2022 AF Symposium
Abstract: Trial II of InCarda Orally Inhaled Flecainide
Background: This abstract further elaborates on an 2021 AF Symposium Spotlight session by Dr. Jeremy Ruskin of Massachusetts General Hospital. He showed safety data from the InCarda Phase 2 study (INSTANT) which he thought very promising. This abstract details a small clinical trial.
Flecainide is a Class IC anti-arrhythmic that is prescribed daily in tablet form for many A-Fib patients. It can also be used as a “Pill in the Pocket” therapy.
The InCarda inhaler from InCarda Therapeutics, Inc., is a different delivery system, is portable, and used only as needed.
Inhaler For Rapid Absorption of Flecainide
When an A-Fib patient self-administers the InCarda inhaler, it produces a flecainide-containing aerosol when the patient inhales. This results in a rapid absorption of flecainide via the lungs into the heart.
It can terminate an A-Fib attack in as little as 8 minutes.
The tablet form of Flecainide takes around 1−3 hours to work.
The InCarda inhaler can be used like a Pill-In-The-Pocket therapy. This would free many A-Fib patients from daily use of Flecainide. This is a good thing, because Flecainide, like most antiarrhythmic drugs, can have bad side effects and be poorly tolerated over time.
Phase II Trials

InCarda inhaler from InCarda Therapeutics, Inc.
In a Phase II clinical trial of the inhaler, 97 patients received 120 mg of flecainide acetate oral inhalation solution (FleclH) during an 8-minute inhalation period.
Inhalation Safety Measures: Safety was evaluated based on peak plasma concentrations of flecainide, maximum QRS prolongation, cardiovascular events (CVEs) and adverse events. (Patients who did not convert to sinus were offered alternative treatment. They didn’t experience any adverse consequences.)
The Conversion Rate: At 90 minutes post-dose, the conversion rate to normal sinus rhythm was 47.5%, and the median time to conversion was 14.6 minutes from start of inhalation.
There were no significant safety differences in patients converting to normal sinus rhythm and those who didn’t.
The authors concluded, “Inhalation of 120 mg of flecainide (FleclH) was safe, and the efficacy was similar to that reported for oral and IV administration.”
Editor’s Comments
This InCarda inhaler is an incredible medical innovation for A-Fib patients! Imagine having an A-Fib episode and just using your flecainide inhaler to get you out of it in just 8 to 14 minutes! Think of how liberating that would be!
In clinical trial, the flecainide inhaler is testing just as effective as the tablet form−but currently the inhaler only works for patients about 50% of the time.
Many A-Fib patients would say that’s still a lot better than having to take flecainide as a tablet every day.
I’m hoping the dosage and formula will be adjusted to work better and more consistently.
Other Possibilities: Can the InCarda system be eventually used with other anti-arrhythmic drugs? Can it be used for anticoagulant delivery as well? The possibilities seem endless.
If you find any errors on this page, email us. Y Last updated: Tuesday, February 22, 2022
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