Case–non-case studies: Principle, methods, bias and interpretation

Withdrawal syndrome after antipsychotics discontinuation: an analysis of the WHO database of spontaneous reports (Vigibase) between 2000 and 2022

RATIONALE

Withdrawal syndrome (WDS) has been described after discontinuation of antipsychotics. WDS could be the consequence of an over-activation of the dopaminergic pathway. Antipsychotics with a higher affinity for dopamine D2 receptors could be associated with a higher risk of WDS. This study aims to address this statement and evaluate the risk difference for withdrawal syndrome between antipsychotics based on pharmacovigilance data.

METHODS

We collected individual reports registered in Vigibase® between 01/01/2000 and 31/12/2022 of patients treated with antipsychotics and who had presented WDS. A disproportionality analysis was performed to evaluate the risk of reporting WDS with each antipsychotic compared to all other antipsychotics. We performed a correlation analysis to assess the correlation between the risk of reporting WDS for each antipsychotic in relation with their pKi for D2 and 5HT2A receptors.

RESULTS

The most frequent psychiatric withdrawal symptoms after antipsychotic discontinuation were insomnia, anxiety and depression. Tremor, headache and dizziness were among the most frequently reported neurologic withdrawal symptoms. Tiotixene had the highest risk of reporting WDS (ROR 7.08; 95%CI 3.49 - 14.35) followed by pimozide (ROR 4.35; 95%CI 1.93 - 9.77), quetiapine (ROR 4.24; 95%CI 3.87 - 4.64), thioridazine (ROR 4.17; 95%CI 2.50-6.98) and ziprasidone (ROR 2.98; 95%CI 2.41-3.67). We found a poor correlation between D2/5HT2A binding affinity and the risk of reporting withdrawal syndrome (R2 = 0,094).

CONCLUSION

Our results suggest that there might be a risk difference for WDS between antipsychotics. Tiotixene, pimozide and quetiapine were associated with a higher risk of reporting a WDS whereas this risk was lower with chlorpromazine, clozapine and fluphenazine. We could not address the issue of withdrawal psychosis, withdrawal dyskinesia, rebound psychosis or supersensitivity psychosis due to the lack of specific WHO medDRA coded terms to identify potential cases.

The REporting of A Disproportionality Analysis for DrUg Safety Signal Detection Using Individual Case Safety Reports in PharmacoVigilance (READUS-PV): Explanation and Elaboration

In pharmacovigilance, disproportionality analyses based on individual case safety reports are widely used to detect safety signals. Unfortunately, publishing disproportionality analyses lacks specific guidelines, often leading to incomplete and ambiguous reporting, and carries the risk of incorrect conclusions when data are not placed in the correct context. The REporting of A Disproportionality analysis for drUg Safety signal detection using individual case safety reports in PharmacoVigilance (READUS-PV) statement was developed to address this issue by promoting transparent and comprehensive reporting of disproportionality studies. While the statement paper explains in greater detail the procedure followed to develop these guidelines, with this explanation paper we present the 14 items retained for READUS-PV guidelines, together with an in-depth explanation of their rationale and bullet points to illustrate their practical implementation. Our primary objective is to foster the adoption of the READUS-PV guidelines among authors, editors, peer reviewers, and readers of disproportionality analyses. Enhancing transparency, completeness, and accuracy of reporting, as well as proper interpretation of their results, READUS-PV guidelines will ultimately facilitate evidence-based decision making in pharmacovigilance.

Thirst and drugs: A study in the World Health Organization's pharmacovigilance database

Thirst is a complex physiological compensatory mechanism but could also be associated with drugs. This association was poorly investigated previously. Using the WHO global pharmacovigilance database, Vigibase®, disproportionality analyses potential associations between exposure to drugs and thirst reports were performed. All reports of thirst in adults between 01/01/2000 and 31/12/2023 were included. Results are expressed as reporting odds ratio (ROR). Analysis of the 3186 reports of thirst (978 'serious') allowed, first, to confirm the association between thirst and exposure to vasopressin antagonists (tolvaptan), lithium, gliflozins (dapagliflozin, empagliflozin), pregabalin and antimuscarinic drugs (glycopyronium, oxybutynin, tiotropium). Second, new safety signals were described with monoamine reuptake inhibitors (antidepressants: duloxetine, venlafaxine; anti-obesity agent: sibutramine), antipsychotic (olanzapine), glucocorticoid (prednisolone), diuretic (furosemide) drugs as well with ribavirin or sodium oxybate. This study is the first to offer a list of drugs associated with thirst in humans.

The Reporting of a Disproportionality Analysis for Drug Safety Signal Detection Using Individual Case Safety Reports in PharmacoVigilance (READUS-PV): Development and Statement

BACKGROUND AND AIM

Disproportionality analyses using reports of suspected adverse drug reactions are the most commonly used quantitative methods for detecting safety signals in pharmacovigilance. However, their methods and results are generally poorly reported in published articles and existing guidelines do not capture the specific features of disproportionality analyses. We here describe the development of a guideline (REporting of A Disproportionality analysis for drUg Safety signal detection using individual case safety reports in PharmacoVigilance [READUS-PV]) for reporting the results of disproportionality analyses in articles and abstracts.

METHODS

We established a group of 34 international experts from universities, the pharmaceutical industry, and regulatory agencies, with expertise in pharmacovigilance, disproportionality analyses, and assessment of safety signals. We followed a three-step process to develop the checklist: (1) an open-text survey to generate a first list of items; (2) an online Delphi method to select and rephrase the most important items; (3) a final online consensus meeting.

RESULTS

Among the panel members, 33 experts responded to round 1 and 30 to round 2 of the Delphi and 25 participated to the consensus meeting. Overall, 60 recommendations for the main body of the manuscript and 13 recommendations for the abstracts were retained by participants after the Delphi method. After merging of some items together and the online consensus meeting, the READUS-PV guidelines comprise a checklist of 32 recommendations, in 14 items, for the reporting of disproportionality analyses in the main body text and four items, comprising 12 recommendations, for abstracts.

CONCLUSIONS

The READUS-PV guidelines will support authors, editors, peer-reviewers, and users of disproportionality analyses using individual case safety report databases. Adopting these guidelines will lead to more transparent, comprehensive, and accurate reporting and interpretation of disproportionality analyses, facilitating the integration with other sources of evidence.

Acetazolamide-induced pulmonary oedema: A disproportionality analysis from the EudraVigilance database

To our knowledge, no prior study has analysed a possible association between acetazolamide and pulmonary oedema. The aim of this study was to use data from the EudraVigilance to detect a safety signal for acetazolamide-induced pulmonary oedema. We performed a disproportionality analysis (case-noncase method), calculating reporting odds ratios (RORs) up to 22 February 2024. Among 11 684 208 spontaneous cases of adverse reactions registered in EudraVigilance, 38 275 were pulmonary oedemas. Acetazolamide was involved in 31 cases. In more than half of those cases, the patients received a single dose of acetazolamide after undergoing cataract surgery: latency was 10-90 min. Remarkably, there were five cases of positive rechallenge and six cases resulted in death. The ROR for acetazolamide was 3.63 (95% CI 2.55-5.17). Disproportionality was also observed in VigiBase®: ROR 4.44 (95% CI 3.34-5.90). Our study confirms a signal that suggests a risk of serious pulmonary oedema associated with acetazolamide.

Exploring the association between suicidal thoughts, self-injury, and GLP-1 receptor agonists in weight loss treatments: Insights from pharmacovigilance measures and unmasking analysis

INTRODUCTION

The study addresses concerns about potential psychiatric side effects of Glucagon-like peptide-1 receptor agonists (GLP-1 RA).

AIM

The aim of this work was to analyse adverse drug reports (ADRs) from the Food and Drug Administration Adverse Events Reporting System (FAERS) using metformin and orlistat as comparators.

METHODS

Descriptive and pharmacovigilance disproportionality analyses was performed.

RESULTS

A total of 209,354 ADRs were reported, including 59,300 serious cases. Of those, a total of 5378 psychiatric disorder cases, including 383 'serious' cases related to selected ADRs were registered during 2005-2023. After unmasking, 271 cases where individual GLP-1 RA were implicated showing liraglutide (n = 90; Reported Odds Ratio (ROR) = 1.64), exenatide (n = 67; ROR = 0.80), semaglutide (n = 61; ROR = 2.03), dulaglutide (n = 45; ROR = 0.84), tirzepatide (n = 5; ROR = 1.76) and albiglutide (n = 2; ROR = 0.04). A greater association between these ADRs with metformin was observed, but not orlistat. With regards to selected preferred terms (PTs), 42 deaths including 13 completed suicides were recorded. Suicidal ideation was recorded in n = 236 cases for 6/7 GLP-1 RA (excluding lixisenatide).

DISCUSSION

Suicide/self-injury reports pertaining to semaglutide; tirzepatide; and liraglutide were characterised, although lower than metformin. It is postulated that rapid weight loss achieved with GLP-1 RA can trigger significant emotional, biological, and psychological responses, hence possibly impacting on suicidal and self-injurious ideations.

CONCLUSIONS

With the current pharmacovigilance approach, no causality link between suicidal ideation and use of any GLP-1 RA can be inferred. There is a need for further research and vigilance in GLP-1 RA prescribing, particularly in patients with co-existing psychiatric disorders.

Multiple myeloma, haematologic malignancy and immunosuppressant and immunomodulatory medications are associated with sebaceous carcinoma, a pharmacovigilance study of the FDA adverse event reporting system

BACKGROUND

Sebaceous carcinoma (SC) is a rare skin cancer with significant associated morbidity and mortality. A known association exists between immunosuppression, in particular solid organ transplant patients (SOTR), and SC. However, the comparative reporting odds ratios (ROR) of different immunosuppressive medications and SC are incompletely defined.

