Long-Term Constant Subcutaneous Drug Administration

In this chapter, a long-term drug delivery system for preclinical therapeutic research is introduced. By using a subcutaneously implanted ALZET® Osmotic Pumps osmotic pump, continuous zero-order delivery of drugs under investigation that need repeated oral or intravenous dosing is realizable. Compared to traditional delivery systems, implanted osmotic pumps present several advantages, such as that no external connections or researcher intervention is required during infusion and that it is possible to save time by eliminating the need for frequent animal handling and repetitive injection schedules. Most importantly, a stable peripheral concentration of a drug can be obtained using this constant drug delivery system, which would benefit researchers in verifying the efficiency of anti-rheumatoid drugs and establishing safety profiles in preclinical studies.

Topical delivery of seriniquinone for treatment of skin cancer and fungal infections is enabled by a liquid crystalline lamellar phase

Seriniquinone (SQ) was initially described by our group as an antimelanoma drug candidate and now also as an antifungal drug candidate. Despite its promising in vitro effects, SQ translation has been hindered by poor water-solubility. In this paper, we described the challenging nanoformulation process of SQ, which culminated in the selection of a phosphatidylcholine-based lamellar phase (PLP1). Liposomes and nanostructured lipid carriers were also evaluated but failed to encapsulate the compound. SQ-loaded PLP1 (PLP1-SQ) was characterized for the presence of sedimented or non-dissolved SQ, rheological and thermal behavior, and irritation potential with hen's egg test on the chorioallantoic membrane (HET-CAM). PLP1 influence on transepidermal water loss (TEWL) and skin penetration of SQ was assessed in a porcine ear skin model, while biological activity was evaluated against melanoma cell lines (SK-MEL-28 and SK-MEL-147) and C. albicans SC5314. Despite the presence of few particles of non-dissolved SQ (observed under the microscope 2 days after formulation obtainment), PLP1 tripled SQ retention in viable skin layers compared to SQ solution at 12 h. This effect did not seem to relate to formulation-induced changes on the barrier function, as no increases in TEWL were observed. No sign of vascular toxicity in the HET-CAM model was observed after cutaneous treatment with PLP1. SQ activity was maintained on melanoma cells after 48 h-treatment (IC50 values of 0.59-0.98 µM) whereas the minimum inhibitory concentration (MIC) against C. albicans after 24 h-treatment was 32-fold higher. These results suggest that a safe formulation for SQ topical administration was developed, enabling further in vivo studies.

Advancing algorithmic drug product development: Recommendations for machine learning approaches in drug formulation

Artificial intelligence is a rapidly expanding area of research, with the disruptive potential to transform traditional approaches in the pharmaceutical industry, from drug discovery and development to clinical practice. Machine learning, a subfield of artificial intelligence, has fundamentally transformed in silico modelling and has the capacity to streamline clinical translation. This paper reviews data-driven modelling methodologies with a focus on drug formulation development. Despite recent advances, there is limited modelling guidance specific to drug product development and a trend towards suboptimal modelling practices, resulting in models that may not give reliable predictions in practice. There is an overwhelming focus on benchtop experimental outcomes obtained for a specific modelling aim, leaving the capabilities of data scraping or the use of combined modelling approaches yet to be fully explored. Moreover, the preference for high accuracy can lead to a reliance on black box methods over interpretable models. This further limits the widespread adoption of machine learning as black boxes yield models that cannot be easily understood for the purposes of enhancing product performance. In this review, recommendations for conducting machine learning research for drug product development to ensure trustworthiness, transparency, and reliability of the models produced are presented. Finally, possible future directions on how research in this area might develop are discussed to aim for models that provide useful and robust guidance to formulators.

Self-assembly of CXCR4 antagonist peptide-docetaxel conjugates for breast tumor multi-organ metastasis inhibition

As a representative chemotherapeutic drug, docetaxel (DTX) has been used for breast cancer treatment for decades. However, the poor solubility of DTX limits its efficacy, and the DTX based therapy increases the metastasis risk due to the upregulation of C-X-C chemokine receptor type 4 (CXCR4) expression during the treatment. Herein, we conjugated CXCR4 antagonist peptide (CTCE) with DTX (termed CTCE-DTX) as an anti-metastasis agent to treat breast cancer. CTCE-DTX could self-assemble to nanoparticles, targeting CXCR4-upregulated metastatic tumor cells and enhancing the DTX efficacy. Thus, the CTCE-DTX NPs achieved promising efficacy on inhibiting both bone-specific metastasis and lung metastasis of triple-negative breast cancer. Our work provided a rational strategy on designing peptide-drug conjugates with synergistic anti-tumor efficacy.

Strategies for overcoming protein and peptide instability in biodegradable drug delivery systems

The global pharmaceutical market has recently shifted its focus from small molecule drugs to peptide, protein, and nucleic acid drugs, which now comprise a majority of the top-selling pharmaceutical products on the market. Although these biologics often offer improved drug specificity, new mechanisms of action, and/or enhanced efficacy, they also present new challenges, including an increased potential for degradation and a need for frequent administration via more invasive administration routes, which can limit patient access, patient adherence, and ultimately the clinical impact of these drugs. Controlled-release systems have the potential to mitigate these challenges by offering superior control over in vivo drug levels, localizing these drugs to tissues of interest (e.g., tumors), and reducing administration frequency. Unfortunately, adapting controlled-release devices to release biologics has proven difficult due to the poor stability of biologics. In this review, we summarize the current state of controlled-release peptides and proteins, discuss existing techniques used to stabilize these drugs through encapsulation, storage, and in vivo release, and provide perspective on the most promising opportunities for the clinical translation of controlled-release peptides and proteins.

Targeting the gut microbiome to control drug pharmacomicrobiomics: the next frontier in oral drug delivery

INTRODUCTION

The trillions of microorganisms that comprise the gut microbiome form dynamic bidirectional interactions with orally administered drugs and host health. These relationships can alter all aspects of drug pharmacokinetics and pharmacodynamics (PK/PD); thus, there is a desire to control these interactions to maximize therapeutic efficacy. Attempts to modulate drug-gut microbiome interactions have spurred advancements within the field of 'pharmacomicrobiomics' and are poised to become the next frontier of oral drug delivery.

AREAS COVERED

This review details the bidirectional interactions that exist between oral drugs and the gut microbiome, with clinically relevant case examples outlining a clear motive for controlling pharmacomicrobiomic interactions. Specific focus is attributed to novel and advanced strategies that have demonstrated success in mediating drug-gut microbiome interactions.

EXPERT OPINION

Co-administration of gut-active supplements (e.g. pro- and pre-biotics), innovative drug delivery vehicles, and strategic polypharmacy serve as the most promising and clinically viable approaches for controlling pharmacomicrobiomic interactions. Targeting the gut microbiome through these strategies presents new opportunities for improving therapeutic efficacy by precisely mediating PK/PD, while mitigating metabolic disturbances caused by drug-induced gut dysbiosis. However, successfully translating preclinical potential into clinical outcomes relies on overcoming key challenges related to interindividual variability in microbiome composition and study design parameters.

