Safety profile of the direct oral anticoagulants: an analysis of the WHO database of adverse drug reactions.

AIM: Direct oral anticoagulants (DOACs) have shown noninferiority to warfarin for stroke prevention in nonvalvular atrial fibrillation (AF) and a more promising safety profile. Unanswered safety aspects remain to be addressed and available evidence on the risk associated with these drugs are conflicting. In order to contribute to the debate on their safety profile, we conducted a comparative analysis of the reports of suspected adverse drug reactions (ADRs) associated with DOACs in VigiBase. METHODS: Study based on reports of suspected ADRs held in VigiBase as at December 2014, in which a DOAC or warfarin were administered in patients with nonvalvular AF and listed as suspected/interacting drugs. Medical Dictionary for Regulatory Activities was used to classify ADRs. Reporting odds ratio (ROR) with 95% confidence interval were calculated. Results with P ≤ 0.05 were statistically significant. RESULTS: We retrieved 32 972 reports. We identified 204 ADRs with a ROR >1 (P ≤ 0.05) and we focused on 105 reactions. Positive ROR emerged for DOACs and gastrointestinal haemorrhage compared with warfarin [(1.6 (1.47-1.75)], but no disproportionality with cerebral haemorrhage was found [0.31 (0.28-0.34)]. We identified other potential signals that have not been associated with DOACs previously. CONCLUSIONS: As well as premarketing authorization clinical trial studies, we found a reduced risk of intracranial haemorrhage, but an increased risk of gastrointestinal haemorrhage in patients treated with DOACs compared to warfarin. We provide new data and we highlight several differences between the three novel oral anticoagulants, in the rate and type of ADRs occurred.

3-Phenylalkyl-2H-chromenes and -chromans as novel rhinovirus infection inhibitors.

Following our studies on structure-activity relationships of anti-rhinovirus chromene and chroman derivatives, we designed and synthesized new series of 3-phenylalkyl-2H-chromenes and -chromans bearing differently sized, aliphatic linker chains between the two cycles. The cytotoxicity and the antiviral activity of the new compounds on human rhinovirus (HRV) serotype 1B and 14 infection were evaluated in HeLa cell cultures. Most of the tested compounds interfered with HRV1B multiplication in the micromolar or submicromolar concentrations while HRV14 was less susceptible. 3-[3-(4-Chlorophenyl)propyl]chroman (9c) was selected for preliminary mechanism of action studies due to its potent activity against both serotypes (IC50 of 0.48µM and 1.36µM towards HRV1B and 14, respectively) coupled with high selectivity (SI=206.18 and 73.26, respectively). Results of time of addition/removal studies suggest that 9c, similarly to related derivatives, behaves as a capsid binder interfering with some early events of the HRV1B infectious cycle.

Safety profile of H1-antihistamines in pediatrics: an analysis based on data from VigiBase.

PURPOSE: H1-antihistamines are commonly used in infants and children for the relief of histamine-mediated symptoms in a variety of conditions. Little is known about their safety profile in these patients. We performed a comparative analysis of the safety profiles of H1-antihistamines using data from the WHO database (VigiBase). METHODS: We selected adverse drug reaction (ADR) reports on H1-antihistamines in children (0-16 years) up to June 2014 from VigiBase. ADRs were codified according to MedDRA terminology. The reporting odds ratios (RORs) with 95% confidence for drug-reaction pairs were calculated. RESULTS: The analysis was performed on 8918 reports related to antihistamines, corresponding to 19503 drug reaction pairs for 68 different drugs. Most of reports involved children aged 2 to 6 years (32%) and 6 to 12 years (34%). Most reported drugs were cetirizine (1608 reports, corresponding to 18%), loratadine (16%), and diphenhydramine (10%). ADRs were classified as serious in 23% of cases, and 400 cases had a fatal outcome. We found a significant associations for several drug-reaction pairs such as levocetirizine and epilepsy (ROR, 6.57; 95% confidence interval [CI], 1.51-28.53) and chlorphenamine and toxic epidermal necrolysis (ROR, 7.29; 95% CI, 2.39-22.2). CONCLUSIONS: H1-antihistamines are among the most used drugs in pediatrics, also in an off-label manner. Our data highlights associations with serious and unexpected ADRs. Educative intervention to clinicians and parents are needed to help doctors to make proper choices on the drug treatment and for the early detection of ADRs to maximize the benefits and reduce the risk of ADRs in these patients.

Ibuprofen-associated hypothermia in children: analysis of the Italian spontaneous reporting database.

