Reported Severe Hypersensitivity Reactions after Intravenous Iron Administration in the European Economic Area (EEA) Before and After Implementation of Risk Minimization Measures

INTRODUCTION

Severe hypersensitivity reactions (HSRs) such as anaphylaxis are of great clinical concern because of their life-threatening potential. The adverse events attributable to intravenous iron products include HSRs. An investigation by the European Medicines Agency presented in late 2013 resulted in the implementation of risk minimization measures (RMMs).

OBJECTIVE

This study evaluated the number of severe HSRs reported for intravenous iron substances related to exposure for the 4-year periods before and after this implementation.

METHODS

This was a retrospective pharmacoepidemiologic study with a case-population design. We obtained information from the safety surveillance database EudraVigilance on spontaneously reported severe HSRs using the Medical Dictionary for Regulatory Activities preferred terms "anaphylactic reaction/shock" and "anaphylactoid reaction/shock". Exposure was estimated using IQVIA MIDAS sales data in European economic area countries.

RESULTS

Reporting rates for individual products were heterogenous, and the implementation of RMMs appeared to have no clear impact. Reporting rates remained low for the full study period for iron sucrose (0.03-0.20) and ferric gluconate (0.02-0.14) and were higher at the beginning and lower at the end of the study period for ferric carboxymaltose (1.47-0.18). No clear trend was detected for iron dextran (range 0.22-2.80) and iron (III) isomaltoside 1000 (range 0-7.94).

CONCLUSIONS

Future research is needed to investigate whether the wide variability in reporting rates for severe HSRs associated with these intravenous iron products are due to potential differences in the safety profiles of these substances.

Optofluidic detection setup for multi-parametric analysis of microbiological samples in droplets

High-throughput microbiological experimentation using droplet microfluidics is limited due to the complexity and restricted versatility of the available detection techniques. Current detection setups are bulky, complicated, expensive, and require tedious optical alignment procedures while still mostly limited to fluorescence. In this work, we demonstrate an optofluidic detection setup for multi-parametric analyses of droplet samples by easily integrating micro-lenses and embedding optical fibers for guiding light in and out of the microfluidic chip. The optofluidic setup was validated for detection of absorbance, fluorescence, and scattered light. The developed platform was used for simultaneous detection of multiple parameters in different microbiological applications like cell density determination, growth kinetics, and antibiotic inhibition assays. Combining the high-throughput potential of droplet microfluidics with the ease, flexibility, and simplicity of optical fibers results in a powerful platform for microbiological experiments.

Evaluation of the Reported Rates of Severe Hypersensitivity Reactions Associated with Ferric Carboxymaltose and Iron (III) Isomaltoside 1000 in Europe Based on Data from EudraVigilance and VigiBase™ between 2014 and 2017

Introduction

Hypersensitivity reactions (HSRs) are among the known adverse events of intravenous (i.v.) iron products. Of these, particularly severe HSRs such as anaphylaxis are of great clinical concern due to their life-threatening potential.

Methods

This was a retrospective pharmacoepidemiological study with a case-population design evaluating the number of reported severe HSRs following administration of the two i.v. iron products—ferric carboxymaltose and iron (III) isomaltoside 1000—in relation to exposure in European countries from January 2014 to December 2017. Exposure to both products was estimated using IQVIA MIDAS sales data in European countries. Information on spontaneously reported severe HSRs was obtained from and analysed separately for the two established safety surveillance databases EudraVigilance and VigiBase™ using the MedDRA^® Preferred Terms anaphylactic reaction, anaphylactic shock, anaphylactoid reaction and anaphylactoid shock associated with administration of either product.

Results

Between 2014 and 2017, the reporting rate of severe HSRs per 100,000 defined daily doses (100 mg dose equivalents of iron) varied from 0.3 to 0.5 for ferric carboxymaltose and from 2.4 to 5.0 for iron (III) isomaltoside 1000. The reporting rate ratio for iron (III) isomaltoside 1000 versus ferric carboxymaltose was between 5.6 (95% CI 3.5–9.0) and 16.2 (95% CI 9.4–27.8).

Conclusions

Findings suggest that iron (III) isomaltoside 1000 is associated with a higher reporting rate of severe HSRs related to estimated exposure than ferric carboxymaltose in European countries. Future research investigating the occurrence of severe HSRs associated with i.v. ferric carboxymaltose and iron (III) isomaltoside 1000 is needed to broaden the evidence for benefit-risk assessment.

