Formulation-related problems associated with intravenous drug delivery

Advancements in Skin-Mediated Drug Delivery: Mechanisms, Techniques, and Applications

Skin-mediated drug delivery methods currently are receiving significant attention as a promising approach for the enhanced delivery of drugs through the skin. Skin-mediated drug delivery offers the potential to overcome the limitations of traditional drug delivery methods, including oral administration and intravenous injection. The challenges associated with drug permeation through layers of skin, which act as a major barrier, are explored, and strategies to overcome these limitations are discussed in detail. This review categorizes skin-mediated drug delivery methods based on the means of increasing drug permeation, and it provides a comprehensive overview of the mechanisms and techniques associated with these methods. In addition, recent advancements in the application of skin-mediated drug delivery are presented. The review also outlines the limitations of ongoing research and suggests future perspectives of studies regarding the skin-mediated delivery of drugs.

Investigating the Hydrodynamics of Intravenous Drug Infusions

One of the most common reported adverse events for intravenous (IV) infusions are infusion site reactions, ranging from redness and pain at the site of infusion to thrombophlebitis.  The connection between drug infusion and what drives these adverse events is not well understood. To aid in understanding these phenomena, it is crucial to accurately characterize the evolving hemodynamic environment of the infusion site when developing new intravenous formulations, as too rapid dilution may cause precipitation in the vein, while too little dilution might contribute to phlebitis. In this study, a Large-Eddy Simulation (LES) turbulence modeling inside a Computational Fluid Dynamics (CFD) framework has been used to simulate the flow and mixing characteristics of an infusion entering the bloodstream. This work represents the first such study reporting transient flow fields for intravenous infusions using LES CFD simulations with a realistic non-Newtonian blood model. The output of the CFD model closely resembled the flow and mixing patterns generated in benchtop tests for infusions into a blood analogue and water as the venous fluid across a wide range of flow rates.  These models were then investigated further to compare how changes to the fluid rheology model, needle orientation and needle position within the vein resulted in altered mixing regimes at different flow rates.

Fucoidan-mediated targeted delivery of dasatinib-loaded nanoparticles amplifies apoptosis and endows cytotoxic potential in triple-negative breast cancer

Dasatinib (DST) is a tyrosine kinase inhibitor with established antiproliferative activity in Triple-negative breast cancer. Conventional treatment strategies with DST have several pitfalls related to the development of resistance, lower cellular uptake and unwanted adverse effects. To address these issues, we have prepared P-selectin-targeted nanoparticles of DST with fucoidan (FUC) as a ligand. Poly lactide-co-glycolide nanoparticles of DST were coated with chitosan (CH) and FUC via electrostatic interaction (DST-CH-FUC-NPs). The mean particle size of 210.36 ± 0.66 nm and a polydispersity index of 0.234 ± 0.013 was observed for DST-CH-FUC-NPs. TEM and FTIR analysis proved CH coating followed by an FUC layer on nanoparticles. DST-CH-FUC-NPs showed a sustained release profile up to 120 h and 2.9 times less hemolytic potential than free DST suspension. DST-CH-FUC-NPs demonstrated 8-fold higher cytotoxicity compared to free DST in MDA-MB-231 cells. Rhodamine-CH-FUC- NPs showed 19 times and 3 times higher cellular uptake than free Rhodamine and Rhodamine-CH-NPs, respectively. DST-CH-FUC-NPs also displayed increased ROS production and mitochondrial membrane potential damage. Apoptosis study revealed a 7.5-fold higher apoptosis index for DST-CH-FUC-NPs than free DST. Subsequently, the DST-CH-FUC-NPs showed increased inhibition of cell migration, where approximately 5 % wound closure was noted. Further, DST-CH-FUC-NPs confirmed higher disruption of lysosomal membrane integrity, which is well correlated with apoptosis results. In addition, developed NPs were nontoxic on MCF 10 A normal cells. All these findings suggest that fabricated DST-CH-FUC-NPs are promising biocompatible carriers for tumor-targeted delivery and enhanced efficacy of dasatinib.

Fabrication of Chitosan/PEGDA Bionanocomposites for Enhanced Drug Encapsulation and Release Efficiency

Drug delivery systems (DDS) have evolved in the last decades with the development of hydrogels and particles. However, challenges such as high systemic uptake, side effects, low bioavailability, and encapsulation efficiency continue to be significant hurdles faced by such DDSs. Particles and hydrogels can be specifically designed for targeted DDSs to mitigate some of these problems. This study developed chitosan (Cs) particles (Ps) and composite films using poly(ethylene glycol) diacrylate (PEGDA) as a copolymer to encapsulate gentamicin (GtS) for drug delivery. We demonstrated that lysozyme degrades the chitosan β-1,4 glycosidic bonds to release GtS. PEGDA increased drug encapsulation efficiency by shielding the repelling forces of like charges between Cs and GtS. The data show that PEGDA does not hinder enzymatic degradation while increasing drug encapsulation efficiency and producing more homogeneous particles. Additionally, we utilized Michael's reaction to cross-link Cs, CsPs, and PEGDA to produce a film designed for drug delivery. The film is an anchor for CsPs to prevent premature drug release. The cross-linking of Cs and PEGDA does not affect lysozyme activity, and CsPs could successfully release GtS without affecting GtS activity.

