FMXIN002 Double Dose Delivers Faster Epinephrine Exposure Than Autoinjector

Double-dose FMXIN002 (NS002), an investigational intranasal epinephrine powder, produced faster and more sustained epinephrine exposure than a double-dose autoinjector in adults with allergic rhinitis, according to a late-breaking abstract at the 2026 American College of Allergy, Asthma & Immunology (ACAAI) Annual Scientific Meeting in Phoenix.¹

Repeat epinephrine dosing has been reported in 8% to 28% of patients treated for anaphylaxis, so how well a second dose performs is a central question for any needle-free option.¹ Nasus Pharma’s earlier phase 2 dose-finding study compared single 3.6-mg and 4-mg doses of the powder with a 0.3-mg epinephrine autoinjector (EpiPen) in healthy adults.² The double-dose study extends this work to repeat administration.

“What’s important here versus a liquid epinephrine formulation is with this particular powder, you can get uniform nasal surface adhesion and minimal runoff or drip,” said Michael S. Blaiss, MD, clinical professor at the Medical College of Georgia at Augusta University, in an interview with HCPLive. “It’s important you get high and fast absorption of epinephrine throughout your body to counteract the manifestations of anaphylaxis.”

FMXIN002 Double-Dose Study Design and Pharmacokinetic Results

The comparative bioavailability study enrolled 50 adults with allergic rhinitis.¹ Participants received 2 doses of FMXIN002 4 mg given 10 minutes apart, in the same or contralateral nostril. Doses were given under normal conditions or following a nasal allergen challenge (NAC) to elicit congestion.¹ A double dose of a 0.3-mg autoinjector served as the comparator, and plasma epinephrine was measured from predose to 4 hours postdose.¹

Blaiss explained the 10-minute interval reflects clinical practice, in which a second dose is typically given within 10 minutes when a patient does not respond to the first. He added the US Food and Drug Administration (FDA) requires repeat-dose studies to confirm a second dose can be given safely and reaches target pharmacokinetic and pharmacodynamic levels. The NAC was included because patients in anaphylaxis develop significant nasal congestion, and impaired absorption under those conditions would call the product’s suitability into question.

Across dosing conditions, FMXIN002 produced shorter or comparable median time to maximum concentration (Tmax) and consistently shorter time to 100 pg/mL (T100pg/mL) vs the autoinjector (P <.01).¹ Maximum concentration (Cmax) and area under the curve (AUC) were comparable or greater with FMXIN002.¹ Within the first 2.5 minutes, 60% to 82% of participants receiving FMXIN002 reached plasma epinephrine of ≥ 100 pg/mL, compared with 16.7% of those receiving the autoinjector (P <.001).¹

Blaiss said early epinephrine levels with FMXIN002 were above autoinjector levels within the first 5 minutes and peaked above them at approximately 20 minutes.

“It didn't matter whether it was given in the same nostril or contralateral nostril,” Blaiss said. “The reason you do both nostrils is to make sure again that if you do opposite nostrils versus the same nostril in an anaphylactic reaction, you still get excellent absorption. That's what we're able to show in this particular study.”

References

1. Blaiss M, Lapidot T, Megiddo D, Abrutzky C, Temtsin Krayz G. Enhanced absorption of intranasal powder epinephrine (FMXIN002) after double dose in adults with allergic rhinitis. Presented at the American College of Allergy, Asthma & Immunology 2026 Annual Scientific Meeting on November 14, 2026; Phoenix, AZ.

2. Lapidot T, Tal Y, Megiddo D, et al. First-in-class intranasal epinephrine spray for anaphylaxis: dose finding clinical study. J Allergy Clin Immunol Glob. 2025;4:100487. doi:10.1016/j.jacig.2025.100487