Adverse drug events related to dosage forms and delivery systems

Challenges in the Development of Intravenous Neurokinin-1 Receptor Antagonists: Results of a Safety and Pharmacokinetics Dose-Finding, Phase 1 Study of Intravenous Fosnetupitant

Oral NEPA is the fixed-combination antiemetic comprising netupitant (neurokinin-1 receptor antagonist [NK₁ RA]) and palonosetron (5-hydroxytryptamine-3 receptor antagonist [5-HT₃ RA]). Intravenous (IV) NEPA, containing fosnetupitant, a water-soluble N-phosphoryloxymethyl prodrug of netupitant, has been developed. Fosnetupitant does not require excipients or solubility enhancers often used to increase IV NK₁ RA water solubility, preventing the occurrence of hypersensitivity and infusion-site reactions associated with these products. In this phase 1 study, subjects received a 30-minute placebo or fosnetupitant (17.6-353 mg) infusion and an oral NEPA or placebo capsule, with 2-sequence crossover treatment for fosnetupitant 118- to 353-mg dose cohorts. IV fosnetupitant safety and pharmacokinetics were evaluated, and its equivalence to an oral netupitant 300-mg dose was defined. Overall, 158 healthy volunteers were enrolled. All adverse events (AEs) were mild or moderate in intensity. Doppler-identified infusion-site asymptomatic thrombosis occurred in 5.4% (fosnetupitant) and 1.2% (oral NEPA) of subjects. The frequency or number of treatment-related AEs did not increase with ascending fosnetupitant doses. The most common treatment-related AEs were headache (fosnetupitant, 8.1%; oral NEPA, 12.7%) and constipation (fosnetupitant, 1.4%; oral NEPA, 7.5%). A fosnetupitant 235-mg dose was equivalent, in terms of netupitant exposure, to 300-mg oral netupitant. The safety profile of a single fosnetupitant 235-mg infusion was similar to that of single-dose oral NEPA.

Surface Engineered Iron Oxide Nanoparticles Generated by Inert Gas Condensation for Biomedical Applications

Despite the lifesaving medical discoveries of the last century, there is still an urgent need to improve the curative rate and reduce mortality in many fatal diseases such as cancer. One of the main requirements is to find new ways to deliver therapeutics/drugs more efficiently and only to affected tissues/organs. An exciting new technology is nanomaterials which are being widely investigated as potential nanocarriers to achieve localized drug delivery that would improve therapy and reduce adverse drug side effects. Among all the nanocarriers, iron oxide nanoparticles (IONPs) are one of the most promising as, thanks to their paramagnetic/superparamagnetic properties, they can be easily modified with chemical and biological functions and can be visualized inside the body by magnetic resonance imaging (MRI), while delivering the targeted therapy. Therefore, iron oxide nanoparticles were produced here with a novel method and their properties for potential applications in both diagnostics and therapeutics were investigated. The novel method involves production of free standing IONPs by inert gas condensation via the Mantis NanoGen Trio physical vapor deposition system. The IONPs were first sputtered and deposited on plasma cleaned, polyethylene glycol (PEG) coated silicon wafers. Surface modification of the cleaned wafer with PEG enabled deposition of free-standing IONPs, as once produced, the soft-landed IONPs were suspended by dissolution of the PEG layer in water. Transmission electron microscopic (TEM) characterization revealed free standing, iron oxide nanoparticles with size < 20 nm within a polymer matrix. The nanoparticles were analyzed also by Atomic Force Microscope (AFM), Dynamic Light Scattering (DLS) and NanoSight Nanoparticle Tacking Analysis (NTA). Therefore, our work confirms that inert gas condensation by the Mantis NanoGen Trio physical vapor deposition sputtering at room temperature can be successfully used as a scalable, reproducible process to prepare free-standing IONPs. The PEG- IONPs produced in this work do not require further purification and thanks to their tunable narrow size distribution have potential to be a powerful tool for biomedical applications.