Delivery of biologics: Topical administration

Biologics are unaffordable to a large majority of the global population because of prohibitively expensive fermentation systems, purification and the requirement for cold chain for storage and transportation. Limitations of current production and delivery systems of biologics were evident during the recent pandemic when <2.5% of vaccines produced were available to low-income countries and ∼19 million doses were discarded in Africa due to lack of cold-chain infrastructure. Among FDA-approved biologics since 2015, >90% are delivered using invasive methods. While oral or topical drugs are highly preferred by patients because of their affordability and convenience, only two oral drugs have been approved by FDA since 2015. A newly launched oral biologic costs only ∼3% of the average cost of injectable biologics because of the simplified regulatory approval process by elimination of prohibitively expensive fermentation, purification, cold storage/transportation. In addition, the cost of developing a new biologic injectable product (∼$2.5 billion) has been dramatically reduced through oral or topical delivery. Topical delivery has the unique advantage of targeted delivery of high concentration protein drugs, without getting diluted in circulating blood. However, only very few topical drugs have been approved by the FDA. Therefore, this review highlights recent advances in oral or topical delivery of proteins at early or advanced stages of human clinical trials using chewing gums, patches or sprays, or nucleic acid drugs directly, or in combination with, nanoparticles and offers future directions.

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.

Dual acting acid-cleavable self-assembling prodrug from hyaluronic acid and ciprofloxacin: A potential system for simultaneously targeting bacterial infections and cancer

The incidence and of bacterial infections, and resulting mortality, among cancer patients is growing dramatically, worldwide. Several therapeutics have been reported to have dual anticancer and antibacterial activity. However, there is still an urgent need to develop new drug delivery strategies to improve their clinical efficacy. Therefore, this study aimed to develop a novel acid cleavable prodrug (HA-Cip) from ciprofloxacin and hyaluronic acid to simultaneously enhance the anticancer and antibacterial properties of Cip as a superior drug delivery system. HA-Cip was synthesised and characterised (FT-IR, HR-MS, and H1 NMR). HA-Cip generated stable micelles with an average particle size, poly dispersion index (PDI) and zeta potential (ZP) of 237.89 ± 25.74 nm, 0.265 ± 0.013, and -17.82 ± 1.53 mV, respectively. HA-Cip showed ≥80 % cell viability against human embryonic kidney 293 cells (non-cancerous cells), ˂0.3 % haemolysis; and a faster pH-responsive ciprofloxacin release at pH 6.0. HA-Cip showed a 5.4-fold improvement in ciprofloxacin in vitro anticancer activity against hepatocellular cancer (HepG2) cells; and enhanced in vitro antibacterial activity against Escherichia coli and Klebsiella pneumoniae at pH 6.0. Our findings show HA-Cip as a promising prodrug for targeted delivery of ciprofloxacin to efficiently treat bacterial infections associated, and/or co-existing, with cancer.

Biomimetic pH/lipase dual responsive vitamin-based solid lipid nanoparticles for on-demand delivery of vancomycin

In this study, ascorbyl tocopherol succinate (ATS) was designed, synthesized and characterized via FT-IR, HR-MS, H¹ NMR and C¹³ NMR, to simultaneously confer biomimetic and dual responsive properties of an antibiotic nanosystem to enhance their antibacterial efficacy and reduce antimicrobial resistance. Therefore, an in silico-aided design (to mimic the natural substrate of bacterial lipase) was employed to demonstrate the binding potential of ATS to lipase (-32.93 kcal/mol binding free energy (ΔG_bind) and bacterial efflux pumps blocking potential (NorA ΔG_bind: -37.10 kcal/mol, NorB ΔG_bind: -34.46 kcal/mol). ATS bound stronger to lipase than the natural substrate (35 times lower Kd value). The vancomycin loaded solid lipid nanoparticles (VM-ATS-SLN) had a hydrodynamic diameter, zeta potential, polydispersity index and entrapment efficiency of 106.9 ± 1.4 nm, -16.5 ± 0.93 mV, 0.11 ± 0.012 and 61.9 ± 1.31%, respectively. In vitro biocompatibility studies revealed VM-ATS-SLN biosafety and non-haemolytic activity. Significant enhancement in VM release was achieved in response to acidified pH and lipase enzyme, compared to controls. VM-ATS-SLN showed enhanced sustained in vitro antibacterial activity for 5 days, 2-fold greater MRSA biofilm growth inhibition and 3.44-fold reduction in bacterial burden in skin infected mice model compared to bare VM. Therefore, ATS shows potential as a novel multifunctional adjuvant for effective and targeted delivery of antibiotics.

Novel Design of Peripheral Infusion Catheter Improves the Kinetics of Intravenous Drug Release

Short peripheral catheters are ubiquitous in today's healthcare environment, enabling effective and direct delivery of fluids and medications intravenously. A commonly associated complication of their use is thrombophlebitis-thrombus formation-involved inflammation of the vein wall. A novel design of a very short peripheral catheter showed promising results in a pig model in reducing the mechanical irritation to the vein wall. Here, the kinetics of drug release through the novel catheter was compared to a standard commercial catheter using experimental and computational models. In a good agreement, in vitro and in silico models reveal the superiority of the novel catheter design with faster washout time, favorable spatial distribution within the vein, and substantially lower wall shear stress. We submit therefore that the novel design has an improved drug removal profile compared to the conventional catheter and can potentially reduce chemical irritation to the vein wall and minimize the risk for thrombophlebitis. CLINICAL RELEVANCE: Short peripheral catheters are ubiquitous in today's healthcare environment, allowing effective and direct delivery of fluids and medications intravenously. It is well known, however, that prolonged exposure to an irritant drug may lead to its absorption in the endothelial layer lining the vein wall, promoting among other, thrombophlebitis that may lead to increased morbidity, delayed treatment, and prolonged hospitalization. There have been multiple calls to consider low infusion rates with various infusion protocols and to place the catheter tip as central as possible to promote faster drug clearance and reduce the potential vessel damage, but the requisite device had not been available, and the short peripheral catheter is still, and for decades, the standard of care. Towards this end, we recently introduced a novel very short peripheral catheter design, and here, we demonstrate using experimental and computational models its favorable spatial and temporal drug-releasing profiles compared with the standard catheter. The clinically potential relevance is underscore both by the more efficient perfusion of IV drugs and lower irritation to the vein wall at the site of injection. Graphical abstract.

