting.

METHODS

Buccal films were prepared using the solvent casting method. Several tests were conducted, including measurement of film weight, thickness, drug content, moisture uptake, swelling index, and DSC analysis. The bioadhesion properties were also assessed. Furthermore, in vitro release profiles and in human bioavailability were studied.

RESULTS

The developed films were transparent, homogeneous, and easy to remove. Film weight and thickness increased with higher drug content. The drug entrapment exceeded 90%. Film weight increased with moisture uptake, and DSC analysis indicated the absence of drug crystallinity. Bioadhesion properties and swelling index decreased with increasing drug content. In vitro release demonstrated that drug release depended on the drug-polymer ratio. The in vivo study showed significant improvements in Tmax (from 1.21 ± 0.33 to 0.50 ± 0.0) and Cmax (from 45.29 ± 14.66 to 63.27 ± 24.85) compared to conventional tablets.

CONCLUSION

The prepared mucoadhesive buccal films exhibited the desired characteristics and demonstrated enhanced drug absorption, evidenced by the significantly reduced Tmax and increased Cmax compared to conventional tablets. The results indicate the successful achievement of the study objectives in selecting and designing an effective pharmaceutical dosage form. as cm2.

Tuning the Pharmacokinetic Performance of Quercetin by Cocrystallization

Quercetin (QUE) is a widely studied nutraceutical with a number of potential therapeutic properties. Although QUE is abundant in the plant kingdom, its poor solubility (≤20 μg/mL) and poor oral bioavailability have impeded its potential utility and clinical development. In this context, cocrystallization has emerged as a useful method for improving the physicochemical properties of biologically active molecules. We herein report a novel cocrystal of the nutraceutical quercetin (QUE) with the coformer pentoxifylline (PTF) and a solvate of a previously reported structure between QUE and betaine (BET). We also report the outcomes of in vitro and in vivo studies of QUE release and absorption from a panel of QUE cocrystals: betaine (BET), theophylline (THP), l-proline (PRO), and novel QUEPTF. All cocrystals were found to exhibit an improvement in the dissolution rate of QUE. Further, the QUE plasma levels in Sprague-Dawley rats showed a 64-, 27-, 10- and 7-fold increase in oral bioavailability for QUEBET·MeOH, QUEPTF, QUEPRO, and QUETHP, respectively, compared to QUE anhydrate. We rationalize our in vivo and in vitro findings as the result of dissolution-supersaturation-precipitation behavior.

Impact of Silica Dry Coprocessing with API and Blend Mixing Time on Blend Flowability and Drug Content Uniformity

This paper considers two fine-sized (d50 ∼10 µm) model drugs, acetaminophen (mAPAP) and ibuprofen (Ibu), to examine the effect of API dry coprocessing on their multi-component medium DL (30 wt%) blends with fine excipients. The impact of blend mixing time on the bulk properties such as flowability, bulk density, and agglomeration was studied. The hypothesis tested is that blends with fine APIs at medium DL require good blend flowability to have good blend uniformity (BU). Moreover, the good flowability could be achieved through dry coating with hydrophobic (R972P) silica, which reduces agglomeration of not only fine API, but also of its blends while using fine excipients. For uncoated APIs, the blend flowability was poor, i.e. cohesive regime at all mixing times, and the blends failed to achieve acceptable BU. In contrast, for dry coated APIs, their blend flowability improved to easy-flow regime or better, improving with mixing time, and as hypothesized, all blends consequently achieved desired BU. All dry coated API blends exhibited improved bulk density and reduced agglomeration, attributed to mixing induced synergistic property enhancements, likely due to silica transfer. Despite coating with hydrophobic silica, tablet dissolution was improved, attributed to the reduced agglomeration of fine API.

Innovative multiple nanoemulsion (W/O/W) based on Chilean honeybee pollen improves their permeability, antioxidant and antibacterial activity

Beehive derivatives, including honeybee pollen (HBP), have been extensively studied for their beneficial health properties and potential therapeutic use. Its high polyphenol content gives it excellent antioxidant and antibacterial properties. Today its use is limited due to poor organoleptic properties, low solubility, stability, and permeability under physiological conditions. A novel edible multiple W/O/W nanoemulsion (BP-MNE) to encapsulate the HBP extract was designed and optimized to overcome these limitations. The new BP-MNE has a small size (∼100 nm), a zeta potential greater than +30 mV, and efficiently encapsulated phenolic compounds (∼82%). BP-MNE stability was measured under simulated physiological conditions and storage conditions (4 months); in both cases, stability was promoted. The formulation's antioxidant and antibacterial (Streptococcus pyogenes) activity was analyzed, obtaining a higher effect than the non-encapsulated compounds in both cases. In vitro permeability was tested, observing a high permeability of the phenolic compounds when they are nanoencapsulated. With these results, we propose our BP-MNE as an innovative solution to encapsulate complex matrices, such as HBP extract, as a platform to develop functional foods.

