Hypersensitivity reactions to biologicals: An EAACI position paper

Endotypes in Immune Mediated Drug Reactions: Present and Future of Relevant Biomarkers. An EAACI Task Force Report

Drug-induced immune reactions are an important burden for patients and health systems. They can be classified into immediate-drug hypersensitivity reactions (IDHRs) and delayed-DHRs (DDHRs) based on their phenotype. Drugs do not always behave as allergens and need to bind to proteins, forming adducts. Therefore, IDHRs can be classified as antigenic (IgE, and IgG mediated) and nonantigenic immune responses (complement activation-[CARPA], mas-related G-protein coupled receptor member X2 [MRGPRX2], cyclooxygenase [COX]-1 and cytokine release reactions [CRRs]). DDHRs are even more complex due to the different cell subsets and mechanisms involved, showing both antigenic and nonantigenic immune responses too. Since different endotypes result in similar phenotypes, the establishment of specific biomarkers is essential for an accurate diagnosis, with important relevance for the management of patients, as well as for risk stratification. The biomarkers of clinical utility are skin tests, specific IgE (sIgE), tryptase, and some HLA-DR genotyping. The diagnostic performance depends on the responsible drug. This review highlights that, unfortunately, most biomarkers have not gone beyond analytic or clinical validity. It is therefore important to set up multicentre translational studies to advance the validation process towards reaching a clinical utility phase.

Prevalence and management of immediate drug hypersensitivity observed during antineoplastic drug therapy

BACKGROUND

Immediate drug hypersensitivity reactions (IDHRs) complicate the treatment of patients with cancer. Rapid drug desensitization (RDD) is not a standard treatment option in Northern Europe as in Southern Europe and the US. Thus, in Denmark, allergists are not involved when cancer treatments are complicated by IDHRs.

PURPOSE

The purpose was to investigate whether Danish patients could benefit from the implementation of an allergy work-up including RDD by investigating the magnitude of the problem with IDHRs in Danish antineoplastic drug therapy, in addition to describe characteristics of IDHRs, re-treatment strategies, and outcomes.

PATIENTS AND METHODS

This prospective observational single-center study was conducted at a large university hospital. Patients were included over 17 months. Patients were interviewed during index reaction. Information on culprit drug, infusion procedure, and premedication was obtained, together with reaction phenotype and severity. After 3 months, information on re-treatment strategies and outcome were obtained from medical records.

RESULTS

In total, 126 patients experienced IDHRs during the study period. This corresponds to 2.5% of patients receiving antineoplastic drug therapy. Re-treatment, using increased premedication and/or decreased infusion rate, was attempted in 97 patients and tolerated by 69. However, 57 out of 126 patients (45%) discontinued treatment. This corresponds to 1.1% of patients receiving antineoplastic drug therapy. Patients with gynecologic cancers had a particularly high risk.

INTERPRETATION

IDHRs are infrequent in antineoplastic drug therapy, but due to the large number of patients with cancer, the number of IDHRs is significant. Patients discontinuing treatment could benefit from an allergy work-up including RDD.

Hereditary α-tryptasemia is associated with anaphylaxis to antibiotics and monoclonal antibodies

BACKGROUND

Hereditary α-tryptasemia, a genetic trait caused by increased α-tryptase copy number, is associated with idiopathic and venom anaphylaxis.

OBJECTIVE

We aimed to determine the impact of tryptase genotypes on drug-induced anaphylaxis.

METHODS

A prospective discovery cohort of 99 patients from a referral center in Slovenia with acute anaphylaxis to drugs underwent tryptase genotyping by droplet digital PCR. For validation, we included a cohort of 26 patients from the Czech Republic. Associated inciting agents and the severity of the reactions were subsequently examined.

RESULTS

Hereditary α-tryptasemia was associated with drug-induced anaphylaxis with a prevalence of 13% (n = 13 of 99) in the discovery cohort and 15% in the validation cohort (n = 4 of 26). Hereditary α-tryptasemia was identified in every individual with elevated basal serum tryptase levels (11.6-21.9 ng/mL; n = 14) within both cohorts of patients. Hereditary α-tryptasemia was more prevalent in individuals with antibiotic- or mAb-induced anaphylaxis in both the discovery and validation cohorts (n = 13 of 51; 26%) compared to those with anaphylaxis resulting from neuromuscular blocking agents, nonsteroidal anti-inflammatory drugs, contrast, chlorhexidine, or other drugs (n = 5 of 74; 7%; P = .02; odds ratio = 4.1; 95% CI, 1.3-11.1). Overall, we found fewer individuals with no ⍺-tryptase than in the general population, and there was a trend for subjects with more ⍺-tryptase copies to have more severe reactions. Thus, among subjects with three ⍺-tryptase copies, the prevalence of severe anaphylaxis was 73%, compared with 59% with one to two ⍺-tryptase copies and 58% for subjects without ⍺-tryptase.

CONCLUSIONS

Risk for anaphylaxis to antibiotics and biologics is associated with inherited differences in α-tryptase-encoding copies at Tryptase α/β1.

Biosimilars versus biological therapy in inflammatory bowel disease: challenges and targeting strategies using drug delivery systems

Inflammatory bowel disease (IBD) is a multifactorial illness with a climbing prevalence worldwide. While biologics are commonly prescribed especially for severe cases, they may worsen patients' outcomes due to financial burden. Consequently, there has been an increased focus on biosimilars to improve overall disease outcomes by maintaining similar efficacy and safety while minimizing the cost of therapy. Infliximab-dyyb was the first biosimilar approved by US-FDA for IBD. Since that, the US-FDA approved 14 biosimilars with different mechanisms of action and different routes of administration for IBD patients (four infliximab biosimilars, nine adalimumab biosimilars, and most recently one ustekinumab biosimilar). It should be noted that more biologics are in the pipeline as golimumab and natalizumab patents are set to expire in the near future, and biosimilars are now in pre-clinical to phase 3 trials. Different studies have evaluated biologics' effectiveness and safety and concluded that the majority of available biosimilars are efficacious and have similar adverse effect profiles compared to their reference biologics. It is worth mentioningthat post-marketing surveillance reports revealed some risks associated with biosimilars which should be taken into consideration in future research and clinical trials to avoid health hazards. Most biologics and biosimilars are administered parenterally which results in several drawbacks such as raised risk of infections, hypersensitivity, autoimmunity, development of malignancies, liver toxicity as well as worsening of heart failure. Several drug delivery systems based on passive and active targeting mechanisms are under active investigation to overcome these limitations. This review sheds light on the emergence of biologics and biosimilars as alternatives in IBD management, the differences between them, challenges and risks, and future perspectives in IBD therapy and new trends in drug delivery systems.