Water-soluble inhibitors of ABCG2 (BCRP) - A fragment-based and computational approach

A good balance between hydrophilicity and lipophilicity is a prerequisite for all bioactive compounds. If the hydrophilicity of a compound is low, its solubility in water will be meager. Many drug development failures have been attributed to poor aqueous solubility. ABCG2 inhibitors are especially prone to be insoluble since they have to address the extremely large and hydrophobic multidrug binding site in ABCG2. For instance, our previous, tariquidar-related ABCG2 inhibitor UR-MB108 (1) showed high potency (79 nM), but very low aqueous solubility (78 nM). To discover novel potent ABCG2 inhibitors with improved solubility we pursued a fragment-based approach. Substructures of 1 were optimized and the fragments 'enlarged' to obtain inhibitors, supported by molecular docking studies. Synthesis was achieved, i.a., via Sonogashira coupling, click chemistry and amide coupling. A kinetic solubility assay revealed that 1 and most novel inhibitors did not precipitate during the short time period of the applied biological assays. The solubility of the compounds in aqueous media at equilibrium was investigated in a thermodynamic solubility assay, where UR-Ant116 (40), UR-Ant121 (41), UR-Ant131 (48) and UR-Ant132 (49) excelled with solubilities between 1 μM and 1.5 μM - an up to 19-fold improvement compared to 1. Moreover, these novel N-phenyl-chromone-2-carboxamides inhibited ABCG2 in a Hoechst 33342 transport assay with potencies in the low three-digit nanomolar range, reversed MDR in cancer cells, were non-toxic and proved stable in blood plasma. All properties make them attractive candidates for in vitro assays requiring long-term incubation and in vivo studies, both needing sufficient solubility at equilibrium. 41 and 49 were highly ABCG2-selective, a precondition for developing PET tracers. The triple ABCB1/C1/G2 inhibitor 40 qualifies for potential therapeutic applications, given the concerted role of the three transporter subtypes at many tissue barriers, e.g. the BBB.

A self-assembled polymer therapeutic for simultaneously enhancing solubility and antimicrobial activity and lowering serum albumin binding of fusidic acid

The global antimicrobial resistance crisis has prompted worldwide efforts to develop new and more efficient antimicrobial compounds, as well as to develop new drug delivery strategies and targeting mechanisms. This study aimed to synthesize a novel polyethylene glycol-fusidic acid (PEG-FA) conjugate for self-assembly into nano-sized structures and explore its potential for simultaneously enhancing aqueous solubility and antibacterial activity of FA. In addition, the ability of PEG-FA to bind to HSA with lower affinity than FA is also investigated. Haemolysis and in vitro cytotoxicity studies confirmed superior biosafety of the novel PEG-FA compared to FA. The water solubility of FA after PEG conjugation was increased by 25-fold compared to the bare drug. PEG-FA nanoparticles displayed particle size, polydispersity index and zeta potential of 149.3 ± 0.21 nm, 0.267 ± 0.01 and 5.97 ± 1.03 mV, respectively. Morphology studies using high-resolution transmission electron microscope revealed a homogenous spherical shape of the PEG-FA nanoparticles. In silico studies showed that Van der Waals forces facilitated PEG-FA self-assembly. HSA binding studies showed that PEG-FA had very weak or no interaction with HSA using in silico molecular docking (-2.93 kcal/mol) and microscale thermophoresis (K_d=14999 ± 1.36 µM), which may prevent bilirubin displacement. Conjugation with PEG did not inhibit the antibacterial activity of FA but rather enhanced it by 2.5-fold against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus, compared to the bare FA. These results show that PEG-FA can simultaneously enhance solubility and antibacterial activity of FA, whilst also reducing binding of HSA to decrease its side effects.

Supramolecular self-assembled drug delivery system (SADDs) of vancomycin and tocopherol succinate as an antibacterial agent: in vitro, in silico and in vivo evaluations

In this study self-assembled drug delivery system (SADDs) composed of a hydrophobic d-α-tocopherol succinate (TS) and a hydrophilic vancomycin (VCM) were formulated, and its potential for enhancing the antibacterial activity of VCM against Staphylococcus aureus (SA) and Methicillin-resistant Staphylococcus aureus (MRSA) were explored. The SADDs were synthesized via supramolecular complexation, then characterized for in silico, in vitro and in vivo studies. In silico studies confirmed the self-assembly of VCM/TS into NPs. The size, surface charge and drug loading of the SADDs was ˂100 nm, -27 mV and 68%, respectively. The SADDs were non-hemolytic and biosafe. A sustained release of VCM from SADDs was noted, with 52.2% release after 48 hr. The in vitro antibacterial test showed a twofold decrease in Minimum inhibitory concentration (MIC) against SA and MRSA, and a significantly higher reduction in MRSA biofilms compared to bare VCM. Further, in silico studies confirmed strong and stable binding of TS to MRSA efflux pumps. The in vivo study using mice skin infection models showed a 9.5-fold reduction in bacterial load after treatment with SADDs, in comparison with bare VCM. These findings affirmed that VCM/TS NPs as a promising novel nano-delivery for treating bacterial infections.

Phlebitis in Intravenous Amiodarone Administration: Incidence and Contributing Factors

BACKGROUND

Intravenous amiodarone is the gold-standard treatment for arrhythmias, but phlebitis is a common adverse effect.

OBJECTIVES

To determine the incidence and contributing factors of amiodarone-induced phlebitis and examine phlebitis severity.

METHODS

A systematic review was conducted of articles published before February 2016 in the Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, MEDLINE, Embase, Web of Science, and gray databases (Bielefeld, Lenus, EUGrey, RIAN, and DART). All studies in which amiodarone-induced phlebitis was a primary or secondary outcome were included. Meta-analysis was not appropriate because of study heterogeneity. Studies of the same contributing factors were analyzed together.