Characterization of sulfasalazine-bovine serum albumin and human serum albumin interaction by spectroscopic and theoretical approach

The interaction of sulfasalazine (SZ) with the carrier proteins bovine serum albumin (BSA) and human serum albumin (HSA) was explored by fluorescence, absorption and circular dichroism (CD) spectroscopy along within silicotechniques. The spectral alteration observed in fluorescence, absorption and CD spectra upon the addition of SZ confirmed the complex formation of SZ with BSA and HSA. The inverse temperature dependence behaviour of theK_svvalues as well as the increase in the protein's absorption signals after the addition of SZ indicate that SZ triggered quenching of BSA/HSA fluorescence as the static quenching. The binding affinity (k_b) of the order of 10⁶ M^-1 was reported towards the BSA-SZ and HSA-SZ association process. Interpretation of thermodynamic data (enthalpy change = -93.85 kJ mol^-1and entropy change = -200.81 J mol^-1K^-1for BSA-SZ system; enthalpy change = -74.12 kJ mol^-1and entropy change = -123.90 J mol^-1K^-1for HSA-SZ system) anticipated that hydrogen bond and van der Waals forces were the main intermolecular forces in the complex stabilization. Inclusion of SZ to BSA/HSA produced microenvironmental perturbations around Tyr and Trp residues. The UV, synchronous and 3D analysis confirmed the structural alteration of proteins after SZ binding, which was supported by CD results. The binding location of SZ in BSA/HSA was detected in Sudlow's site I (subdomain IIA) and the same was revealed by competitive site-marker displacement investigations. Density functional theory study was done to comprehend the feasibility of the analysis and to optimize the structure and energy gap that validated the experimental results. This study is expected to provide deep information about the pharmacology of SZ with its pharmacokinetic properties.

Are pediatrics taking the prescribed tablet dosage form? Practices of off-label tablet modification in pediatric wards: A prospective observational study

Tablet manipulation (modification) is a practice where the licensed tablet product is customized into reduced fractions of doses or changed into dispersions using solvents because of suitable dose for paediatrics and neonates are frequently unavailable. As a result, unlicensed dosage form frequently used after manipulation, outside what is approved by drug regulatory authorities.

Objective

To assess the practice of off-label tablet manipulation in pediatric and neonatal wards at selected public hospitals in Ethiopia.

Methods

A prospective, direct observational approach was used to investigate the frequency, nature and appropriateness of tablet manipulations in neonatal and pediatrics patients of two public hospitals of Ethiopia from April 12, to June 30, 2021.

Results

During the study period a total of 303 tablet manipulations were observed. Two hundred nine (69%) of tablets were dispensed to pediatric patients to be taken after split into lower strengths. The remaining nighty four (31%) tablets were manipulated into dispersion using 0.9% normal saline as a main solvent. Interestingly, 48 (15.8%) of tablet manipulations into dispersions involved practically insoluble drugs whose manipulation may probably affect their bioavailability. In 12.5% (12/94) dispersion manipulations, large undissolved fractions were observed during administration through naso-gastric tubes. The most commonly manipulated tablets were drugs for central nervous system (n = 135, 44.6%) followed by cardiovascular drugs (n = 85, 28%).

Conclusions

and recommendations: The study revealed the off-label use of tablets for pediatrics age groups is very common in Ethiopia. Evidence-based guidelines for tablet manipulations should be practiced to improve the safety of paediatric drug use. As for policy implication, this study concurs with previous scientific recommendations that manufacturers introduce a wide range of dosage forms to reduce the need for manipulations.

Crushing lopinavir/ritonavir tablets does not result in lower exposure to lopinavir/ritonavir in adult patients with COVID-19

OBJECTIVE

Lopinavir/ritonavir (LPV/RTV) exposure is decreased in children after crushing the tablets. Whether exposure is also decreased in adult patients is not known. This study evaluated the exposure of LPV/RTV in adult patients after administration of crushed LPV/RTV tablets.

METHODS

Blood samples were drawn from patients with COVID-19 who were receiving crushed LPV/RTV 400/100 mg tablets twice daily.