Inhibition of human hepatitis B virus (HBV) by a novel non-nucleosidic compound in a transgenic mouse model

BAY 41-4109 is a member of a class of heteroaryl-pyrimidines that was recently identified as potent inhibitors of human hepatitis B virus (HBV) replication. We have investigated the antiviral activity of BAY 41-4109 (methyl (R)-4-(2-chloro-4-fluorophenyl)-2-(3,5-difluoro-2-pyridinyl)-6-methyl-1,4-dihydro-pyrimidine-5-carboxylate) in HBV-transgenic mice (Tg [HBV1.3 fsX(-)3'5']). Bay 41-4109 was administered per os using different schedules (b.i.d. or t.i.d. for up to 28 days) and dosages ranging from 3 to 30 mg/kg. The compound reduced viral DNA in the liver and in the plasma dose-dependently with efficacy comparable to 3TC. In contrast to 3TC-treated mice, we found a reduction of cytoplasmic hepatitis B virus core antigen (HBcAg) in liver sections of BAY 41-4109-treated mice, which indicated a different mode of action. Pharmacokinetic studies in mice have shown rapid absorption, a bioavailability of 30% and dose-proportional plasma concentrations. We conclude that BAY 41-4109 is a new anti-HBV drug candidate.

Comparison of the effects of the thrombin inhibitor r-hirudin in four animal models of neointima formation after arterial injury

Thrombin has been implicated as a contributing factor to restenosis after vessel reopening procedures. We compared the ability of the direct thrombin inhibitor recombinant (r-) hirudin to reduce neointimal growth in different animal models of arterial injury. Carotid arteries of rats, rabbits, and hypercholesterolemic minipigs were injured by withdrawal of an inflated balloon catheter. In addition, we used a double-lesion model in rabbits, which involved balloon angioplasty of a preexisting lesion induced by carotid denudation 4 weeks earlier. r-Hirudin was given in all four animal models as a short-term application (bolus of 1 mg/kg i.v. immediately before injury, followed by infusion of 1 mg.kg-1.h-1 for 2 hours, and an injection of 6 mg/kg SC). Additionally, we investigated the effects of prolonged treatment (intravenous infusion for 3 and 14 days) in rats. Inhibition of thrombin was monitored by determination of activated partial thromboplastin time, and histomorphometric analysis of the arteries was performed after 2 (rats) or 4 (rabbits and minipigs) weeks. In rabbits, short-term r-hirudin treatment reduced neointimal area by 59% (single-injury model, P = .05) and 44% (double-injury model, P = .02). In rats and minipigs no inhibition of neointimal growth was observed after short-term r-hirudin application. A 3- or 14-day infusion of r-hirudin in rats, however, resulted in 25% (P = .007) and 27% (P = .003) reductions in neointimal area, respectively. In conclusion, there is considerable interspecies variation in the time frame of susceptibility for reduction of neointimal growth by inhibition of thrombin after arterial injury. These results demonstrate the importance of testing potential antirestenotic treatments in an array of different animal models.

A 10-bp deletion in the apolipoprotein epsilon gene causing apolipoprotein E deficiency and severe type III hyperlipoproteinemia

Type III hyperlipoproteinemia (HLP) is usually associated with homozygosity for apolipoprotein (apo) E2. We identified a 30-year-old male German of Hungarian ancestry with severe type III HLP and apo E deficiency. The disease was expressed in an extreme phenotype with multiple cutaneous xanthomas. Apo E was detectable only in trace amounts in plasma but not in the different lipoprotein fractions. Direct sequencing of PCR-amplified segments of the apo epsilon gene identified a 10-bp deletion in exon 4 (bp 4037-4046 coding for amino acids 209-212 of the mature protein). The mutation is predictive for a reading frameshift introducing a premature stop codon (TGA) at amino acid 229. By western blot analysis, we found small amounts of a truncated apo E in the patient's plasma. Family analysis revealed that the proband was homozygous--and 10 of 24 relatives were heterozygous--for the mutation. Heterozygotes had, as compared to unaffected family members, significantly higher triglycerides (TG), very low-density lipoprotein (VLDL) cholesterol and a significantly higher VLDL cholesterol-to-serum TG ratio, which is indicative of a delayed remnant catabolism. We propose that the absence of a functionally active apo E is the cause of the severe type III HLP in the patient and that the mutation, even in a single dose in heterozygotes, predisposes in variable severity to the phenotypic expression of the disease.