OBJECTIVES

To examine the relationship between SC and medication exposure in the FDA adverse event reporting system (FAERS).

METHODS

Case-control analyses were performed in FAERS from 1968 to 2021 to examine the reporting odds ratios (ROR) for SC.

RESULTS

A total of 58 medication-associated SC cases were identified. Immunosuppressant medication exposure was noted in 81% cases, with 20% total cases occurring in SOTR. Medications affecting the TNF- α -IL-1-IL-2-IL-6 inflammatory axis were associated with elevated ROR for SC, including thalidomide (ROR 22.63, 95% CI 5.52-92.72), lenalidomide (ROR 10.86, 95% CI 4.93-23.94), cyclosporine, tacrolimus, tocilizumab, tofacitinib and ruxolitinib. Thirty per cent of cases of SC occurred with an associated haematologic malignancy or dyscrasia, including chronic lymphocytic leukaemia, non-Hodgkin lymphoma and multiple myeloma.

CONCLUSIONS

SC is associated with exposure to immunosuppressive medications, especially in SOTR patients. A significant portion of cases with SC had an associated haematology malignancy, in particular multiple myeloma with exposure to lenalidomide.

Drug-related catatonia in youths: real-world insights from the WHO Safety Database

Catatonia is characterized by psychomotor alterations and reduced contact with the environment. Initially linked to schizophrenia, it also occurs in mood disorders or organic conditions. In children, catatonia remains poorly delineated, despite dramatically increasing the risk of premature death. As data on pediatric drug-induced catatonia bears many uncertainties, we aimed to characterize its age-dependent patterns, using real-world data from the WHO safety database (VigiBase®).VigiBase® was queried for all reports of catatonia registered up to December 8th 2022. Reports involving patients <18 years were classified into 3 groups: ≤23 months, 2-11 years, and 12-17 years. Disproportionality analyses relied on the Reporting Odds Ratio (ROR), and the positivity of the lower end of the 95% confidence interval of the Information Component (IC) was required to suspect a signal. Catatonia was evoked in 421 pediatric reports. In infants, vaccines were leading. In children, the main signals involved haloperidol (ROR 104.3; 95% CI 45.6-238.5), ondansetron (ROR 40.5; 95% CI 16.5-99.5), and ciclosporin (ROR 27.4; 95% CI 13.8-54.1). In adolescents, chlorpromazine (ROR 199.1; 95% CI 134.8-294.1), benzatropine (ROR 193; 95% CI 104.1-361.6), and olanzapine (ROR 135.7; 95% CI 104.6-175.9) reached the highest RORs. In infants, catatonia was related to vaccines, it was ascribed to multiple drugs in children, and mainly to psychotropic drugs in adolescents. Less suspected drugs, such as ondansetron, were highlighted. Despite limitations inherent in spontaneous reporting systems, this study supports that a careful anamnesis is warranted to separate catatonia associated with medical conditions from drug-induced catatonia in pediatric patients.

Severe cutaneous adverse reactions associated with the immune checkpoint inhibitors: A case/non-case analysis using the Food and Drug Administration Adverse Event Reporting System

BACKGROUND/OBJECTIVES

The immune checkpoint inhibitors (ICIs) have been increasingly associated with severe cutaneous adverse reactions (SCARs). These reactions, including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalized exanthematous pustulosis (AGEP) are uncommon but potentially lethal. Despite the severity of these reactions and growing association with the ICIs, their specific risk and mortality rates have been largely unexplored.

METHODS

A case/non-case analysis was performed using data from the United States Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) to examine the reporting odds ratios (RORs) for ICI-associated SCARs cases under two conditions: (1) ICIs compared with all drugs in FAERS and (2) ICIs compared with a reference group of pooled anticancer drugs to control for underlying malignancy.

RESULTS

A statistically significant ROR for SJS (ROR: 5.44), TEN (ROR: 5.81) and DRESS (ROR: 1.38) were identified under Condition 1. Under Condition 2, this significance was maintained for SJS (ROR: 7.31), TEN (ROR: 7.40) and DRESS (ROR: 3.90), and mild significance was identified for AGEP (ROR: 1.89). Mortality rates for the ICIs were increased compared with the anticancer medications (28.5% vs. 24.5% for SJS, 55.3% vs. 46% for TEN, 3.0% vs. 2.1% for AGEP and 7.1% vs. 6.1% for DRESS).

CONCLUSIONS

Our results suggest an association between SCARs and the ICIs independent of cancer status.

Statins and immune-mediated necrotizing myopathy: Variability in the risk

INTRODUCTION

Immune-mediated necrotizing myopathy (IMNM) is a form of statin myopathy characterized by the presence of antibodies against 3-hydroxy-3-methylglutaryl-coenzyme A reductase (anti HMGCR).

OBJECTIVES

The aim of this study was to investigate the relationship between the different statins and the risk of IMNM.

METHODS

A two-time approach was used. First, we performed a descriptive analysis of the French national pharmacovigilance database (FNPV) for the period from 1985 to december2020. To identify relevant cases, we used Medical Dictionary for Regulatory Activities (MedDRA) preferred terms (PTs) related to IMNM. We performed a quantitative and qualitative review of individual case safety reports (ICSRs) recorded in the french vigilance spontaneous reporting system. In a second time, we performed a comparative analysis with the World Health Organization global individual case safety reports database (Vigibase). The association between IMNM and statins exposure was assessed by calculating the reporting odds ratio (ROR) and its 95% confidence interval.

RESULTS

After analysis, a total of 25 ICSRs were related to IMNM in the FNPV. The suspected statins were atorvastatin (n=21), simvastatin (n=2), pravastatin (n=1) and rosuvastatin (n=1). In Vigibase, 567 notifications were identified. A significant ROR value was found for atorvastatin, pitavastatin, simvastatin, pravastatin and rosuvastatin.

CONCLUSION

Atorvastatin presents the highest risk of IMNM. Our data suggest that the occurrence of IMNM is a class effect.

Emerging Toxicities of Antibody-Drug Conjugates for Breast Cancer: Clinical Prioritization of Adverse Events from the FDA Adverse Event Reporting System

BACKGROUND

Antibody-drug conjugates (ADCs) are gaining widespread use in the treatment of breast cancer, although toxicity remains an underexplored issue in the real-world clinical setting. Individual case safety reports collected in large pharmacovigilance databases can advance our knowledge on their safety profile in routine clinical practice.

OBJECTIVE

We prioritized adverse events (AEs) reported with ADCs approved for breast cancer using the Food and Drug Administration Adverse Event Reporting System (FAERS).

METHODS

We assessed clinical priority of AEs reported in FAERS (February 2013-March 2022) for trastuzumab emtansine (T-DM1), trastuzumab deruxtecan (T-DXd), and sacituzumab govitecan (SG) by attributing a score to each AE disproportionally reported with ADCs. Four criteria were assessed: clinical relevance, reporting rate, reported case fatality rate, and stability of disproportionality signals (consistency of the reporting odds ratio across multiple analyses using three different comparators).

RESULTS

We retained 6589 reports (77.4% referring to T-DM1 as suspect), and 572 AEs generated a disproportionality signal in at least one analysis. The majority of these AEs (62%) were classified as moderate clinical priorities (e.g., interstitial lung disease with T-DXd, thrombocytopenia, peripheral neuropathy with T-DM1, febrile neutropenia, and large intestine perforation with SG). Three AEs emerged as high clinical priorities (6 points): septic shock and neutropenic colitis with SG (N = 8 and 13, with median onset 13 and 10 days, respectively), without co-reported immunosuppressive agents; and pulmonary embolism with T-DM1 (N = 31, median onset 109 days, 52% with reported metastasis).

CONCLUSION

The heterogeneous spectrum of post-marketing toxicities for ADCs used in breast cancer, as emerging from the FAERS, is largely in line with preapproval evidence. Although causality cannot be proved, we call for increased awareness by oncologists on potential serious unexpected reactions, including early onset of septic shock and neutropenic colitis with SG, and late emergence of pulmonary embolism with T-DM1.

Drug-related hypophosphatemia: Descriptive study and case/non-case analysis of the French national pharmacovigilance database

Phosphorus is an essential element for all living organisms and is involved in various biological pathways. A severe hypophosphatemia can lead to serious complications (acute heart or respiratory failure, rhabdomyolysis, hemolysis…) and increases mortality in patients at risk. Various drugs are known to induce hypophosphatemia through various mechanisms. The aim of this study was to highlight the main drugs associated with hypophosphatemia and to deduce the underlying mechanisms based on a descriptive analysis and a case/non-case analysis using the cases of drug-induced hypophosphatemia reported to the French Pharmacovigilance Network. A total of 368 cases of hypophosphatemia were included in the study. Patients' mean age was 52±18 years. One hundred and ninety-one cases (52%) were serious including 131 (36%) hospitalizations. The median value of serum phosphorus level was 0.54mmol/L [0.40-0.66] (n=309). Those 368 cases corresponded to 185 different suspected substances among which the most frequent drugs were tenofovir disoproxil (n=175; 48%), ferric carboxymaltose (n=29; 8%), denosumab (n=16; 4%), zoledronic acid (n=14; 4%) and hydrochlorothiazide (n=10; 3%). For these five drugs, a significant disproportionality was found. Tenofovir-disoproxil related hypophosphatemia occurred more than one year after its introduction, and a renal tubulopathy (Fanconi's syndrome) was reported in 44 cases (25%). Hypophosphatemia related to iron carboxymaltose occurred within a median of 20 days after injection and was mostly severe. Mechanism included the fibroblast growth factor 23 which can be measured to confirm drug origin. Concerning anti-osteoporosis treatments, hypophosphatemia could be explained by their mechanism of action (abrupt increase of parathormone induced by hypocalcemia) but the patient history (malignancy condition) was a major bias. For hydrochlorothiazide, hyphosphatemia was often moderate, associated with other electrolytic disturbances and occurred during a long-term treatment. Awareness of healthcare professionals is essential to detect as soon as possible hypophosphatemia and its complications related to these drugs.