Successful Treatment Using Etanercept in a Patient with Enthesitis-Related Arthritis Who Had Late Allergic Reaction to Adalimumab

Background: Biological agents are considered important therapies and are increasingly used in the treatment of a range of rheumatological and inflammatory diseases. Nevertheless, the prevalent use of these treatments has been associated with increased incidence of drug-induced hypersensitivity reactions (HSR). Case Presentation: A 15-year-old patient with enthesitis-related arthritis developed late HSR after the use of adalimumab. Consequently, etanercept was used as an alternative treatment. Etanercept was administered subcutaneously through a single dose without any reaction upon examination using skin tests (skin prick test, intradermal test, and patch test) against likely cross-reactions given that both adalimumab and etanercept were anti-tumor necrosis factor (TNF) agents. Conclusions: Currently, TNF-α inhibitors find widespread use. Caution is required against HSR reactions, including systemic or local injection site reactions, although they are generally considered safe to use.

Effective desensitization in an IgE-mediated hypersensitivity reaction to tocilizumab in neuromyelitis optica

Neuromyelitis optica is a rare, inflammatory autoimmune disease of the central nervous system. Tocilizumab is a humanized monoclonal antibody, which targets the inhibition of the interleukin-6 receptor, a mediator with an important role in the pathophysiological mechanism of neuromyelitis optica. Hypersensitivity reactions to tocilizumab are rare, but similar to other biological drugs can elicit a hypersensitivity reaction. The authors present a case of a 50-year-old female patient, with a neuromyelitis optica, with a severe reaction at the 6th cycle of treatment. The patient was referred to Drug Allergy Consultation, where she underwent tocilizumab skin tests: intradermal test 1/1,000 with a positive result. The patient was then proposed for drug desensitization, and, to date, the patient has undergone 22 desensitization cycles, all of which were uneventful. This case emphasizes the importance of trying to phenotype the hypersensitivity reactions to monoclonal antibodies, and therefore invest in an allergy workup to make the best decision for our patients.

Antidrug antibodies to adalimumab do not associate with immunologically related adverse events

Introduction

Unwanted immune responses (UIRs) to biologics can negatively impact treatment efficacy and pharmacokinetics and/or induce adverse events (AEs). We characterized the UIR profile of adalimumab (ADL) using data from a phase 3, randomized, interchangeability study of reference ADL (ADL-REF; Humira®) and ADL biosimilar PF-06410293 in patients with rheumatoid arthritis (RA).

Methods

Eligible patients (18-70 years, moderate-to-severe active RA) received ADL-REF from weeks 0-10 (lead-in period) then were randomized 1:1 to: 3 switches between PF-06410293 and ADL-REF or continuous ADL-REF treatment until week 32. As interchangeability of PF-06410293 with ADL-REF was previously demonstrated, data were combined across groups to describe the development of antidrug antibodies (ADAs) and their impact on pharmacokinetics and immunologically related AEs. Pharmacokinetic endpoints included maximum observed serum concentration (Cmax), area under serum concentration-time curve over dosing interval (AUCtau), time of maximum observed serum concentration (Tmax), average serum concentration (Cav), and apparent clearance (CL/F), determined from robust pharmacokinetic sampling during weeks 30-32; and predose concentrations (Ctrough) at prespecified sampling time points. Other endpoints: patients (%) with ADA-positive and neutralizing ADA (NAb)-positive samples, time of first ADA/NAb detected, ADA titers over time, persistence of ADA/NAb, and immunologically related AEs by ADA/NAb status.

Results

Of 427 randomized patients, 59% were ADA-positive, 52% had persistent ADA, 14% were NAb-positive, and 10% had persistent NAb. In most patients, ADA/NAb first developed within 16 weeks of ADL treatment regardless of pre-existing (baseline day 1) ADA. ADA/NAb titers stabilized by week 16 without boosters. Ctrough was lower in patients with ADA-positive than ADA-negative samples throughout the study. From weeks 30-32, AUCtau, Cmax, and Cav were lower in ADA-positive than ADA-negative samples at week 30, especially in patients with ADA-positive/NAb-positive samples. Only 3% of patients had immunologically related AEs. Most were injection site and hypersensitivity reactions, and none were considered severe or serious or associated with the presence of ADA/NAb. Presence of pre-existing ADA did not increase the potential for immunologically related responses to ADL.

Conclusions

Presence of ADA (with or without NAb) was associated with lower drug concentrations and faster clearance but not with the development of immunologically related AEs.

Clinical trial registration

ClinicalTrials.gov, identifier NCT0423021.

Challenges and preventive strategies in pediatric drug hypersensitivity reactions: where do we stand?

Drug hypersensitivity reactions (DHRs) in pediatric patients present significant clinical challenges due to their potential for severe, life-threatening reactions such as anaphylaxis. Although less common than in adults, DHRs in children are more difficult to diagnose and manage due to limited pediatric-specific research. This study focuses on the role of premedication as a preventive strategy for DHRs, exploring its potential benefits and limitations. While approaches like H1-antihistamines combined with gradual drug dose escalation show promise for reducing mild histamine-mediated reactions, evidence regarding premedication's effectiveness, particularly for non-IgE-mediated mechanisms, remains inconclusive. Rapid drug desensitization (RDD) protocols demonstrate high success rates in certain cases; however, there are no strong recommendations for or against premedication, and controlled studies documenting its real efficacy are lacking. Further research is crucial to establish clear guidelines and improve the safety and outcomes of pediatric drug allergy management.

