Re-visiting Hypersensitivity Reactions to Taxanes: A Comprehensive Review.

Taxanes (a class of chemotherapeutic agents) are an important cause of hypersensitivity reactions (HSRs) in cancer patients. During the last decade, the development of rapid drug desensitization has been key to allow patients with HSRs to taxanes to be safely re-treated although the mechanisms of these HSRs are not fully understood. Earlier studies suggested that solvents, such as Cremophor EL used to solubilize paclitaxel, were responsible for HSRs through complement activation, but recent findings have raised the possibility that some of these HSRs are IgE-mediated. Taxane skin testing, which identifies patients with an IgE-mediated sensitivity, appears as a promising diagnostic and risk stratification tool in the management of patients with HSRs to taxanes. The management of patients following a HSR involves risk stratification and re-exposure could be performed either through rapid drug desensitization or graded challenge based on the severity of the initial HSR and the skin test result. Rapid drug desensitization has been shown to be an effective and safe method to re-introduce taxanes in hundreds of patients, including those with life-threatening HSRs. Patients with non-severe delayed skin HSRs may benefit from rapid drug desensitization since they may be at increased risk for an immediate HSR upon re-exposure. This review focuses on the clinical presentation, diagnosis, and novel mechanisms of immediate HSRs to taxanes. A new management strategy for HSRs to taxanes based on skin testing and rapid drug desensitization is proposed.