RESULTS

Plasma concentrations for 11 patients with COVID-19 (eight men, mean age 62.6 years) were included. The measured plasma concentrations of LPV were substantially higher than reported for patients with HIV.

CONCLUSIONS

There is adequate exposure from crushed LPV/RTV tablets, but because of limited experience, therapeutic drug monitoring is still advised.

Selected Aspects of the Analytical and Pharmaceutical Profiles of Nifurtimox

Nifurtimox is a nitroheterocyclic drug employed for treatment of trypanosomiases (Chagas disease and West African sleeping sickness); its use for certain cancers has also been assessed. Despite having been in the market for over 50 years, knowledge of nifurtimox is still fragmentary and incomplete. Relevant aspects of the chemistry and biology of nifurtimox are reviewed to summarize the current knowledge of this drug. These comprise its chemical synthesis and the preparation of some analogues, as well as its chemical degradation. Selected physical data and physicochemical properties are also listed, along with different approaches toward the analytical characterization of the drug, including electrochemical (polarography, cyclic voltammetry), spectroscopic (ultraviolet-visible, nuclear magnetic resonance, electron spin resonance), and single crystal X-ray diffractometry. The array of polarographic, ultraviolet-visible spectroscopic, and chromatographic methods available for the analytical determination of nifurtimox (in bulk drug, pharmaceutical formulations, and biological samples), are also presented and discussed, along with chiral chromatographic and electrophoretic alternatives for the separation of the enantiomers of the drug. Aspects of the drug likeliness of nifurtimox, its classification in the Biopharmaceutical Classification System, and available pharmaceutical formulations are detailed, whereas pharmacological, chemical, and biological aspects of its metabolism and disposition are discussed.

Fabrication of betamethasone micro- and nanoparticles using supercritical antisolvent technology: In vitro drug release study and Caco-2 cell cytotoxicity evaluation

Poor solubility limits the pharmacological activities of betamethasone (BM), including its anti-inflammatory and anti-allergic effects. To improve the aqueous solubility and dissolution rate of BM, supercritical antisolvent (SAS) technology was used to prepare BM microparticles and BM-polyvinylpyrrolidone (PVP) solid dispersion nanoparticles. The effects of temperature, pressure, solution feeding rate, and drug concentration on particle formation were investigated using both single-factor and orthogonal experimental methods, and the optimal preparation process was screened. The physicochemical properties of the BM particles were characterized by scanning electron microscopy, differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction. After the SAS process, the particle size was reduced significantly and the crystalline shape was altered, which considerably increased the solubility and dissolution rate of BM. Furthermore, the toxicity of BM to live cells was reduced because of the BM-PVP solid dispersions.

Nanoparticle-based chewable gels of praziquantel

Chewable gels present significant advantages over conventional dosage forms, despite their development is not comprehensively assessed. In this sense, six formulations, varying gelatine concentration, dose, and form of incorporation of praziquantel, were developed and characterized. The novelty of this approach focused not only on the development of the formulation itself but also on the incorporation of the drug in a nanoparticulated form. The obtained results for moisture content, water activity, pH, and drug content were within the expected values for this type of formulation. On the other hand, texture and disintegration parameters were influenced by the form of incorporation of praziquantel and the amount of gelatine added. Finally, in vitro dissolution of chewable gels showed significant differences with intermediate products, though the improved dissolution of the nanoparticulated drug was maintained. In conclusion, nanoparticulate drugs can be incorporated into these semisolid formulations and could be successfully applied to other low-aqueous solubility drugs.

Potential application of nanotechnology in the treatment, diagnosis, and prevention of schistosomiasis

Schistosomiasis is one of the neglected tropical diseases that affect millions of people worldwide. Globally, it affects economically poor countries, typically due to a lack of proper sanitation systems, and poor hygiene conditions. Currently, no vaccine is available against schistosomiasis, and the preferred treatment is chemotherapy with the use of praziquantel. It is a common anti-schistosomal drug used against all known species of Schistosoma. To date, current treatment primarily the drug praziquantel has not been effective in treating Schistosoma species in their early stages. The drug of choice offers low bioavailability, water solubility, and fast metabolism. Globally drug resistance has been documented due to overuse of praziquantel, Parasite mutations, poor treatment compliance, co-infection with other strains of parasites, and overall parasitic load. The existing diagnostic methods have very little acceptability and are not readily applied for quick diagnosis. This review aims to summarize the use of nanotechnology in the treatment, diagnosis, and prevention. It also explored safe and effective substitute approaches against parasitosis. At this stage, various nanomaterials are being used in drug delivery systems, diagnostic kits, and vaccine production. Nanotechnology is one of the modern and innovative methods to treat and diagnose several human diseases, particularly those caused by parasite infections. Herein we highlight the current advancement and application of nanotechnological approaches regarding the treatment, diagnosis, and prevention of schistosomiasis.