Developing a framework regarding a complex risk based methodology in the evaluation of hazards associated with medicinal products sourced via the internet

Today, the increasing number of illicit internet pharmacies is a global phenomenon, however, the size of the online pharmaceutical market is still relatively unknown and the dubious quality of products is questionable and warrants investigation. Descriptive data from this black market channel are derived from studies analyzing the online availability of different medications procured over the internet and their methodology is quite heterogeneous. Our aim was to develop a comprehensive and specific risk assessment for selecting high patient safety risk medications from the online pharmaceutical market. A rapid tool was developed based upon the two quality and safety standard resolutions in pharmaceutical practice, published by the European Directorate for the Quality of Medicines, and was illustrated on eye drops. We developed five dimensions in support of the risk assessment including intrinsic, extrinsic and potential risks of counterfeiting. The five criteria were integrated in a comprehensively weighted risk-scoring format. The probability of procuring the product from the internet was also assessed based on the number of relevant links within the first twenty search engine results and the cost of the products. With the application of the tool a dorzolamide & timolol combination eye drop represented the highest overall patient safety risk score. In consideration of our literature review of the past 20 years, there is no current, standardized methodology to effectively identify pharmaceutical products associated with high patient safety risks. Notably, the fully comprehensive analysis of the internet pharmaceutical market and the test purchase of all online available medicines is unrealistic. Therefore, we developed a method to aid online surveillance researches and targeted international organizational led joint actions against the uncontrolled sale of falsified and substandard medications (e.g.: Operation Pangea).

Development of an adverse drug event network to predict drug toxicity

Despite of their therapeutic effects, drug's exposure may have negative effects on human health such as adverse drug reaction (ADR) and side effects (SE). Adverse drug events (ADEs), that correspond to an event occurring during the drug treatment (i.e. ADR and SE), is not necessarily caused by the drug itself, as this is the case with medical errors and social factors. Due to the complexity of the biological systems, not all ADEs are known for marketed drugs. Therefore, new and effective methods are needed to determine potential risks, including the development of computational strategies. We present an ADE association network based on 90,827 drug-ADE associations between 930 unique drug and 6221 unique ADE, on which we implemented a scoring system based on a pull-down approach for prediction of drug-ADE combination. Based on our network, ADEs proposed for three drugs, safinamide, sonidegib, rufinamide are further discussed. The model was able to identify, already known drug-ADE associations that are supported by the literature and FDA reports, and also to predict uncharacterized associations such as dopamine dysregulation syndrome, or nicotinic acid deficiency for the drugs safinamide and sonidegib respectively, illustrating the power of such integrative toxicological approach.

Hydrotropic polymer micelles as versatile vehicles for delivery of poorly water-soluble drugs

Polymer micelles have been used widely for delivery of poorly water-soluble drugs. Such drug delivery, however, has been based primarily on hydrophobic interactions. For better drug loading and improved stability, hydrotropic polymer micelles were used. To develop a versatile polymer micelle for solubilizing various poorly soluble drugs, two different hydrotropic agents were examined. The solubilizing properties of two hydrotropic agents, N,N-diethylnicotinamide (DENA) and N,N-dimethylbenzamide (DMBA), in polymeric form were investigated for their ability to solubilize five drugs with low aqueous solubility covering a wide range of hydrophobicity and molecular structures. The hydrotropes were covalently linked to the hydrophobic block of a block copolymer that also had a hydrophilic poly(ethylene glycol) (PEG) block. The solubilizing capacity of the polymeric hydrotropes was compared with that of the non polymeric hydrotropes, as well as of two conventional (non hydrotropic) copolymer systems. The solubilizing capacity of polymeric hydrotropes reflects combined effects of the micellar solubilization by the hydrophobic micelle core and hydrotropic solubilization. Because of the highly localized configuration, hydrotropes in the polymeric form are more powerful solubilizers than in the monomeric (non-polymeric) solution. It is possible to produce 1~3 orders of magnitude increase in solubility with polymeric hydrotropes at the 1% (w/v) level. Of the two hydrotropic polymeric systems in this study, the DENA-based system is highly specific, whereas the DMBA-based system is a general solubilizer of hydrophobic drugs. An additional advantage of polymeric hydrotropes over the non-polymeric form is absence of high concentrations of free hydrotropes in the formulation. Solubilization vehicles based on polymeric hydrotropes are expected to provide a new and versatile means of preparing formulations for various poorly soluble drugs and drug candidates without using organic solvents. This advantage is accompanied with the inherent controlled release property of the hydrotropic polymer micelles, making them ideal for pharmaceutical formulations used in drug candidate screening and toxicology studies.

