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.

Desensitization for the prevention of drug hypersensitivity reactions

Drug desensitization is the temporary induction of tolerance to a sensitized drug by administering slow increments of the drug, starting from a very small amount to a full therapeutic dose. It can be used as a therapeutic strategy for patients with drug hypersensitivity when no comparable alternatives are available. Desensitization has been recommended for immunoglobulin E (IgE)-mediated immediate hypersensitivity; however, its indications have recently been expanded to include non-IgE-mediated, non-immunological, or delayed T cell-mediated reactions. Currently, the mechanism of desensitization is not fully understood. However, the attenuation of various intracellular signals in target cells is an area of active research, such as high-affinity IgE receptor (FcεRI) internalization, anti-drug IgG4 blocking antibody, altered signaling pathways in mast cells and basophils, and reduced Ca2+ influx. Agents commonly requiring desensitization include antineoplastic agents, antibiotics, antituberculous agents, and aspirin/nonsteroidal antiinflammatory drugs. Various desensitization protocols (rapid or slow, multi-bag or one-bag, with different target doses) have been proposed for each drug. An appropriate protocol should be selected with the appropriate concentration, dosage, dosing interval, and route of administration. In addition, the protocol should be adjusted with consideration of the severity of the initial reaction, the characteristics of the drug itself, as well as the frequency, pattern, and degree of breakthrough reactions.