RESULTS

In the 20 included studies, phlebitis incidence ranged from 0% to 85%. Increasing the infusion concentration from 1.2 mg/mL to 1.8 mg/mL increased the phlebitis rate (P < .001). Total amiodarone doses greater than 1 g resulted in higher phlebitis rates than did doses less than 0.45 mg (P < .001). Most infusion durations and rates were not correlated with phlebitis incidence. However, phlebitis incidence was lower with bolus administration than with longer infusions (P = .002). The use of in-line filters and nursing guidelines significantly reduced phlebitis rates (P < .001) and phlebitis severity. The most common phlebitis severity grades, in descending order, were 0, 1, 2, 3, and 4.

CONCLUSIONS

Understanding factors that increase the risk of amiodarone-induced phlebitis can guide better practice. In-line filters and nursing guidelines should always be implemented when administering intravenous amiodarone. Increased surveillance is required when higher dosages and concentrations are used.

Design and development of microemulsion systems of a new antineoplaston A10 analog for enhanced intravenous antitumor activity: In vitro characterization, molecular docking, 125I-radiolabeling and in vivo biodistribution studies

A10, (3-phenylacetylamino-2,6-piperidinedione), is a natural peptide with broad antineoplastic activity. Recently, in vitro antitumor effect of a new A10 analog [3-(4-methoxybenzoylamino)-2,6-piperidinedione] (MPD) has been verified. However, poor aqueous solubility represents an obstacle towards intravenous formulation of MPD and impedes successful in vivo antitumor activity. To surmount such limitation, MPD microemulsion (MPDME) was developed. A 3¹2² full factorial design using Design-Expert® software was adopted to study the influence of different parameters and select the optimum formulation (MPDME1). Transmission electron microscopy (TEM) displayed spherical droplets of MPDME1. The cytotoxicity of MPDME1 in Michigan Cancer Foundation 7 (MCF-7) breast cancer cell line exceeded that of MPD solution (MPDS) and tamoxifen. Compatibility with injectable diluents, in vitro hemolytic studies and in vivo histopathological examination confirmed the safety of parenteral application of MPDME1. Molecular docking results showed almost same binding affinity of A10, MPD and ¹²⁵I-MPD with histone deacetylase 8 (HDAC8) receptor. Accordingly, radioiodination of MPDME1 and MPDS was done via direct electrophilic substitution reaction. Biodistribution of ¹²⁵I-MPDME1 and ¹²⁵I-MPDS in normal and tumor (ascites and solid) bearing mice showed high accumulation of ¹²⁵I-MPDME1 in tumor tissues. Overall, the results proved that MPDME represents promising parenteral delivery system capable of improving antineoplastic activity of MPD.

Development and evaluation of camptothecin loaded polymer stabilized nanoemulsion: Targeting potential in 4T1-breast tumour xenograft model

Targeted delivery of anticancer agents is poised to improve cancer therapy, for which polymers can serve as targeting ligands or nanocarriers for chemotherapeutic agents. In this study, we have developed and evaluated the efficacy of a camptothecin (CPT)-loaded polymer stabilized nanoemulsion (PSNE) for the passive targeted delivery to breast cancer. Based on the pseudo-ternary phase diagrams, PSNEs were developed using capmul MCM:poloxamer 407 (4:1), solutol HS 15:simulsol P23 (1:2) and water. CPT polymer mixture was developed by solvent evaporation technique. The PSNEs were characterized for droplet size distribution, plasma protein adsorption, drug release, in-vivo targeting potential, hemolytic potential, cytotoxicity, genotoxicity, in-vivo biodistribution and CPT lactone ring stability. The developed PSNEs showed uniform droplet distribution, extended drug release (76.59±6.12% at 24h), acceptable hemolytic potential, significant cytotoxicity (IC₅₀=176±4.3ng/mL) and genotoxicity against MCF-7 cancer cells but low DNA damage potential in human peripheral blood lymphocytes. The efficiency of PSNEs for the targeted delivery of CPT into the tumour regions was documented in 4T1-breast tumour xenografted BALB/c mice. In-vivo biodistribution study shows that 7105.84±568.46ng/g of CPT was passively targeted from PSNE to breast cancer tissue. About 80% of the lactone form was stable for 24h. Taken together, our study provides a promising strategy for developing PSNE-targeted drug delivery system for the breast cancer therapy.

Microparticles and Nanoparticles Delivered in Intravenous Saline and in an Intravenous Solution of a Therapeutic Antibody Product

Intravenous (IV) infusion is used for administration of a large proportion of biologic therapeutics, including most monoclonal antibody products. In this study, we determined the subvisible particle levels in IV solutions and after the solutions were processed with an IV administration setup that mimicked the typical clinical method of administration. IV saline in bags manufactured by both Hospira and Baxter contained 1600-8000 microparticles/mL and 4-73 × 10⁶ nanoparticles/mL in solution. When IV immunoglobulin was diluted into the IV saline, 3700-23,000 microparticles/mL and 18-240 × 10⁶ nanoparticles/mL were detected. During processing of the solution through the IV system, in-line filters removed most microparticles. However, there were still 1-21 × 10⁶ nanoparticles/mL in IV saline and 7-83 × 10⁶ nanoparticles/mL in IV immunoglobulin diluted in saline. Finally, in samples processed through in-line filters, we found relatively large microparticles (20-60 μm) that were composed of protein or polycarbonate. These particles resulted from shedding of polycarbonate and sloughing off of protein films downstream from the filter membrane. Overall, the results document that even with in-line filters in place, high levels of subvisible particles are delivered to patients and there is a need for improved, more effective filters and IV solutions with lower particle levels.