Psychosis with use of amphetamine drugs, methylphenidate and atomoxetine in adolescent and adults

BACKGROUND

Use of psychostimulants and relative drugs has increased worldwide in treatment of attention-deficit hyperactivity disorder (ADHD) in adolescents and adults. Recent studies suggest a potential association between use of psychostimulants and psychotic symptoms. The risk may not be the same between different psychostimulants.

OBJECTIVE

To assess whether amphetamine or atomoxetine use is associated with a higher risk of reporting symptoms of psychosis than methylphenidate use in adolescents and adults, particularly in patients with ADHD.

METHODS

Using VigiBase, the WHO's pharmacovigilance database, disproportionality of psychotic symptoms reporting was assessed among adverse drug reactions related to methylphenidate, atomoxetine and amphetamines, from January 2004 to December 2018, in patients aged 13-25 years. The association between psychotic symptoms and psychostimulants was estimated through the calculation of reporting OR (ROR).

FINDINGS

Among 13 863 reports with at least one drug of interest, we found 221 cases of psychosis with methylphenidate use, 115 with atomoxetine use and 169 with a prescription of an amphetamine drug. Compared with methylphenidate use, amphetamine use was associated with an increased risk of reporting psychotic symptoms (ROR 1.61 (95% CI 1.26 to 2.06)]. When we restricted the analysis to ADHD indication, we found a close estimate (ROR 1.94 (95% CI 1.43 to 2.64)). No association was found for atomoxetine.

CONCLUSION

Our study suggests that amphetamine use is associated with a higher reporting of psychotic symptoms, compared with methylphenidate use.

CLINICAL IMPLICATIONS

The prescription of psychostimulants should consider this potential adverse effect when assessing the benefit-risk balance.

Exploring signals of myopathy associated with statin and contraindicated comedications in the realworld

BACKGROUND

Using statins in combination with other drugs was reported to increase the risk of myopathy. However, there was a sparse number of studies on the incidence of adverse events (AEs) associated with the concomitant use of statin and contraindicated drugs in the real world.

OBJECTIVES

This study aimed to identify the risk of concomitant use of statins with contraindicated drugs by exploring signals related to statin-drug interactions.

METHODS

We performed a disproportionality analysis for drugs and AEs by applying the case/non-case study using the KIDS-KAERS database (KIDS-KD), 2016-2020. A case was defined as an individual case safety reports (ICSRs) including "rhabdomyolysis/myopathy." A non-case was defined as an ICSR, including all other AEs. We applied Ω shrinkage measure model, chi-square statics model, additive model, multiplicative model, and combination risk ratio model to detect signals of myopathy due to statin with concomitant drugs including antiviral agents, immunosuppressants, and antifungals.

RESULTS

Among 1 011 234 ICSRs, 2708 were cases, with 861 cases of statin monotherapy and 1248 of concomitant uses of statin. The adjusted reporting odds ratios were 3.27 (95% confidence interval [CI]: 3.11-3.43), 8.70 (95% CI: 8.04-9.40), and 1.83 (95% CI: 1.73-1.94), respectively. Several combinations of signals were detected through an additive model or multiplicative model.

CONCLUSION

Signals of an increased risk of myopathy associated with the use of statins with concomitant drugs, including contraindicated drugs, were confirmed in a real-world setting.

Drug-induced depressive symptoms: An update through the WHO pharmacovigilance database

BACKGROUND

Depression is a highly incident condition and some drugs have been described as inducing or worsening depression. However, literature on this topic is rare and possibly outdated.

METHODS

We performed disproportionality analyses using VigiBase®, the largest pharmacovigilance database worldwide to identify drugs associated with depression. Then we excluded drugs already known as depressogenic according to American Summary of Product Characteristics (SPC). We then reviewed drug mechanism of action, scientific literature and European SPC for each drug identified to assess a level of plausibility. We measured Reporting Odds Ratio (ROR) statistically significant and superior to 1, suggesting a significant association between a drug and the reporting of depressive symptoms.

RESULTS

Out of the 5237 drugs extracted on VigiBase®, we have retained 89 new drugs associated with depression. More than half of drugs of interest are from nervous system. Opicapone (ROR: 20.66 95 %CI: 15.62-27.33), and gadoversetamide (ROR 18.62, 95 %CI 9.63-35.95) were the drugs with the highest ROR. Among the 89 drugs, 38 were considered already described such as suvorexant or ivacaftor, 20 likely associated such as anti-migraines drugs or new antipsychotic drugs and 31 potentially associated.

LIMITATIONS

Pharmacovigilance studies have many inherent limitations, such as under-reporting bias, notoriety effect and protopathic bias. These results are not intended to establish a causal link, only a statistical association.

CONCLUSION

We found a strong statistical signal and pharmacological plausibility for 58 new depressogenic drugs. This update list of suspected drugs may prove useful for doctors faced with potential cases of drug-induced depression or to stay aware in case. Other studies are needed to confirm the list.

Impact of the vaccination against SARS-CoV-2 campaign on disproportionality indicator from the WHO pharmacovigilance database: A competition bias study from case/non-case analysis

INTRODUCTION

The coronavirus disease 2019 (COVID-19) vaccination campaign has resulted in numerous pharmacovigilance's safety reports which were recorded in the World Health Organization (WHO) pharmacovigilance database (VigiBase) and represent in July 2022 more than 10% of cases recorded. The information component (IC) is a statistical disproportionality measure based on the observed and expected numbers of case reports. A positive value of the lower endpoint of a 95% credibility interval for the information component (IC0.25) suggests a possible causal relationship between the drug and the adverse reaction. This study aimed to evaluate the impact of the wave of COVID-19 vaccines safety declarations on IC0.25 from Vigilyze and thus illustrate with a concrete example the competition bias.

METHODS

We arbitrarily selected 21 adverse drug reactions using Medical Dictionary for Regulatory Activities (MedDRA) preferred terms (PTs), divided in two types: PTs known to be related to COVID-19 vaccines ("expected") and others (type "unexpected"). Data were extracted from VigiLyze. We created two groups: V+ (the full database, including COVID-19 vaccines reports) and V- (the same extraction without COVID-19 vaccine reports). IC0.25 was recomputed for the group V- and we compared the positive signal evolution in the two settings of selection (V+ and V- groups).

RESULTS

The number of positive potential signals was significantly different in the groups V+ and V- for IC0.25. We observed that most of the "unexpected" PTs lost potential signal after the withdrawal of COVID-19 reports. On the contrary, the majority of 'expected' PTs had potential new signals after the withdrawal of COVID-19 reports.

DISCUSSION

This study is one of the first to evaluate the effect of COVID-19 vaccines reporting on Automated Signal Detection of Pharmacovigilance. In this study, we observed that a wave of pharmacovigilance reporting can affect disproportionality estimators such as IC0.25 and then have an impact on automated signal detection; some signals disappear (almost with all PTs related to COVID-19 vaccines) and others appear (mostly with PTs not related to COVID-19 vaccines), illustrating the competition bias.

CONCLUSION

We show that a health crisis involving a change in drug use can affect adverse drug reactions reporting and pharmacovigilance databases, leading to competition bias and a change in the disproportionality analyses. For health professionals who use quantitative disproportionality analysis, it is important not only to use the crude values of indicators but also the kind of PTs and the evolution of the signal over time (take into account major events such as crises).

Drug-induced hyperglycemia and diabetes

BACKGROUND

Drug-induced hyperglycemia and diabetes have negative and potentially serious health consequences but can often be unnoticed.

METHODS

We reviewed the literature searching Medline database for articles addressing drug-induced hyperglycemia and diabetes up to January 31, 2023. We also selected drugs that could induce hyperglycemia or diabetes according official data from drug information databases Thériaque and Micromedex. For each selected drug or pharmacotherapeutic class, the mechanisms of action potentially involved were investigated. For drugs considered to be at risk of hyperglycemia or diabetes, disproportionality analyses were performed using data from the international pharmacovigilance database VigiBase. In order to detect new pharmacovigilance signals, additional disproportionality analyses were carried out for drug classes with more than 100 cases reported in VigiBase, but not found in the literature or official documents.

RESULTS

The main drug classes found to cause hyperglycemia are glucocorticoids, HMG-coA reductase inhibitors, thiazide diuretics, beta-blockers, antipsychotics, fluoroquinolones, antiretrovirals, antineoplastic agents and immunosuppressants. The main mechanisms involved are alterations in insulin secretion and sensitivity, direct cytotoxic effects on pancreatic cells and increases in glucose production. Pharmacovigilance signal were found for a majority of drugs or pharmacological classes identified as being at risk of diabetes or hyperglycemia. We identified new pharmacovigilance signals with drugs not known to be at risk according to the literature or official data: phosphodiesterase type 5 inhibitors, endothelin receptor antagonists, sodium oxybate, biphosphonates including alendronic acid, digoxin, sartans, linosipril, diltiazem, verapamil, and darbepoetin alpha. Further studies will be needed to confirm these signals.

CONCLUSIONS

The risks of induced hyperglycemia vary from one drug to another, and the underlying mechanisms are multiple and potentially complex. Clinicians need to be vigilant when using at-risk drugs in order to detect and manage these adverse drug reactions. However, it is to emphasize that the benefits of appropriately prescribed treatments most often outweigh their metabolic risks.

Hepatotoxicity of newer antiseizure medications in children: an overview and disproportionality analysis of VigiBase

BACKGROUND

We aimed to characterize newer antiseizure medications (ASMs)-induced hepatotoxicity in children and identify signals of disproportionate reporting of hepatotoxicity-related adverse drug events (ADEs).

