One-Dilution Rapid Desensitization Protocol to Chemotherapeutic and Biological Agents: A Five-Year Experience

How to Define and Manage Low-Risk Drug Allergy Labels

Risk stratification in drug allergy implies that specific risk categories (eg, low, moderate, and high) classify historical drug hypersensitivity reactions. These risk categories can be based on reaction phenotypic characteristics, the timing of the reaction and evaluation, the required reaction management, and individual characteristics. Although a multitude of frameworks have been described in the literature, particularly for penicillin allergy labels, there has yet to be a global consensus, and approaches continue to vary between allergy centers. Immune-mediated drug allergies can sometimes be confirmed using skin testing, but a negative drug challenge is required to demonstrate tolerance and remove the allergy from the electronic health record ("delabel" the allergy). Even for quintessential IgE-mediated drug allergy, penicillin allergy, recent data reveal that a direct oral challenge, without prior skin testing, is an appropriate diagnostic strategy in those who are considered low-risk. Drug allergy pathogenesis and clinical manifestations may vary depending on the culprit drug, and as such, the optimal approach should be based on risk stratification that considers individual patient and reaction characteristics, the likely hypersensitivity reaction phenotype, the drug class, and the patient's clinical needs. This article will describe low-risk drug allergy labels, focusing on β-lactam and sulfonamide antibiotics, nonsteroidal anti-inflammatory drugs, iodinated contrast media, and common chemotherapeutics. This review will also address practical management approaches using currently available risk stratification and clinical decision tools.

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.

Pearls for practice from the 2022 joint task force drug allergy practice parameter

PURPOSE OF REVIEW

To review updated recommendations in the 2022 Drug Allergy Practice Parameters for the evaluation and management of drug hypersensitivity reactions.

RECENT FINDINGS

Adverse drug reactions have become increasingly prominent with the advent of new and emerging pharmacologic therapies. Hypersensitivity reactions encompass a significant proportion of adverse drug reactions and negatively impact both the individual patient and overall health system. Reactions are heterogeneous in presentation and may be immediate (onset of symptoms ≤6 h) or delayed (onset of symptoms >6 h to months) after drug exposure. The 2022 Drug Allergy Practice Parameter provides consensus-based statements for evaluation of hypersensitivity reactions to antibiotics, NSAIDs, cancer chemotherapies, immune checkpoint inhibitors, biologics, and excipients. In general, the guideline highlights the importance of patient history in elucidating the phenotype and severity of the index reaction. Drug challenge remains the gold standard for diagnosis and is increasingly favored over skin testing in patients with nonsevere, nonanaphylactic drug reaction histories.

SUMMARY

The 2022 Drug Allergy Practice Parameter provides an updated framework for physicians to reference in clinical practice when managing patients with drug hypersensitivity reactions.

Outcomes of a Undiluted, One-Bag Desensitization Protocol for Chemotherapeutic Agents

BACKGROUND

Hypersensitive reactions (HSRs) often require that the provoking medication be discontinued but chemotherapeutic drugs are often essential for the treatment of the disease. Rapid drug desensitization is a procedure that induces temporary tolerance to the drug allowing continuation of treatment in patients who have presented HSRs. Most of the desensitization protocols use 3 bags with sequential dilutions of the drug, which are infused in gradual steps. However, it has not been sufficiently investigated whether dilution is essential for successful desensitization.

OBJECTIVE

The objective of this study was to evaluate the efficacy and safety of a new one-bag desensitization protocol which uses a single solution of 1 mg/mL throughout the procedure allowing to reduce time and simplifying the desensitization procedure.

METHODS

Retrospective observational study was carried out in adult patients with HSRs to chemotherapy agents who received a new nondilution one-bag desensitization protocol between 2016 and 2021.