Basophil activation test is a complementary tool in the diagnosis of immediate reactions to platinum salts and taxanes

BACKGROUND

Delabelling pathways offer confirmatory diagnosis and can prevent unnecessary second-line therapies or drug desensitization procedures after chemotherapeutic hypersensitivity reactions (CHT-HSRs). However, these pathways rely on risky in vivo tests. Data on whether in vitro tests could be helpful are scarce. We assessed the role of basophil activation test (BAT) in the diagnosis of HSRs to platin salts (PSs) and taxanes (TXs) in a well-defined population featuring varied endophenotypes and severities of HSRs.

METHODS

We conducted a 3-year-long multicentric, prospective study with 121 suspected-immediate CHT-HSR patients. The allergy workup included clinical history (initial reaction based on Type I, cytokine release syndrome, and mixed phenotype's symptoms and if unable to fit in any of these, as "indeterminate"), skin testing (ST), and drug provocation testing (DPT), provided risk assessment was favorable. Final diagnosis classified patients as "hypersensitive," "non-hypersensitive," or "inconclusive." We performed BAT using CD63 and CD203c as activation markers in patients and controls. Patients underwent DPT regardless of BAT results to prevent bias.

RESULTS

ST positivity significantly correlated with skin involvement, Type I phenotype, cancer recurrence, and lifetime exposures before reactions. DPTs were negative in all indeterminate phenotype patients (p = .02) and those considered low-risk, whereas they were negative in 62% moderate-risk patients. 55% were confirmed as hypersensitive (mainly Type I reactions, p < .0001), 24% as non-hypersensitive (mainly TXs and indeterminate phenotypes), and 21% as inconclusive. BAT showed 79% sensitivity in Type I IgE-mediated reactions to PSs with a high correlation to ST.

CONCLUSIONS

BAT is a promising tool for delabelling and endotyping CHT-HSRs, especially Type I reactions to PSs, possibly identifying patients at risk of positive DPT. ST seems useful in confirming CHT-HSRs, especially PS-induced reactions, and DPT remains the gold standard, being essential even in moderate-risk patients.

Interleukin-6 as a biomarker of hypersensitivity reactions in chemotherapeutics and monoclonal antibodies

BACKGROUND

In recent years, a new type of immediate hypersensitivity reaction known as cytokine release began to emerge, and within this phenotype of reactions, interleukin-6 is the most frequently associated with the presence during drug administration. Chemotherapeutic agents (QT) and monoclonal antibodies.

OBJECTIVE

Determine interleukin-6 levels in hypersensitivity reactions to QT and monoclonal antibodies.

METHODS

Observational and prospective study that was carried out from March 1, 2021 to March 1, 2022 in a university hospital in northeastern Mexico. Symptoms, severity, interleukin-6 levels, and skin tests of hypersensitivity reaction were evaluated at QT and monoclonal antibodies.

RESULTS

A total of 41 patients with oncological disease were included, the most frequent being ovarian cancer. Symptoms as initial hypersensitivity reaction were neuromuscular in taxanes and cutaneous in Platinums.41.5% presented elevation of interleukin-6, and it was found more frequently in presence of metastases. Positive skin tests were found more frequently in the carboplatin and doxorubicin groups. The most frequently presented phenotype was type I in paclitaxel, carboplatin, and doxorubicin, and mixed-reaction (type I and cytokine release) in oxaliplatin.

CONCLUSION

With the increasing prevalence of hypersensitivity reactions to biologic and antineoplastic therapies, interleukin-6 should be recognized as a biomarker in immediate hypersensitivity reactions to QT and monoclonal antibodies.

Factors Associated With Infusion Reactions in Patients With Breast Cancer Receiving Trastuzumab

Background/Aim

Trastuzumab (TRA) is a key drug in human epidermal growth factor receptor type 2 (HER2)-positive breast cancer treatment. Infusion reactions (IR) with TRA are frequently observed in practice. Although the efficacy of premedication has been previously reported, it remains uncommon. The probability of severe IR due to TRA is low; however, when it does occur, it is associated with patient discomfort and expenditure of medical resources. This study aimed to analyze the factors associated with the occurrence of IR in patients with breast cancer who received TRA.

Patients and Methods

We retrospectively studied 204 patients who underwent TRA for breast cancer treatment between September 2008 and June 2023, identifying factors influencing the occurrence of IR at the time of TRA administration.

Results

A total of 182 patients were included in this study, and the incidence of IR was 25.8% (47/182 patients). Multiple logistic regression analysis showed that pertuzumab (PER) use, high alkaline phosphatase (ALP), and low high-density lipoprotein (HDL) cholesterol levels were associated with IR.

Conclusion

IR should be considered when PER is combined with TRA. ALP and HDL cholesterol levels may be predictive markers of TRA-induced IR in patients with breast cancer.

Retrospective analysis of rapid drug desensitization with biologic agents: A single center experience

BACKGROUND

Following the increased use of biological agents, a subset of patients experiences hypersensitivity reaction (HSR). We reported our experience with rapid drug desensitization (RDD) to nine biologics (rituximab, infliximab, cetuximab, trastuzumab, pertuzumab, nivolumab, brentuximab, tocilizumab and filgrastim) and identified risk factors for breakthrough reactions (BTRs).

METHOD

This was a retrospective review (2013-2022) of patients with immediate HSRs to biological agents. Initial HSRs were classified as grade 1, 2, or 3 in their severity. Skin prick tests (SPT)/intradermal tests (IDT) were performed using implicated agents. The phenotypes of HSRs were defined as Type I, cytokine-release syndrome (CRS), mixed reactions (cytokine-release + type I) based on history, clinical presentations and skin tests with implicated biologicals. A 12-step RDD protocol was used.

RESULTS

The study comprised 45 patients (F/M: 31/14, median age: 55 (range: 20-69)). Majority of the patients reacted at the first infusion (n: 29/45, 64.4%). The majority of initial HSRs were grade 3 (n: 24/45, 53.3%) and grade 2 (n: 21/45, 46.6%); none were grade 1. Initial reactions were presented as type I (n: 20/45, 44.4%), CRS (n: 12/45, 26.6%) and mixed (n: 13/45, 28.8%). A total of 258 RDDs were performed and 98.4% of them were completed successfully. BTRs occurred in 36/258 (13.9%) infusions of RDDs. There was no significant association between the BTRs and age, drug cycle, SPT and IDT positivity, gender, comorbidities, or atopy.