Elevation of circulating NO: its effects on hemodynamics and vascular smooth muscle cell proliferation in rats

Object of our study was to characterize the effects of elevated circulating NO on hemodynamics and vascular smooth muscle cell proliferation in rats. Administration of molsidomine (10, 25, 50 mg/kg, bid p.o.) was followed by pharmacodynamic effects: elevation of plasma nitrite/nitrate levels and reduction of blood pressure (25 and 50 mg/kg, bid p.o.). Under these conditions no antiproliferative activity occurred in a model of "air dried" carotid artery injury. From these results we conclude that NO does not act as an antiproliferative agent under conditions where smooth muscle cell injury predominates.

Induction of c-fos expression in rat vascular smooth muscle reporter cells by selective activation of the thrombin receptor

The rat vascular smooth muscle cell (VSMC) line A10 (ATCC CRL 1476) was stably transfected with a human c-fos promoter-driven luciferase reporter gene to monitor thrombin receptor activation and subsequent induction of c-fos expression. Selective activation of the endogeneous thrombin receptor by the thrombin receptor activating peptide (TRAP1-6), SFLLRN, is shown here to result in a significant transient increase of intracellular [Ca2+], dose-dependent induction of c-fos promoter-mediated luciferase activity, and stimulation of DNA synthesis. These data demonstrate that A10 cells and reporter line derivatives thereof possess a functional thrombin receptor very similar or identical to that previously described. Results obtained with various signal transduction modulating or inhibiting agents support previous notions showing that thrombin receptor activation by SFLLRN is coupled to events involving p21ras activation, protein tyrosine kinase, and activation of PKC. The A10 reporter line described here proved to be a helpful and reliable tool to study alpha-thrombin and TRAP1-6-mediated intracellular events, since it retained most of the spectrum of biological responses found in primary VSMC cultures.

Involvement of 15-lipoxygenase in early stages of atherogenesis

The arachidonate 15-lipoxygenase which is expressed in atherosclerotic lesions is implicated in the oxidative modification of low density lipoproteins during atherogenesis. To obtain experimental in vivo evidence for this hypothesis, we analyzed the structure of oxygenated lipids isolated from the aorta of rabbits fed with a cholesterol-rich diet for different time periods and compared the pattern of oxygenation products with that isolated from low density lipoproteins treated in vitro with the pure rabbit 15-lipoxygenase and with oxygenated lipids isolated from advanced human atherosclerotic lesions. In early atherosclerotic lesions (12-wk cholesterol feeding), specific lipoxygenase products were detected whose structure was similar to those isolated from lipoxygenase-treated low density lipoproteins. The appearance of these products did coincide with the lipid deposition in the vessel wall. In later stages of atherogenesis (26-wk cholesterol feeding) the degree of oxidative modification of the tissue lipids did increase but the share of specific lipoxygenase products was significantly lower, suggesting an increasing overlay of the specific lipoxygenase products by nonenzymatic lipid peroxidation. In advanced human atherosclerotic lesions, large amounts of oxygenation products were detected whose structure suggests a nonenzymatic origin. These data suggest that the arachidonate 15-lipoxygenase is of pathophysiological importance during the early stages of atherogenesis. In later stages of plaque development nonenzymatic lipid peroxidation becomes more relevant.

Effect of protein kinase inhibitors on ACTH-stimulated aldosterone production in rat zona glomerulosa cells

In order to obtain further evidence for the involvement of protein kinases in the short-term ACTH-stimulated aldosterone synthesis in rat zona glomerulosa cells, the effects of three different compounds with protein kinase inhibitory properties were investigated. Staurosporine, H-7 and trifluoperazine inhibited ACTH-stimulated aldosterone release in a dose-dependent manner. While the inhibitory effect of H-7 was reversible upon washing of the cells with inhibitor-free medium, the inhibition was maintained in cells treated with staurosporine or trifluoperazine. In contrast to the stimulated production, basal release of aldosterone even at the highest drug concentrations tested was not completely inhibited. We thus conclude that protein kinases may play a crucial role in short-term ACTH-stimulated aldosterone production in rat glomerulosa cells.

