An approval for a nasal spray to treat severe allergic reactions was denied on Tuesday by the US Food and Drug Administration (FDA), as it urged for more research on what would have been the alternative to injections using devices such as the EpiPen.

San Diego-based ARS Pharmaceuticals Inc. was told by the FDA that the firm must conduct more studies on repeated doses of epinephrine, a drug that stops potentially life-threatening allergic reactions called anaphylaxis, by using the company’s nasal spray device called neffy and compare it with injections.

This comes just four months following a recommendation by an FDA advisory committee to approve neffy. Even though the FDA usually abides by the recommendations, it is not obliged to.

President and chief executive of ARS, Richard Lowenthal, released a statement that his company intends to appeal the decision and resubmit an application early next year.

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Neffy is one of the needle-free devices to treat dangerous reactions to food, insect stings, and medications. This could be a treatment for between 33 million and 45 million Americans with severe allergies to the aforementioned. 

Advocates of the products that would help people in need of it claimed being “frustrated” by the FDA’s request for additional research.

In a statement, Sung Poblete, chief executive of the nonprofit Food Allergy Research & Education, said, “Our community believe this innovation would finally come to the more than 10% of Americans with life-threatening food allergies, but instead, the FDA will force us to wait even longer”.