Antifungal Activity of Camelus-Derived LFA-LFC Chimeric Peptide Gelatin Film and Effect on Oral Bacterial Biofilm

The objective of this study was to construct lactoferrin (LFA-LFC) chimeric peptide gelatin drug-loaded fiber film by tissue engineering strategy, and study its bacteriostatic effect on oral pathogens (especially Candida albicans) and its effect on biofilm. First of all, LFA-LFC chitosan nanoparticles were prepared firstly, and then fluconazole gelatin (LF/GH/F) film loaded with LFA-LFC was prepared by electrospinning. Scanning electron microscope (SEM), mechanical strength, drug release, cytotoxicity, and real-time PCR were used to test the properties of the synthesized materials. SEM showed that there was the reticular structure for fiber film before and after cross-linking. LF/GH/F film had no obvious cytotoxicity, with good biocompatibility and drug release; real-time PCR and antibacterial test showed that the LF/GH/F film had good antibacterial activity. LF/GH/F film has a good inhibitory effect on oral pathogens, and its mechanism is related to biofilm. The antibacterial experiments of nanofiber membrane in vitro and the effect of bacterial biofilm were carried out. The effect of LF/GH/F on oral microbial flora structure was studied by fluorescence quantitative pest techniques.

Influence of permeability enhancers on the paracellular permeability of metformin hydrochloride and furosemide across Caco-2 cells

Permeability enhancers can affect absorption of paracellularly transported drugs. This study aims to evaluate effects of permeability enhancers (chitosan, methyl-β -cyclodextrin, sodium caprate, sodium lauryl sulfate, etc.) on the permeability of paracellularly absorbed furosemide and metformin hydrochloride. Methyl thiazole tetrazolium bromide test was carried out to determine the drug concentrations in permeability study. Trans-epithelial electrical resistance (TEER) values determined to assess the integrity of tight junctions. Permeability enhancers were applied at different concentrations alone, in dual/triple combinations. Permeability was determined using human colorectal adenocarcinoma (Caco-2) cells (TEER > 400 Ω·cm²). Permeability enhancers have no significant effect (<2-fold; p > 0.05) on the permeability of furosemide (1.80 × 10^-5 ± 4.55 × 10^-7 cm/s); however, metformin permeability (1.36 × 10^-5 ± 1.25 × 10^-6 cm/s) increased significantly (p < 0.05) with 0.3% and 0.5% (w/v) chitosan (2.0- and 2.7-fold, respectively), 1% methyl-β -cyclodextrin (w/v) (3.5-fold), 10 and 20 µmol/L sodium caprate (2.2- and 2.8-fold, respectively), and 0.012% sodium lauryl sulfate (w/v) (1.9-fold). Furosemide permeability increased significantly (p < 0.05) with chitosan-sodium lauryl sulfate combination (1.7-fold), and all triple combinations (1.4- to 1.9-fold). Chitosan containing dual/triple combinations resulted in significant increase (p < 0.05) in metformin permeability (1.7 to 2.8-fold). All results indicated that absorption of furosemide and metformin can be improved by the combination of permeability enhancers. Therefore, it can be evaluated for the formulation of development strategies containing furosemide and metformin by the pharmaceutical industry.

Kinetics of Drug Release from Clay Using Enhanced Sampling Methods

A key step in the development of a new drug, is the design of drug-excipient complexes that lead to optimal drug release kinetics. Computational chemistry and specifically enhanced sampling molecular dynamics methods can play a key role in this context, by minimizing the need for expensive experiments, and reducing cost and time. Here we show that recent advances in enhanced sampling methodologies can be brought to fruition in this area. We demonstrate the potential of these methodologies by simulating the drug release kinetics of the complex praziquantel-montmorillonite in water. Praziquantel finds promising applications in the treatment of schistosomiasis, but its biopharmaceutical profile needs to be improved, and a cheap material such as the montmorillonite clay would be a very convenient excipient. We simulate the drug release both from surface and interlayer space, and find that the diffusion of the praziquantel inside the interlayer space is the process that limits the rate of drug release.

