Author response

Abstract

Dr Rackley makes 2 primary assertions in his letter, both of which do not appear to be supported by available information. First, he questions selection of the industry standard parameters area under the curve (AUC) and maximum plasma concentration (Cmax) to demonstrate that EpiPen and Auvi-Q have comparable bioavailability while partial AUC (derived from time after administration of a drug when the maximum plasma concentration is reached [Tmax]) is excluded. Second, he suggests that the newly designed Epipen “reduces the risk of needle-related injuries” (presumably compared with the original EpiPen for which unintentional injections were previously reported). 1 Simons F.E. Edwards E.S. Read Jr., E.J. Clark S. Liebelt E.L. Voluntarily reported unintentional injections from epinephrine auto-injectors. J Allergy Clin Immunol. 2010; 125: 419-423.e4 Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar , 2 Dey launches and unveils next-generation, needle-protected EpiPen® (epinephrine) auto-injector with enhanced patient-friendly features [press release]. Basking Ridge, NJ: Mylan Specialty; October 26, 2010. www.mylanspecialty.com/press_room/102609.aspx. Accessed August 1, 2013. Google Scholar Pharmacokinetic parameters for assessing bioequivalence of epinephrine autoinjectorsAnnals of Allergy, Asthma & ImmunologyVol. 112Issue 3PreviewWe were interested in the recent publication regarding a bioavailability study comparing epinephrine delivery from the EpiPen (Mylan Specialty LP, Basking Ridge, New Jersey) and Auvi-Q (sanofi-aventis US LLC, Bridgewater, New Jersey) epinephrine autoinjectors (EAIs) by Edwards et al.1 The stated objective of the study by Edwards et al was “to compare the bioavailability of 0.3 mg of epinephrine (adrenaline) injected with Auvi-Q and EpiPen in healthy adults.” Although the reported data suggested that Auvi-Q EAI was bioequivalent with respect to total exposure (overall area under the curve [AUC]) and peak exposure, these findings represent only a subset of pharmacokinetic parameters that might be evaluated in a formal bioequivalence study relative to EpiPen EAI, which may include partial AUC (ie, AUC evaluated from time zero to the median time of peak exposure [Tmax] of the reference), which allows for assessment of early exposure and speed of absorption. Full-Text PDF