A recently developed nasal spray could revolutionize vaccination techniques.
There are many ways to take medicines. Most are given orally, though vaccines and rapid-acting drugs are usually given by injection.
Nasal sprays have primarily been used for preparations for colds and allergies, but delivery via the nose is also a possibility for many vaccines and other types of medicine. Until now, an important limitation to more widespread use of nasal delivery has been the problem of getting the active agent to the right place, in the right dose. This problem has now been solved by a new method developed by the Norwegian company OptiNose.
Norwegian/EU research project
OptiNose won the 2000 Venture Cup Prize, for which the criteria are a good business idea and an interesting product. Since then, the company has received a great deal of financial support from the Research Council of Norway, the State Industrial and Regional Development Fund, the national FUNN/Skattefunn funding scheme and EU’s CRAFT Programme. OptiNose has contracted out parts of its research and product development programme to SINTEF, where Tone Øderud has led a consumer study of doctors and patients, while Erik Andreassen and Rune Gaarder have been working on technical solutions for the release mechanism.
Part of their work has dealt with airflow analysis: “With this new apparatus the spray is released automatically when the patient blows into a mouthpiece, creating an airflow. One of the challenges has been to obtain controlled release of the spray, with the right range of velocities and distribution of particle sizes”, says Andreassen. “New products for the pharmaceutical industry, such as this, are an exciting area for people like us who work in materials science and microtechnology. For mass vaccination programmes, for example, cheap disposable units are of interest, and these demand simple, smart solutions in polymer materials”.
Inlet port for medicines
The foremost part of the nasal cavity is covered with skin and is thus not very suitable for absorbing medicines. Further back, however, the nasal cavity is equipped with a mucous membrane with a rich blood flow and large numbers of immune cells. It is in this area that medication can be absorbed into the bloodstream and vaccines can stimulate local immune defence mechanisms. The nerve cells in the olfactory organ at the upper end of the nasal cavity are really an extension of the brain itself.
This makes these cells a potential inlet port for drugs and vaccines targeted at the brain. The new spray operates in the following way: the patient has a container with two openings, one of which is a mouthpiece, while the other is an anatomically adapted nosepiece that is inserted into one nostril. When the patient blows into the mouthpiece a spray of particles is automatically released and blown into the nostril. When we blow out, the flap of tissue at the top of the throat always closes, so that the spray cannot enter the throat and lungs. The air is blown out through the other nostril. The medicine can be distributed to different parts of the nasal cavity by modifying the range of particle sizes and the airflow itself.
“When we use a traditional nasal spray, a large part of the dose runs down the base of the nasal cavity, into the mouth and on to the stomach, often producing a bad taste and some discomfort. Daily use of anti-allergy sprays may also result in irritation and bleeding in the frontal part of the nasal cavity. With this new method of delivery we can optimize the distribution of medicines and vaccines, so that their effects, user-friendliness and safety are all maximized”, says chief scientist Per G. Djupesland, who is one of the founders of OptiNose. Nasal delivery of drugs and vaccines eliminates the prick of the hypodermic needle, as well as preventing infection, whether caused by accident or syringe re-use. The method is also extremely suitable for mass vaccinations in developing countries, where hygiene may be poor and resources are limited. OptiNose is currently discussing nasal vaccine projects with international organizations.
“Our close cooperation with highly qualified experts at SINTEF and the other Norwegian technology companies in the CRAFT Programme has been extremely important for OptiNose. We have made a great deal of progress in product development within a short time”, says Djupesland. OptiNose products are aimed at an international market, and the first device will soon be ready for production.
By Jan Helstad