Compatibility and stability of the novel anti-cancer agent C1311 in infusion devices and its in vitro biocompatibility

C1311 is the lead compound from the imidazoacridinones, a novel group of rationally designed anti-cancer agents. The compound is pharmaceutically formulated as a lyophilized product containing 100 mg C1311 (anhydrous free base) per dosage unit and requires reconstitution before intravenous administration. The aim of this study was to determine the stability of C1311 in the reconstituted solution and infusion solution and its compatibility with infusion devices. Moreover, the buffer capacity and haemolytic potential of C1311 infusion solutions, which exhibit a relatively low pH of 2-3, were evaluated in vitro. C1311 was shown to be stable in the reconstituted solution for at least 48 h and for at least 96 h after subsequent dilution in 0.9% sodium chloride and 5% dextrose. In vitro infusion simulation studies showed C1311 infusion solutions to be compatible with a low-density polyethylene administration set. Furthermore, the buffer capacity and haemolysis studies showed no indications for haemolysis or potential for vascular irritation upon continuous infusion of C1311. In conclusion, C1311 lyophilized product is adequately stable and compatible after reconstitution and in infusion fluids to be used in the clinic and is not expected to cause formulation-associated side effects in the intended administration schedule in the forthcoming Phase I clinical study.

The influence of non-ionisable excipients on precipitation parameters measured using the CheqSol method

OBJECTIVES

The aim of this study was to determine the influence of non-ionisable excipients hydroxypropyl-β-cyclodextrin (HPβCD) and poloxamers 407 and 188 on the supersaturation and precipitation kinetics of ibuprofen, gliclazide, propranolol and atenolol induced through solution pH shifts using the CheqSol method.

METHODS

The drug's kinetic and intrinsic aqueous solubilities were measured in the presence of increasing excipient concentrations using the CheqSol method. Experimental data rate of change of pH with time was also examined to determine excipient-induced parachute effects and influence on precipitation rates.

KEY FINDINGS

The measured kinetic and intrinsic solubilities provide a determination of the influence of each excipient on supersaturation index, and the area under the CheqSol curve can measure the parachute capability of excipients. The excipients influence on precipitation kinetics can be measured with novel parameters; for example, the precipitation pH or percentage ionised drug at the precipitation point, which provide further information on the excipient-induced changes in precipitation performance.

CONCLUSION

This method can therefore be employed to measure the influence of non-ionisable excipients on the kinetic solubility behaviour of supersaturated solutions of ionisable drugs and to provide data, which discriminates between excipient systems during precipitation.

HPLC Investigated Physicochemical Compatibility between Artrosilene® Injectable Solution and other Pharmaceutical Products Frequently Used for Combined Therapy into Elastomeric Baxter LV5 Infusion Devices

Ketoprofen lysine salt (Artrosilene®, injectable solution) is a non-steroidal anti-inflammatory agent frequently administered by slow intravenous infusion with portable elastomeric infusion systems in association regimen with other analgesic drugs. The aim of this study was to investigate the physicochemical compatibility between ketoprofen lysine salt (Artrosilene®, injectable solution) and other injectable drugs frequently used in association, such as tramadol hydrochloride, keterolac tromethamine and morphine hydrochloride, into the Infusor LV5, Baxter elastomeric infusion system. Physicochemical properties of drug mixture, including colour, clarity, pH and drug content were observed or measured by a reversed-phase HPLC method with UV detection, before and after (up to 7 days) mixing at room temperature and under light protection. The results obtained demonstrated the physicochemical compatibility of ketoprofen lysine salt (Artrosilene®, injectable solution) with all drug formulations at every tested mixing ratios into Baxer Infusor LV5 infusion devices.

Subtilisin QK-2: secretory expression in Lactococcus lactis and surface display onto gram-positive enhancer matrix (GEM) particles

Background

Purified from the supernatant of Bacillus subtilis QK02 culture broth, Subtilisin QK-2 is a type of effective thrombolytic reagent that has great exploitable potential. However, the unbearable flavor that occurs with fermentation and the complicated methods that are required to obtain pure products limit the application of this enzyme. Lactic acid bacteria (LAB)-based delivery vehicles are promising as cheap and safe options for medicinal compounds. The secretory expression and surface display using LAB may popularize Subtilisin QK-2 more easily and conveniently with minimal adverse effects.

Results

Subtilisin QK-2 was expressed successfully in two forms using lactic acid bacteria. For the secretory expression in Lactococcus lactis, Subtilisin QK-2 was efficiently secreted into the culture using the promoter P_nisA and signal peptide SP_Usp. The expression levels were not different in L. lactis NZ9000 and NZ3900 without the effect of different selection markers. However, leaky expression was only detected in L. lactis NZ3900. The biological activity of this secreted Subtilisin QK-2 was enhanced by modulating the pH of medium to slightly alkaline during induction and by codon optimization of either the entire gene sequence (qk′) or only the propeptide gene sequence (qkpro′). For surface display onto gram-positive enhancer matrix (GEM) particles, n LysM repeats from the C-terminal region of the major autolysin AcmA of L. lactis were fused to either the C-terminus (n = 1, 3, 5) or the N-terminus (n = 1) of the Subtilisin QK-2. These fusion proteins were secreted into the culture medium, and the QK-3LysM was able to bind to the surface of various LAB GEM particles without a loss of fibrinolytic activity. Furthermore, the binding capacity significantly increased with a higher concentration of QK-3LysM. Compared to the free-form Subtilisin QK-2, the QK-3LysM displayed on the surface of GEM particles was more stable in the simulated gastric juice.

Conclusions

Combined with the safety and popularity of LAB, Subtilisin QK-2 may be easily applied worldwide to prevent and control thrombosis diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s12934-016-0478-7) contains supplementary material, which is available to authorized users.