CONCLUSION

In our experience, 98.4% of 258 RDDs to biologics were successfully completed; RDD was safe and effective for our population.

Immediate Hypersensitivity Reactions to Biologic Drugs in Children with Inflammatory Bowel Diseases

INTRODUCTION

The increased use of biologic drugs (BDs) may lead to an increase in immediate hypersensitivity reactions (I-HSRs) in pediatric patients with inflammatory bowel disease (IBD). Our aim was to assess I-HSRs to BDs in pediatric IBD, examining frequency, clinical features, management, and associated risk factors.

METHODS

All children diagnosed with IBD at our institution between January 1, 2006, and August 1, 2023, and who developed I-HSRs related to any BD were included in the study.

RESULTS

In a study of 197 pediatric IBD patients, 61 used BD. Among these, 52.4% were male, with a median diagnosis age of 145 months (13-215). Out of a total of 1,679 administrations, 6 patients developed I-HSRs (5 with infliximab, 1 with adalimumab), resulting in a frequency of 9.8% per patient and 0.36% per administration. Of these, 66.7% were cases of Type 1 HSRs (skin test positivity n = 1), while the rest were infusion-related reactions (anti-drug antibody positivity n = 4), all of which were mild to moderate in severity. In the age and gender-adjusted logistic regression model, the presence of any comorbid allergic disease was significantly associated with the occurrence of I-HSR (aOR = 8.35; 95% CI = 1.24-56.38; p = 0.029).

CONCLUSION

The frequency of I-HSRs to BDs in children with IBD is not rare but not severe in the long term. The presence of any comorbid allergic disease is a risk factor for the development of I-HSRs to BDs.

Single center experience with more than 600 drug desensitization in Colombia

Background

Drug hypersensitivity reactions (DHRs) have a significant impact on both, patient and their treating physicians; it is considered a public health concern. The history of allergy to drugs, limits therapeutic options and will lead to the use of more expensive and potentially less effective options. Drug desensitization (DD) is considered as a procedure with a positive impact on the prognosis of the patient's disease. The objective of this study is to describe the experience with a substantial number of drugs desensitization in a fourth level center in Cali, Colombia.

Methods

An observational, cross-sectional and descriptive study was conducted. Patients with DHRs who underwent a standardized institutional DD protocol, between March of 2012 and May of 2023, were included.

Results

Two hundred forty-one patients were included. The median age was 47.8 years (4-88). One hundred fifty-six (64.7%) were women, including three who were pregnant. A total of 641 DDs were performed. The most frequent groups of drugs for which the desensitization was performed were monoclonal antibodies in 83 patients (34.4%), chemotherapeutic agents in 53 (21.6%), NSAIDs in 44 (18.2%), and antibiotics in 42 (17.4%). Eighty-seven patients (36.1%) experienced hypersensitivity to the culprit drug on first exposure, while 154 (63.9%) exhibited reactions during subsequent cycles. The main clinical presentation that gave rise to desensitization was anaphylaxis in 125 patients (51.8%), followed by cutaneous symptoms in 106 patients (44%). The predominant observed endophenotype was type 1 in 188 patients (78.3%), followed by mixed type in 46 patients (19.2%). Breakthrough reactions were observed in 50 patients (20.7%). Tolerance to DD was achieved in 636 of the procedures (99.2%), allowing the continuity of treatment of choice for the underlying disease.

Conclusions

Most desensitized patients were women with type I reactions. Monoclonal antibodies were the most frequent culprit drugs. DD in patients with DHRs is a useful, safe and effective procedure. The administration of the implicated drug had a positive impact on the course of the disease in these patients.

Dermatologische unerwünschte Arzneimittelwirkungen bei Behandlung mit Biologika – Pathogenese und Management

Biologika sind für verschiedene Entzündungskrankheiten aus Dermatologie, Allergologie, Rheumatologie und Gastroenterologie sowie für zahlreiche maligne Erkrankungen zugelassen. Dermatologische unerwünschte Arzneimittelwirkungen durch Biologika können primären entzündlichen Dermatosen ähneln, unterscheiden sich von ihnen jedoch in ihrer Pathogenese. In diesem Artikel beschreiben wir die fünf verschiedenen Pathomechanismen dermatologischer, unerwünschter Arzneimittelwirkungen durch Biologika. Durch besseres Verständnis dieser Mechanismen erhoffen wir uns wertvolle Einblicke in die Pathogenese primärer Entzündungskrankheiten zu gewinnen. Außerdem geben wir in diesem Artikel Empfehlungen für die Behandlung und das Management der durch Biologika ausgelösten dermatologischen unerwünschten Arzneimittelwirkungen.

Dermatologic adverse events caused by biologic treatments - Pathogenesis and management

Biologics are approved for various dermatologic, allergic, rheumatic, and gastroenterologic inflammatory diseases, as well as for numerous malignancies. The dermatologic adverse events from treatment with biologics may resemble primary inflammatory diseases but differ in pathogenesis. In this article, we describe five different pathogenic mechanisms of dermatologic adverse events. By studying these mechanisms, we hope to gain valuable insights into the pathogenesis of primary inflammatory diseases. In addition, in this article, we provide recommendations for the treatment and management of the dermatological adverse events induced by biologics.

Real-World Safety Profile of Biologic Drugs for Severe Uncontrolled Asthma: A Descriptive Analysis from the Spanish Pharmacovigilance Database

Background: The present investigation provides a thorough analysis of adverse drug reactions (ADRs) reported in the Database of the Spanish Pharmacovigilance System (FEDRA) for biologic medications primarily indicated for severe refractory asthma, including omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, and tezepelumab. Our main objective was to identify ADRs not documented in the drugs' Technical Sheets (summary of product characteristics, SmPC), potentially indicating unrecognized risks meriting pharmacovigilance attention. Methods: Data spanning from each drug's market introduction until 22 January 2024, were analyzed, sourced from direct submissions to the Spanish Pharmacovigilance System, industry communications, and literature reviews. We evaluated notifications impartially to ensure a comprehensive review of all the ADRs associated with these medications. Results: This investigation underlines the critical role of post-marketing surveillance in enhancing patient safety. It emphasizes the necessity for healthcare professionals to report ADRs comprehensively to foster a robust pharmacovigilance system. Furthermore, the study highlights gaps between the reported ADRs and the information provided in SmPCs, signaling potential areas for improvement in drug safety monitoring and regulatory oversight. Conclusions: Finally, these findings may contribute to informed decision making in clinical practice and regulatory policy, ultimately advancing patient care and safety in the management of severe uncontrolled asthma.