PURPOSE: An analysis of Italian spontaneous adverse drug reactions (ADR) reporting database highlighted a potential association between hypothermia and ibuprofen in children. Hypothermia is defined as a core body temperature of 35 °C (95 °F). Ibuprofen is the most prescribed NSAID for the treatment of fever and moderate pain in children. We aimed to analyze the cases of ibuprofen-associated hypothermia retrieved in the Italian database in order to contribute to the discussion on this potential association. METHODS: We extracted all suspected cases of ibuprofen-associated hypothermia from the Italian spontaneous reporting database and from VigiBase up to December 2015. We considered the proportional reporting ratio (PRR) as a measure of disproportionality for the Italian cases and the information component (IC) for the reports from VigiBase. We performed a case-by-case analysis to exclude duplicates. RESULTS: Nineteen cases of hypothermia associated with ibuprofen use were retrieved from the Italian spontaneous reporting database (PRR 19.8, CI 95 %, 12.0-32.9). The reports concerned ten females and nine males with an average age of 2.5 years. Up to 31 December 2015, 168 cases of hypothermia associated with ibuprofen were reported to VigiBase, with an IC of 2.05 (IC025, 1.82). Among these, 126 cases involved children (49 % males) with an average age of 4.4 years. CONCLUSIONS: Although the risk of this ADR is unknown so far, the widespread use of this drug recommends the need for further studies to better characterize this possible association. Clinicians and pharmacists but also parents should be aware that this risk is theoretical as not yet been confirmed.

Synthesis and anti-rhinovirus activity of novel 3-[2-(pyridinyl)vinyl]substituted -2H-chromenes and -4H-chromen-4-ones.

Human rhinoviruses (HRVs) are the most common cause of viral respiratory infections and their complications. So far, no anti-viral agent has been approved for prevention or treatment of HRV infections. Pursuing our researches on small molecules with anti-rhinovirus activity, in this paper we describe the synthesis and in vitro anti-HRV 1B and 14 properties of new [2-(2H-chromen-3-yl)vinyl]pyridines and 3-[2-(pyridinyl)vinyl]-4H-chromen-4-ones. Generally, the synthesized compounds interfered with the replication of both serotypes at the micromolar or submicromolar concentrations. Preliminary results on their mechanism of action, performed on selected (E)-2-[2-(2H-chromen-3-yl)vinyl]pyridine, indicate an interference with the early step(s) of HRV 1B and 14 replication, probably at the uncoating level.

Design, synthesis, and in vitro hMAO-B inhibitory evaluation of some 1-methyl-3,5-diphenyl-4,5-dihydro-1H-pyrazoles.

A series of 1-methyl-3,5-diphenyl-4,5-dihydro-1H-pyrazoles (3a-k and 4a-u) were designed, synthesized, and evaluated for their inhibitory efficacy towards the two hMAO isoforms. Most of the derivatives were found to be potent and selective hMAO-B inhibitors. In particular, derivative 3g showed greater hMAO-B affinity than selective inhibitor selegiline coupled with high selectivity index (SI=145). The most selective hMAO-B inhibitor was the 3-methyl analogue 3f with an SI higher than 909.

Design, synthesis and in vitro evaluation of novel chroman-4-one, chroman, and 2H-chromene derivatives as human rhinovirus capsid-binding inhibitors.

As part of an effort to generate broad-spectrum inhibitors of rhinovirus replication, novel series of (E)-3-[(E)-3-phenylallylidene]chroman-4-ones 1a-e, (E)-3-(3-phenylprop-2-yn-1-ylidene)chroman-4-ones 2a and 2b, (Z)-3-[(E)-3-phenylallylidene]chromans 3a-e, and (E)-3-(3-phenylprop-1-en-1-yl)-2H-chromenes 4a-d were designed and synthesized. All the compounds were tested in vitro for their efficacy against infection by human rhinovirus (HRV) 1B and 14, two representative serotypes for rhinovirus group B and A, respectively. Most of the analogues were found to be potent and selective inhibitors of both HRVs, although HRV 1B was generally more susceptible than HRV 14. Mechanism of action studies of (E)-6-chloro-3-(3-phenylprop-1-en-1-yl)-2H-chromene 4b, the most potent compound on HRV 1B infection, suggested that 4b behaves as a capsid-binder probably acting at the uncoating level.

Design, Synthesis, Antiviral Evaluation, and SAR Studies of New 1-(Phenylsulfonyl)-1H-Pyrazol-4-yl-Methylaniline Derivatives.

A series of N-((3-phenyl-1-(phenylsulfonyl)-1H-pyrazol-4-yl)methyl)anilines 7a-p and 8a-l, structurally related to previously synthesized and tested (N-(1,3-diphenyl-1H-pyrazol-4-yl)methyl)anilines (1a-v), were designed and synthesized. The new derivatives were evaluated in cell-based assays for their cytotoxicity and antiviral activity against a large panel of RNA and DNA viruses of public health significance. Generally, the tested compounds did not display cytotoxicity toward the cell lines used. The majority of derivatives 7a-p were able to interfered with YFV and RSV replication in the micromolar range showing a marked improvement in potency and selectivity with respect to the reference inhibitors 6-azauridine and ribavirin, respectively. The introduction of a p-methoxy substituent on the phenylsulfonyl group (compounds 8a-l) completely abolished the anti-RSV activity and reduced or eliminated the potency against YFV. On the contrary, several p-methoxy analogs were able to interfere with BVDV replication with a comparable (8b, 8c, 8g, and 8k) or better (8a and 8f) potency than the reference inhibitor, ribavirin. Compound 7e, selected for time of addition experiments on BHK-21 cell cultures infected with YFV, achieved the highest reduction of virus titer when added 2 h post infection and maintained up to 4 h post infection.