RESEARCH DESIGN AND METHODS

Case reports reported to VigiBase were accessed using Empirica™ Signal software. To summarize characteristics of the retrieved cases, descriptive statistics were used. A disproportionality analysis was conducted using the Multi-item Gamma Poisson Shrinker algorithm, which calculates Empirical Bayesian Geometric Mean value and its lower and upper 95% confidence limits (EB05 and EB95, respectively). EB05 > 2, N > 0 was considered a signal.

RESULTS

Based on 870 analyzed cases, a higher proportion of cases was reported in girls than in boys and in patients aged 2-11 years than in other age groups. Most cases were serious. In 25 cases, hepatotoxicity resulted in death. A high proportion of patients (n = 275, 31.61%) experienced hypersensitivity reactions, mostly due to lamotrigine. The disproportionality analysis yielded 17 signals concerning felbamate, lamotrigine, levetiracetam, oxcarbazepine, stiripentol, and topiramate. Four signals were for severe liver injury and concerned felbamate, lamotrigine, levetiracetam, and topiramate. Gender-biased reporting frequency was detected for four ASM-ADE combinations.

CONCLUSION

Our results should serve to raise clinicians' awareness about the potential association between several newer ASMs and drug-induced liver injury in children.

Antibiotic-induced neurological adverse drug reactions

Antibiotics are drugs widely used all around the world. Central nervous system adverse drug reactions (CNS ADRs) are mostly under-suspected with antibiotics. Nevertheless, these ADRs could lead to severe complications such as encephalopathy. To illustrate the clinical patterns of these off-target ADRs, we here present data from pharmacovigilance system, through different populations and points of view (worldwide, French population, vulnerable population and individual). These data could help clinicians to better know about CNS ADRs with antibiotics, to better identify risk factors and vulnerable patients and to highlight the importance to set up the right diagnostic explorations in the best timing to avoid complications. Clinicians should request a pharmacological opinion from pharmacologist (biologists and pharmacovigilance clinicians) in front of vulnerable population before or during antibiotics. Pharmacovigilance advice could help clinicians in the diagnosis and the management of an ADR. Therapeutic drug monitoring is particularly contributive to adjust doses of antibiotics administered in vulnerable patients. Pharmacovigilance advice and TDM are essential to perform personalized medicine, and contribute to the proper use of drugs.

Drug-induced tumoral disease: A global pharmacovigilance database analysis

INTRODUCTION

Cancer remains a worldwide threat, having caused almost 10 million deaths in 2020. The American Cancer Society has identified both known and probable carcinogens, including commonly used drugs. The aim of this study is to describe the drugs most frequently reported in the occurrence of cancer.

METHODS

Among all individual case safety reports (ICSRs) in the global pharmacovigilance database VigiBase, we searched for the 50 most reported drugs with an adverse drug reaction term belonging to the query "Malignant or unspecified tumors" until June 30, 2023. Then, we extracted the disproportionality measurement data, information component (IC), and reporting odds ratio (ROR) in order to assess a disproportionality signal.

RESULTS

Among all ICSRs in VigiBase, 871,925 contained an ADR belonging to the SMQ "Malignant or unspecified tumors". Ranitidine was the drug with the most reported ADRs related to cancer (n=106,484), followed by lenalidomide (n=13,466), and etanercept (n=8014). The drugs with the highest IC were ranitidine (IC=5.2, 95% confidence interval [95% CI]=5.2-5.2), pioglitazone (1353 ICSRs, IC=4.2, 95% CI=4.2-4.2), and regorafenib (1272 ICSRs, IC=2.8, 95% CI=2.8-2.8).

DISCUSSION

Our results show that the main pharmacological mechanisms are associated with ranitidine (link with levels of N-nitrosodimethylamine in ranitidine-based drugs), gene-activating drugs (pioglitazone: link with agonist effects on PPAR-γ gene activation), various pharmacological families with immunosuppressive effects (protein kinase inhibitors, immunomodulators, azathioprine, etc.), certain types of protein kinase inhibitors whose oncogenic mechanisms remain unclear (regorafenib, sorafenib, imatinib, ibrutinib, etc.), and hormone antagonists (tamoxifen, letrozole). Special monitoring of patients exposed to these drugs may be required. Further studies are needed to assess the risk with certain drugs in this ranking.

Drug-induced immune hemolytic anemia: detection of new signals and risk assessment in a nationwide cohort study

ABSTRACT

More than 130 drugs have been suspected to induce immune hemolytic anemia. Comparative studies measuring the risk of drug-induced immune hemolytic anemia (DIIHA) are lacking. We aimed (1) to detect new signals of DIIHA, excluding vaccines, and (2) to assess the association between all suspected drugs and the occurrence of immune hemolytic anemia in a nationwide comparative study. The new signals were identified using a disproportionality study (case/noncase design) in the World Pharmacovigilance Database, Vigibase, among the cases of adverse drug reactions reported up to February 2020 (>20 million). We then conducted a comparative study in the French National health database that links sociodemographic, out-of-hospital, and hospital data for the entire population (67 million individuals). Associations between exposure to drugs (those already reported as DIIHA, plus new signals identified in Vigibase) and incident cases of immune hemolytic anemia (D59.0 and D59.1 diagnosis codes of the International Classification of Diseases, version 10) from 2012 to 2018 were assessed with case-control and case-crossover designs. In Vigibase, 3371 cases of DIIHA were recorded. Fifty-nine new signals were identified resulting in a final list of 112 drugs marketed in France and measurable in the nationwide cohort (n = 4746 patients with incident immune hemolytic anemia included in the case-control analysis matched with 22 447 controls from the general population). We identified an association between immune hemolytic anemia occurrence and some antibiotics, antifungal drugs, ibuprofen, acetaminophen, furosemide, azathioprine, and iomeprol.

Major cardiovascular events under biologic psoriasis therapies: a 19-year real-world analysis of FAERS data

Objective

Over the years when biologic psoriasis therapies (TNF inhibitors, IL-12/23 inhibitors, IL-23 inhibitors, and IL-17 inhibitors) have been used in psoriasis patients, reports of major cardiovascular events (MACEs) have emerged. This study aims to investigate the association between MACEs and biologic psoriasis therapies by using information reported to the US Food and Drug Administration Adverse Event Reporting System (FAERS).

Methods

FAERS data (January 2004 to December 2022) were reviewed. For each drug-event pair, the proportional reporting ratio (PRR) and the multi-item gamma Poisson shrinker (MGPS) algorithms were used to identify drug-adverse event associations.

Results

We filtered the query for indication and identified 173,330 reports with psoriasis indication in FAERS throughout the analyzed time frame. MACEs occurred in 4,206 patients treated with biologics. All the four biological classes had an elevated and similar reporting rates for MACEs relative to other alternative psoriasis treatments (PRR from 2.10 to 4.26; EB05 from 1.15 to 2.45). The descending order of association was IL-12/23 inhibitors>IL-17 inhibitors>IL-23 inhibitors>TNF inhibitors. The signal strength for myocardial infarction (PRR, 2.86; χ2, 296.27; EBGM 05, 1.13) was stronger than that for stroke, cardiac fatality, and death. All the biological classes demonstrated a little higher EBGM 05 score≥1 for the MACEs in patients aged 45-64 years. The time-to-onset of MACEs was calculated with a median of 228 days.

Conclusions

Analysis of adverse event reports in the FAERS reflects the potential risk of MACEs associated with the real-world use of biological therapies in comparison to other alternative psoriasis treatments. Future long-term and well-designed studies are needed to further our knowledge regarding the cardiovascular safety profile of these agents.

Optimizing Signal Management in a Vaccine Adverse Event Reporting System: A Proof-of-Concept with COVID-19 Vaccines Using Signs, Symptoms, and Natural Language Processing

INTRODUCTION

The Vaccine Adverse Event Reporting System (VAERS) has already been challenged by an extreme increase in the number of individual case safety reports (ICSRs) after the market introduction of coronavirus disease 2019 (COVID-19) vaccines. Evidence from scientific literature suggests that when there is an extreme increase in the number of ICSRs recorded in spontaneous reporting databases (such as the VAERS), an accompanying increase in the number of disproportionality signals (sometimes referred to as 'statistical alerts') generated is expected.

OBJECTIVES

The objective of this study was to develop a natural language processing (NLP)-based approach to optimize signal management by excluding disproportionality signals related to listed adverse events following immunization (AEFIs). COVID-19 vaccines were used as a proof-of-concept.

METHODS

The VAERS was used as a data source, and the Finding Associated Concepts with Text Analysis (FACTA+) was used to extract signs and symptoms of listed AEFIs from MEDLINE for COVID-19 vaccines. Disproportionality analyses were conducted according to guidelines and recommendations provided by the US Centers for Disease Control and Prevention. By using signs and symptoms of listed AEFIs, we computed the proportion of disproportionality signals dismissed for COVID-19 vaccines using this approach. Nine NLP techniques, including Generative Pre-Trained Transformer 3.5 (GPT-3.5), were used to automatically retrieve Medical Dictionary for Regulatory Activities Preferred Terms (MedDRA PTs) from signs and symptoms extracted from FACTA+.

RESULTS

Overall, 17% of disproportionality signals for COVID-19 vaccines were dismissed as they reported signs and symptoms of listed AEFIs. Eight of nine NLP techniques used to automatically retrieve MedDRA PTs from signs and symptoms extracted from FACTA+ showed suboptimal performance. GPT-3.5 achieved an accuracy of 78% in correctly assigning MedDRA PTs.

CONCLUSION

Our approach reduced the need for manual exclusion of disproportionality signals related to listed AEFIs and may lead to better optimization of time and resources in signal management.

