Comparative Usability Study of a Novel Auto-Injector and an Intranasal System for Naloxone Delivery

Introduction: The standard of care for reversal of opioid-induced respiratory depression associated with opioid overdose is injectable naloxone. This study compared the usability of two naloxone delivery devices, a naloxone auto-injector (NAI) and a naloxone intranasal delivery system (NXN), in the administration of naloxone during a simulated opioid overdose emergency. NAI (EVZIO((R)); kaleo, Inc., Richmond, VA, USA) is a Food and Drug Administration approved single-use pre-filled auto-injector containing 0.4 mg of naloxone. Methods: Study participants were randomly assigned to administer naloxone using NAI and NXN, sequentially. The primary endpoint was successful administration of a simulated dose of naloxone into a mannequin during a simulated opioid emergency, both before and after receiving training. Secondary endpoints included using the NAI or NXN in accordance with the instructions-for-use and the comparative measurement of successful completion time of administration for both NAI and NXN. Results: A total of 42 healthy participants aged 18-65 years were enrolled in the study. The proportion of participants able to successfully administer a simulated dose of naloxone was significantly greater for NAI compared to NXN both before (90.5% vs. 0.0%, respectively, P < 0.0001) and after (100% vs. 57.1%, respectively, P < 0.0001) participant training. The proportion of participants able to administer a simulated dose of naloxone in accordance with the instructions-for-use was also significantly greater for NAI compared to NXN before (85.7% vs. 0.0%, respectively, P < 0.0001) and after (100% vs. 0.0%, respectively, P < 0.0001) participant training. The average time to task completion for administration attempt before training was 0.9 +/- 0.25 min for NAI versus 6.0 +/- 4.76 min for NXN and after training was 0.5 +/- 0.15 min for NAI versus 2.0 +/- 2.15 min for NXN. Conclusion: Laypersons experienced substantially greater success administering a simulated dose of naloxone, both before and after training, using NAI versus NXN during a simulated opioid overdose emergency. No participants correctly used NXN without training.