Dimethyl sulfoxide favors the emetic efficacy of lycorine in beagle dogs - a novel strategy for the treatment of poisoning

Poisoning in small animals represents an ongoing hazard and therapeutic problem in veterinary medicine. Therapeutic induction of emesis in time enables a fast elimination of a toxic compound resulting in a shortened course of poisoning and a higher safety level thereafter, which decisively improves prognosis and treatment. Lycorine is a reliable emetic drug in beagle dogs without serious side effects thought to be more beneficial in tolerability and efficacy than the rarely used apomorphine. Therefore, this study investigates efficacy and tolerability of differently composed potential drug formulations of lycorine hydrochloride for s.c. administration in dogs as an emetic principle. By emesis response analysis four dimethyl sulfoxide (DMSO)-based active pharmaceutical ingredient (API) formulations were favored. Two of them (F5 and F6) qualified for further drug development. Both formulations ensure a safe pharmacologically induced emesis within about 30 min after injection, suitable for use as an in time decontaminant in acute poisoning of dogs. DMSO-based formulations were well tolerated and offer a novel promising strategy for treatment of poisoning.

Straightforward adsorption-based formulation of mesoporous silia nanoparticles for drug delivery applications

Mesoporous silica nanoparticles (MSNs) have emerged as a very promising drug delivery platform. However, multi-step synthesis and surface functionalization protocols rise the hurdle for translation of this promising drug delivery platform to the clinic. Furthermore, surface functionalization aiming at enhancing the blood circulation time, typically through surface functionalization with poly(ethylene glycol) (PEG) (PEGylation), has repeatedly been shown to be detrimental for the drug loading levels that can be achieved. Here, we present results related to sequential adsorptive drug loading and adsorptive PEGylation, where the conditions can be chosen so that the drug desorption during PEGylation is minimized. At the heart of the approach is the high solubility of PEG both in water and in apolar solvents, which makes it possible to use a solvent for PEGylation in which the drug exhibits a low solubility, as demonstrated here for two model drugs, one being water soluble and the other not. Analysis of the influence of PEGylation on the extent of serum protein adsorption underline the promise of the approach, and the results also allow the adsorption mechanisms to be elaborated. Detailed analysis of the adsorption isotherms enables determination of the fractions of PEG residing on the outer particle surfaces in comparison to inside the mesopore systems, and also makes it possible to determine the PEG conformation on the outer particle surfaces. Both parameters are directly reflected in the extent of protein adsorption to the particles. Finally, the PEG coating is shown to be stable on time-scales compatible with intravenous drug administration, which is why we are convinced that the presented approach or modifications thereof will pave the way for faster translation of this drug delivery platform to the clinic.

Applications of AFM-IR for drug delivery vector characterization: infrared, thermal, and mechanical characterization at the nanoscale

The development of effective drug delivery systems requires in-depth characterization of the micro- or nanostructure of the material vectors with high spatial resolution, resulting in a deep understanding of the design-function relationship and maximum therapeutic efficacy. Atomic force microscopy-infrared spectroscopy (AFM-IR) combines the high spatial resolution of AFM and the capabilities of IR spectroscopy to identify chemical composition and it has emerged as a powerful tool for the detailed characterization of a drug delivery system at the nanoscale. In addition, the instruments also allow thermal and mechanical evaluation at the nanoscale. In this review, we highlight the applications of AFM-IR in various drug delivery systems, including polymer-based carriers, lipid-contained nanocarriers, and metal-based nanocarriers. The existing challenges as well as the future perspectives for the application of AFM-IR for drug delivery vector characterization are also discussed.

Trends in development and quality assessment of pharmaceutical formulations - F2α analogues in the glaucoma treatment

The ocular delivery route presents a number of challenges in terms of drug administration and bioavailability. The low bioavailability following topical ophthalmic administration shows that there is a clear need for in-depth research aimed at finding both more efficacious molecules and formulations precisely targeted at the site of action. Continuous technological development will eventually result in improved bioavailability, lower dosages, reduced toxicity, fewer adverse effects, and thus better patient compliance and treatment efficacy. Technological development, as well as increasingly stringent quality requirements, help stimulate analytical progress. This is also clearly evident in the case of medicinal products used in the treatment of glaucoma, which are the subject of this review. Impurity profiling of PGF2α analogues, either in the pure substance or in the finished formulation, is a crucial step in assessing their quality. The development of specific, accurate and precise stability-indicating analytical methods for determining the content and related substances seems to be an important issue in relation to this tasks. A total of 27 official and in-house analytical methods are presented that are used for the analysis of latanoprost, travoprost and bimatoprost. The conditions for chromatographic separation with UV or MS/MS detection and the available results obtained during method validation are described. In addition, several aspects are discussed, with particular emphasis on the instability of the analogues in aqueous solution and the phenomenon of isomerism, which affects a potentially large number of degradation products.

Recombinant protein polymers as carriers of chemotherapeutic agents

Chemotherapy is the standard of care for the treatment of cancer and infectious diseases. However, its use is associated with severe toxicity and resistance arising mainly due to non-specificity, resulting in disease progression. The advancement in recombinant technology has led to the synthesis of genetically engineered protein polymers like Elastin-like polypeptide (ELP), Silk-like polypeptide (SLP), hybrid protein polymers with specific sequences to impart precisely controlled properties and to target proteins that have provided satisfactory preclinical outcomes. Such protein polymers have been exploited for the formulation and delivery of chemotherapeutics for biomedical applications. The use of such polymers has not only solved the limitation of conventional chemotherapy but has also improved the therapeutic index of typical drug delivery systems. This review, therefore, summarizes the development of such advanced recombinant protein polymers designed to deliver chemotherapeutics and also discusses the key challenges associated with their current usage and their application in the future.

Preparation and sterilization of an implantable drug-delivery microdevice for clinical use

Implantable drug-delivery microdevices are a key diagnostic and therapeutic tool in medicine with increasing applications. Preparation of such combination drug-delivery devices for human studies requires the development of methods to ensure sterility, safety and integrity on both the device and drug side. Despite growing applications for these technologies, there has been a lack of clear methodology regarding sterilization and preparation to meet strict guidelines set forth by the Food and Drug Administration (FDA). Our laboratory developed a set of widely applicable and straightforward procedures to prepare drug-device combination products for clinical use that consistently achieve the high-quality standards provided by the FDA. This includes several newly developed methods for preparation of the implant including endotoxin removal, appropriate sterilization of raw materials, formulation of novel pharmaceutical agents, and loading of agents into drug delivery reservoirs. We also discuss protocols and methods developed with FDA to meet regulatory guidelines to ensure continual sterility and endotoxin testing, as well as longer-term stability testing of drugs and biologic agents.•

Endotoxin removal and sterilization of raw materials for clinical use.

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Formulation and device loading of novel pharmaceutical agents.

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Continued testing of pharmaceutical agents and devices to meet regulatory guidelines.

From the pharmaceutical to the clinical: the case for effervescent paracetamol in pain management. A narrative review

OBJECTIVE

Paracetamol has an established place in the management of mild-to-moderate pain, but has certain limitations, including varying bioavailability, and potential hepatotoxicity if taken in overdose. Effervescent formulations may help to overcome these limitations.