Phosphonooxymethyl Prodrug of Triptolide: Synthesis, Physicochemical Characterization, and Efficacy in Human Colon Adenocarcinoma and Ovarian Cancer Xenografts

A disodium phosphonooxymethyl prodrug of the antitumor agent triptolide was prepared from the natural product in three steps (39% yield) and displayed excellent aqueous solubility at pH 7.4 (61 mg/mL) compared to the natural product (17 μg/mL). The estimated shelf life (t₉₀) for hydrolysis of the prodrug at 4 °C and pH 7.4 was found to be two years. In a mouse model of human colon adenocarcinoma (HT-29), the prodrug administered intraperitoneally was effective in reducing or eliminating xenograft tumors at dose levels as low as 0.3 mg/kg when given daily and at 0.9 mg/kg when given less frequently. When given via intraperitoneal and oral routes at daily doses of 0.6 and 0.9 mg/kg, the prodrug was also effective and well tolerated in a mouse model of human ovarian cancer (A2780).

Comparison of the endothelial toxicity induced by short-term amiodarone and diazepam exposure in a human umbilical vein endothelial cell line (EVC304)

CONTEXT

Venous irritation is the most common side effect of intravenous therapy. Although many in vitro models have been developed to evaluate intravenous drug irritation, these models are not widely accepted.

OBJECTIVES

The aim of this paper is to determine whether delayed or immediate cytotoxicity better reflects the in vivo venous irritation ranking.

MATERIALS AND METHODS

We compared the endothelial toxicity induced by high-concentrations of amiodarone and diazepam after short-term exposure (20 min) in a human umbilical vein endothelial cell line (EVC304) by using five in vitro models: lactate dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G6PD), glutathione (GSH), adenosine triphosphate (ATP), and MTT assays.

RESULTS

In the 24-h MTT assay, the IC50 of diazepam and amiodarone was 1.08 and 1.96 mM, respectively. In the 48-h MTT assay, the IC50 of diazepam and amiodarone was 1.114 and 1.128 mM, respectively. In the intracellular LDH and G6PD assays, the EC50 of diazepam was found to be 3.307 and 1.53 mM, while the values of amiodarone were 0.853 and 0.325 mM, respectively. In the intracellular ATP and GSH assays, the EC50 of diazepam was 0.905 and 1.283 mM, while the values of amiodarone were 0.040 and 0.326 mM, respectively.

CONCLUSION

Both the results of intracellular macromolecule activities and micromolecule concentrations were similar to that observed in in vivo venous irritation studies. However, the delayed cytotoxicity rank from the MTT assay is inconsistent with the in vivo venous irritation rank, suggesting that initial toxicity, but not the delayed toxicity, is related to venous irritation.

An improved method to prepare an injectable microemulsion of the galanin-receptor 3 selective antagonist, SNAP 37889, using Kolliphor(®) HS 15

Research into the galanin-3 (GAL3) receptor has many challenges, including the lack of commercially available selective ligands. While the identification of non-peptidergic GAL3 receptor-selective antagonists, 1-phenyl-3-[3-(trifluoromethyl)phenyl]iminoindol-2-one (SNAP 37889) and 1-[3-(2-pyrrolidin-1-ylethoxy)phenyl]-3-[3-(trifluoromethyl)phenyl]iminoindol-2-one (SNAP 398299) have implicated a role for GAL3 receptors in anxiety, depression and drug-seeking behaviour, a major limitation of their use is poor aqueous solubility. Previously we have used 5% dimethylsulfoxide (DMSO) with 1% hydroxypropylmethyl cellulose in saline to dissolve SNAP 37889 for intraperitoneal (i.p.) injections of rats; however this produced a micro-suspension that was not ideal. The injectable formulation of SNAP 37889 was improved as follows:•30% (w/v) Kolliphor(®) HS 15 (Solutol HS(®) 15) and sodium phosphate buffer (0.01 M, pH 7.4) were used as vehicles.•A smooth glass mortar and pestle was used to triturate the Kolliphor(®) HS 15 and SNAP 37889 into a paste before addition to the sodium phosphate buffer at room temperature (RT).•The resulting mixture was vortexed until the paste was fully dissolved and the microemulsion was allowed to sit for 20 min to allow air bubbles to coalesce.

Effect of the excipient concentration on the pharmacokinetics of PM181104, a novel antimicrobial thiazolyl cyclic peptide antibiotic, following intravenous administration to mice

Thiazolyl cyclic peptide antibiotics are known for their poor aqueous solubility and unfavorable pharmacokinetics (PK) and hence pose challenging tasks in developing these antibiotics as clinical candidates. In the current paper, we report a possible way to address these challenges with exemplification of our antibiotic PM181104. The approach was to prepare formulations with known excipients, Polysorbate 80 (Tween 80, T-80) and PEG 400 through their varied stiochiometric combination in appropriate ratio to achieve acceptable osmolarity, pH and particle size of the formulation. Two different sets of formulations were prepared with two distinct average particle diameters ranging from 32.8 to 465.4 nm. First, semi-transparent solutions with a particle size of >100 nm were achieved by keeping concentration of PEG 400 constant at 8% (w/v) and decreasing the amounts of T-80. Second, clear colorless solutions with a particle size of <100 nm were achieved by keeping concentration of T-80 constant at 8% (w/v) and decreasing the amounts of PEG 400. In PK studies, intravenous administration of formulation with particle size <100 nm to mice resulted in a two-fold increase in area under the plasma concentration-time curve (AUC_last) and concentration at time zero (C₀), there by facilitating the selection of suitable formulation for further efficacy studies.

Development and evaluation of magnetic microemulsion: tool for targeted delivery of camptothecin to BALB/c mice-bearing breast cancer

PURPOSE

Development and evaluation of camptothecin-loaded-microemulsion (ME) and -magnetic microemulsion (MME) for passive/active-targeted delivery to BALB/c mice-bearing breast cancer.