Drug Physicochemical Properties and Capsule Fill Determine Extent of Premature Gastric Release from Enteric Capsules

Intrinsically, enteric capsule shells offer several advantages compared to coating of dosage forms with enteric polymers. We undertook a systematic investigation to elucidate capsule-fill parameters that may result in premature gastric drug release from Vcaps^® Enteric capsules (Lonza CHI, Morristown, NJ, USA). Four model drugs with different ionization and solubility profiles were investigated: acetaminophen, ketoprofen, trimethoprim and atenolol. Different fill loads, diluents and drug-to-diluent ratios were explored. Enteric capsules were filled with drug or drug and diluent powder mix and underwent USP II dissolution testing using mini-vessels and paddles. Capsules were tested in pH 2 (0.01 M HCl) or pH 4.5 (3.2 × 10^-5 M HCl) 200 mL acid media to simulate normal, fasted or hypochlorhydric gastric pH, respectively. Acetaminophen, trimethoprim and atenolol displayed premature gastric drug release from enteric capsules. The extent of premature release was dependent on drug solubility, ionization profile and capsule-fill level. At 100 mg drug-fill level, acetaminophen, trimethoprim and atenolol gave rise to 10.6, 12.2 and 83.1% drug release, respectively, in normal, fasted, gastric fluids. Diffusion layer pH of trimethoprim and atenolol in pH 2 media was determined to be pH 6.3 and 10.3, respectively. Upon increasing capsule-fill load using microcrystalline cellulose as a diluent, a significant reduction in premature gastric release was observed. However, including mannitol as a diluent was only effective at decreasing premature drug release at a low drug-to-diluent ratio. Systematic in vitro screening of enteric capsule fills needs to be conducted to ensure that drug product performance is not compromised.

Human targeted phenobarbital presents a poor substrate of gut microbiome deciphering new drug targets beyond pharmacokinetic curbs

Background

The gut microbiome, a new organ of the body, can potentially alter the pharmacokinetics of orally administered drugs through microbial enzymes. However, absorption of orally administered non-antibiotic drugs by the gut microbiome, during drug-microbiome interaction, is barely addressed. Structural homology studies confirm similar membrane transport proteins in gut epithelial cells and the gut microbiome of the host that may compete for drug substrates with the host itself for its absorbance. Therefore, it is hypothesized that orally administered human targeted phenobarbital may interact and/or be uptake by the gut microbiome during its transit through the small intestine.

Methods

In the current in vivo study, thirty-six male Wistar albino rats were divided into six groups including one control and 5 treatment groups, each having an equal number of rats (n = 6). Phenobarbital was administered orally (single dose of 15 mg/kg bw) to treatment groups. Animals were subsequently sacrificed to harvest microbial mass pallets residing in the small intestine after 2, 3, 4, 5, and 6 h of phenobarbital administration. Phenobarbital absorbance by the microbiome in the microbial lysate was estimated through RP-HPLC–UV at a wavelength of 207 nm.

Results

Maximum phenobarbital absorbance (149.0 ± 5.93 µg) and drug absorbance per milligram of microbial mass (1.19 ± 0.05 µg) were found significantly higher at 4 h of post-administration in comparison to other groups. Percent dose recovery of phenobarbital was 5.73 ± 0.19% at 4 h while the maximum intestinal transit time was 5 h till the drug was absorbed by the microbes. Such results pronounce the idea of the existence of structural homology between membrane transporters of the gut microbiome and intestinal enterocytes of the host that may competitively absorb orally administered phenobarbital during transit in the small intestine. The docking studies revealed that the phenobarbital is a poor substrate for the gut microbiome.

Conclusion

Gut microbiome may competitively absorb the non-antibiotics such as phenobarbital as novel substrates due to the presence of structurally homologous transporting proteins as in enterocytes. This phenomenon suggests the microbiome as a potential candidate that can significantly alter the pharmacokinetics of drugs.

Development of a safe pediatric liquisolid self-nanoemulsifying system of triclabendazole for the treatment of fascioliasis