METHODS

Pubmed searches, with no limits on date or language, were conducted in February 2020. Further references were identified from the reference lists of retrieved articles, and from the authors' knowledge of the field.

RESULTS

Effervescent formulations contain an organic acid (usually citric acid) and carbonate or bicarbonate salts (usually sodium bicarbonate). Upon contact with water, these react to form carbon dioxide, which facilitates the disintegration of the tablet and dissolution of the active drug. Moreover, sodium bicarbonate dose-dependently increases gastric emptying, which together with rapid dissolution facilitates drug absorption. In pharmacokinetic studies, effervescent formulations result in faster absorption of paracetamol than conventional oral formulations, and this translates into a faster onset of analgesia in clinical trials. Effervescent paracetamol has a favorable safety profile, with good tolerability. Importantly, the sodium content of some preparations does not appear to increase cardiovascular risk under real world conditions. Effervescent formulations may also offer advantages in terms of ease of administration and palatability.

CONCLUSIONS

Effervescent formulations of paracetamol result in faster drug absorption, and hence more rapid analgesia, than oral tablets, and offer a favorable tolerability and safety profile. The use of such formulations may therefore help to promote appropriate use of paracetamol.

Optical cryomicroscopy and differential scanning calorimetry of buffer solutions containing cryoprotectants

In the pharmaceutical industry, cryoprotectants are added to buffer formulations to protect the active pharmaceutical ingredient from freeze- and thaw damage. We investigated the freezing and thawing of aqueous sodium citrate buffer with various cryoprotectants, specifically amino acids (cysteine, histidine, arginine, proline and lysine), disaccharides (trehalose and sucrose), polyhydric alcohols (glycerol and mannitol) and surfactants (polysorbate 20 and polysorbate 80). Hereby, we employed optical cryomicroscopy in combination with differential scanning calorimetry in the temperature range to -80 °C. The effect of cryoprotectants on the morphology of the ice crystals, the glass transition temperature and the initial melting temperature is presented. Some of the cryoprotectants have a significant impact on ice crystal size. Disaccharides restrict ice crystal growth, whereas surfactants and glycerol allow ice crystals to increase in size. Cysteine and mannitol cause dehydration after thawing. Either one or two glass transition temperatures were detected, where arginine, surfactants, glycerol, proline and lysine suppress the second, implying a uniform freeze-concentrated solution. The initial melting temperature of pure buffer solution can be shifted up by adding mannitol, both disaccharides and both surfactants; but down by glycerol, proline and lysine.

Impact of gastrointestinal tract variability on oral drug absorption and pharmacokinetics: An UNGAP review

The absorption of oral drugs is frequently plagued by significant variability with potentially serious therapeutic consequences. The source of variability can be traced back to interindividual variability in physiology, differences in special populations (age- and disease-dependent), drug and formulation properties, or food-drug interactions. Clinical evidence for the impact of some of these factors on drug pharmacokinetic variability is mounting: e.g. gastric pH and emptying time, small intestinal fluid properties, differences in pediatrics and the elderly, and surgical changes in gastrointestinal anatomy. However, the link of colonic factors variability (transit time, fluid composition, microbiome), sex differences (male vs. female) and gut-related diseases (chronic constipation, anorexia and cachexia) to drug absorption variability has not been firmly established yet. At the same time, a way to decrease oral drug pharmacokinetic variability is provided by the pharmaceutical industry: clinical evidence suggests that formulation approaches employed during drug development can decrease the variability in oral exposure. This review outlines the main drivers of oral drug exposure variability and potential approaches to overcome them, while highlighting existing knowledge gaps and guiding future studies in this area.

Drug delivery formulation impacts cyclosporine efficacy in a humanised mouse model of acute graft versus host disease

Acute graft versus host disease (aGvHD) is an allogeneic T cell mediated disease which manifests as a severe inflammatory disease affecting multiple organs including the liver, skin, lungs and gastrointestinal tract. Existing prophylactic and therapeutic approaches in aGvHD include the use of cyclosporine A (CyA), however the currently approved CyA formulations which were designed to optimise systemic CyA bioavailability can have a number of side effects including nephrotoxicity as well as the potential to attenuate the beneficial Graft-versus-Leukemia (GvL) effect. An added complication with CyA is that it has a narrow therapeutic window, and following oral administration is absorbed only from the small intestine, with variable cytochrome P450 metabolism contributing to intra- and inter-patient variability. This study sought to investigate the efficacy of a novel CyA oral formulation enabled by the integrated SmPill® oral drug delivery platform in a humanised mouse model of aGvHD. The study compared the approved optimised CyA (Neoral®) with SmPill®-enabled CyA and a systemic intravenous CyA formulation. Our findings clearly demonstrate superior efficacy of the novel SmPill® CyA in prolonging survival in a clinically relevant humanised aGvHD model. SmPill® CyA significantly reduced pathological score in the small intestine, colon, liver and lung of aGvHD mice. In addition, SmPill® CyA significantly reduced the levels of pro-inflammatory cytokines in all the GvHD target tissues examined. Notably, SmPill® CyA was significantly more potent in reducing GvHD associated pathology and inflammatory cytokine production compared to the optimised approved oral CyA formulation, Neoral®.

The role of ionic vs. non-ionic excipients in APIs-based eutectic systems

Aiming to contribute to drug pre-formulation, new eutectic mixtures were developed. Thymol, coumarin, or quaternary ammonium chlorides as excipients, were combined with the active pharmaceutical ingredients (APIs) acetylsalicylic acid, acetaminophen, ibuprofen, ketoprofen, or lidocaine. Their solid-liquid equilibrium (SLE) binary phase diagrams were measured to study eventual phase separation between the compounds, preventing manufacturing problems, and to study the molecular interactions between the APIs and ionic or non-ionic excipients. The Conductor-like Screening Model for Real Solvents (COSMO-RS) capability to predict the SLE of mixtures containing non-ionic excipients was further evaluated. COSMO-RS gives a good quantitative description of the experimental SLE being a tool with great potential in the screening of eutectic systems containing APIs and non-ionic excipients. While thymol presents strong interactions with the APIs, and consequently negative deviations to thermodynamic ideality, systems containing coumarin follow a quasi-ideal behavior. Regarding the ionic excipients, both choline chloride and the tetraalkylammonium chlorides are unable to establish relevant interactions with the APIs, and no significant negative deviations to ideality are observed. The liquefaction of the APIs here studied is favored by using non-ionic excipients, such as thymol, due to the strong interactions it can establish with the APIs.