RESULTS

A total of 130 desensitization procedures with an undiluted one-bag protocol were performed on 17 patients with HSRs to chemotherapy. One hundred and seven (82.3%) were for desensitization to CBDCA, 15 (11.5%) for oxaliplatin, 4 (3.1%) for paclitaxel and 4 (3.1%) for brentuximab. All of the 130 procedures were successfully accomplished, and all patients could receive their target dose. No breakthrough reactions (BTRs) occurred in 77% (100/130) of desensitizations, and only mild reactions (grade 1) with skin symptoms were observed in 23% (30/130) of desensitizations.

CONCLUSION AND RELEVANCE

The undiluted one-bag desensitization protocol was safe and effective and has been adopted as the standard of care at our institution in treating patients with HSRs to chemotherapeutic drugs as it requires less time and simplifies the desensitization procedure, optimizing risk management.

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.

Same-Day Desensitization in Patients Who Experience Their First Reaction to a Platin Agent at the Oncology Day Unit: A Pilot Study to Safely Include This Technique Within the Multidisciplinary Pathways for the Diagnosis & Management of Hypersensitivity to Platin Agents

One of the main objectives when assessing patients who react to antineoplastics must be to ensure that they receive the required treatments without delay. From January to July 2021, at the Allergy Department at the Provincial University Consortium Hospital a pilot study was performed in which those patients suspected of having suffered a type I hypersensitivity reaction (grade 1 or 2) following Brown's anaphylaxis severity grading to a platin agent at the Provincial University Consortium oncology day unit, and once the reaction was properly treated and completely resolved, were subjected to a new procedure named as Same-Day Desensitization, which consists in the reintroduction and administration of full chemotherapy dose by allergists on the same day of the reaction by following the 1 bag/10 step protocol, looking forwards to systematize same-day reexposure using Same-Day Desensitization, doing it in the safest way possible. In total, 9 oncological patients suspected of having suffered a type I hypersensitivity reaction (grade 1 or 2) to a platin agent received total dose administration the same day of the initial reaction by following Same-Day Desensitization 1 bag/10 step protocol, without presenting further reactions. The manuscript describes a new approach in the use of Rapid Drug Desensitizations in reactive oncologic patients in treatment with platin agents, presenting the first 9 cases of oncologic patients who have been submitted to this procedure.

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.

Analysis of Breakthrough Reactions in 1,143 Desensitization Procedures in a Single Tertiary Hospital Using a One-Bag Desensitization Protocol

Background

Drug desensitization is helpful for patients who have experienced significant hypersensitivity reactions (HSRs) to antineoplastic agents. One-bag desensitization protocols, attracting attention in recent years, need to be validated on their safety and efficacy in a large number.

Methods

One-bag desensitization procedures conducted from 2018 to 2020 were analyzed; their outcomes and the risk factors for breakthrough reactions (BTRs) were assessed in desensitization procedures to major drug types (platins, taxanes, and monoclonal antibodies).

Results

A total of 1,143 procedures of one-bag desensitization were performed in 228 patients with 99% completion rate. BTRs occurred in 26% of the total desensitization procedures—34% in platins, 12% in taxanes, and 18% in mAbs. BTR occurrence rate decreased along the desensitization process with 80% of BTRs occurring within the 6th desensitization attempts. Severe BTR occurred more frequently with severe initial HSRs (1% in mild to moderate initial HSRs vs. 16% in severe). Severe initial HSR was also a significant risk factor for moderate to severe BTR in platins (odds ratio 1.56, 95% confidence interval [CI] 1.06–2.29, p = 0.025). The use of steroid was also associated with lower occurrence of moderate to severe BTR (odds ratio 0.50, 95% CI 0.35–0.72, p < 0.001).

Conclusion

Most patients with HSRs to antineoplastic agents can safely receive chemotherapy through a one-bag desensitization protocol. Further studies on each drug with larger sample size can help verify the risk factors of BTRs and evaluate the efficacy of steroid premedication in improving the safety of desensitization in high-risk patients.

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.