METHODS

Based on the pseudo-ternary phase diagrams camptothecin-loaded-MEs and -MMEs were developed using benzyl alcohol:Captex 300 (3:1), TPGS:Tween 80 (2:1) and water. Furthermore, characterized for their droplet size distribution, magnetic susceptibility and effect of droplet size in plasma and evaluated for in vitro and in vivo targeting potential, drug release, haemolytic potential, cytotoxicity, genotoxicity, in vivo biodistribution and lactone ring stability.

RESULTS

Drug-loaded MEs showed uniform droplet distribution, extended drug release (76.07 ± 4.30% at 24 h), acceptable level of haemolytic activity (<20%), significant cytotoxicity (129 ± 3.9 ng/mL) against MCF-7 cancer cells and low DNA damage in lymphocytes. Targeting potential of MMEs was documented in 4T1 breast cancer-induced BALB/c mice. MMEs were concentrated more at the target tissue on introduction of external magnetic field. In vivo biodistribution study documented the active targeting of 5067.56 ± 354.72 ng/gm and passive targeting of 1677.58 ± 134.20 ng/gm camptothecin to breast cancer from MME and ME, respectively. Lactone stability study shows around 80% of the lactone stable at 24 h.

CONCLUSIONS

Developed ME and MME may act as a promising nanocarrier for efficient targeting of breast cancer tissues.

Physicochemical characterization of asulacrine towards the development of an anticancer liposomal formulation via active drug loading: stability, solubility, lipophilicity and ionization

To facilitate the development of a liposomal formulation for cancer therapy, the physicochemical properties of asulacrine (ASL), an anticancer drug candidate, were characterized. Nano-liposomes were prepared by thin-film hydration in conjugation with active drug loading using ammonium sulphate and post-insertion with Poloxamer 188. A stability-indicating HPLC assay with diode array detection was developed for the determination of ASL concentrations. The U-shaped pH-solubility profile in aqueous solutions, with a lowest solubility at pH 7.4 (0.843 μg/mL), indicated that ASL is an ampholyte, and dilution or neutralization of acidic drug solutions used in clinical trials with physiological fluids may cause drug precipitation. The basic pKa value measured by absorbance spectroscopy was 6.72. The logD value at pH 3.8 was 1.15 which increased to 3.24 as pH increased to 7.4. ASL was found to be the most stable in acidic conditions and degraded most rapidly in alkaline conditions. An extra-liposomal pH of 5.6 during drug loading was found to be optimal to achieve the highest drug loading (DL) of 4.76% and entrapment efficiency (EE) of 99.9%. At this pH, >90% of ASL was ionized conferring high drug solubility (1mg/mL) and acted as a reservoir of unionized ASL to be transported into liposomal cores. As a suspension the optimized liposomes showed great physicochemical stability for five months at 4°C. In summary, the obtained physicochemical parameters provided insightful information useful to maximise DL into the liposomes, and explain a tendency of drug precipitation of pH-solubilized formulations following intravenous infusion.

Intravenous Pharmacokinetics, Local Tolerability, and Hemolysis of an SBE7-β-Cyclodextrin Formulation of the Neurokinin-1 Receptor Antagonist Vestipitant

Vestipitant is a potent and selective neurokinin 1 (NK-1) receptor antagonist that was investigated as a potential treatment for post-operative nausea and vomiting (PONV). A previous mannitol-based formulation of vestipitant was associated with hemolytic activity in preclinical studies. In an effort to reduce the hemolytic potential and develop an IV formulation of vestipitant that could be administered more rapidly, an IV formulation containing sulfobutylether-7-beta-cyclodextrin (SBE7-β-CD, Captisol™) was developed and tested in a phase 1 clinical study. This was a randomized, single-blind (subjects and investigator—blinded, sponsor-unblinded), placebo controlled, dose escalation study in healthy subjects in which 7 cohorts of 8 subjects per cohort received SBE7-β-CD -based vestipitant (2 mg/mL) or placebo (saline) in a 3:1 ratio (active:placebo) at different doses and infusion rates. The results demonstrated the ability to infuse up to 48 mg vestipitant in a 2 mg/mL formulation over 30 seconds with no evidence of hemolytic effects. Cohorts of subjects at lower doses and longer infusion duration (>1 minute) reported more AEs related to the infusion site than those at the higher doses and faster infusion rates.

Bexarotene nanocrystal-Oral and parenteral formulation development, characterization and pharmacokinetic evaluation

Bexarotene (Targretin®) is a synthetic retinoid that selectively activates the retinoid X receptor subfamily of retinoid receptors and exhibits potent anti-tumor activity. However, the poor solubility and bioavailability limit its application. The main aim of this study is to investigate the potential of oral and parenteral nanocrystals in enhancing the bioavailability of bexarotene. In this work, the orthogonal design was used to screen the optimum stabilizers and precipitation-combined microfluidization method was employed to obtain the optimal nanocrystals. According to DSC, X-ray diffraction analysis and Raman examination, the nanocrystals were still in crystalline state after the preparation procedure. By reducing the particle size, the in vitro dissolution rate of bexarotene was increased significantly. The in vivo test was carried out in rats and pharmacokinetic parameters of the bexarotene solution and bexarotene nanocrystals were compared after gavage and intravenous administration. The higher AUC and lower Cmax indicated that oral bexarotene nanocrystals significantly increased the bioavailability of bexarotene and decreased its side effects. Compared to the oral nanocrystals, the intravenous nanocrystals cut losses and increased bioavailability because of the absence of first pass effect and enterohepatic circulation.