Trans-urocanic acid enhances tenofovir alafenamide stability for long-acting HIV applications

Long-acting (LA) pre-exposure prophylaxis (PrEP) for HIV prevention is poised to address non-adherence and implementation challenges by alleviating the burden of user-dependent dosing. Due to its potency, tenofovir alafenamide (TAF) is a viable candidate for LA PrEP. However, the inherent hydrolytic instability of TAF presents a challenge for application in LA systems. In this work, we examined the mechanism of TAF hydrolysis in a reservoir-based implant system and characterized TAF degradation kinetics as a function of the solution pH. We determined a pH "stability window" between pH 4.8 - 5.8 in which TAF degradation is substantially mitigated, with minimal degradation at pH 5.3. In a pursuit of a TAF formulation suitable for LA PrEP, we studied trans-urocanic acid (UA) as a buffer excipient. Here we show that UA can maintain the pH of TAF free base (TAFfb) solution inside a surrogate implant model at approximately pH 5.4. Through in vitro analysis, we demonstrated preservation of released TAF purity above 90% for over 9 months. Further, we performed an in vivo assessment of TAFfb-UA formulation in a reservoir-based nanofluidic implant inserted subcutaneously in non-human primates. Preventive levels of tenofovir diphosphate above 100 fmol/106 peripheral blood mononuclear cells were achieved in 2 days and sustained over 35 days. Fluid retrieved from implants after 60 days of implantation showed that UA preserved the aqueous phase in the implant at ~ pH 5.5, effectively counteracting the neutralizing action of interstitial fluids. Moreover, residual TAF in the implants maintained > 98% purity. Overall, TAF-UA represents a viable formulation applicable for LA HIV PrEP.

Drug Formulation Impact on Prefilled Syringe Functionality and Autoinjector Performance

Given the surging interest in developing prefilled syringe and autoinjector combination products, investment in an early compatibility assessment is critical to prevent unwarranted drug/container closure interactions and avoid potential reformulation during late stages of drug development. In addition to the standard evaluation of drug stability, it is important to consider container closure functionality and overall device performance changes over time because of drug-container closure component interaction. This study elucidated the mechanisms that cause changes in syringe glide force over time and the impact on the injection duration. It was an expansion of the previous work, which indicated that drug formulation variables such as formulation excipients and pH affect syringe functionality over time. The current study described an investigative process for troubleshooting prolonged and variable autoinjector injection time caused by an increased syringe glide force variability over time. This increase in glide force variability stems from two root causes, namely plunger dimensional variation and syringe silicone oil change over time. The results demonstrated (a) the underlying factors of silicone oil change in the presence of drug formulation matrices, (b) accelerated stability of syringe glide force as a good indicator of long-term, real-time stability, and (c) that buffer matrix-filled syringes can be used to predict the syringe functionality and stability of drug product-filled syringes. Based on the experimental findings of a variety of orthogonal characterization techniques including contact angle, interfacial tension, and calculation of Hansen solubility parameters, it is proposed that silicone oil change is caused by formulation excipients and a complex set of phenomena summarized as "wet, wash, and delube" processes.

Determination of acidity constants for weak acids and bases by isothermal titration calorimetry

The advantage of isothermal titration calorimetry (ITC) to determine the acid dissociation constant (pK_a value) is the simultaneous determination of the binding constant and binding enthalpy, as well as being precise and easy to use. The pK_a can be calculated from the binding constant, and the temperature dependency of the pK_a can be calculated from the binding enthalpy. The use of ITC to study protonation reactions is less common compared to its more conventional use of studying macromolecules and ligands. Water will influence the equilibrium due to autoionization, meaning that both the conjugate base and acid will exist in the sample cell at the beginning of the experiment. These differences are accounted for by optimizing the theoretical model used to estimate the binding constant and binding enthalpy. Through simulations and experimental measurements, we show that ITC can be used to determine the pK_a for ibuprofen, ascorbic acid, 2-morpholin-4-ylethanesulfonic acid and paracetamol. The pK_a values were consistent with potentiometric or spectrophotometric determinations as well as literature values. Optimizing the theoretical model does not lead to an improved determination, so the "one set of sites" model is adequate for the determination of pK_a values.

Optimization of formulation for enhanced intranasal delivery of insulin with translationally controlled tumor protein-derived protein transduction domain

Intranasal delivery of insulin is an alternative approach to treat diabetes, as it enables higher patient compliance than conventional therapy with subcutaneously injected insulin. However, the use of intranasal delivery of insulin is limited for insulin’s hydrophilicity and vulnerability to enzymatic degradation. This limitation makes optimization of formulation intranasal insulin for commercial purpose indispensable. This study evaluated bioavailability (BA) of various formulations of insulin intranasally delivered with protein transduction domain (PTD) derived from translationally controlled tumor protein. The therapeutic efficacy of newly formulated intranasal insulin + PTD was compared in vivo studies with normal and alloxan-induced diabetic rats, to those of free insulin and subcutaneously injected insulin. BA of insulin in two new formulations was, respectively, 60.71% and 45.81% of subcutaneously injected insulin, while the BA of free insulin was only 3.34%. Histological analysis of tissues, lactate dehydrogenase activity in nasal fluid, and biochemical analysis of sera revealed no detectable topical or systemic toxicity in rats and mice. Furthermore, stability analysis of newly formulated insulin + PTD to determine the optimal conditions for storage revealed that when stored at 4 °C, the delivery capacity of insulin was maintained up to 7 d. These results suggest that the new formulations of intranasal insulin are suitable for use in diabetes therapy and are easier to administer.

Plant-derived bioadhesives for wound dressing and drug delivery system

Synthetic polymers have been widely used in various biomedical applications like drug delivery, wound dressing, etc. They pose a question of bio-compatibility and bio-accumulation, limiting to a minimum class of synthetic polymers to be efficient and versatile. Hence, one cheap and reliant replacement is the use of natural adhesives over the synthetic adhesive polymeric system. The pluripotency of plant could be exploit, making it a perfect candidate for extraction of plant-derived adhesives component for wound dressing and drug delivery system in large-scale production. Current advancement use excipients which influence, the rate of drug release and absorption. Properties like matrix formation and environment responsive gelation can be exploited through these plant-derived components for controlled drug release according to specific therapeutic requirement. This review explores such plant-derived bioactive component: Mucilage and gums, their isolation, and characterization which can be exploited as excipients in the formulation of drug delivery system as well as a wound dressing.

Long-Acting Growth Hormone Preparations in the Treatment of Children

Human growth hormone (hGH), which had been in use since 1958, was supplanted by recombinant human growth hormone (rhGH) in 1985 for those with growth hormone deficiency (GHD). Adherence to daily subcutaneous growth hormone is challenging for patients. Thus, several companies have pursued the creation of long acting rhGH. These agents can be divided broadly into depot formulations, PEGylated formulations, pro-drug formulations, non-covalent albumin binding GH and GH fusion proteins. Nutropin Depot is the only long acting rhGH ever approved by the U.S. Food and Drug Administration, and it was removed from the market in 2004. Of the approximately seventeen candidate drugs, only a handful remain under active clinical investigation or are commercially available.