Signal detection activity on EudraVigilance data: analysis of the procedure and findings from an Italian Regional Centre for Pharmacovigilance.

BACKGROUND: In July 2012 a new European legislation (Directive 2010/84/EU and Regulation No. 1235/2010) regarding pharmacovigilance has become effective. It has boosted the activity of Signal Detection through a monthly analysis of potential safety signals on EudraVigilance (EV). Our aim is to describe the procedure of signal detection on EV data and to present results obtained by the our pharmacovigilance centre. METHOD: Data are extracted from EV database, which collects suspected Adverse Drug Reactions (ADRs) of medicinal products in Europe. We are appointed to supervise digoxin, nicardipine, delapril, manidipine and hydrochlorothiazide/ramipril. ADRs are coded through MedDRA Preferred Terms and collected in the electronic Reaction Monitoring Report (eRMR). Statistical analysis is based on the Proportional Reporting Ratio (PRR) as a measure of disproportionality. RESULTS: Up to April 2016 we have analyzed 45 eRMR for each drug. Two signals for nicardipine were submitted to the Pharmacovigilance Risk Assessment Committee of European Medicines Agency (EMA): acute pulmonary oedema (off-label use as tocolytic) and thrombocytopenia. CONCLUSIONS: Our experience shows the scientific and regulatory value of signal detection activity on EV data in order to continuously evaluate the benefit/risk profile of recent and older drugs.

(E)-3-Heteroarylidenechroman-4-ones as potent and selective monoamine oxidase-B inhibitors.

A series of (E)-3-heteroarylidenechroman-4-ones (1a-r) was designed, synthesized and investigated in vitro for their ability to inhibit the enzymatic activity of both human monoamine oxidase (hMAO) isoforms, hMAO-A and hMAO-B. All the compounds were found to be selective hMAO-B inhibitors showing IC50 values in the nanomolar or micromolar range. (E)-5,7-Dichloro-3-{[(2-(dimethylamino)pyrimidin-5-yl]methylene}chroman-4-one (1c) was the most interesting compound identified in this study, endowed with higher hMAO-B potency (IC50 = 10.58 nM) and selectivity (SI > 9452) with respect to the reference selective inhibitor selegiline (IC50 = 19.60 nM, IC50 > 3431). Molecular modelling studies were performed for rationalizing at molecular level the target selective inhibition of our compounds, revealing a remarkable contribution of hydrogen bond network and water solvent.

1,5-Diphenylpenta-2,4-dien-1-ones as potent and selective monoamine oxidase-B inhibitors.

A series of (2E,4E)-1-(2-hydroxyphenyl)-5-phenylpenta-2,4-dien-1-ones (3a-r) and (2Z,4E)-3-hydroxy-1-(2-hydroxyphenyl)-5-phenylpenta-2,4-dien-1-ones (6a-l) were synthesized and evaluated in vitro as inhibitors of the two human Monoamine oxidase (hMAO) isoforms, MAO-A and MAO-B. Most of the compounds showed a selective MAO-B inhibitory activity in the nanomolar or low micromolar range. (2E,4E)-5-(4-Chlorophenyl)-1-(2-hydroxy-4-methoxyphenyl)penta-2,4-dien-1-one (3g) and (2E,4E)-5-(4-chlorophenyl)-1-(2,4-dihydroxyphenyl)penta-2,4-dien-1-one (3h) were the most potent hMAO-B inhibitors exhibiting IC(50) of 4.51 nM and 11.35 nM, respectively, coupled with high selectivity. Moreover, partial recovery of MAO-B activity was observed after repeated washing in the presence of isatin (reversible inhibitor) and compounds 3g and 3h suggesting a reversible inhibition of the enzyme. Molecular mechanics and quantum chemistry methods were used to elucidate the MAO recognition of the most active inhibitors 3g and 3h.

Homoisoflavonoids: natural scaffolds with potent and selective monoamine oxidase-B inhibition properties.

A series of homoisoflavonoids [(E)-3-benzylidenechroman-4-ones 1a-w, 3-benzyl-4H-chromen-4-ones 2a-g, and 3-benzylchroman-4-ones 3a-e] have been synthesized and tested in vitro as inhibitors of human monoamine oxidase isoforms A and B (hMAO-A and hMAO-B). Most of the compounds were found to be potent and selective MAO-B inhibitors. In general, the (E)-3-benzylidenechroman-4-ones 1a-w showed activities in the nano- or micromolar range coupled with high selectivity against hMAO-B. The reduction of the exocyclic double bond results in compounds 3a-e selective against isoform B and active in the micromolar range. In contrast, the endocyclic migration of the double bond (compounds 2a-g) generally produces the loss of the inhibitory activity or a marked reduction in potency. (E)-3-(4-(Dimethylamino)benzylidene)chroman-4-one (1l) and (E)-5,7-dihydroxy-3-(4-hydroxybenzylidene)chroman-4-one (1h) were the most interesting compounds of the entire series of inhibitors, showing hMAO-B affinity better than the selective inhibitor selegiline. Molecular modeling studies have been carried out to explain the selectivity of the most active homoisoflavonoids 1h and 1l.