Serotonin syndrome: A pharmacovigilance comparative study of drugs affecting serotonin levels

BACKGROUND

Serotonin syndrome is a rare and potentially fatal adverse drug reaction caused by serotonergic drugs and is due to an increase in serotonin concentration or activation of the 5-HT receptor in the central nervous system. We analysed adverse events in the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) data set to investigate the main drug classes related to reports of serotonin syndrome and the reporting risk in relation to age and sex.

METHODS

We analysed data from the FAERS database to evaluate the main drug classes related to reports of the serotonin syndrome, and the reporting risk in relation to age and sex.

RESULTS

We found 8,997 cases of serotonin syndrome; selective serotonin reuptake inhibitors (SSRIs) was the class of drugs with most reports, followed by opioids and other antidepressants. The highest Reporting Odds Ratios (ROR) for drug classes was for monoamine oxidase (MAO) inhibitors (45.99, 95% confidence interval (CI): 41.21-51.33) and SSRIs (32.66, 95% CI: 31.33-34.04), while the ten active substances with the highest ROR were moclobemide, isocarboxazid, oxitriptane, tranylcypromine, melitracen, phenelzine, linezolid, amoxapine, reboxetine and tryptophan; with values of ROR ranging from 44.19 (95% CI: 25.38-76.94) of tryptophan to 388.36 (95% CI: 314.58-479.46) of moclobemide. The ROR for the most commonly involved drugs was higher in the group of older adults (65 > years old), and higher in males.

CONCLUSION

Prescribers need to be vigilant about drugs that can raise serotonin concentration or influence serotonergic neurotransmission, also when using drugs with less well-known risk for serotonin syndrome, like linezolid and triptans.

Detection of novel drug-adverse drug reaction signals in rheumatoid arthritis and ankylosing spondylitis: analysis of Korean real-world biologics registry data

This study aimed to detect signals of adverse drug reactions (ADRs) associated with biological disease-modifying antirheumatic drugs (DMARDs) and targeted therapies in rheumatoid arthritis (RA) and ankylosing spondylitis (AS) patients. Utilizing the KOrean College of Rheumatology BIOlogics & Targeted Therapy Registry (KOBIO) data, we calculated relative risks, excluded previously reported drug-ADR pairs, and externally validated remaining pairs using US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) and single centre's electronic health records (EHR) data. Analyzing data from 2279 RA and 1940 AS patients, we identified 35 significant drug-ADR pairs in RA and 26 in AS, previously unreported in drug labels. Among the novel drug-ADR pairs from KOBIO, 15 were also significant in the FAERS data. Additionally, 2 significant drug-laboratory abnormality pairs were found in RA using CDM MetaLAB analysis. Our findings contribute to the identification of 14 novel drug-ADR signals, expanding our understanding of potential adverse effects related to biological DMARDs and targeted therapies in RA and AS. These results emphasize the importance of ongoing pharmacovigilance for patient safety and optimal therapeutic interventions.

Association of antidepressants plus antithrombotics and bleeding risk: a pharmacovigilance study

AIM

The present study investigated the risk of bleeding when antidepressants are added to antithrombotics.

METHODS

Using data registered in VigiBase®, the WHO pharmacovigilance database, between 01/01/2000 and 31/12/2022, we compared the risk of reporting "serious" bleeding (Reporting Odds Ratio, ROR) with antidepressants + antithrombotics versus antithrombotics alone.

RESULTS

Increased values of ROR were found for the association Serotonin Reuptake Inhibitors (SRIs) + Direct Oral Anticoagulants (DOACs) versus DOACs alone (ROR=1.49(1.17-1.89)). Similar results were found for Factor Xa inhibitors or Thrombin inhibitors. This association was also found for other antithrombotics: Vitamin K Antagonists (ROR=1.37(1.12-1.68)), Platelet Aggregation Inhibitors PAIs (ROR=1.38(1.21-1.57)) and Heparins (2.04(1.59-2.62)) but not with other antidepressants (Non-Selective Monoamine Reuptake Inhibitors, NSMRIs).

CONCLUSION

The present study suggests an increased risk of "serious" bleeding when SRIs (but not NSMRIs) are associated with antithrombotics (all antithrombotics and not only DOACs).

Idiopathic intracranial hypertension secondary to fluoroquinolone therapy: French pharmacovigilance data review

We investigate spontaneous reports of IIH related to fluoroquinolones recorded in the French national pharmacovigilance database in order to detect a possible pharmacovigilance signal. The association between IIH risk and fluoroquinolone exposure was assessed using a case/non-case study. Between 1985 and July 2023, 17 reports of IIH after fluoroquinolone exposure were recorded. No specific fluoroquinolone was predominant. IIH led to death in one case and blindness in one case. The Reporting Odds Ratio was 2.58 (95% confidence interval 1.59-4.19). We highlight statistically significant disproportionality, which constitutes a pharmacovigilance signal. IIH risk after fluoroquinolone exposure is a class effect.

Disproportional signal of pericarditis with biological diseasemodifying antirheumatic drugs (bDMARDs) in patients with ankylosing spondylitis: a disproportionality analysis in the FAERS database

Objective: This study aimed to investigate the potential association between biological disease-modifying antirheumatic drugs (bDMARDs) and pericarditis and uncover relevant clinical characteristics in ankylosing spondylitis (AS). Methods: Reports of pericarditis recorded in the FDA Adverse Event Reporting System (FAERS) (January 2004-December 2022) were identified through the preferred term "pericarditis." Demographic and clinical characteristics were described, and disproportionality signals were assessed through the reporting odds ratio (ROR) and information component (IC). A significant signal was detected if the lower bound of IC (IC025) was more than zero. Results: We found 1,874 reports of pericarditis with bDMARDs (11.3% of cases with fatal outcomes). Adalimumab (IC025 3.24), infliximab (IC025 4.90), golimumab (IC025 5.40), certolizumab (IC025 5.43), etanercept (IC025 3.24), secukinumab (IC025 3.97), and ustekinumab (IC025 7.61) exhibit significant disproportionality signals compared to other medications in the FAERS database. After excluding pre-existing diseases and co-treated drugs that may increase the susceptibility of pericarditis, the disproportionality signal associated with infliximab, certolizumab, etanercept, secukinumab, and ustekinumab remained strong. Pericarditis cases associated with all bDMARDs were predominantly recorded in women aged 25-65 years. Conclusion: More reports of pericarditis were detected with AS patients on bDMARDs than with other drugs in the overall database. Further studies are warranted to investigate the underlying mechanisms and identify patient-related susceptibility factors, thus supporting timely diagnosis and safe(r) prescribing of bDMARDs.

Medication Associations With Severe Cutaneous Adverse Reactions: A Case/Non-Case Analysis Using the FDA Adverse Event Reporting System

BACKGROUND

Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) are potentially life-threatening severe cutaneous adverse reactions (SCARs). Although the classical causal agents of SCARs (antibiotics, anticonvulsants, nonsteroidal anti-inflammatory drugs, and allopurinol) are well characterized, there has been little update to this list to account for newly marketed medications.

OBJECTIVE

To provide an updated and stratified list of medications with significant reporting odds ratios (RORs) of SCARs.

METHODS

A case/non-case analysis using the United States FDA Adverse Event Reporting System was performed.

RESULTS

As expected, the prototypical medication classes made up the majority of reported cases of SJS, TEN, AGEP, and DRESS (77%, 64%, 75%, and 72%, respectively). In addition, several infrequently or previously undescribed classes/medications implicated in SCARs were identified to have significant ROR signals, including acetylcysteine, anticoagulants, diuretics, immunotherapies, proton pump inhibitors, antivirals, and antifungals. Among these reported for SJS were acetylcysteine (ROR: 64.38) and fluconazole (ROR: 17.13). For TEN, we identified furosemide (ROR: 26.32), spironolactone (ROR: 14.45), fluconazole (ROR: 30.21), amphotericin B (39.06), and acetylcysteine (ROR: 93.12). For AGEP, we identified acyclovir (ROR: 61.72), valacyclovir (ROR: 30.76), and enoxaparin (ROR: 27.37). For DRESS, we identified vemurafenib (ROR: 17.35), acyclovir (ROR: 30.63), abacavir (ROR: 26.62), raltegravir (ROR: 23.27), and valacyclovir (ROR: 21.77) to have strong reporting odds.

CONCLUSION

Our analysis provides an updated tool for physicians to reference when identifying suspected SCARs and a basis for future studies to investigate atypical medication causality.

Oral phosphodiesterase type 5 inhibitors and priapism: A VigiBase analysis

PURPOSE

To explore the differences of priapism events among a diverse cohort taking erectogenic medicines (i.e., phosphodiesterase type 5 inhibitors [PDE5i] and intracavernousal drugs).

METHODS

We queried the World Health Organization global database of individual case safety reports (VigiBase) for records of the adverse drug reactions (ADR) with sildenafil, tadalafil, avanafil, vardenafil, papaverine, and alprostadil. Disproportionality analyses (case/non-case approach) were performed to assess the reporting odds ratio (ROR) of priapism reporting in PDE5i consumers compared to intracavernousal drug recipients.

RESULTS

From a total of 133 819 ADR events for erectogenic medications, 632 were priapism (PDE5is: n = 550, 0.41%; intracavernousal drugs: n = 82, 9.92%). Priapism disproportionality signals from intracavernousal drugs were 25 times stronger than PDE5is (ROR = 34.7; confidence interval [CI] 95%: 27.12-43.94 vs. ROR = 1.38; 95% CI: 1.24-1.54). For all PDE5i agents, the 12-17 years age group had the highest ROR (9.49, 95% CI: 3.76-19.93) followed by 2-11 years (4.31, 95% CI: 1.57-9.4). Disproportionality signals for consumers under 18 for both all PDE5is as a whole (ROR = 4.57, 95% CI: 2.48-7.73) and sildenafil (ROR = 4.89, 95% CI: 2.51-8.62) were stronger than individuals 18 or older (ROR = 1.06, 95% CI: 0.93-1.21 and ROR = 1.08, 95% CI: 0.91-1.26, respectively).