Effect of solvent selection on drug loading and amorphisation in mesoporous silica particles

Increasing the dissolution rate of poorly water-soluble active pharmaceutical ingredients (APIs) is a key strategy used for improving their oral bioavailability. One of the formulation approaches is API loading to mesoporous carrier particles, which can increase the dissolution rate through the combination of improved powder wettability and dispersion, higher surface area, and API conversion from crystalline to the amorphous state. From the formulation process point of view, the maximum achievable drug loading is a crucial parameter, which depends on the loading method. Drug loading by sorption from a solution is a technologically attractive approach, since it involves familiar unit operations (mixing, filtration, drying). However, the success of the equilibrium sorption approach depends on the choice of the solvent. In this work we present an experimental study of loading efficiency to mesoporous silica particles, based on a set of 10 APIs combined with 6 different solvents at a range of concentrations. We show that due to the competitive nature of the adsorption process, the solvent with the highest API solubility is not necessarily the best candidate for maximising the API loading. Based on the investigated drug-solvent combinations, we show that the dielectric constant of the solvent is a good predictor of loading efficiency and can be used as a general guideline for solvent selection. On the other hand, we did not find any systematic correlation between commonly measured API properties such as logP and their loading efficiency.

Enhanced topical delivery of non-complexed molecular iodine for Methicillin-resistant Staphylococcus aureus decolonization

Staphylococcus aureus, a leading cause of serious human infections in both healthcare and community settings, is increasingly difficult to control due to expanding resistance to multiple antibiotic classes. Methicillin-resistant S. aureus (MRSA) strains have disseminated on a global scale and are associated with adverse patient outcomes, increased hospital stays, and significant economic costs to the healthcare system. A proximal step in S. aureus infection is colonization of the nasal mucosa, and effective strategies to decolonize high risk patients to reduce the risk of invasive infection and nosocomial spread represent an important clinical priority. With rising resistance to mupirocin, the most common antibiotic utilized for nasal MRSA decontamination, we are examining the use of pure molecular iodine (I₂)-based formulations for this indication. Recently, an iodophor formulation of povidone-iodine (PVP-I) has shown significant promise for nasal MRSA decontamination by swabbing the anterior nares of patients in hospital settings, but the I₂ concentration in this treatment is less than 0.01% of total iodine species present and like all providone-iodine formulations causes skin staining. Here we determine that a novel non-staining formulation of I₂ combined with the safe organic emollient glycerin delivers high local concentrations of the active antimicrobial entity (I₂) with minimal evaporative loss, exhibits activity at ∼1 part per million against MRSA and other important Gram-positive and -negative human pathogens. This formulation for I₂ topical delivery produced similar reductions in mean bacterial burden and was associated with fewer treatment failures (<2-logfold reduction) than PVP-I in a murine model of MRSA nasal decontamination. Formulations of I₂ in glycerin emollient merit further exploration as topical disinfectants for human medical indications.

Long-Term Constant Subcutaneous Drug Administration

In this chapter, a long-term drug delivery system for preclinical therapeutic research is introduced. By using a subcutaneously implanted ALZET^® osmotic pump, continuous zero-order delivery of drugs under investigation that need repeated oral or intravenous dosing is realizable. Compared to traditional delivery systems, implanted osmotic pumps present several advantages such as that no external connections or researcher intervention is required during infusion and that it is possible to save time by eliminating the need for frequent animal handling and repetitive injection schedules. Most importantly, a stable peripheral concentration of drug is able to be obtained using this constant drug delivery system, which would benefit researchers to verify the efficiency of antirheumatoid drugs and establish safety profiles in preclinical studies.

Challenges for pulmonary delivery of high powder doses

In recent years there is an increasing interest in the pulmonary delivery of large cohesive powder doses, i.e. drugs with a low potency such as antibiotics or drugs with a high potency that need a substantial fraction of excipient(s) such as vaccines stabilized in sugar glasses. The pulmonary delivery of high powder doses comes with unique challenges. For low potency drugs, the use of excipients should be minimized to limit the powder mass to be inhaled as much as possible. To achieve this objective the inhaler design should be adapted to the properties of the API in order to achieve a compatible combination of the drug formulation and inhaler device. The inhaler should have an appropriate powder dosing principle for which prefilled compartments seem most appropriate. The drug formulation should not only allow for accurate filling of these compartments but also enable efficient compartment emptying during inhalation. The dispersion principle must have the capacity to disperse considerable amounts of powder in a short time frame that allows the powder to reach the deep lung. Last, but not least, the inhaler should be simple and intuitive in use, be cost-effective and exhibit accurate and consistent, preferably patient independent, pulmonary delivery performance.

Antifungal Therapy in Birds: Old Drugs in a New Jacket

The use of antifungals in birds is characterized by interspecies and interindividual variability in the pharmacokinetics, affecting drug safety and efficacy. Oral antifungal drug absorption is a complex process affected by drug formulation characteristics, gastrointestinal anatomy, and physiology. New antifungal drug delivery systems can enhance drug stability, reduce off-target side effects, prolong residence time in the blood, and improve efficacy. Topical administration of antifungals through nebulization shows promising results. However, therapeutic output is highly influenced by drug formulation and type of nebulizer, indicating these factors should be taken into account when selecting this medication route.

Co-suspension delivery technology in pressurized metered-dose inhalers for multi-drug dosing in the treatment of respiratory diseases

Technologies for long-term delivery of aerosol medications in asthma and chronic obstructive pulmonary disease have improved over the past 2 decades with advancements in our understanding of the physical chemistry of aerosol formulations, device engineering, aerosol physics, and pulmonary biology. However, substantial challenges remain when a patient is required to use multiple inhaler types, multiple medications, and/or combinations of medications. Combining multiple drugs into a single inhaler while retaining appropriate dosing of the individual agents in the combination may enhance patient adherence to therapy and reduce device errors that occur when patients are using multiple inhalers. Pressurized metered-dose inhaler (pMDI) devices are widely used by patients for acute symptom relief as well as maintenance treatment, so the pMDI may be a suitable option with which to explore medication combinations. However, optimizing drug formulation remains a key challenge for pMDI delivery systems. This article introduces a new pMDI formulation approach: co-suspension delivery technology, which uses drug crystals with porous, low-density phospholipid particles engineered to deliver combinations of drugs to the airways with accurate and consistent dosing via pMDIs, independent of medication types and combinations. We describe the key characteristics of pMDIs, and discuss the rationale for the co-suspension delivery technology platform based on the limitations associated with traditional formulations. Finally, we discuss the clinical implications of co-suspension delivery technology for developing combination drug therapies administered by pMDIs.

Influence of route of administration/drug formulation and other factors on adherence to treatment in rheumatoid arthritis (pain related) and dyslipidemia (non-pain related)

OBJECTIVES

A comprehensive review was performed to investigate the effect of route of administration on medication adherence and persistence in rheumatoid arthritis (RA) and to compare adherence/persistence with oral medications between RA and a non-painful disease (dyslipidemia).

RESEARCH DESIGN AND METHODS

Comprehensive database searches were performed to identify studies investigating medication adherence and/or persistence in adults with RA receiving conventional synthetic or biologic agents. Similar searches were performed for studies of patients with dyslipidemia receiving statins. Studies had to be published after 1998 in English and involve ≥6 months' follow up.

MAIN OUTCOME MEASURES

Adherence and persistence were compared between the different routes of drug administration in RA, and between the two diseases for oral medications.

