According to the results of a recently published study, FDANxSpray, the FDA-approved Narcan device for nasal administration, was found to yield higher plasma concentrations of naloxone compared to other devices used to treat opioid overdoses.

In the study, the authors aimed to compare the pharmacokinetics (PK) of the two FDA-approved naloxone devices (Evzio and FDANxSpray) to the non-FDA approved improvised nasal naloxone device (INND). Evzio, which gives audible instructions to autoinject 2mg of naloxone intramuscularly, was approved in 2014. FDANxSpray, which delivers 4mg of naloxone in 0.1mL intranasally, was approved 2015. In 2017, an FDANxSpray containing 2mg of naloxone in 0.1mL was approved, however, it is not currently marketed. The INND consists of a prefilled syringe of naloxone that is designed for parenteral use and is attached to a mucosal atomization device.

The inpatient, open-label, crossover study included 30 patients who were randomized into 5 treatment groups: 2mL of naloxone of a 1mg/mL solution via INND at 0 minutes; 2mL of naloxone of a 1mg/mL solution via INND at 0 and 2 minutes; 2mg of naloxone via 2mg FDANxSpray at 0 minutes; 4mg of naloxone via 4mg FDANxSpray at 0 minutes; 2mg of naloxone via Evzio autoinjector at 0 minutes. Patients received all 5 treatments over 10 days with 2 day washout periods between doses.

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The study authors reported that the highest maximum plasma concentration was achieved following intranasal administration of 4mg of naloxone via the 4mg FDANxSpray device. “The highest exposures at 5 minutes postdose, based on AUC values, were after administration with the autoinjector and the 4mg FDA-approved spray; at 10, 15, and 20 minutes postdose, the latter yielded the greatest exposure,” they stated. They added, “Even after 2 administrations, the INND failed to achieve naloxone plasma levels comparable to the FDA-approved devices at any time.”

Based on their findings, the study authors concluded that the FDA-approved 4-mg FDANxSpray should be considered when selecting a naloxone device to use based on its ease of use as well as its ability to produce higher plasma concentrations.

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