CONCLUSIONS

PDE5i use shows disproportionate priapism signals which are higher in young patients.

Chronic Obstructive Pulmonary Disease Adverse Event Signals Associated with Potential Inhibitors of Glutathione Peroxidase 1: A Sequence Symmetry Analysis

BACKGROUND AND OBJECTIVE

Prior molecular modelling analysis identified several medicines as potential inhibitors of glutathione peroxidase 1 (GPx1) which may contribute to development or progression of chronic obstructive pulmonary disease (COPD). This study investigates 40 medicines (index medicines) for signals of COPD development or progression in a real-world dataset.

METHODS

Sequence symmetry analysis (SSA) was conducted using a 10% extract of Australian Pharmaceutical Benefits Scheme (PBS) claims data between January 2013 and September 2019. Patients must have been initiated on an index medicine and a medicine for COPD development or progression within 12 months of each other. Sequence ratios were calculated as the number of patients who initiated an index medicine followed by a medicine for COPD development or progression divided by the number who initiated the index medicine second. An adjusted sequence ratio (aSR) was calculated which accounted for changes in prescribing trends. Adverse drug event signals (ADEs) were identified where the aSR lower 95% confidence interval (CI) was greater than 1.

RESULTS

Twenty-one of 40 (53%) index medicines had at least one ADE signal of COPD development or progression. Signals of COPD development, as identified using initiation of tiotropium, were observed for atenolol (aSR 1.32, 95% CI 1.23-1.42) and naproxen (aSR 1.14, 95% CI 1.06-1.23). Several signals of COPD progression were observed, including initiation of fluticasone propionate/salmeterol following initiation of atenolol (aSR 1.44, 95% CI 1.30-1.60) and initiation of aclidinium/formoterol following initiation of naproxen (aSR 2.21, 95% CI 1.34-3.65).

CONCLUSION

ADE signals were generated for several potential GPx1 inhibitors; however, further validation of signals is required in large well-controlled observational studies.

Drug-induced QT prolongation and torsade de pointes: a real-world pharmacovigilance study using the FDA Adverse Event Reporting System database

Introduction: Drug-induced QT prolongation and (or) Torsade de Pointes (TdP) is a well-known serious adverse reaction (ADR) for some drugs, but the widely recognized comprehensive landscape of culprit-drug of QT prolongation and TdP is currently lacking. Aim: To identify the top drugs reported in association with QT prolongation and TdP and provide information for clinical practice. Method: We reviewed the reports related to QT prolongation and TdP in the FDA Adverse Event Reporting System (FAERS) database from January 1, 2004 to December 31, 2022, and summarized a potential causative drug list accordingly. Based on this drug list, the most frequently reported causative drugs and drug classes of QT prolongation and TdP were counted, and the disproportionality analysis for all the drugs was conducted to in detect ADR signal. Furthermore, according to the positive-negative distribution of ADR signal, we integrated the risk characteristic of QT prolongation and TdP in different drugs and drug class. Results: A total of 42,713 reports in FAERS database were considered to be associated with QT prolongation and TdP from 2004 to 2022, in which 1,088 drugs were reported as potential culprit-drugs, and the largest number of drugs belonged to antineoplastics. On the whole, furosemide was the most frequently reported drugs followed by acetylsalicylic acid, quetiapine, citalopram, metoprolol. In terms of drug classes, psycholeptics was the most frequently reported drug classes followed by psychoanaleptics, analgesics, beta blocking agents, drugs for acid related disorders. In disproportionality analysis, 612 drugs showed at least one positive ADR signals, while citalopram, ondansetron, escitalopram, loperamide, and promethazine were the drug with the maximum number of positive ADR signals. However, the positive-negative distribution of ADR signals between different drug classes showed great differences, representing the overall risk difference of different drug classes. Conclusion: Our study provided a real-world overview of QT prolongation and TdP to drugs, and the presentation of the potential culprit-drug list, the proportion of reports, the detection results of ADR signals, and the distribution characteristics of ADR signals may help understand the safety profile of drugs and optimize clinical practice.

Interstitial lung disease following COVID-19 vaccination: a disproportionality analysis using the Global Scale Pharmacovigilance Database (VigiBase)

BACKGROUND AND OBJECTIVE

Despite several case reports, population-based studies on interstitial lung disease (ILD) following COVID-19 vaccination are lacking. Given the unprecedented safety issue of COVID-19 vaccination, it is important to assess the worldwide patterns of ILD following COVID-19 vaccination. This study aimed to investigate the signals of COVID-19 vaccine-associated ILD compared with other vaccinations using disproportionality analysis.

METHODS

We analysed the VigiBase database during the period between 13 December 2020 and 26 January 2023. We adopted the case/non-case approach to assess the disproportionality signal of ILD for COVID-19 vaccines via 1:10 matching by age and sex. We compared COVID-19 vaccines with all other vaccines as the reference group.

RESULTS

Among 1 233 969 vaccine-related reports, 679 were reported for ILD. The majority of ILD cases were related to tozinameran (376 reports, 55.4%), Vaxzevria (129 reports, 19.0%) and elasomeran (78 reports, 11.5%). The reporting OR of ILD following COVID-19 vaccination was 0.86 (95% CI 0.64 to 1.15) compared with all other vaccines.

CONCLUSION

No significant signal of disproportionate reporting of ILD was observed for COVID-19 vaccines compared with all other vaccines. Moreover, when compared with the influenza vaccines that are known to cause ILD, no signal was observed. This study results might help decision-making on the subsequent COVID-19 vaccination strategy of ILD. Further large and prospective studies are required for more conclusive evidence.

Drugs and bruxism: A study in the World Health Organization's pharmacovigilance database

Bruxism is a movement disorder of uncertain aetiology. Beside local peripheral and central psychological factors, drugs were suspected. Using the World Health Organization (WHO) global pharmacovigilance database, Vigibase®, we investigated through disproportionality analyses potential associations between exposure to drugs and bruxism reports. All reports of bruxism in adults between 01/01/2000 and 31/12/2022 were included. Results are expressed as reporting odds ratio (ROR). Among the 564 reports of bruxism, an association was found with eight antidepressants (first sertraline followed by escitalopram, venlafaxine, vortioxetine, citalopram, paroxetine, fluoxetine, duloxetine) and four antipsychotics (first ziprasidone followed by aripiprazole, olanzapine, risperidone). A signal was also described for oxybate sodium and metoclopramide. For antidepressants, a negative association was found between ROR values and NET (norepinephrine transporter) but not SERT (serotonin transporter) pKi values, suggesting this ADR is more closely linked to norepinephrine than serotonin reuptake inhibition.

The Christmas adverse event syndrome: An analysis of the WHO pharmacovigilance database

OBJECTIVES

We hypothesized that during the Christmas season the safety profile and the toxicity of some drugs may be exacerbated. We therefore assessed and characterized changes in drug safety profiles over the Christmas period.

DESIGN

We performed a retrospective longitudinal analysis of adverse events reported in the World Health Organization (WHO) pharmacovigilance database between April 1st 2017 to March 31th 2023.

SETTING

We extracted cases reported by the 5 main contributors' countries of the WHO pharmacovigilance database with a Christmas tradition: USA, France, Germany, Italy and UK.

PARTICIPANTS

We analyzed 4,999,459 individual case safety reports from USA (n=3,498,961), France (n=419,018), Germany (n=398,763), Italy (n=251,641) and UK (n=431,076), reported between April 1st 2017 to March 31th 2023.

MAIN OUTCOME MEASURES

Monthly reports of adverse events were analyzed. Time trend, seasonal effect a Christmas effect (December-January) were explored.

RESULTS

We found 91 adverse events significantly more frequently reported during the Christmas period, independently after controlling for winter effect and general tendency. The main type of adverse events were psychiatric disorders, infections and skin and subcutaneous disorders. The highest numbers of attributable cases to Christmas were found for drug dependence, emotional distress, and drug withdrawal syndrome. The most involved drugs were oxycodone in psychiatric disorders (n=47,527), docetaxel in skin disorders (n=9440) and social circumstances (n=1940), olmesartan in gastrointestinal disorders (n=1263), fentanyl in cardiac disorders (n=929), adalimumab in infections (n=11,316) and immune system disorders (n=3781), and collagenase clostridium histolyticum in reproductive system disorders (n=318).

CONCLUSIONS

Our study shows that a range of drugs adverse events are more frequently reported at Christmas compared to other periods of the year, notably psychiatric disorders, infections, and skin disorders.

Thrombotic microangiopathy associated with anticancer and immune system targeting drugs: New insights from real-world data using the WHO pharmacovigilance database

BACKGROUND

The worldwide development of immune system targeting/anticancer drugs has revolutionized immuno-oncology, but their implication in thrombotic microangiopathy syndromes (TMA) is increasingly suspected. Using real-world data, the aim of this study was to identify drugs associated with TMA reporting and to describe the evolution of TMA reporting over time with a focus on these drugs.

METHODS

A global disproportionality study was performed using the individual case safety reports (ICSRs) extracted from the World Health Organization (WHO) pharmacovigilance database (VigiBase) from its inception (1968) to April 30, 2022.

RESULTS

Of the 31,251,040 ICSRs, 6946 cases of suspected drug-induced TMA were included from 55 countries. The outcome was fatal in 18.2% of cases. A total of 72 immune system targeting/anticancer drugs were associated with significant overreporting, including 17 drugs with a potential new safety concern for TMA. Although the rate of TMA reporting per million of ICSRs has remained fairly stable, an absolute increase in reported cases of suspected drug-induced TMA has been observed over the last decade. The pattern of drugs reported in TMA has evolved with a substantial increase in the proportion of cases involving immune system-targeting drugs/anticancer drugs from 47.3% (205/433) in the period 1992-2001 to 80.7% (3819/4730) in the period 2012-2021.