RESULTS

A total of 35 and 28 papers underwent data extraction for RA and dyslipidemia, respectively. Within the constraints of the analysis, adherence and persistence rates appeared broadly similar for the different routes of drug administration in RA. Adherence to oral medications was also broadly similar across the two diseases, but persistence was lower in dyslipidemia. Poor adherence has clinical consequences in both diseases: greater disease activity and risk of flare in RA, and increased serum cholesterol levels and risk of heart and cerebrovascular disease in dyslipidemia. Over 1-3 years, poor adherence to biologic RA medications led to increased resource use and medical costs but lower total direct costs due to reduced biologic drug costs. Conversely, poor adherence to dyslipidemia medications resulted in increased total direct costs. In both diseases, adherence improved with patient education/support.

CONCLUSIONS

The route of drug administration and the symptomatic (pain) nature of the disease do not appear to be dominant factors for drug adherence or persistence in RA.

LIMITATION

The wide range of adherence and persistence values and definitions across studies made comparisons between drug formulations and diseases difficult.

Soft, chewable gelatin-based pharmaceutical oral formulations: a technical approach

OBJECTIVE

Hard tablets and capsules for oral drug delivery cause problems for people experiencing dysphagia. This work describes the formulation and properties of a gelatin based, self-preserved, and soft chewable tablet as an alternative and novel drug delivery format.

MATERIALS AND METHODS

Gelatin (8.8-10% in 24.7-29% water) constituted the matrix of the soft, semi-solid tablets. Three different pharmaceuticals (Ibuprofen 10%, Acetaminophen 15%, and Meloxicam 1.5%) were tested in this formulation. Microbial stability was controlled by lowering the water activity with a mixture of sorbitol and xylitol (45.6-55%). Rheological properties were tested applying small strain oscillation measurements. Taste masking of ibuprofen soft-chew tablets was achieved by keeping the ibuprofen insoluble at pH 4.5 and keeping the processing temperature below the crystalline-to-amorphous transition temperature.

RESULTS

Soft-chew formulations showed good stability for all three pharmaceuticals (up to 24 months), and the ibuprofen containing formulation exhibited comparable dissolution to a standard oral tablet as well as good microbial stability. The rheological properties of the ibuprofen/gelatin formulation had the fingerprint of a true gelatin gel, albeit higher moduli, and melting temperature.

CONCLUSIONS

The results suggest that easy-to-swallow and well taste-masked soft chewable tablet formulations with extended shelf life are within reach for several active pharmaceutical ingredients (APIs).

Lanreotide Depot: An Antineoplastic Treatment of Carcinoid or Neuroendocrine Tumors

Purpose

Peptide drugs for antineoplastic therapies usually have low oral bioavailability and short in vivo half-lives, requiring less preferred delivery methods. Lanreotide depot is a sustained-release somatostatin analog (SSA) formulation produced via an innovative peptide self-assembly method. Lanreotide is approved in the USA and Europe to improve progression-free survival (PFS) in patients with unresectable gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and also approved in Europe for symptom control in carcinoid syndrome associated with GEP-NETs. This review discusses how the distinct molecule and formulation of lanreotide depot provide advantages to patients and health care providers, as well as the most recent clinical evidence demonstrating the safety and efficacy of lanreotide depot in inhibiting tumor growth and controlling hormonal symptoms in GEP-NETs.

Methodology and Results

The lanreotide depot formulation confers a remarkable pharmacokinetic profile with no excipients, comprised only of lanreotide acetate and water. Of note, lanreotide depot constitutes an example for peptide self-assembly based formulations, providing insights that could help future development of sustained-release formulations of other antineoplastic peptides. Most patients with GEP-NETs will present with inoperable or incurable disease; thus, medical management for symptoms and tumor control plays a crucial role. Recent long-term clinical studies have demonstrated that lanreotide depot is well tolerated, prolongs PFS in GEP-NET patients, and significantly reduces symptoms related to carcinoid syndrome.

Conclusions

The unique depot formulation and delivery method of lanreotide confer advantages in the treatment of metastatic GEP-NETs, contributing to improvements in NET-related symptoms and PFS without reducing quality of life in this patient population.

Pharmacokinetics and pharmacogenetics of 13-cis retinoic acid in Indian high-risk neuroblastoma patients

PURPOSE

To compare the pharmacokinetics of 13-cis retinoic acid (13-cisRA) between Indian and UK neuroblastoma patients receiving comparable treatment, alongside measures of toxicity and response.

METHODS

13-cisRA (160 mg/m(2)/day) was administered to 36 patients ≤16 years in two divided doses. Plasma 13-cisRA concentrations were determined on days 1 and 14 of cycles 1 and 4 of treatment. Area under the plasma concentration-time curve (AUC0-6h) was estimated using non-compartment modelling. Patients were genotyped for UGT2B7, CYP3A5*3, CYP3A7*2 and *2, *3 and *4 variants of CYP2C8.

RESULTS

Marked inter-patient variability in 13-cisRA pharmacokinetics was observed. There was a trend towards a higher AUC0-6h on day 1 versus day 14 for both treatment cycles studied. Children who swallowed 13-cisRA capsules (n = 18) achieved higher AUC0-6h values compared to those who could not (n = 16) (Mean AUC 21.53 vs. 9.35 µM h, P < 0.05). Patients who were event free at 1 year tended to have higher AUC0-6h on C1D1 compared to those patients who progressed, although this did not reach significance with the number of patients studied (P = 0.08). Similarly, patients who achieved a 13-cisRA C max of ≥2 µM on C1D1 tended to have higher median EFS compared to those who did not (17.0 vs. 8.1 months). UGT2B7, CYP2C8*2/*3/*4 or CYP3A5*3 genotype did not have any effect on 13-cisRA pharmacokinetics.

CONCLUSIONS

Method of administration markedly affects 13-cisRA pharmacokinetics in Indian neuroblastoma patients, supporting similar findings in UK patients. An appropriate oral liquid formulation of 13-cisRA that can be administered to all children with neuroblastoma is urgently needed on an international level.

Oral dosage form administration practice in children under 6 years of age: A survey study of paediatric nurses

The purpose of this study was to interview paediatric nurses on administration issues using extemporaneous capsules and marketed capsules and tablets in children younger than 6 years old, based on most frequently administered drugs in six participating wards. The 59 responding nurses estimated respectively at 7.7±1.7 and 7.3±1.8years the age from which children would properly swallow extemporaneous capsules and marketed solids, with 33% and 37% of nurses considering that children under 6 would not get their prescribed treatment using these dosage forms. Refusal of the child to take the solid was the first reason to explain administration failure (85% of nurses for extemporaneous capsules, 89% for marketed solids). Although type of formulation and requirement of chewing were factors influencing the age at which children would take solid from nurses' experience, size of conventional tablets was not among these factors. All respondents use to crush tablets in children unable to swallow whole solids; 37% of nurses systematically split the tablets to ease the swallowing in children able to swallow. Only 11 nurses had an information tool at their disposal to guide manipulation of solids, with 7 of them using it in their daily practice. Providing specific-ward questionnaires, this study gives factual information on administration practices, perceptions and issues faced by paediatric nurses.