Concentration-dependent toxicity of iron oxide nanoparticles mediated by increased oxidative stress

Iron oxide nanoparticles with unique magnetic properties have a high potential for use in several biomedical, bioengineering and in vivo applications, including tissue repair, magnetic resonance imaging, immunoassay, drug delivery, detoxification of biologic fluids, cell sorting, and hyperthermia. Although various surface modifications are being done for making these nonbiodegradable nanoparticles more biocompatible, their toxic potential is still a major concern. The current in vitro study of the interaction of superparamagnetic iron oxide nanoparticles of mean diameter 30 nm coated with Tween 80 and murine macrophage (J774) cells was undertaken to evaluate the dose- and time-dependent toxic potential, as well as investigate the role of oxidative stress in the toxicity. A 15–30 nm size range of spherical nanoparticles were characterized by transmission electron microscopy and zeta sizer. MTT assay showed >95% viability of cells in lower concentrations (25–200 μg/mL) and up to three hours of exposure, whereas at higher concentrations (300–500 μg/mL) and prolonged (six hours) exposure viability reduced to 55%–65%. Necrosis-apoptosis assay by propidium iodide and Hoechst-33342 staining revealed loss of the majority of the cells by apoptosis. H₂DCFDDA assay to quantify generation of intracellular reactive oxygen species (ROS) indicated that exposure to a higher concentration of nanoparticles resulted in enhanced ROS generation, leading to cell injury and death. The cell membrane injury induced by nanoparticles studied using the lactate dehydrogenase assay, showed both concentration- and time-dependent damage. Thus, this study concluded that use of a low optimum concentration of superparamagnetic iron oxide nanoparticles is important for avoidance of oxidative stress-induced cell injury and death.

Nanohybrids for controlled antibiotic release in topical applications

New polymeric composite materials containing a nanohybrid to be used for the controlled release of an antibiotic molecule, chloramphenicol succinate, have been formulated, prepared and characterised. The nanohybrid consists of a layered double hydroxide of Mg-Al hydrotalcite-type, in which the nitrate anions present in the host galleries were replaced with chloramphenicol succinate anions (CFS(-)) by a simple ion-exchange reaction. Different amounts of the hybrid material were incorporated in polycaprolactone and processed as films of 0.15mm thickness. The composite materials were analysed by X-ray diffractometry and thermogravimetry and their mechanical properties were determined. They showed properties even better than those of the pristine polymer. The release process of the antibiotic molecules was found to be very interesting and promising for tuneable drug delivery. It consists of two stages: an initial stage of a very rapid burst, in which a small fraction of drug is released; and a second stage that is much slower, extending for a longer and longer time. This behaviour is profoundly different and much slower than that of a sample in which the antibiotic molecule is directly incorporated into the polymeric matrix. The parameters influencing drug release have been individuated and discussed.

Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles (SPION) with appropriate surface chemistry have been widely used experimentally for numerous in vivo applications such as magnetic resonance imaging contrast enhancement, tissue repair, immunoassay, detoxification of biological fluids, hyperthermia, drug delivery and in cell separation, etc. All these biomedical and bioengineering applications require that these nanoparticles have high magnetization values and size smaller than 100 nm with overall narrow particle size distribution, so that the particles have uniform physical and chemical properties. In addition, these applications need special surface coating of the magnetic particles, which has to be not only non-toxic and biocompatible but also allow a targetable delivery with particle localization in a specific area. To this end, most work in this field has been done in improving the biocompatibility of the materials, but only a few scientific investigations and developments have been carried out in improving the quality of magnetic particles, their size distribution, their shape and surface in addition to characterizing them to get a protocol for the quality control of these particles. Nature of surface coatings and their subsequent geometric arrangement on the nanoparticles determine not only the overall size of the colloid but also play a significant role in biokinetics and biodistribution of nanoparticles in the body. The types of specific coating, or derivatization, for these nanoparticles depend on the end application and should be chosen by keeping a particular application in mind, whether it be aimed at inflammation response or anti-cancer agents. Magnetic nanoparticles can bind to drugs, proteins, enzymes, antibodies, or nucleotides and can be directed to an organ, tissue, or tumour using an external magnetic field or can be heated in alternating magnetic fields for use in hyperthermia. This review discusses the synthetic chemistry, fluid stabilization and surface modification of superparamagnetic iron oxide nanoparticles, as well as their use for above biomedical applications.

Optimising the therapeutic trinity of active ingredient, delivery system and functional packaging

This paper introduces the "therapeutic trinity" concept for formulating and developing optimal drug products. It starts with the recognition that all drug products are constituted of three distinct elements: the active ingredient, the delivery system and the packaging. Union of these three elements into one trinity will bring therapeutic value to the patient under the condition that active ingredient, delivery system and packaging are developed and optimised interdependently. Optimisation should be performed with the patient in mind, taking into account the relevant efficacy and safety parameters, and the relevant quality and cost parameters. Since the patient plays the central role in the performance of the drug product, biopharmaceutical robustness of and patient compliance towards the active ingredient/delivery system/packaging trinity should be considered important determinants of therapeutic success.

Gastrointestinal safety of an extended-release, nondeformable, oral dosage form (OROS: a retrospective study

BACKGROUND

The OROS osmotic (OSM) dosage form optimises extended-release oral administration by controlling the rate of drug release for a predetermined time, providing constant, patterned, or pulsed delivery profiles. OSM products include prescription medications for urology, CNS, and cardiovascular indications, as well as over-the-counter nasal/sinus congestion medications.

METHODS

This retrospective study examines US gastrointestinal (GI) safety data for the OROS dosage form following nearly two decades of use. Although GI injury and obstruction are known effects of oral medications, some reports have suggested that extended-release products pose a greater risk of GI injury and obstruction than other oral dosage forms. Products incorporating OROS technology are being prescribed to an expanding range of patients; a review of the GI safety data for this dosage form thus seemed timely and appropriate. US safety information was obtained from three sources: English language literature published from 1982 until June 1, 2000 from five major biomedical databases;postmarketing safety reports from January 1, 1983 until June 1, 2000 available through the Freedom of Information Act; andcommercial safety information obtained directly from ALZA Corporation's in-house safety database for those OSM products for which ALZA has reporting responsibility. US distribution data from IMS National Prescription Audit trade mark Plus data were used to estimate cumulative product distribution totals. These totals were combined with numbers of unique GI events to determine the estimated frequency of events.

RESULTS

Nearly 13 billion OSM tablets are estimated to have been distributed in the US. The incidence of all clinically significant GI adverse events for OSM products (including intestinal, gastric, and oesophageal irritation, injury, and obstruction) reported in the US was approximately one case in >76 million tablets distributed. The majority (78%; estimated incidence: one case in 29 million tablets) of cases were reported in patients taking Procardia XL (nifedipine). Oesophageal and lower GI obstruction were reported primarily in patients with pre-existing abnormalities or disease of the GI tract. Among paediatric patients, one obstruction was reported in an estimated 37.7 million tablets distributed. Reports of GI irritation associated with OSM products were consistent with known effects of the same drug substances in other dosage forms.

CONCLUSION

A review of long-term safety experience with products using OSM controlled-release technology yields a low incidence of clinically significant GI events. Properly prescribed, extended-release products provide substantial therapeutic and convenience benefits without additional risk.