A novel technology for delivering nicotine to the lungs has proven more effective at delivering nicotine at delivering nicotine to the blood stream compared with the vapor delivery system used in the Nicotrol/ Nicorette inhaler, providing more immediate relief of withdrawal symptoms. That is the conclusion of a study by Duke University Medical Center researchers.
Participants in the study also reported that the new nicotine delivery method was more tolerable than the current inhaler because it caused less throat irritation.
“We wanted to replicate the experience of smoking without incurring the dangers associated with cigarettes, and we wanted to do so more effectively than the nicotine-replacement therapies currently on the market,” said Jed Rose, PhD, Director of the Duke Center for Nicotine and Smoking Cessation Research, where the technology is being developed. He presented the data at the end of February at the Society for Nicotine and Tobacco Research Annual Meeting.
The Nicotrol inhaler is a smoking-cessation therapy that delivers nicotine vapor to the mouth and upper airways, but little of it reaches the lungs, he explained in a news release.
The new technology employs a way to deliver nicotine to the lungs, resulting in rapid absorption of nicotine, providing immediate relief of withdrawal symptoms and recreating some of the familiar sensations that are pleasurable to smokers.
Current methods that deliver medicine to the lungs such as metered dose sprays, dry powder inhalers, or nebulizers that create a fine mist, do not replicate the natural inhalation used by smokers when drawing on a cigarette, Dr. Rose noted, adding that because medication residue often deposits in the mouth and throat, doses aren't always high enough to ensure the appropriate amount reaches the lungs.
Duke's new technology combines the vapor phase of pyruvic acid, which occurs naturally in the body, and nicotine. “When the two vapors combine, they form a salt called nicotine pyruvate,” he said. “This reaction transforms invisible gas vapors into a cloud of microscopic particles which is inhaled, just like a smoker inhales from a cigarette.”
In the study, nine healthy smokers inhaled 10 puffs of nicotine pyruvate in increasing doses, 10 puffs from a Nicotrol/ Nicorette inhaler cartridge, and 10 puffs of room air. Blood was drawn before and after each set of inhalations. When the results were analyzed, there were rapid increases in plasma nicotine concentrations following the nicotine pyruvate inhalations and fewer complaints of harshness/irritation when compared with the situation for people using the Nicotrol/Nicorette control cartridge.
The smokers also said that their cravings for cigarettes were substantially alleviated following the nicotine pyruvate inhalations.
“Compared to the current nicotine vapor inhaler, we are able to give smokers more nicotine, although still less than a cigarette, with less irritation, resulting in reduced cravings,” Dr. Rose said. “Thus we are able to achieve a therapeutic effect with greater tolerability.”
More research is still needed, of course, but Dr. Rose said that if all goes well, that he expects that the product could become commercially available within three to five years.
The inhalation system could also theoretically be useful for delivery of other medications, he said. Duke has filed patent applications on the new technology, which was invented by Dr. Rose and his colleagues, including his brother, Seth D. Rose, PhD; Duke colleague Thangaraju Murugesan, PhD, and James E. Turner, an inventor of the Nicotrol/ Nicorette inhaler.