CONCLUSION

Several recently marketed immune system targeting/anticancer drugs have been identified as potential new drugs associated with TMA, which will require confirmatory studies. The number of drugs associated with TMA reporting markedly increased within the past 10 years, primarily due to innovative anticancer drugs.

Neurocognitive impairment in females with breast cancer treated with endocrine therapy and CDK4/6 inhibitors: a pharmacovigilance study using the World Health Organization's database

Importance: Endocrine therapies (ETs) and inhibitors of cyclin-dependent kinases-4/6 (iCDK4/6s) are a standard treatment in breast cancer. However, data on potential neurocognitive impacts remain inconsistent for ET and are scarce for iCDK4/6s. Objective: To evaluate whether ET and iCDK4/6s are associated with neurocognitive impairment (NCI). Methods: We used observational, real-world cases of NCI from the World Health Organization's database VigiBase® to perform disproportionality analysis. Cases were defined as any symptom of NCI in females treated with ETs or iCDK4/6s. The study period was from the date of the first adverse event reported in VigiBase® with iCDK4/6s (1 January 2014) until the date of data extraction (16 March 2022). In our primary analysis, we calculated the reporting odds ratio (ROR) adjusted for age to identify a potential association between NCI and individual ETs in isolation or in combination with iCDK4/6s. We also performed subgroup analyses by the NCI class. Results: We identified 2.582 and 1.943 reports of NCI associated with ETs and iCDK4/6s, respectively. NCI was significantly associated with each ET [anastrozole: n = 405, aROR = 1.52 (95% CI: 1.37-1.67); letrozole: n = 741, aROR = 1.37 (95% CI: 1.27-1.47); exemestane: n = 316, aROR = 1.37 (95% CI: 1.22-1.53); tamoxifen: n = 311, aROR = 1.25 (95% CI: 1.12-1.40); and fulvestrant: n = 319, aROR = 1.19 (95% CI: 1.06-1.33)] and only with palbociclib for iCDK4/6s [n = 1,542, aROR = 1.41 (95% CI: 1.34-1.48)]. Conclusion: These findings suggest that in females treated for breast cancer, all ETs may be associated with NCI. However, amongst iCDK4/6s, NCI may be specific to palbociclib. NCI most frequently involved learning and memory as well as language. Neurocognitive impact of treatments requires better consideration and management.

Pharmacological Evaluation of Signals of Disproportionality Reporting Related to Adverse Reactions to Antiepileptic Cannabidiol in VigiBase

Cannabidiol is the first cannabis-derived drug approved for the treatment of Lennox-Gastaut syndrome, Dravet syndrome, and Tuberous Sclerosis Complex. In the current study, we performed a descriptive analysis followed by a disproportionality analysis of potential adverse events caused by CBD extracted from the VigiBase® database. Furthermore, the biological plausibility of the association between CBD and the serotonin 5-HT1A receptor as a possible cause of adverse events was analyzed and discussed. Data were extracted from the VigiBase® database using the VigiLyze® signal detection and signal management tool. Adverse events in VigiBase® reports were coded using MedDRA, version 19 of Preferred Terms (PTs). Data were uploaded into SPSS software and analyzed via a disproportionality analysis. Statistically significant disproportionality signals for CBD were found for "weight decreased" (5.19 (95% CI: 4.54-5.70)), "hypophagia" (3.68 (95% CI: 3.22-5.27)), and "insomnia" (1.6 (95% CI: 1.40-1.83)). Positive IC025 values were found for "weight decreased" (2.2), "hypophagia" (1.3), and "insomnia" (0.5), indicating a surplus of reported cases. CBD's interactions with 5-HT1A serotonin receptors may offer a potential biological explanation for the occurrence of insomnia in patients. It is noteworthy that the risk profiles mentioned in the information for prescribing CBD as an antiepileptic agent by regulatory agencies showed disparities specifically related to the adverse event "insomnia".

Treatments During Pregnancy Targeting ERBB2 and Outcomes of Pregnant Individuals and Newborns

Importance

Targeted therapies directed against ERBB2 are the cornerstone of medical treatment for ERBB2-positive breast cancers but are contraindicated during pregnancy.

Objectives

To describe the association of exposure to anti-ERBB2 agents during pregnancy with pregnancy and fetal or newborn outcomes, and to compare the risk and types of adverse outcomes reported more frequently in this context than after exposure to other anticancer agents.

Design, Setting, and Participants

For this case-control study, All reports with a pregnancy-related condition and an antineoplastic agent (Anatomical Therapeutic Chemical classification group L01) registered in the World Health Organization international pharmacovigilance database VigiBase up to June 26, 2022, were extracted. All reports with a pregnancy, an antineoplastic treatment during pregnancy, and a cancer were retained. Reports with anticancer agents prescribed for nononcologic purposes were not included.

Exposure

The exposure group was defined as reports that mention anti-ERBB2 agents compared with exposure to other anticancer agents.

Main Outcome and Measures

The main outcome was the reporting odds ratio (ROR) for maternofetal complications in the group exposed to anti-ERBB2 agents compared with other anticancer agents, as determined using a disproportionality analysis.

Results

A total of 3558 reports (anti-ERBB2 agents, 328; other anticancer agents, 3230) were included in the analysis. In the group exposed to anti-ERBB2 agents, most reports were from the US (159 [48.5%]), the mean (SD) age of participants was 30.8 (10.4) years, and 209 patients (97.7%) were treated for breast cancers. The molecules most frequently involved in cases with anti-ERBB2 agents were trastuzumab (n = 302), pertuzumab (n = 55), trastuzumab-emtansine (n = 20), and lapatinib (n = 18). The outcomes overreported in these cases included oligohydramnios (ROR, 17.68 [95% CI, 12.26-25.52]; P < .001), congenital respiratory tract disorders (ROR, 9.98 [95% CI, 2.88-34.67]; P < .001), and neonatal kidney failure (ROR, 9.15 [95% CI, 4.62-18.12]; P < .001). Sensitivity and multivariable analyses found similar results. Toxic effects were also significantly overreported for trastuzumab-emtansine (cardiovascular malformation: ROR, 4.46 [95% CI, 1.02-19.52]) and lapatinib (intrauterine growth restriction: ROR, 7.68 [95% CI, 3.01-19.59]).

Conclusions and Relevance

In this case-control study of 328 individuals exposed to anti-ERBB2 agents during pregnancy, exposure was associated with a severe specific adverse pregnancy and fetal or newborn outcomes compared with exposure to other anticancer treatments.

Infections associated with clozapine: a pharmacovigilance study using VigiBase®

Introduction: Clozapine is primarily reserved for treatment-resistant schizophrenia due to safety concerns associated with its use. Infections have been reported with clozapine, which may lead to elevated serum levels of the drug. However, the existing literature on this topic is limited. Therefore, we conducted a study using VigiBase® to investigate the potential over-reporting of infections associated with clozapine, to explore the presence of dose-dependency, and to investigate the underlying mechanism. Methods: Disproportionality analyses were performed using VigiBase to assess the association between clozapine and all types of infections, the association between clozapine-associated infections and neutropenia, the association between clozapine-associated infections and agranulocytosis, the dose-effect relationship between clozapine and infections, and the interaction between clozapine and the main strong CYP450 inhibitors using reports carried out until 11 April 2023. Results: A statistically significant signal of infections was observed with clozapine, as indicated by an information component of 0.43 [95% CI: (0.41-0.45)]. The most commonly reported infections were respiratory and gastrointestinal in nature. Neutropenia showed weaker association with clozapine-associated reports of infections compared to other clozapine-associated reports [X2 (1, N = 204,073) = 454; p < 0.005], while agranulocytosis demonstrated a stronger association with clozapine-associated reports of infections [X2 (1, N = 204,073) = 56; p < 0.005]. No evidence of dose-dependency was observed. Among the 17 tested CYP inhibitors, significant drug-drug interactions were found with clarithromycin, metronidazole, valproic acid, lansoprazole, omeprazole, amiodarone, and esomeprazole. Discussion: Our study revealed a significant safety signal between clozapine use and infections, predominantly respiratory and gastrointestinal infections. The co-administration of clozapine with valproic acid or proton pump inhibitors may potentially contribute to an increased risk of infection. Further vigilance is warranted in clinical practice, and consideration of therapeutic drug monitoring of clozapine in cases involving concomitant use of these drugs or in the presence of infections may be beneficial.

Tumor Lysis Syndrome with CD20 Monoclonal Antibodies for Chronic Lymphocytic Leukemia: Signals from the FDA Adverse Event Reporting System

BACKGROUND AND OBJECTIVE

Although tumor lysis syndrome was reported with obinutuzumab and rituximab, the association with CD20 monoclonal antibodies for chronic lymphocytic leukemia is unclear.

METHODS

A disproportionality analysis was conducted to investigate the link between CD20 monoclonal antibodies and tumor lysis syndrome by accounting for known confounders and comparing with other anticancer drugs, using data from the US Food and Drug Administration Adverse Event Reporting System. Reporting odds ratios and the information component were calculated as disproportionality measures. A stepwise sensitivity analysis was conducted to test the robustness of disproportionality signals. Bradford Hill criteria were adopted to globally assess the potential causal relationship.

RESULTS

From 2004 to 2022, 197, 368, 41, and 14 tumor lysis syndrome reports were detected for obinutuzumab, rituximab, ofatumumab, and alemtuzumab (CD52 monoclonal antibody), respectively. Disproportionality signals were found for the above four monoclonal antibodies when compared with other anticancer drugs. Sensitivity analyses confirmed robust disproportionality signals for obinutuzumab, rituximab, and ofatumumab. The median onset time was 4.5, 1.5, and 2.5 days for rituximab, obinutuzumab, and ofatumumab, respectively. A potential causal relationship was fulfilled by assessing Bradford Hill criteria.

