The potential role of big data in the detection of adverse drug reactions

Identifying the most at-risk age-group and longitudinal trends of drug allergy labeling amongst 7.3 million individuals in Hong Kong

BACKGROUND

Incorrect drug 'allergy' labels remain a global public health concern. Identifying regional trends of drug allergy labeling can guide appropriate public health interventions, but longitudinal or population drug allergy studies remain scarce. We analysed the serial epidemiology of drug allergy labeling to identify specific subgroups at highest risk of drug allergy labeling for potential interventions.

METHODS

Longitudinal, population-wide drug allergy labels and clinical data from over 7,337,778 individuals in Hong Kong between 2016 and 2021 were analysed.

RESULTS

The absolute prevalence and incidence of documented drug allergy were 5.61% and 277/100,000 population, respectively. Annual incidence of new allergy labels was stable between 2016 and 2019, until a significant drop in 2020 (-16.3%) during the COVID19 pandemic. The most common allergy labels were anti-infectives (245,832 [44.5%]), non-steroidal anti-inflammatory (106,843 [19.3%]), and nervous system drugs (45,802 [8.3%]). The most common labeled culprits for the most severe immediate-type (anaphylaxis) and non-immediate-type (Stevens-Johnson syndrome) reactions were beta-lactams and nervous system drugs, respectively. For individuals at highest risk of labeling, there was significantly higher incidence of overall drug and beta-lactam allergy labeling amongst individuals aged > 40 years which contributed to the majority of newly labeled allergies (377,004, 68.2%).

CONCLUSIONS

Contrary to traditional dogma, we identified disproportionately higher incidence of drug allergy labeling amongst older individuals, rather than the paediatric age group. We advocate for more population-wide drug allergy studies to investigate this phenomenon in other cohorts as well as future preventative and delabeling efforts focusing on the adult population.

Assessing intravitreal anti-VEGF drug safety using real-world data: methodological challenges in observational research

INTRODUCTION

It is generally acknowledged that the ocular safety profile of intravitreal anti-VEGF drugs is acceptable, while the burden of systemic safety of these intravitreal agents is still being debated. The evaluation of the systemic safety of these drugs using real-world data (RWD), such as spontaneous reporting systems (SRS), electronic medical records (EMRs) and claims databases has several advantages, including the capture of outcomes among real-world populations over long observation periods. Nevertheless, there is a relatively small body of research exploring the post-marketing safety of these drugs.

AREAS COVERED

The aim of this scoping review is to outline and discuss some of the methodological challenges to be faced when investigating the systemic safety of intravitreal anti-VEGF drugs using different sources of RWD.

EXPERT OPINION

Such challenges include the selection of the most suitable data source, taking into account how well drug utilization is captured and whether the outcomes and covariates of interest can be captured. The strengths and limitations of some analytic methods that can be used to quantify risk, such as the intention-to-treat approach and the as-treated approach, complement each other, and using these together provides a more balanced analysis.

Drug safety in thalassemia: lessons from the present and directions for the future

Introduction: Beta-thalassemia is an autosomal recessive hereditary anemia characterized by reduced or absent β-globin chain synthesis, affecting about 60,000 people peryear. Management for β-thalassemia major includes regular blood transfusions followed by iron chelating therapy and drug targeting ineffective erythropoiesis.Areas covered: The safety of licensed drugs for the management of β-thalassemia is reviewed, using evidence from clinical trials and observational research. Such drugs include the iron chelators and the erythrocyte maturation agent luspatercept. The safety of emerging treatment, such as hydroxyurea and thalidomide is also reviewed.Expert opinion: Beta-thalassemia is arare disease, and is not surprising that there are limited studies investigating the safety of drugs used in this disease. Indeed, although observational studies are the main source of drug safety information in areal-world setting, only eleven studies were identified for iron-chelators and none of these estimated the risk of agiven safety outcome. Future work should aim to better leverage existing sources of real-world datato investigate drug safety in thalassemia.

Frequency and Associated Costs of Anaphylaxis- and Hypersensitivity-Related Adverse Events for Intravenous Iron Products in the USA: An Analysis Using the US Food and Drug Administration Adverse Event Reporting System

Introduction and Objective

Intravenous iron preparations rapidly correct iron deficiency anemia, with the notable drug class effect of rare, yet potentially life-threatening, administration-related hypersensitivity or anaphylactic reactions. The objective of this comparative study was to assess adverse events associated with four intravenous iron preparations and estimated medical costs, in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database.

Methods

Cases of hypersensitivity reactions and anaphylaxis/anaphylactic shock associated with iron dextran, iron sucrose, ferumoxytol, and ferric carboxymaltose, spontaneously reported to FAERS (1 January, 2014 to 31 December, 2019), were extracted. The reporting odds ratio lower bound 90% confidence interval (ROR05) > 1 and cases ≥ 5 defined a likely signal for a drug–adverse event association. Adverse event-associated medical costs were estimated using Agency for Healthcare Research and Quality/Healthcare Cost and Utilization Project 2016 data.

Results

For hypersensitivity reactions, ferumoxytol and iron dextran had the highest ROR05 values (5.00 and 4.35, respectively) and greatest proportions of associated deaths (7.1% and 5.3%), followed by iron sucrose (ROR05 3.94, deaths 2.4%), and ferric carboxymaltose (ROR05 3.03, deaths 0.2%). For anaphylaxis/anaphylactic shock, ROR05 for cases/deaths were: 39.32/13.4%, ferumoxytol; 37.80/4.5%, iron dextran; 17.60/4.7%, iron sucrose; and 8.77/no deaths, ferric carboxymaltose. Downstream medical costs per adverse event were highest with iron dextran (US$8615) and ferumoxytol (US$8164), followed by iron sucrose (US$4212), and ferric carboxymaltose (US$1832).

Conclusions

Reporting rates of hypersensitivity and anaphylaxis with intravenous iron preparations were highest with ferumoxytol and lowest with ferric carboxymaltose in the US FAERS database. Adverse event-related medical costs were highest for iron dextran and ferumoxytol, and lowest for ferric carboxymaltose.

Electronic supplementary material

The online version of this article (10.1007/s40264-020-01022-2) contains supplementary material, which is available to authorized users.