Biologics and anaphylaxis

Immunogenicity risk assessment and mitigation for engineered antibody and protein therapeutics

Remarkable progress has been made in recent decades in engineering antibodies and other protein therapeutics, including enhancements to existing functions as well as the advent of novel molecules that confer biological activities previously unknown in nature. These protein therapeutics have brought major benefits to patients across multiple areas of medicine. One major ongoing challenge is that protein therapeutics can elicit unwanted immune responses (immunogenicity) in treated patients, including the generation of anti-drug antibodies. In rare and unpredictable cases, anti-drug antibodies can seriously compromise therapeutic safety and/or efficacy. Systematic deconvolution of this immunogenicity problem is confounded by the complexity of its many contributing factors and the inherent limitations of available experimental and computational methods. Nevertheless, continued progress with the assessment and mitigation of immunogenicity risk at the preclinical stage has the potential to reduce the incidence and severity of clinical immunogenicity events. This Review focuses on identifying key unsolved anti-drug antibody-related challenges and offers some pragmatic approaches towards addressing them. Examples are drawn mainly from antibodies, given that the majority of available clinical data are from this class of protein therapeutics. Plausible and seemingly tractable solutions are in sight for some immunogenicity problems, whereas other challenges will likely require completely new approaches.

Safety and efficacy of rapid drug desensitization in children

BACKGROUND

Any drug taken at the recommended dosage may cause hypersensitivity reactions (DHR). Rapid drug desensitization (RDD) protocols have been developed in the case of a confirmed or highly suspected HSR to allow safe administration of the medicine when there is no alternative drug or in the presence of a less effective or more toxic alternative. The aim of this study was to evaluate the characteristics of children who underwent desensitization, the safety and efficacy of RDD in children, as well as, the characteristics and management of breakthrough reactions.

METHOD

This retrospective study concerned children who underwent RDD due to physician-diagnosed HSRs during or up to 48 hours after the infusion of various drugs between February 2010-February 2021. Patients with a chronic disease needing chronic drug usage and acute infections seen in patients with chronic diseases were included. The results of RDD were documented.

RESULTS

The study included 48 patients [8.1(IQR = 3.32-13.4) years, 60.4% male] with 58 HSRs of which 62.1% were classified as moderate and 5.2% as severe. Most of the patients were being treated for leukemia (41.7%), solid tumors (29.2%), and infections (6.3%). Skin tests were done for 41 out of 58 HSRs in 35 patients, and twenty of them were positive. A total of 269 RDDs were performed for 18 different drugs. Ninety percent of desensitizations were achieved with no reaction, and 3.7% and 5.6% with mild and moderate reactions, respectively. In multivariate analysis, skin test positivity was the only risk factor for breakthrough reactions (OR = 8.5, CI = 1.72-42.15, p = .009).

CONCLUSION

We demonstrated the safety and efficacy of RDD in childhood, thereby offered the first line treatment options to children with chronic diseases with hypersensitivity reactions (HSRs).

Cytokine release syndrome – a unique entity of Augmentin hypersensitivity reaction

Cytokine release syndrome (CRS) is a type of hypersensitivity reaction which has been previously described with chemotherapy and monoclonal antibodies, but not with antibiotics. We present 2 pediatric cases of Amoxicillin/Clavulanic acid (Augmentin) anaphylaxis resembling CRS. Both our patients presented during the index reaction with symptoms suggestive of an acute systemic inflammatory response mimicking sepsis. Their symptomology was reproducible at drug provocation test as anaphylaxis, but with suboptimal response to intramuscular adrenaline. Their infective workups were unremarkable and illnesses followed a self-limiting course. All these point towards a severe hypersensitivity reaction resembling CRS.

Biologics as treatment options for anaphylaxis

PURPOSE OF REVIEW

To provide the most recent insights in the use of biologicals in the treatment of patients with anaphylaxis.

RECENT FINDINGS

There is evidence that biologics such as omalizumab may be safe and effective in preventing anaphylactic reactions in patients at high risk mainly because of severe food allergy or desensitization procedures to food, airborne allergen, drugs, or hymenoptera venom.

SUMMARY

Further knowledge will guide the adoption and implementation of any new therapy including biologics for anaphylaxis according to the stratification of risk/benefits.