CONCLUSIONS

This pharmacovigilance study on the FDA Adverse Event Reporting System detected a plausible association between CD20 monoclonal antibodies (but not CD52) and tumor lysis syndrome by assessing the adapted Bradford Hill criteria. Urgent clarification of drug- and patient-related risk factors is needed through large comparative population-based studies.

Adverse reactions of PDE5 inhibitors: An analysis of the World Health Organization pharmacovigilance database

BACKGROUND

Despite their efficacy and general safety, rare but devastating adverse drug reactions have been associated with phosphodiesterase type 5 inhibitors.

OBJECTIVES

To determine the safety profile of oral phosphodiesterase type 5 inhibitors with a particular focus on priapism and malignant melanoma.

MATERIALS AND METHODS

In this case-non-case study, we queried the individual case safety reports for phosphodiesterase type 5 inhibitors within the World Health Organization global database of individual case safety reports (VigiBase) between 1983 and 2021. We included all individual case safety reports for sildenafil, tadalafil, vardenafil, and avanafil in men. For comparison, we also extracted the safety data from the Food and Drug Administration trials for these drugs. We assessed the safety profile of phosphodiesterase type 5 inhibitors by disproportionality analysis by measuring reporting odds ratio for their most commonly reported adverse drug reactions, once for all phosphodiesterase type 5 inhibitor reports and once for reports of oral phosphodiesterase type 5 inhibitor use in adult men (≥18 years old) with sexual dysfunction.

RESULTS

A total of 94,713 individual case safety reports for phosphodiesterase type 5 inhibitors were extracted. A total of 31,827 individual case safety reports were identified relating to adult men taking oral sildenafil, tadalafil, vardenafil, or avanafil for sexual dysfunction. The most common adverse drug reactions included poor drug efficacy (42.5%), headache (10.4% vs. 8.5%-27.6% [Food and Drug Administration]), abnormal vision (8.4% vs. ≤4.6% [Food and Drug Administration]), flushing (5.2% vs. 5.1%-16.5% [Food and Drug Administration]), and dyspepsia (4.2% vs. 3.4%-11.1% [Food and Drug Administration]). Priapism showed significant signals for sildenafil (reporting odds ratio = 13.81, 95% confidence interval: 11.75-16.24), tadalafil (reporting odds ratio = 14.54, 95% confidence interval: 11.56-18.06), and vardenafil (reporting odds ratio = 14.12, 95% confidence interval: 8.36-22.35). Comparing with other medications in VigiBase, sildenafil (reporting odds ratio = 8.73, 95% confidence interval: 7.63-9.99) and tadalafil (reporting odds ratio = 4.25, 95% confidence interval: 3.19-5.55) had significantly higher reporting odds ratios for malignant melanoma.

CONCLUSION

Phosphodiesterase type 5 inhibitors show significant signals correlating with priapism among a large international cohort. Further clinical study is needed to elucidate whether this is from proper or inappropriate use or other confounding conditions, as analysis of pharmacovigilance data does not allow for quantifying the clinical risk. Also, there appears to be a relationship between phosphodiesterase type 5 inhibitor use and malignant melanoma, which warrants additional study to better understand causation.

Hypoxia Associated With Dihydropyridine Calcium Channel Inhibitors: A Pharmacovigilance Study in VigiBase

Due to their negative effects on hypoxic pulmonary vasoconstriction, dihydropyridine calcium channel inhibitors (DCCIs) can lead to hypoxia in patients with a pulmonary shunt. To date, only preclinical studies and case reports have focused on this potential adverse drug reaction. We aimed to assess the reporting association between DCCIs and hypoxia using the World Health Organization pharmacovigilance database (VigiBase). We performed a disproportionality analysis to evaluate the strength of the reporting association between i.v. clevidipine and nicardipine, thought to be a surrogate of patients in the intensive care unit, and hypoxia. The information component and the lower end of its 95% credibility interval were used to evaluate disproportionality. A description of the cases was made. Secondary outcomes included the association between all DCCIs and hypoxia compared with other treatments with similar indications, urapidil and labetalol, regardless of the route of administration. Association between oral nicardipine and hypoxia was also searched. A statistically significant signal of hypoxia was found for intravenous clevidipine and nicardipine. The time to onset was reported with a median of 2 days (interquartile range 1.5-4.5). Four dechallenges were performed with intravenous nicardipine, leading to the resolution of the symptoms. Regardless of the route of administration, a signal of hypoxia was also found for nimodipine but not for other drugs, including comparators. For nicardipine no signal of hypoxia was found with the oral route of administration. Our pharmacovigilance database analysis showed a significant association between the use of intravenous DCCIs and hypoxia.

Mapping Strategies to Assess and Increase the Validity of Published Disproportionality Signals: A Meta-Research Study

BACKGROUND AND AIM

Disproportionality analysis is traditionally used in spontaneous reporting systems to generate working hypotheses about potential adverse drug reactions: the so-called disproportionality signals. We aim to map the methods used by researchers to assess and increase the validity of their published disproportionality signals.

METHODS

From a systematic literature search of published disproportionality analyses up until 1 January 2020, we randomly selected and analyzed 100 studies. We considered five domains: (1) rationale for the study, (2) design of disproportionality analyses, (3) case-by-case assessment, (4) use of complementary data sources, and (5) contextualization of the results within existing evidence.

RESULTS

Among the articles, multiple strategies were adopted to assess and enhance the results validity. The rationale, in 95 articles, was explicitly referred to the accrued evidence, mostly observational data (n = 46) and regulatory documents (n = 45). A statistical adjustment was performed in 34 studies, and specific strategies to correct for biases were implemented in 33 studies. A case-by-case assessment was complementarily performed in 35 studies, most often by investigating temporal plausibility (n = 26). Complementary data sources were used in 25 articles. In 78 articles, results were contextualized using accrued evidence from the literature and regulatory documents, the most important sources being observational (n = 45), other disproportionalities (n = 37), and case reports (n = 36).

CONCLUSIONS

This meta-research study highlighted the heterogeneity in methods and strategies used by researchers to assess the validity of disproportionality signals. Mapping these strategies is a first step towards testing their utility in different scenarios and developing guidelines for designing future disproportionality analysis.

Neonatal withdrawal syndrome following in utero exposure to antidepressants: a disproportionality analysis of VigiBase, the WHO spontaneous reporting database

BACKGROUND

Evidence on neonatal withdrawal syndrome following antidepressant intrauterine exposure is limited, particularly for antidepressants other than selective serotonin reuptake inhibitor (SSRIs).

METHODS

In our case/non-case pharmacovigilance study, based on VigiBase®, the WHO database of suspected adverse drug reactions, we estimated reporting odds ratio (ROR) and the Bayesian information component (IC) with 95% confidence/credibility intervals (CI) as measures of disproportionate reporting of antidepressant-related neonatal withdrawal syndrome. Antidepressants were first compared to all other medications, then to methadone, and finally within each class of antidepressants: SSRIs, tricyclics (TCA) and other antidepressants. Antidepressants were ranked in terms of clinical priority, based on semiquantitative score ratings. Serious v. non-serious reports were compared.

RESULTS

A total of 406 reports of neonatal withdrawal syndrome in 379 neonates related to 15 antidepressants were included. Disproportionate reporting was detected for antidepressants as a group as compared to all other drugs (ROR: 6.18, 95% CI 5.45-7.01, IC: 2.07, 95% CI 1.92-2.21). Signals were found for TCAs (10.55, 95% CI 8.02-13.88), followed by other antidepressants (ROR: 5.90, 95% CI 4.74-7.36) and SSRIs (ROR: 4.68, 95% CI 4.04-5.42). Significant disproportionality emerged for all individual antidepressants except for bupropion, whereas no disproportionality for any antidepressant was detected v. methadone. Eleven antidepressants had a moderate clinical priority score and four had a weak one. Most frequent symptoms included respiratory symptoms (n = 106), irritability/agitation (n = 75), tremor (n = 52) and feeding problems (n = 40).

CONCLUSIONS

Most antidepressants are associated with moderate signals of disproportionate reporting for neonatal withdrawal syndrome, which should be considered when prescribing an antidepressant during pregnancy, irrespective of class.

Drug-induced Sweet's syndrome: A case/non-case study in the French pharmacovigilance database

AIMS

Sweet's syndrome is an acute febrile neutrophilic dermatosis first described in 1964 by Robert Douglas Sweet. The pathophysiological mechanism is not fully established; however, several cases of Sweet's syndrome have been reported following drug administration.

METHODS

To investigate the existence of pharmacovigilance signals between drugs and the occurrence of Sweet's syndrome, we performed a case/non-case study on reports of 'acute febrile neutrophilic dermatosis' registered in the French pharmacovigilance database. Reporting odds ratio (ROR) with its 95% confidence interval were calculated.

RESULTS

Amongthe 994 789 reports recorded in the database, 136 were Sweet's syndrome, of which 50.7% were men and the median age was 59 years (range 15-91). A total of 224 drugs were mentioned as suspects: 21.0% were antibacterials, 19.2% were antineoplastics and 12.1% were immunosuppressants. Median time to onset from drug initiation to the development of Sweet's syndrome was 15 days (range 1-1095). The highest RORs were observed with bortezomib (74.04 [40.8-134.2]), azacitidine (72.14 [29.4-176.9]), perfilgrastim (67.05 [21.2-211.6]), azathioprine (55.46 [34.8-88.4]) and bendamustine (35.84 [11.4-112.8]).

CONCLUSIONS

Pharmacovigilance signals have been observed between the occurrence of Sweet's syndrome and colony-stimulating factors, immunosuppressants, antineoplastics and antibiotics. Clinicians should be aware of the potential associations with these drugs and should be encouraged to report any case of drug-induced Sweet's syndrome.