Basophil Activation Test Predicts Cetuximab Anaphylaxis Severity in Alpha-Gal IgE-Positive Patients

Upon first exposure to cetuximab, hypersensitivity reactions can occur. We aimed to assess the utility of the basophil activation test (BAT) to alpha-gal and cetuximab for predicting severe reactions. We prospectively recruited 38 patients and evaluated sIgE to alpha-gal in all patients before the first application of cetuximab. In all alpha-gal-sensitized patients, we evaluated skin tests to meat extracts, gelatine, and cetuximab and performed BAT with alpha-gal and cetuximab. In 24% (9/38) of patients, sIgE to alpha-gal was >0.10 kUA/L, and 8/9 reacted to the cetuximab. Basophil activation tests with alpha-gal were positive in all sensitized patients and were higher in those with severe reactions (18.3% in grade 4 [n = 4] vs. 1.8% in grade 2 [n = 3] or no reaction [n = 1] at 3.3 ng/mL of alpha-gal; p = 0.03). All patients with severe grade 4 reactions had a positive CD63 BAT response to cetuximab compared to patients with moderate or no reaction, who all had negative BAT (57.7% vs. 0.9% at 500 µg/mL, 63.2% vs. 4.1% at 100 µg/mL, 58.2% vs. 2.7% at 10 µg/mL, and 32.1% vs. 3.3% at 1 µg/mL of cetuximab, respectively; p ≤ 0.001). In summary, before initiating cetuximab treatment, sIgE to alpha-gal should be assessed in all patients. To predict the severity of the reaction and to assess the risk of cetuximab-induced anaphylaxis, we should perform BATs with alpha-gal or more discriminative BATs with cetuximab.

Hypersensitivity reactions to anticancer chemotherapy and monoclonal antibodies: Safety and efficacy of desensitization

BACKGROUND

Hypersensitivity reactions to anticancer chemotherapy and monoclonal antibodies may lead to discontinuation of first-line treatment options. Identification of these reactions can provide specific diagnosis and treatment by rapid drug desensitizations.

OBJECTIVE

To determine the hypersensitivity reactions involved in anticancer chemotherapy and monoclonal antibodies, and the safety and efficacy of rapid drug desensitization.

METHODS

We conducted an observational study of hypersensitivity reaction presented after the administration of anticancer chemotherapy and monoclonal antibodies in Mexico. We documented the symptoms of initial reaction and their severity, and the results of skin tests. We also report our experience of the administration of 12-step (mild-moderate reactions) and 16-step (severe reactions) desensitization protocols in these patients.

RESULTS

Overall, 93 patients received 336 rapid drug desensitization; 105 to taxanes, 115 to platinum drugs, 101 to monoclonal antibodies, and 15 other anticancer chemotherapy. Hypersensitivity reaction to taxanes occurred in the first or second administration, platinum drugs after the sixth cycle, and rituximab in the first cycle. The most common symptom in carboplatin was urticaria, paclitaxel back pain, oxaliplatin and docetaxel dyspnea, and in the monoclonal antibodies cardiovascular symptoms. Skin tests were positive in 75% of the carboplatin group, and only 16.7% in docetaxel. There was a rapid drug desensitization success rate of 99.4% and 85.7% did not present any related hypersensitivity reaction.

CONCLUSION

The diagnosis of hypersensitivity reaction to anticancer chemotherapy and monoclonal antibodies offers a panorama in the management of oncological diseases. Our standardized desensitization protocol is safe and effective and can be reproduced in other centers to treat patients who need to maintain first-line treatment.

Biomarkers of immediate drug hypersensitivity

Immediate drug hypersensitivity reactions (IDHRs) are a burden for patients and the health systems. This problem increases when taking into account that only a small proportion of patients initially labelled as allergic are finally confirmed after an allergological workup. The diverse nature of drugs involved will imply different interactions with the immunological system. Therefore, IDHRs can be produced by a wide array of mechanisms mediated by the drug interaction with specific antibodies or directly on effector target cells. These heterogeneous mechanisms imply an enhanced complexity for an accurate diagnosis and the identification of the phenotype and endotype at early stages of the reaction is of vital importance. Currently, several endophenotypic categories (type I IgE/non-IgE, cytokine release, Mast-related G-protein coupled receptor X2 (MRGPRX2) or Cyclooxygenase-1 (COX-1) inhibition and their associated biomarkers have been proposed. A precise knowledge of endotypes will permit to discriminate patients within the same phenotype, which is crucial in order to personalise diagnosis, future treatment and prevention to improve the patient's quality of life.

EAACI/ENDA position paper on drug provocation testing

In drug hypersensitivity, drug provocation testing (DPT), also called drug challenge, is the gold standard for investigation. In recent years, risk stratification has become an important tool for adjusting the diagnostic strategy to the perceived risk, whilst still maintaining a high level of safety for the patient. Skin tests are recommended before DPT but may be omitted in low-risk patients. The task force suggests a strict definition of such low-risk patients in children and adults. Based on experience and evidence from studies of allergy to beta-lactam antibiotics, an algorithm on how to adjust DPT to the risk, and when to omit skin tests before DPT, is presented. For other antibiotics, non-steroidal anti-inflammatory drugs and other drugs, skin tests are poorly validated and DPT is frequently necessary. We recommend performing DPT with chemotherapeutics and biologicals to avoid unnecessary desensitization procedures and DPT with skin tests negative contrast media. We suggest DPT with anesthetics only in highly specialized centers. Specifics of DPT to proton pump inhibitors, anticonvulsants and corticosteroids are discussed. This position paper provides general recommendations and guidance on optimizing use of DPT, whilst balancing benefits with patient safety and optimizing the use of the limited available resources.