Innovative pharmaceutical development based on unique properties of nanoscale delivery formulation

The advent of nanotechnology has reignited interest in the field of pharmaceutical science for the development of nanomedicine. Nanomedicinal formulations are nanometer-sized carrier materials designed for increasing the drug tissue bioavailability, thereby improving the treatment of systemically applied chemotherapeutic drugs. Nanomedicine is a new approach to deliver the pharmaceuticals through different routes of administration with safer and more effective therapies compared to conventional methods. To date, various kinds of nanomaterials have been developed over the years to make delivery systems more effective for the treatment of various diseases. Even though nanomaterials have significant advantages due to their unique nanoscale properties, there are still significant challenges in the improvement and development of nanoformulations with composites and other materials. Here in this review, we highlight the nanomedicinal formulations aiming to improve the balance between the efficacy and the toxicity of therapeutic interventions through different routes of administration and how to design nanomedicine for safer and more effective ways to improve the treatment quality. We also emphasize the environmental and health prospects of nanomaterials for human health care.

Strategies to address low drug solubility in discovery and development

Drugs with low water solubility are predisposed to low and variable oral bioavailability and, therefore, to variability in clinical response. Despite significant efforts to "design in" acceptable developability properties (including aqueous solubility) during lead optimization, approximately 40% of currently marketed compounds and most current drug development candidates remain poorly water-soluble. The fact that so many drug candidates of this type are advanced into development and clinical assessment is testament to an increasingly sophisticated understanding of the approaches that can be taken to promote apparent solubility in the gastrointestinal tract and to support drug exposure after oral administration. Here we provide a detailed commentary on the major challenges to the progression of a poorly water-soluble lead or development candidate and review the approaches and strategies that can be taken to facilitate compound progression. In particular, we address the fundamental principles that underpin the use of strategies, including pH adjustment and salt-form selection, polymorphs, cocrystals, cosolvents, surfactants, cyclodextrins, particle size reduction, amorphous solid dispersions, and lipid-based formulations. In each case, the theoretical basis for utility is described along with a detailed review of recent advances in the field. The article provides an integrated and contemporary discussion of current approaches to solubility and dissolution enhancement but has been deliberately structured as a series of stand-alone sections to allow also directed access to a specific technology (e.g., solid dispersions, lipid-based formulations, or salt forms) where required.

Interaction between Zwitterionic Surfactants and Amphiphilic Drug: A Tensiometric Study

The physicochemical properties, viz, critical micelle concentration (cmc), surface excess concentration (Γ max), minimum area per head group (A min) of zwitterionic surfactants (designated as n(−)-2-m(+); n = 8, 10, 12 and m = 12, 14, 16) and their mixtures with amphiphilic antidepressant drug amitriptyline hydrochloride (AMT) were determined by using surface tension measurements. The cmc and ideal cmc (cmcid) values along with interaction parameters, β m and β σ (calculated using Rubingh's and Rosen's models), suggest attractive interactions among the components. The Krafft temperature measurements also indicate strong attractive interactions. Γ max (or A min) increases (or decreases) with the addition of gemini surfactant; the values being closer to that of the drug. These values and micellar mole fraction (X1 m-calculated from Rubingh's model and X 1 Moto-calculated from Motomura's model) indicate larger contribution of gemini surfactants in mixed micelles and smaller contribution at air/solution interface (as mole fraction values at interface, X 1 σ , are slightly smaller than X 1 m). The standard Gibbs energy of micellization (Δ G micº) and adsorption (Δ G adº) as well as excess energy of mixing (Δ G ex m) are all negative. All these results suggest higher stability of the mixed systems. UV absorbance results also suggest that the mixed micelles are stable for several days.

Nanosizing for oral and parenteral drug delivery: a perspective on formulating poorly-water soluble compounds using wet media milling technology

A significant percentage of active pharmaceutical ingredients identified through discovery screening programs is poorly soluble in water. These molecules are often difficult to formulate using conventional approaches and are associated with innumerable formulation-related performance issues, e.g. poor bioavailability, lack of dose proportionality, slow onset of action and other attributes leading to poor patient compliance. In addition, for parenteral products, these molecules are generally administered with co-solvents and thus have many undesirable side effects. Wet media milling is one of the leading particle size reduction approaches that have been successfully used to formulate these problematic compounds. The approach is a water-based media milling process where micron-sized drug particles are shear-fractured into nanometer-sized particles. Nanoparticle dispersions are stable and typically have a mean diameter of less than 200 nm with 90% of the particles being less than 400 nm. The formulation consists only of water, drug and one or more GRAS excipients. Drug concentrations approaching 300-400mg/g can be targeted with the use of minimal amounts stabilizer. Typically, on average, the drug to stabilizer ratio on a weight basis ranges from 2:1 to 20:1. These liquid nanodispersions exhibit acceptable shelf-life and can be post-processed into various types of solid dosage forms. Nanoparticulate-based drug products have been shown to improve bioavailability and enhance drug exposure for oral and parenteral dosage forms. Suitable formulations for the most commonly used routes of administration can be identified with milligram quantities of drug substance providing the discovery scientist an alternate avenue for screening and identifying superior leads. In the last few years, formulating poorly water soluble compounds as nanosuspensions has evolved from a conception to a realization. The versatility and applicability of this drug delivery platform are just beginning to be realized.

Behavior of acetyl-L-carnitine injections (Nicetile fiale) with different drugs used for combined therapy

INTRODUCTION

Acetyl-L-carnitine (Nicetile fiale; Biofutura Pharma S.p.A., Sigma Tau group, Milano, Italy) is a compound widely used for the treatment of many diseases, such as neuropathies, diabetic polyneuropathy, and Parkinson's disease. It is frequently administered via the intramuscular route with other drugs, such as steroidal anti.inflammatories, muscle relaxants, and vitamins.

METHODS

In the present study the behavior of acetyl-L-carnitine injections (Nicetile fiale) with different drugs used for combined therapy was studied. Physicochemical properties including color, clarity, pH, and drug content were observed before and after mixing at room temperature.

RESULTS

The content of all the active drugs after mixing remained optimal within 10% of their nominal values.

CONCLUSIONS

The measurements demonstrate the physicochemical compatibility between Nicetile fiale and the other tested products, meaning that there is no evidence of interactions and degradation.