Probing adsorption of DSPE-PEG2000 and DSPE-PEG5000 to the surface of felodipine and griseofulvin nanocrystals

Nanosized formulations of poorly water-soluble drugs show great potential due to improved bioavailability. In order to retain colloidal stability, the nanocrystals need to be stabilized. Here we explore the use of the poly(ethylene glycol) (PEG) conjugated phospholipids DSPE-PEG2000 and DSPE-PEG5000 as stabilizers of felodipine and griseofulvin nanocrystals. Nanocrystal stability and physicochemical properties were examined and the interaction between the PEGylated lipids and the nanocrystal surface as well as a macroscopic model surface was investigated. Using quartz crystal microbalance with dissipation monitoring both mass adsorption and the thickness of the adsorbed layer were estimated. The results indicate that the PEGylated lipids are adsorbed as flat layers of around 1-3nm, and that DSPE-PEG5000 forms a thicker layer compared with DSPE-PEG2000. In addition, the mass adsorption to the drug crystals and the model surface are seemingly comparable. Furthermore, both DSPE-PEG2000 and DSPE-PEG5000 rendered stable drug nanocrystals, with a somewhat higher surface binding and stability seen for DSPE-PEG2000. These results suggest DSPE-PEG2000 and DSPE-PEG5000 as efficient nanocrystal stabilizers, with DSPE-PEG2000 giving a somewhat higher surface coverage and superior colloidal stability, whereas DSPE-PEG5000 shows a more extended structure that may have advantages for prolongation of circulation time in vivo and facilitation for targeting modifications.

Regulatory development of geriatric medicines: To GIP or not to GIP?

Geriatric patients represent the main users of medicines, but are historically often minimally included in clinical trials, resulting in a gap in the knowledge of the benefit/risk balance of medicines in this heterogeneous population. As the worldwide population is aging, the need for safe and effective medicines for older patients is proportionally increasing. The aim of this review is to provide an overview of the current regulatory status of the development of geriatric medicines, the encountered challenges and the view of the involved stakeholders, coming to the conclusion whether it is necessary or not to implement a Geriatric Investigation Plan (GIP), by analogy with pediatrics.

Oral drug dosage forms administered to hospitalized children: Analysis of 117,665 oral administrations in a French paediatric hospital over a 1-year period

Selecting the most appropriate dosage form, that ensures safe administration and adherence of medications, is a major issue for children. Marketed drugs, however, have rarely been tested for their use in children. There is a need for more data on drug formulations administered to children to identify unmet needs, and drive future paediatric research. We observed, over a 12-month follow-up, 117,665 oral drug administrations to 1998 hospitalized children. Nine-tenths belonged to five Anatomical Therapeutic Chemical classes: Alimentary tract & metabolism, Nervous system, Cardiovascular system, Anti-infectives for systemic use and Blood & blood forming organs, one third of drug doses administered to school-age children and adolescents were liquids, and extemporaneous capsules were commonly used in younger children. Our study shows that despite the advantages of solid dosage forms and recent evidence from randomized controlled trials showing their acceptability in infants, they are seldom used in paediatric practice.

Low-Transition-Temperature Mixtures (LTTMs) for Dissolving Proteins and for Drug Formulation

Several diverse proteins are found to readily dissolve in neat low-transition-temperature mixtures (LTTMs). They undergo no irreversible denaturation in such unusual solvents, and the resistance of hen egg-white lysozyme against thermoinactivation in LTTMs is greater than in aqueous solution at extreme pHs. Separately, the water-sensitive drug aspirin is found to form concentrated transparent LTTMs, where it is some 10-fold more stable against cleavage than in water.

Safety and pharmacodynamics of suprachoroidal injection of triamcinolone acetonide as a controlled ocular drug release model

Suprachoroidal injection is an emerging technique for drug delivery to the posterior segment, which is hard to reach by non-invasive approaches. However, the injection technique varies and the associated ocular safety is not well understood. In addition, it is not clear if drug formulation is a major factor in optimizing pharmacodynamics using this technique. The current study was designed to compare the suprachoroidal injection of different drug formulations and to characterize the safety and pharmacodynamics of triamcinolone acetonide (TA) delivered by this technique. Both indocyanine green (ICG) solution and TA suspension, at 50μL, 100μL, and 150μL, were suprachoroidally injected and intraocular pressure (IOP) tonometry, fundus photography, and electroretinography were performed over multiple time points up to eight weeks. After 50μL TA (Kenalog-40) suprachoroidal injection, 4-5 animals at 7 time points were sacrificed for aqueous, vitreous, retina, and plasma collections. TA was quantitated using ultra-performance liquid chromatography tandem mass spectrometry. For comparative efficacy study, 50μL (2mg) suprachoroidal TA versus 20mg subtenon TA were performed 4weeks before induction of experimental uveitis with 10ng of intravitreal lipopolysaccharide. After suprachoroidal injection, IOP had an acute elevation, higher volume caused higher IOP (p<0.0001). Equivalent volume of ICG solution led to a significantly smaller IOP elevation than after TA suprachoroidal injection. This finding suggests better distribution of ICG solution than TA suspension in the suprachoroidal space. Following a 50μL suprachoroidal injection, peak TA concentration in the aqueous was below 1ng/mL. In contrast, the posterior vitreous and retina had 1912ng/mL and 400,369ng/mL TA, respectively. Maximum TA in plasma was 11.6ng/mL. Drug exposure to the posterior retina was 523,910 times more than that to the aqueous and 29,516 times more than systemic TA exposure. In the treatment of lipopolysaccharide-induced uveitis, compared with 20mg subtenon injection, suprachoroidal 2mg TA demonstrated much better efficacy with significantly less aqueous humor cells and lower vitreous opacity scores (p<0.05). Histology showed much less vitreous inflammation in the suprachoroidal injection group (p<0.0001). It seems that a 50μL suprachoroidal injection of TA was well tolerated in rabbit eyes and demonstrated excellent penetration into the posterior retina, providing better therapeutic effect than subtenon 20mg TA.

Formulation and delivery of anti-HIV rectal microbicides: advances and challenges

Men and women engaged in unprotected receptive anal intercourse (RAI) are at higher risk of acquiring HIV from infected partners. The implementation of preventive strategies is urgent and rectal microbicides may be a useful tool in reducing the sexual transmission of HIV. However, pre-clinical and first clinical trials have been able to identify limitations of candidate products, mostly related with safety issues, which can in turn enhance viral infection. Indeed, the development of suitable formulations for the rectal delivery of promising antiretroviral drugs is not an easy task, and has been mostly based on products specifically intended for vaginal delivery, but these have been shown to provide sub-optimal outcomes when administered rectally. Research and development in the rectal microbicide field are now charting their own path and important information is now available. In particular, specific formulation requirements of rectal microbicide products that need to be met have just recently been acknowledged despite additional work being still required. Desirable rectal microbicide product features regarding characteristics such as pH, osmolality, excipients, dosage forms, volume to be administered and the need for applicator use have been studied and defined in recent years, and specific guidance is now possible. This review provides a synopsis of the field of rectal microbicides, namely past and ongoing clinical studies, and details on formulation and drug delivery issues regarding the specific development of rectal microbicide products. Also, future work, as required for the advancement of the field, is discussed.