Hypersensitivity reactions to nonsteroidal anti-inflammatory drugs in adults: Beyond current classification

BACKGROUND

Hypersensitivity reactions (HSRs) to nonsteroidal anti-inflammatory drugs (NSAIDs) are a significant clinical issue. Several classifications have been proposed to categorize these reactions, including the current European Academy of Allergy and Clinical Immunology/European Network for Drug Allergy (EAACI/ENDA) classification. This study aimed to evaluate the applicability of this classification in a real-world clinical setting.

METHODS

We conducted a national multicenter study involving patients from nine hospitals in four major urban centers in Turkey. All patients had a suggestive clinical history of hypersensitivity reactions to NSAIDs. Researchers collected data using a structured form and classified reactions based on the EAACI/ENDA classification. Oral provocation tests with several NSAIDs were performed using a single-blind challenge per EAACI/ENDA guidelines.

RESULTS

Our retrospective study included 966 adult patients with a history of hypersensitivity to NSAIDs. The most common triggers were Acetylsalicylic Acid (ASA), paracetamol, and metamizole. The most prevalent acute NSAID hypersensitivity group was NSAID-induced urticaria/angioedema (NIUA) (34.3%). However, 17.3% of patients did not fit neatly into the current EAACI/ENDA classification. Notably, patients with underlying asthma or allergic rhinoconjunctivitis exhibited unusual reactions, such as urticaria and/or angioedema induced by multiple chemical groups of NSAIDs, blended mixed reactions, and isolated periorbital angioedema in response to multiple chemical groups of NSAIDs.

CONCLUSIONS

While the EAACI/ENDA classification system stratifies NSAID-induced hypersensitivity reactions into five distinct endotypes or phenotypes, it may not fully capture the diversity of these reactions. Our findings suggest a need for further research to refine this classification system and better accommodate patients with atypical presentations.

Hypersensitivity reactions to biologics used in the treatment of allergic diseases: clinical features, diagnosis and management

Several monoclonal antibodies have been approved by the Food and Drug Administration (FDA) to treat allergic disorders, including omalizumab, dupilumab, mepolizumab, reslizumab, benralizumab, tralokinumab and tezepelumab, and their indications continue to expand. Although the risks associated with these agents are overall low, hypersensitivity reactions have been described and are reported more frequently with increased use. We provide a comprehensive review of clinical features, diagnosis and management of hypersensitivity reactions attributed to these agents. We aim to provide useful information for the clinician managing hypersensitivity reactions to these monoclonal antibodies, as well as highlight the need for future research to address specific gaps in knowledge.

Tools for Etiologic Diagnosis of Drug-Induced Allergic Conditions

Drug hypersensitivity reactions are a serious concern in clinical practice because they can be severe and result in lifelong sequelae. An accurate diagnosis and identification of the culprit drug is essential to prevent future reactions as well as for the identification of safe treatment alternatives. Nonetheless, the diagnosis can be challenging. In vivo and in vitro tests can be helpful, although none are conclusive; therefore, the tests are not usually performed in isolation but as part of a diagnostic algorithm. In addition, some in vitro tests are only available in research laboratories, and standardization has not been fully accomplished. Collaborating research is needed to improve drug hypersensitivity reaction diagnosis. In this review, we update the current available in vivo and in vitro tools with their pros and cons and propose an algorithm to integrate them into clinical practice.

Immune Reactions in Major Types of Oncological Treatment

In recent years, there has been a noticeable development in oncological treatment, including chemotherapy and biological treatment. Despite their significant effectiveness, they are not free from side effects, such as allergic and dermatological reactions. These reactions can vary in severity and outcome, including potential death. Examples, among others, are type I-IV hypersensitivity reactions of various origins and skin reactions including rashes, itching and redness, but also severe cutaneous syndromes. Due to the therapy used, these may include Stevens-Johnson syndrome, toxic epidermal necrolysis, drug rash with eosinophilia and systemic symptoms, drug-induced hypersensitivity syndrome and acute generalized exanthematous pustulosis. In some cases, it is necessary to interrupt therapy, which may result in a poorer outcome and shorten the patient's survival. This paper reviews various types of research documents published since 2016. It aims to systematize the latest knowledge and highlight the need for further research into ways to avoid adverse reactions.

Innovative Metrics for Reporting and Comparing the Glycan Structural Profile in Biotherapeutics

Glycosylation is a critical quality attribute in biotherapeutics, impacting properties such as protein stability, solubility, clearance rate, efficacy, immunogenicity, and safety. Due to the heterogenic and complex nature of protein glycosylation, comprehensive characterization is demanding. Moreover, the lack of standardized metrics for evaluating and comparing glycosylation profiles hinders comparability studies and the establishment of manufacturing control strategies. To address both challenges, we propose a standardized approach based on novel metrics for a comprehensive glycosylation fingerprint which greatly facilitates the reporting and objective comparison of glycosylation profiles. The analytical workflow is based on a liquid chromatography-mass spectrometry-based multi-attribute method. Based on the analytical data, a matrix of glycosylation-related quality attributes, both at site-specific and whole molecule level, are computed, which provide metrics for a comprehensive product glycosylation fingerprint. Two case studies illustrate the applicability of the proposed indices as a standardized and versatile approach for reporting all dimensions of the glycosylation profile. The proposed approach further facilitates the assessments of risks associated with changes in the glycosylation profile that may affect efficacy, clearance, and immunogenicity.

Successful adalimumab graded challenge after allergic delayed reaction to golimumab in a woman with rheumatoid arthritis

A graded challenge with adalimumab could be safe in case of a delayed allergic reaction to golimumab, after a detailed allergological evaluation and the exclusion of allergic sensitization using skin tests.

A graded challenge with adalimumab could be safe in case of a delayed allergic reaction to golimumab, after a detailed allergological evaluation and the exclusion of allergic sensitization using skin tests.