Fascioliasis, a common parasitic infection observed in the pediatric patient population, is a leading cause of concern in countries with poor/unhealthy water resources. To treat this condition first line agent such as triclabendazole (TBZ) has been the choice therapy. However, there is a major hurdle in exploiting TBZ. Characterized with poor aqueous solubility (0.1 mg/L), its solubility has been the rate limiting factor, rendering requirement of large doses of TBZ. To address the same, the focus of the current study was to develop a self-nano emulsifying drug delivery system (TBZ-SNEDDS) for TBZ and developing dose customizable pediatric dispersible color-coded tablets. TBZ-SNEDDS were successfully formulated by using Kolliphor®EL, as a surfactant, a lipid phase of medium chain triglyceride and α-tocopherol in the ratio of (1:1), with dimethylacetamide (DMA) as a solvent. It was observed during in vitro release studies that there was a significant effect of fed conditions on the rate of TBZ release from the formulation. greater than 85 % TBZ was observed to release in fed conditions in comparison to fasted conditions. As currently TBZ is prescribed on a weight-based dosage regimen, it is imperative to develop a dose-customizable fast dissolving pediatric formulation. Hence, TBZ-SNEDDS could prove to be pivotal in helping countless children around the world in desperate conditions to get cheap yet effective therapy.

Niosomes: a novel targeted drug delivery system for cancer

Recently, nanotechnology is involved in various fields of science, of which medicine is one of the most obvious. The use of nanoparticles in the process of treating and diagnosing diseases has created a novel way of therapeutic strategies with effective mechanisms of action. Also, due to the remarkable progress of personalized medicine, the effort is to reduce the side effects of treatment paths as much as possible and to provide targeted treatments. Therefore, the targeted delivery of drugs is important in different diseases, especially in patients who receive combined drugs, because the delivery of different drug structures requires different systems so that there is no change in the drug and its effectiveness. Niosomes are polymeric nanoparticles that show favorable characteristics in drug delivery. In addition to biocompatibility and high absorption, these nanoparticles also provide the possibility of reducing the drug dosage and targeting the release of drugs, as well as the delivery of both hydrophilic and lipophilic drugs by Niosome vesicles. Since various factors such as components, preparation, and optimization methods are effective in the size and formation of niosomal structures, in this review, the characteristics related to niosome vesicles were first examined and then the in silico tools for designing, prediction, and optimization were explained. Finally, anticancer drugs delivered by niosomes were compared and discussed to be a suitable model for designing therapeutic strategies. In this research, it has been tried to examine all the aspects required for drug delivery engineering using niosomes and finally, by presenting clinical examples of the use of these nanocarriers in cancer, its clinical characteristics were also expressed.

Reliable Prediction of Caco-2 Permeability by Supervised Recursive Machine Learning Approaches

The heterogeneity of the Caco-2 cell line and differences in experimental protocols for permeability assessment using this cell-based method have resulted in the high variability of Caco-2 permeability measurements. These problems have limited the generation of large datasets to develop accurate and applicable regression models. This study presents a QSPR approach developed on the KNIME analytical platform and based on a structurally diverse dataset of over 4900 molecules. Interpretable models were obtained using random forest supervised recursive algorithms for data cleaning and feature selection. The development of a conditional consensus model based on regional and global regression random forest produced models with RMSE values between 0.43–0.51 for all validation sets. The potential applicability of the model as a surrogate for the in vitro Caco-2 assay was demonstrated through blind prediction of 32 drugs recommended by the International Council for the Harmonization of Technical Requirements for Pharmaceuticals (ICH) for validation of in vitro permeability methods. The model was validated for the preliminary estimation of the BCS/BDDCS class. The KNIME workflow developed to automate new drug prediction is freely available. The results suggest that this automated prediction platform is a reliable tool for identifying the most promising compounds with high intestinal permeability during the early stages of drug discovery.

β-Artemether and Lumefantrine Dual Drug Loaded Lipid Nanoparticles: Physicochemical Characterization, Pharmacokinetic Evaluation and Biodistribution Study

BACKGROUND

β-artemether (BAT) and lumefantrine (LFT) combination therapies are well recognized for the treatment of malaria. However, the current conventional formulations have several drawbacks.

OBJECTIVE

The study aims to develop novel lipid nanoparticles (LNP) for efficient delivery of BAT and LFT.

METHODS

The LNP were prepared by solvent injection method and optimized by the Box-Behnken experimental design to achieve the desired particle size, maximum entrapment efficiency (EE), and percentage drug release. BAT and LFT in rat plasma were estimated by liquid chromatographytandem mass spectrometry (LC-MS/MS).

RESULTS

Freeze-dried LNP comprised of 78.74% (w/w) lipid, 15.74% (w/w) surfactant, 3.93% (w/w) co-surfactant and 1.57% mannitol with respect to the total inactive components. Mean particle size and zeta potential were found to be 140.22 ± 1.36 nm and -35.23 mv, respectively. EE was 80.60 ± 3.85% for BAT and 69.64 ± 2.63% for LFT. The optimized formulation exhibited a biphasic release profile in phosphate buffer (pH 7.2). In vivo study revealed an increased bioavailability of BAT and LFT from dual drug loaded LNP compared to the pure drug solution. Moreover, the tissue distribution study confirmed the high uptake of both the drugs in the liver and spleen.