Anaphylaxis viewed by experts: unmet needs

PURPOSE OF REVIEW

The purpose of the review is to identify unmet needs in the management of anaphylaxis, covering aspects such as epidemiology, diagnosis, treatment and prevention.

RECENT FINDINGS

Redefinition of clinical diagnostic criteria may allow a better identification of anaphylaxis. International diagnostic coding system improvement will be major step for future policies and epidemiological studies. Digital health can aid in managing anaphylaxis.

SUMMARY

Anaphylaxis is a medical emergency; current data show that frequently identification of the reaction, acute and long-term management, are not optimal. Therefore, there is a need to implement strategies to improve the situation. This review has identified unmet needs in anaphylaxis regarding aspects such as epidemiology, severity scoring, definition and diagnostic criteria, anaphylaxis in infants and toddlers, cofactors, biomarkers, long-term management, undertreatment and availability of epinephrine autoinjectors. Strategies focused on education, legislation, digital health and research are proposed.

Mechanisms of Drug Desensitization: Not Only Mast Cells

Drug desensitization (DD) allows transient clinical tolerance to the drug in reactive patients and it is frequently and successfully used in the management of both IgE and non IgE-mediated hypersensitivity reactions (HRs). The underlying mechanisms behind this process is not well understood. The desensitization procedure is associated with the inhibition of mast cells degranulation and cytokine production, that, is attributable, at least partially, to the abrogation of Ca2+ mobilization; in vitro findings and in vivo mouse models of rapid desensitization show that the organization and spatial distribution of actin is critical for Ca2+ mobilization. Some clinical observations may suggest the induction of a longer memory of tolerance by DD and they raise the suspicion that other cells and mechanisms are involved in DD. Some data are emerging about the modifications of immune responses during DD in patients with previous immediate HRs. In particular, an increase of regulatory cytokines, mainly represented by IL-10, has been shown, and more importantly, the appearance of IL-35 producing T regulatory cells has been described during DD. The release of controlled cellular mediators by mast cells over time and the development of the antigen-specific regulation of adaptive response allow to safely and successfully reach the target dose of a first line drug during DD.

Emerging Causes of Drug-Induced Anaphylaxis: A Review of Anaphylaxis-Associated Reports in the FDA Adverse Event Reporting System (FAERS)

BACKGROUND

Drug-induced anaphylaxis is a well-known adverse drug reaction for some drug classes, but emerging drug causes of anaphylaxis and novel mechanisms may contribute in unrecognized ways.

OBJECTIVE

We sought to determine the top drugs reported in association with anaphylaxis and anaphylaxis followed by death in the Food and Drug Administration Adverse Event Reporting System (FAERS).

METHODS

We reviewed the publicly available FAERS database from 1999 to 2019. Using search terms "anaphylactic shock" or "anaphylactic reaction" and sorting cases by generic drug names, we counted and trended reports to FAERS in which a drug was associated with anaphylaxis or anaphylaxis followed by death.

RESULTS

From 1999 to 2019, there were 17,506,002 adverse drug events reported in FAERS, of which 47,496 (0.27%) were reported as anaphylaxis. Excluding patients without age, sex, or country data, respectively, the median age of patients in reports of anaphylaxis was 52 (interquartile range: 28), 62.71% were female, and 13,899 of 34,381 (40.43%) reports were from the United States. There were 2984 of 47,496 (6.28%) reports of anaphylaxis followed by death. Top drug classes associated with anaphylaxis in FAERS were antibiotics, monoclonal antibodies (mAbs), nonsteroidal anti-inflammatory drugs, and acetaminophen. Top drug classes associated with anaphylaxis deaths were antibiotics, radiocontrast agents, and intraoperative agents. Linear regression demonstrated reports of anaphylaxis to mAbs increasing at an average rate of 0.77% of total anaphylaxis reports per year (95% confidence interval: 0.65, 0.88) from 2.00% in 1999 to 17.37% in 2019, faster than any other drug class.

CONCLUSION

Antibiotics were highly reported for anaphylaxis overall and anaphylaxis followed by death. Increasing reports were noted for anaphylaxis to mAb therapies.