Interleukin-6 and cytokine release syndrome: A new understanding in drug hypersensitivity reactions

Immediate drug hypersensitivity reactions (DHRs) are historically thought to be because of immunoglobulin E (IgE) cross-linking, causing mast cell degranulation and release of mediators like tryptase and histamine. With the increasing use of monoclonal antibodies, it has become apparent that some patients present atypical features during immediate DHRs, including occurrence in initial exposure, a lack of urticaria and angioedema, and the presence of fever, chills, rigors and musculoskeletal pain as the predominant symptoms. This observation led to the recognition of a novel phenotype of immediate DHRs called cytokine release syndrome (CRS). Other types of immediate DHRs include infusion-related reactions (which present similarly to CRS), and mixed reactions (which share overlapping features of both type 1 reactions and CRS). Desensitization to culprit drugs can be a lifesaving option in patients who develop immediate DHRs to first-line treatment. Whereas robust data are supporting the safety and efficacy of drug desensitization, breakthrough reactions can still occur and CRS seems to be a more common cause than type 1 reactions. Tryptase has been the only available biomarker for immediate DHRs and is associated with type 1 reactions. Emerging evidence consistently found the association between increased serum interleukin 6 level and DHR-related CRS, suggesting that interleukin 6 can be a novel biomarker, in addition to tryptase, to distinguish various types of DHRs. In the era of precision medicine, phenotyping and endotyping hypersensitivity reactions to chemotherapy and monoclonal antibodies using validated biomarkers should be part of routine drug allergy care.

Hypersensitivity reactions to biologics in children

INTRODUCTION

Hypersensitivity reactions (HSRs) have been observed with the use of biologics in children. The management of HSRs in children is mainly based on experiences from the adult population. Recently, data from different centers experienced in managing these reactions, including desensitization in children, have been published, allowing clinicians to have an appropriate global overview and compare results.

AREAS COVERED

This review highlights the published data on hypersensitivity reactions to biologics in children and drug desensitization protocols adapted to the pediatric population.

EXPERT OPINION

With regard to HSRs to biologics in children, few data are available. Compared with the adult population, there is a lack of knowledge in the endophenotypes, management and the standardization of protocols including premedication regimens in children. An international consensus is needed to provide clinicians with new insight on how to apply personalized management and to perform tailored desensitization protocols in pediatric populations. Various specialists including allergists, pediatricians, oncologists, hematologists, rheumatologists, and pharmacists, should build a multidisciplinary management team to keep pediatric patients on their best treatment options in the safest manner.

Hypersensitivity to Biological Treatments in Juvenile Idiopathic Arthritis: How Should It Be Managed?

Juvenile idiopathic arthritis (JIA) is one of the most frequent diseases in the practice of pediatric rheumatology. JIA treatments have been modified and improved with the use of biological drugs along with technological innovations. However, different types of hypersensitivity reactions to biological drugs have also been reported. Anaphylaxis and infusion reactions occurring during the intravenous infusion require a critical approach in the acute period. On the other hand, the detection of drug-related late-type reactions and the development of antibodies to the agent highlight the need for an understanding of the drug-induced etiology to prevent the patient from continuing the treatment with the culprit drug. The chronic disease process, concomitant immune dysregulation, and multiple drug use may result in these hypersensitivity reactions. In this review, the hypersensitivity reactions to the biological treatments used in patients with juvenile idiopathic arthritis and the management of these conditions are discussed.

A Review of Adverse Reactions to Biologics Used in Allergy-Immunology Practice

Biologic agents have become an integral therapeutic option for practicing allergists-immunologists for the management of asthma, atopic dermatitis, chronic rhinosinusitis with nasal polyps, and various immunologic conditions. As these agents vary considerably from traditional small-molecule drugs, various adverse reactions have been noted. A different approach must be used to classify these reactions beyond the classic Gell-Coombs classification system as it does not capture many of the adverse events seen with biologic therapy. This article addresses the available literature on proposed classification systems and diagnostic modalities for adverse events associated with biologics and reviews each approved agent used frequently in allergy-immunology practice.

Validity of Diagnostic Algorithms for Inflammatory Bowel Disease in Japanese Hospital Claims Data

Inflammatory bowel disease (IBD) diagnoses are increasing in Japan. Some patients have symptoms that are difficult to control, and further research on IBD is needed. Claims databases, which have a large sample size, can be useful for IBD research. However, it is unclear whether the International Classification of Diseases, Tenth Revision (ICD-10) codes alone can correctly identify IBD. We aimed to develop algorithms to identify IBD in claims databases. We used claims data from the Department of Gastroenterology, Tohoku University Hospital from 1 January 2016 to 31 December 2020. We developed 11 algorithms by combining the ICD-10 code, prescription drug, and workup information. We had access to the database which contains all the information for Crohn’s disease and ulcerative colitis patients who visited our department, and we used it as the gold standard. We calculated sensitivity, specificity, positive predictive value (PPV), and negative predictive value for each algorithm. We enrolled 19,384 patients, and among them, 1012 IBD patients were identified in the gold standard database. Among 11 algorithms, Algorithm 4 (ICD-10 code and ≥1 prescription drugs) showed a strong performance (PPV, 94.8%; sensitivity, 75.6%). The combination of an ICD-10 code and prescription drugs may be useful for identifying IBD among claims data.

Standards for practical intravenous rapid drug desensitization & delabeling: A WAO committee statement

Drug hypersensitivity reactions (DHRs) to intravenous drugs can be severe and might leave patients and doctors in a difficult position where an essential treatment or intervention has to be suspended. Even if virtually any intravenous medication can potentially trigger a life-threatening DHR, chemotherapeutics, biologics, and antibiotics are amongst the intravenous drugs most frequently involved in these reactions. Admittedly, suspending such treatments may negatively impact the survival outcomes or the quality of life of affected patients. Delabeling pathways and rapid drug desensitization (RDD) can help reactive patients stay on first-choice therapies instead of turning to less efficacious, less cost-effective, or more toxic alternatives. However, these are high-complexity and high-risk techniques, which usually need expert teams and allergy-specific techniques (skin testing, in vitro testing, drug provocation testing) to ensure safety, an accurate diagnosis, and personalized management. Unfortunately, there are significant inequalities within and among countries in access to allergy departments with the necessary expertise and resources to offer these techniques and tackle these DHRs optimally. The main objective of this consensus document is to create a great benefit for patients worldwide by aiding allergists to expand the scope of their practice and support them with evidence, data, and experience from leading groups from around the globe. This statement of the Drug Hypersensitivity Committee of the World Allergy Organization (WAO) aims to be a comprehensive practical guide on the technical aspects of implementing acute-onset intravenous hypersensitivity delabeling and RDD for a wide range of drugs. Thus, the manuscript does not only focus on clinical pathways. Instead, it also provides guidance on topics usually left unaddressed, namely, internal validation, continuous quality improvement, creating a healthy multidisciplinary environment, and redesigning care (including a specific supplemental section on a real-life example of how to design a dedicated space that can combine basic and complex diagnostic and therapeutic techniques in allergy).

