ARS Pharma Submits Response to FDA Complete Response Letter for neffy (epinephrine nasal spray)

ARS Pharma (ARS) announced today it has submitted a response to the US Food and Drug Administration (FDA) for the company’s New Drug Application (NDA) for neffy (epinephrine nasal spray) to treat type 1 allergic reactions, including anaphylaxis.¹

In a complete response letter (CRL) to the company in September 2023, the FDA requested that ARS complete a repeat dose pharmacokinetic (PK) / pharmacodynamic (PD) study of neffy under nasal allergen challenge (NAC) conditions and that the company provide updated nitrosamine testing per the agency’s draft guidance issued in August 2023.

ARS announced successful completion of the repeat dosing study in February² with results demonstrating that after NAC in study participants with seasonal allergic rhinitis, the neffy PK profile was greater than or similar to that observed with intramuscular epinephrine injection. The PD profile showed numerically higher mean drug concentrations than seen with the injectable comparator. Repeat doses of neffy administered in the same nostril vs once in each nostril provided greater exposure that was also greater than that observed after epinephrine injection for PK exposure and PD response at all time points.²

ARS noted at the time that the study results are consistent with findings from previous studies, showing significant surrogate marker responses as early as 1 minute after initial dosing—a sign that repeat doses of neffy fully activate reversal of anaphylaxis symptoms. Findings from this study also showed no “meaningful differences on PK/PD” compared with dosing of neffy under naturally induced nasal conditions.²

Today the company also said it had completed the nitrosamine testing requested with no measurable levels of nitrosamines detected.¹

“After approximately six months of receiving the CRL for neffy, we were able to pivot quickly to successfully complete the repeat dosing nasal allergen challenge study and updated nitrosamine testing with no measurable levels of nitrosamines detected, and submit our response to the CRL,” Richard Lowenthal, cofounder, president and CEO of ARS Pharma said in the company announcement.¹ “Based on multiple meetings with the FDA, we believe that we have responded fully and completely to the Agency’s concerns and appreciate its insights along the way. Our focus on addressing any requests from the FDA to optimize our labeling remains critical in our mission to bring neffy to patients, providers, and caregivers who continue to show substantial enthusiasm for a needle-free, safe, effective, and easy to carry epinephrine solution. We look forward to working with the FDA in our efforts to make neffy available to allergy patients as soon as possible.”¹

ARS submitted the original neffy NDA in August 2022. The FDA’s Pulmonary-Allergy Drugs Advisory Committee (PADAC) in May 2023 determined a favorable benefit-risk profile for the needle-free epinephrine delivery mechanism (16:6 for adults and 17:5 for children). There were no requests from PADAC for a repeat dose study during allergen-induced allergic rhinitis.¹

Based on the submission receipt date of April 2, 2024, and a review period of up to 6 months, ARS anticipates a PDUFA date of October 2, 2024.¹

References:

1. ARS Pharmaceuticals submits response to FDA complete response letter for neffy (epinephrine nasal spray). News release. ARS Pharmaceuticals. April 3, 2024. Accessed April 3, 2024. https://ir.ars-pharma.com/news-releases/news-release-details/ars-pharmaceuticals-submits-response-fda-complete-response
2. Halsey G. Neffy generates favorable PK/PD data under nasal allergen challenge in repeat dosing study requested by FDA. Patient Care. February 26, 2024. Accessed April 2, 2024. https://www.patientcareonline.com/view/neffy-generates-favorable-pk-pd-data-under-nasal-allergen-challenge-in-repeat-dosing-study-requested-by-fda