Fatty acids as therapeutic auxiliaries for oral and parenteral formulations

Many drugs have decreased therapeutic activity due to issues with absorption, distribution, metabolism and excretion. The co-formulation or covalent attachment of drugs with fatty acids has demonstrated some capacity to overcome these issues by improving intestinal permeability, slowing clearance and binding serum proteins for selective tissue uptake and metabolism. For orally administered drugs, albeit at low level of availability, the presence of fatty acids and triglycerides in the intestinal lumen may promote intestinal uptake of small hydrophilic molecules. Small lipophilic drugs or acylated hydrophilic drugs also show increased lymphatic uptake and enhanced passive diffusional uptake. Fatty acid conjugation of small and large proteins or peptides has exhibited protracted plasma half-lives, site-specific delivery and sustained release upon parenteral administration. These improvements are most likely due to associations with lipid-binding serum proteins, namely albumin, LDL and HDL. These molecular interactions, although not fully characterized, could provide the ability of using the endogenous carrier systems for improving therapeutic outcomes.

Molecular approaches towards development of purified natural products and their structurally known derivatives as efficient anti-cancer drugs: current trends

Several natural products and their derivatives, either in purified or structurally identified form, exhibit immense pharmacological and biological properties, some of them showing considerable anticancer potential. Although the molecular mechanisms of action of some of these products are yet to be elucidated, extensive research in this area continues to generate new data that are clinically exploitable. Recent advancement in molecular biology, high throughput screening, biomarker identifications, target selection and genomic approaches have enabled us to understand salient interactions of natural products and their derivatives with cancer cells vis-à-vis normal cells. In this review we highlight the recent approaches and application of innovative technologies made to improve quality as well as efficiency of structurally identified natural products and their derivatives, particularly in small molecular forms capable of being used in "targeted therapies" in oncology. These products preferentially involve multiple mechanistic pathways and overcome chemo-resistance in tumor types with cumulative action. We also mention briefly a few physico-chemical features that compare natural products with drugs in recent natural product discovery approaches. We further report here a few purified natural products as examples that provide molecular interventions in cancer therapeutics to give the reader a glimpse of the current trends of approach for discovering useful anticancer drugs.

Neonates need tailored drug formulations

Drugs are very strong tools used to improve outcome in neonates. Despite this fact and in contrast to tailored perfusion equipment, incubators or ventilators for neonates, we still commonly use drug formulations initially developed for adults. We would like to make the point that drug formulations given to neonates need to be tailored for this age group. Besides the obvious need to search for active compounds that take the pathophysiology of the newborn into account, this includes the dosage and formulation. The dosage or concentration should facilitate the administration of low amounts and be flexible since clearance is lower in neonates with additional extensive between-individual variability. Formulations need to be tailored for dosage variability in the low ranges and also to the clinical characteristics of neonates. A specific focus of interest during neonatal drug development therefore is a need to quantify and limit excipient exposure based on the available knowledge of their safety or toxicity. Until such tailored vials and formulations become available, compounding practices for drug formulations in neonates should be evaluated to guarantee the correct dosing, product stability and safety.

Aqueous solubility: simple predictive methods (in silico, in vitro and bio-relevant approaches)

Aqueous solubility is a key physicochemical attribute required for the characterisation of an active pharmaceutical ingredient (API) during drug discovery and beyond. Furthermore, aqueous solubility is highly important for formulation selection and subsequent development processes. This review provides a summary of simple predictive methods used to assess aqueous solubility as well as an assessment of the more complex in silico methodologies and a review of the recent solubility challenge. In addition, a summary of experimental methods to determine solubility is included, with a discussion of some potential pitfalls.

Compliance and Caregiver Satisfaction in Alzheimer's Disease: Results from the AXEPT Study

Background/Aims

According to experimental data, a transdermal application is preferred by caregivers of Alzheimer's disease (AD) patients compared with oral medications. The AXEPT study compared compliance to treatment among community-dwelling patients with mild-to-moderate AD treated with transdermal application compared to oral medications and caregiver satisfaction in a real clinical setting.

Methods

Data from 45 memory clinics in Italy were collected between September 8, 2010 and January 31, 2011. Compliance to treatment and caregiver satisfaction were measured using the Caregiver Medication Interview.

Results

A total of 855 AD patients and their caregivers participated in the study. Nearly 80% of caregivers of patients on patch were not concerned about adherence to treatment compared with 64% of caregivers of patients on oral drugs. Among caregivers of patients on patch, 94% did not report any difficulties in remembering to administer treatment compared with 73% of caregivers of patients on oral medications. The highest level of compliance and satisfaction was reported by caregivers of patients on transdermal application.

Conclusion

Caregivers of patients treated with a transdermal application appeared to be more satisfied and reported a higher level of compliance than caregivers of patients receiving anti-AD oral medications.

Protection of the liver against CCl4-induced injury by intramuscular electrotransfer of a kallistatin-encoding plasmid

AIM: To investigate the effect of transgenic expression of kallistatin (Kal) on carbon tetrachloride (CCl₄)-induced liver injury by intramuscular (im) electrotransfer of a Kal-encoding plasmid formulated with poly-L-glutamate (PLG).

METHODS: The pKal plasmid encoding Kal gene was formulated with PLG and electrotransferred into mice skeletal muscle before the administration of CCl₄. The expression level of Kal was measured. The serum biomarker levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), malonyldialdehyde (MDA), and tumor necrosis factor (TNF)-α were monitored. The extent of CCl₄-induced liver injury was analyzed histopathologically.

RESULTS: The transgene of Kal was sufficiently expressed after an im injection of plasmid formulated with PLG followed by electroporation. In the Kal gene-transferred mice, protection against CCl₄-induced liver injury was reflected by significantly decreased serum ALT, AST, MDA and TNF-α levels compared to those in control mice (P < 0.01 to 0.05 in a dose-dependent manner). Histological observations also revealed that hepatocyte necrosis, hemorrhage, vacuolar change and hydropic degeneration were apparent in mice after CCl₄ administration. In contrast, the damage was markedly attenuated in the Kal gene-transferred mice. The expression of hepatic fibrogenesis marker transforming growth factor-β1 was also reduced in the pKal transferred mice.

CONCLUSION: Intramuscular electrotransfer of plasmid pKal which was formulated with PLG significantly alleviated the CCl₄-induced oxidative stress and inflammatory response, and reduced the liver damage in a mouse model.

Situation in treatment of ulcerative colitis by Chinese and Western medicine

In recent years, the incidence of ulcerative colitis (UC) has been increasing. The lesions may involve the rectum, sigmoid colon, left colon (distal spleen curve area), proximal colon spleen curve area, and even the whole colon. Drug formulations should be different according to the involved scopes. This article reviews and summarizes the advancements of Chinese and Western drug formulations in treating UC, and discusses the great significance in choosing drug formulations for improvement of the disease and the life quality of patients.