Drug allergy desensitization is not a unique recipe

PURPOSE OF REVIEW

Drug desensitization is the only therapeutic option for patients with drug allergies who need to receive the drugs they are allergic to, and it is especially critical in patients with an urgent need for chemotherapy, biologics, or antibiotics, where equally effective alternatives might not be available. However, drug desensitization is not a cookbook where anyone with no experience or specific training can find a general recipe. This review article will approach the singularities that make personalized and highly specialized care essential in this field.

RECENT FINDINGS

Drug desensitization needs to be personalized for each individual patient bearing in mind countless factors. Recent articles have tried to define the optimal resources and the most important factors to account for in personalization. However, drug desensitization is only a tool within the wider management pathway, and we will discuss recent findings in allergy delabelling in chemotherapy, biologics, and antibiotics.

SUMMARY

Risk-assessment, delabelling, and desensitization protocols, as a part of wider management pathways, can be adapted locally along with comprehensive and multifactorial risk-management strategies. These high-complexity and high-risk procedures, such as drug desensitization, need to be managed by expert allergists who can provide personalization, innovation, continuous improvement, research, and teaching in expert centres.

Cytokine Release Syndrome in Cancer Patients Receiving Immune Checkpoint Inhibitors: A Case Series of 25 Patients and Review of the Literature

Cytokine release syndrome (CRS) is a phenomenon of immune hyperactivation described in the setting of immunotherapy. Unlike other immune-related adverse events, CRS triggered by immune checkpoint inhibitors (ICIs) is not well described. The clinical characteristics and course of 25 patients with ICI-induced CRS from 2 tertiary hospitals were abstracted retrospectively from the medical records and analyzed. CRS events were confirmed by 2 independent reviewers and graded using the Lee et al. scale. The median duration of CRS was 15.0 days (Q1; Q3 6.3; 29.8) and 10 (40.0%) had multiple episodes of CRS flares. Comparing the clinical factors and biomarkers in Grades 1-2 and 3-5 CRS, we found that patients with Grades 3-5 CRS had following: (i) had longer time to fever onset [25.0 days (Q1; Q3 13.0; 136.5) vs. 3.0 days (Q1; Q3 0.0; 18.0), p=0.027]; (ii) more cardiovascular (p=0.002), neurologic (p=0.001), pulmonary (p=0.044) and rheumatic (p=0.037) involvement; (iii) lower platelet count (p=0.041) and higher urea (p=0.041) at presentation compared to patients with Grades 1-2 CRS. 7 patients (28.0%) with Grades 1-2 CRS were rechallenged using ICIs without event. 9 patients (36.0%) were treated with pulse methylprednisolone and 6 patients (24.0%) were treated with tocilizumab. Despite this, 3 patients (50%) who received tocilizumab had fatal (Grade 5) outcomes from ICI-induced CRS. Longer time to fever onset, lower platelet count and higher urea at presentation were associated with Grade 3-5 CRS. These parameters may be used to predict which patients are likely to develop severe CRS.

Adverse Reactions to Biologic Medications Used in Allergy and Immunology Diseases

PURPOSE OF REVIEW

The use of biologic therapies has risen exponentially over recent years, allowing for unprecedented disease control within numerous areas of Allergy/Immunology. With this expanded use, awareness and understanding of adverse reactions to biologic agents have also increased.

RECENT FINDINGS

Multiple biologic adverse reaction phenotypes have been described, but significant overlap in clinical features across phenotypes exists. Given considerable phenotypic overlap, a targeted testing approach may not always be clear, and more recent classifications focus on management decision making using tools of diagnostic challenges and rapid drug desensitizations, guiding clinicians in developing a management plan when the exact underlying mechanism is not clearly known. With increased clinical experience with omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, tezepelumab, rituximab, and TNF-inhibitors, there is a growing appreciation to the spectrum and particularities of adverse reactions to these agents which are outlined in this review. Our understanding of the clinical presentation and management of adverse reactions to biologic medications encountered in Allergy/Immunology has grown. Opportunities remain to further define optimal diagnostic and management strategies for these reactions.

How to Prevent and Mitigate Hypersensitivity Reactions to Biologicals Induced by Anti-Drug Antibodies?

Biologicals are widely used therapeutic agents for rheumatologic diseases, cancers, and other chronic inflammatory diseases. They are characterized by complex structures and content of variable amounts of foreign regions, which may lead to anti-drug antibodies (ADA) development. ADA onset may limit the clinical usage of biologicals because they may decrease their safety. In fact they are mainly associated with immediate hypersensitivity reactions (HSRs). Development of ADAs is reduced by concomitant immunosuppressive treatment, while it is increased by longer intervals between drug administrations; thus, regular infusion regimens should be preferred to reduce HSRs. Once ADAs have formed, some procedures can be implemented to reduce the risk of HSRs. ADAs may belong to different isotype; the detection of IgE ADA is advisable to be assessed when high and early ADAs are detected, in order to reduce the risk of severe HRs. In patients who need to reintroduce the biological culprit, as alternative therapies are not available, drug desensitization (DD) may be applied. Desensitization should be conceptually dedicated to patients with an IgE-mediated HSR; however, it can be performed also in patients who had developed non-IgE-mediated HSRs. Although the underlying mechanisms behind successful DD has not been fully clarified, the DD procedure is associated with the inhibition of mast cell degranulation and cytokine production. Additionally, some data are emerging about the inhibition of drug-specific immune responses during DD.