CONCLUSION

The study demonstrated the potential use of the developed formulation for oral administration in the treatment of malaria.

Mini-tablets as technological strategy for modified release of morphine sulfate

The aim of this study was to use intelligent formulation design for development of mini-tablets for modified release of morphine sulfate. A formulation (F1) was proposed using the Hiperstart® software. Based on the suggested formulation, two other formulations (F2 and F3) were prepared: one for modified and another for immediate drug release. The powders were characterized as bulk and tapped density, Hausner's factor and compressibility index analyzes. Mini-tablets were directly compressed and characterized as hardness, friability, size, and weight variation. The in vitro drug release profile was carried out according to the apparatus 1 of USP. Formulations showed good flow properties, and the mini-tablets displayed characteristics according to the specified. In comparison to F3 (immediate release), F1 and F2 displayed slower drug release time, showing the efficiency of the matrix formed. F3 displayed 90% of drug released up to 10 min, while F1 and F2 required 240 min. The results highlight the importance to use intelligent formulation design for the development of improved mini-tablet matrices. Formulation F1 was found to be suitable for modified morphine sulfate release. Further studies with more formulations are necessary for production of optimized mini-tablets with suitable prolonged morphine sulfate release.

Comorbidities and the right dose: antipsychotics

INTRODUCTION

The effects of antipsychotic drugs are dose-dependent, which is particularly true for their efficacy, each antipsychotic having a specific dose-response curve. This may justify individualizing doses for these agents.

AREAS COVERED

We review the pharmacokinetic profiles of seven oral antipsychotics: haloperidol, risperidone, olanzapine, clozapine, quetiapine, ziprasidone, and aripiprazole. Their main indications are psychotic and affective disorders. They are prescribed in a very large population which may have comorbidities. Hence, we analyze the impact of the latter on the pharmacokinetic profiles of these antipsychotics, focusing on renal and hepatic impairment. Reviews and clinical trials were discussed based on a systematic literature search (PubMed) ranging from 1995 to 2022.

EXPERT OPINION

Factors liable to impact antipsychotic dosage are numerous and their subsequent effects often hard to predict, due to multi-level interactions and compensatory phenomena. In clinical practice, physicians must be aware of these potential effects, but base their decisions on monitoring antipsychotic plasma levels.

Solid dispersions based on chitosan/hypromellose phthalate blends to modulate pharmaceutical properties of zidovudine

Zidovudine (AZT) has been widely used alone or in combination with other antiretroviral drugs for the treatment of human immunodeficiency virus. Its erratic oral bioavailability necessitates frequent administration of high doses, resulting in severe side effects. In this study, the design of mucoadhesive solid dispersions (SDs) based on chitosan (CS) and hypromellose phthalate (HP) was rationalized as a potential approach to modulate AZT physicochemical and pharmaceutical properties. SDs were prepared at different drug:polymer ratios, using an eco-friendly technique, which avoids the use of organic solvents. Particles with diameter from 56 to 73 µm and negative zeta potentials (-27 to -32 mV) were successfully prepared, achieving high drug content. Infrared spectroscopy revealed interactions between polymers but no interactions between the polymers and AZT. Calorimetry and X-ray diffraction analyses showed that AZT was amorphized into the SDs. The mucoadhesive properties of SDs were evidenced, and the control of AZT release rates from the matrix was achieved, mainly in acid media. The simple, low-cost and scalable technology proposed for production of SDs as a carrier platform for AZT is an innovative approach, and it proved to be a feasible strategy for modulation the physico-chemical, mucoadhesive and release properties of the drug.

Improving translational power in antischistosomal drug discovery

Schistosomiasis is a poverty-associated tropical disease caused by blood dwelling trematodes that threaten approximately 10% of the world population. Praziquantel, the sole drug currently available for treatment, is insufficient to eliminate the disease and the clinical drug development pipeline is empty. Here, we review the characteristics of the patent Schistosoma mansoni mouse model used for in vivo antischistosomal drug discovery, highlighting differences in the experimental set-up across research groups and their potential influence on experimental results. We explore the pharmacokinetic/pharmacodynamic relationship of selected drug candidates, showcasing opportunities to improve the drug profile to accelerate the transition from the early drug discovery phase to new clinical candidates.