Rapid desensitization to brentuximab vedotin after severe anaphylaxis in the treatment of refractory Hodgkin's lymphoma

INTRODUCTION

Brentuximab vedotin is a monoclonal antibody drug conjugate used for the treatment of patients with Hodgkin lymphoma. Hypersensitivity reactions to brentuximab vedotin may include cutaneous, cardiovascular, respiratory, gastrointestinal and neurological signs and symptoms.

CASE REPORT

We present the case of a 23-year-old Mexican female with stage IV progressive classical nodular sclerosing Hodgkin lymphoma who received multiple previous chemotherapy regimens. Brentuximab vedotin at 1.8 mg/kg (180 mg total dose), for 21-day cycles was indicated. Within 5 min of infusion of the 5th cycle of brentuximab, she developed severe anaphylaxis (hives, angioedema, diaphoresis, tachycardia, dyspnea, hypoxemia and loss of consciousness), which was successfully controlled with epinephrine, steroids and antihistamines.Management and outcome: Intradermal skin test at a concentration of 0.1 mg/ml was positive. Due to the severity of the symptoms and the lack of access to alternative treatments, we performed a desensitization protocol. A total of 180 mg of brentuximab was given in three bag solutions in 12 steps, with an initial concentration dose of 1/100 of the total dose in a course of 5.56 h with no hypersensitivity reactions.

DISCUSSION

Severe anaphylaxis has been reported in 1.2% of patients receiving brentuximab vedotin. Patients who are treated by rapid drug desensitization with their first option therapy present a favorable survival rate with better cost-effectiveness in comparison to second-line treatment.

Hypersensitivity Reactions to Biologicals: from Bench to Bedside

Purpose of Review

Biologic agents are new treatment options for chronic inflammatory diseases and cancers. As a result of their unique mechanism of action, they are more effective and less toxic treatment option and their clinical usage is increasing. While they are more commonly used, various adverse effects have been observed including life-threatening ones, including anaphylaxis. The aim of this review is to distinguish the anaphylaxis from other hypersensitivity reactions (HSR) and provide a management algorithm for the anaphylactic reactions induced by biological agents.

Recent Findings

Many case reports and series have been published regarding anaphylaxis and other hypersensitivity reactions (concerning cytokine release syndrome, acute infusion–related reactions) due to biologic agents. Although acute treatment of HSR varies according to the clinical presentation, desensitization with the drug is the major management option for subsequent administrations in the case of anaphylactic reactions.

Summary

Anaphylaxis and other immediate onset hypersensitivity reactions are occasionally difficult to differentiate from each other, and mixed-type reactions may be observed. Immediate management of anaphylaxis includes discontinuation of infusion, immediate administration of adrenaline, antihistamines, corticosteroids, and other treatment options depending on the symptoms. After 30–120 min of the reaction, a blood sample for serum tryptase levels should be obtained and after 4–6 weeks skin testing with the culprit drug should be performed for decision of long-term management via either graded challenge or desensitization.

Global Trends in Anaphylaxis Epidemiology and Clinical Implications

The true global scale of anaphylaxis remains elusive, because many episodes occur in the community without presentation to health care facilities, and most regions have not yet developed reliable systems with which to monitor severe allergic events. The most robust data sets currently available are based largely on hospital admissions, which are limited by inherent issues of misdiagnosis, misclassification, and generalizability. Despite this, there is convincing evidence of a global increase in rates of all-cause anaphylaxis, driven largely by medication- and food-related anaphylaxis. There is no evidence of parallel increases in global all-cause anaphylaxis mortality, with surprisingly similar estimates for case-fatality rates at approximately 0.5% to 1% of fatal outcomes for hospitalizations due to anaphylaxis across several regions. Studying regional patterns of anaphylaxis to certain triggers have provided valuable insights into susceptibility and sensitizing events: for example, the link between the mAb cetuximab and allergy to mammalian meat. Likewise, data from published fatality registers can identify potentially modifiable risk factors that can be used to inform clinical practice, such as prevention of delayed epinephrine administration, correct posturing during anaphylaxis, special attention to populations at risk (such as the elderly on multiple medications), and use of venom immunotherapy in individuals at risk of insect-related anaphylaxis.