Biosynthesis of 18-hydroxydeoxycorticosterone and corticosterone in adrenal tissue of rat strains with salt-dependent hypertension

Biosynthetic patterns of 18-OH-deoxycorticosterone (18-OH-DOC) and corticosterone (B) in adrenal tissue of Wistar-rats and two rat strains with salt-dependent hypertension (Dahl-, Sabra-rats) were measured by means of quantitative HPLC-analysis. The relative activity of 18-hydroxylation is expressed as the ratio 18-OH-DOC/18-OH-DOC + B, in the following called Q. Wistar-rats show a constant product ratio Q of 0.40 +/- 0.01. Dahl-rats, however, exhibit typical differences between the two substrains. Adrenal tissue of salt-resistant (Dahl-R) rats produces significantly less 18-OH-DOC than tissue from salt-sensitive (Dahl-S) rats: Q = 0.17 +/- 0.01 (Dahl-R) vs. Q = 0.37 +/- 0.01 (Dahl-S). No such difference was observed between the two Sabra-substrains. This indicates, that other mechanisms than an altered 11 beta-18-hydroxylation are involved in the salt-dependent hypertension of Sabra-rats.

Increased tubuloglomerular feed-back mediated suppression of glomerular filtration during acute volume expansion in rats

1. Volume expansion is currently believed to change the intrinsic properties of the juxtaglomerular apparatus such that the sensitivity of the tubuloglomerular feedback (TGF) mechanism is reduced, thus allowing glomerular filtration rate, and hence salt and water excretion, to rise. Recent studies conflict with this view and indeed the older literature reveals that the rise in glomerular filtration rate (GFR) under these conditions is far more modest than would be expected if TGF control were eliminated. 2. To investigate this problem, TGF control of filtration rate was examined by measuring single-nephron glomerular filtration rate (SNGFR) during loop of Henle perfusion at varying rates in rats under control conditions, after acute, moderate (4% of body weight), iso-oncotic volume expansion and in rats treated with antibodies to atrial natriuretic peptide (ANP) prior to the acute volume expansion. 3. With TGF control of filtration interrupted by filtrate collection from the proximal tubule, SNGFR in the expanded rats was massively increased compared with controls, although SNGFR measured in the distal tubule, and hence with TGF control intact, was only modestly increased, as was whole-kidney filtration rate. Loop perfusion at increasing rates up to 30 nl min-1 progressively decreased SNGFR in controls, and in the expanded rats the range over which control was exerted extended up to 60-80 nl min-1. For changes in loop flow around the spontaneous operating point, the sensitivity of the TGF mechanism, defined as delta SNGFR/delta loop flow, was similar in both groups. Treatment of rats with ANP antibodies prior to volume expansion substantially blunted the changes in renal salt and water excretion and the increase in SNGFR seen in the absence of loop perfusion. 4. These results are not consistent with a diminution of TGF function after volume expansion, rather with an enhancement. The latter is best accounted for by vasodilation of preglomerular resistance vessels on volume expansion, a result predicted by calculations from a model based on the serial arrangement of preglomerular and TGF-controlled vascular resistance elements and the established pharmacological actions of ANP.

Alpha-h-ANP is the only form of circulating ANP in humans

Alpha-human atrial natriuretic peptide (alpha-h-ANP) was purified to homogeneity from human plasma of healthy adults in a three-step procedure including immunoaffinity chromatography on immobilized monoclonal anti-alpha-h-ANP antibody (moab). A single peak of immunoreactivity was obtained after final reversed-phase HPLC and the amino acid sequence of the isolated material was identical to that of synthetic alpha-h-ANP. No further atrial peptides could be detected although the moab reacts with all biologically active peptides. It is therefore concluded that alpha-h-ANP is the only form of ANP circulating in human plasma.

The elevation of cyclic GMP as a response to acute hypervolemia is blocked by a monoclonal antibody directed against atrial natriuretic peptides

Substantial volume expansion in conscious rats induces a strong diuresis and natriuresis that is caused by the increase in plasma levels of atrial natriuretic peptides (ANP) as measured by a radioimmunoassay. This renal response could be blocked by monoclonal antibodies directed against ANP. Parallel to the change in ANP, the cyclic GMP levels in plasma, urine and kidney tissue were increased after volume loading and reduced after additionally given antibodies. From this study it seems to be clear that the cyclic GMP rise is not a direct effect of volume expansion but is specifically mediated by the released ANP.