The following is a summary of “A 13.2 mg epinephrine intranasal spray demonstrates comparable pharmacokinetics, pharmacodynamics, and safety to a 0.3 mg epinephrine autoinjector,” published in the May 2024 issue of Allergy & Immunology by Dworaczyk, et al.

Recent updates to acute anaphylaxis guidelines have highlighted the critical need for improved therapeutic options. For a study, researchers sought to compare the pharmacokinetic, pharmacodynamic, safety, and tolerability profiles of intranasal epinephrine with intramuscular epinephrine administered via autoinjector and manual syringe.

An open-label, three-period crossover study was conducted with 116 healthy adult volunteers to assess the bioavailability of a single 13.2 mg intranasal dose of epinephrine compared to a 0.3 mg intramuscular autoinjector and a 0.5 mg manual syringe. Epinephrine concentrations were measured at 10, 20, 30, and 60 minutes post-dosing at 50, 100, and 200 pg/mL thresholds.

The pharmacokinetic parameters for the 13.2 mg intranasal dose surpassed those of the 0.3 mg autoinjector, showing a rapid and higher maximum observed concentration (intranasal: 429.4 pg/mL; autoinjector: 328.6 pg/mL) and greater systemic exposure (AUC_0-360: intranasal, 39,060 pg∙min/mL; autoinjector, 17,440 pg∙min/mL). Similar results were found in comparison to the 0.5 mg manual syringe. Intranasal dosing in both opposite-nostril and same-nostril conditions yielded higher pharmacokinetic parameters than both intramuscular doses, except for the time to reach the maximum observed concentration, which was 20 minutes for intranasal doses, compared to 14.9 minutes for the autoinjector and 45 minutes for the manual syringe. Blood pressure and heart rate effects were comparable between intranasal and autoinjector administration. Intranasal epinephrine was safe and well-tolerated, with no severe or unexpected adverse events reported, corroborating earlier clinical studies.

The bidose epinephrine spray offered a needle-free, convenient, and effective dose-delivery system for self-administration. It met unmet medical and patient needs and demonstrated efficacy comparable to or better than the 0.3 mg autoinjector.

Reference: jaci-global.org/article/S2772-8293(23)00125-X/fulltext