Cyclodextrin Complexation of Fenofibrate by Co-Grinding Method and Monitoring the Process Using Complementary Analytical Tools

Solvent-free preparation types for cyclodextrin complexation, such as co-grinding, are technologies desired by the industry. However, in-depth analytical evaluation of the process and detailed characterization of intermediate states of the complexes are still lacking in areas. In our work, we aimed to apply the co-grinding technology and characterize the process. Fenofibrate was used as a model drug and dimethyl-β-cyclodextrin as a complexation excipient. The physical mixture of the two substances was ground for 60 min; meanwhile, samples were taken. A solvent product of the same composition was also prepared. The intermediate samples and the final products were characterized with instrumental analytical tools. The XRPD measurements showed a decrease in the crystallinity of the drug and the DSC results showed the appearance of a new crystal form. Correlation analysis of FTIR spectra suggests a three-step complexation process. In vitro dissolution studies were performed to compare the dissolution properties of the pure drug to the products. Using a solvent-free production method, we succeeded in producing a two-component system with superior solubility properties compared to both the active ingredient and the product prepared by the solvent method. The intermolecular description of complexation was achieved with a detailed analysis of FTIR spectra.

Study on Hydration and Dehydration of Ezetimibe by Terahertz Spectroscopy with Humidity-Controlled Measurements and Theoretical Analysis

Understanding the solid-state transitions of active pharmaceutical ingredients (APIs) is essential for quality control since differences in their forms affect the bioavailability of APIs. Terahertz (THz) frequency-domain spectroscopy is suitable for such an application since it can sensitively probe the lattice phonon modes originating in the crystal structures. THz absorption spectra were obtained for ezetimibe (EZT) and ezetimibe monohydrate (EZT-MH), which have similar crystalline structures and belong to the same space group. The observed absorption spectrum of EZT matched well with the solid-state density functional theory (ss-DFT)-simulated spectrum for the structures at 0 K and room temperature (modeled using constrained unit cell volumes). However for EZT-MH, the ss-DFT spectrum of the room-temperature structure showed better correlation with the experimental THz spectrum than that of the simulated spectrum of the 0 K structures, suggesting that the EZT-MH crystal has greater anharmonic character. Gibbs free-energy curves were calculated, and EZT-MH was found to be more stable than pure EZT and water in a broad temperature range. The hydrate stability may be influenced by the existence of more hydrogen bonds in EZT-MH. The hydration and dehydration of EZT in a pure API tablet and formulation tablets were monitored using a THz spectrometer with a humidity-controlled sample chamber. The effect of the excipient in the formulation tablet on hydration was successfully confirmed by showing that the solid-state transition of the API with excipients is significantly slower than that without it. Under a relative humidity of 60%, hydration of EZT in a pure EZT tablet occurred in 200 min, while the hydration of EZT in a formulation tablet was 50 times slower.

Use of Flory-Huggins Interaction Parameter and Contact Angle Values to Predict the Suitability of the Drug-Polymer System for the Production and Stability of Nanosuspensions

PURPOSE

Use of Flory-Huggins interaction parameter and contact angle values to predict the suitability of the drug-polymer system for the production and stability of nanosuspensions.

MATERIAL AND METHODS

Melting point depression of the drug was measured using differential scanning calorimetry. Interaction parameter, χ, was calculated using the melting point depression data to elucidate the drug-polymer interaction strength to predict the suitability of the drug-polymer system for the production and stability of nanosuspensions. Contact angle of the drug films were measured with purified water and 0.1%w/w polymer solutions to predict polymer's suitability for the production and stability of nanosuspension. Nanosuspensions were manufactured to validate the application of the melting point depression approach along with surface property information.

RESULTS

All three polymers, HPMC, Soluplus®, and poloxamer exhibited a negative interaction parameter with naproxen and budesonide. Higher negative interaction parameter values for the naproxen-polymer system indicated stronger drug-polymer interactions, while smaller negative interaction parameter values for the budesonide-polymer system indicated weaker drug-polymer interactions. Interaction parameter was not obtained for fenofibrate with HPMC and Soluplus®, and similarly, no interaction parameter was obtained for carvedilol with HPMC, most likely due to weaker drug-polymer interactions. All three polymers provided lower equilibrium contact angle values when compared to purified water, indicating an affinity for polymers.

CONCLUSIONS

Successful production and stability of several nanosuspensions were correlated with Flory-Huggins's interaction parameter and contact angle values. In the absence of melting point depression, contact angle values can also be used predict the agglomeration tendencies as we have shown for this study.