Scientists are developing a gene therapy treatment for rheumatoid arthritis (RA) that will come in the form of a nasal spray.
Drugs can be delivered via the nose
Research is still at the laboratory stage, but the team at King's College, London, hope to start clinical trials within three years.
The spray would contain a gene that controls production of a natural anti-inflammatory substance.
RA is a joint condition that affects around 350,000 people in the UK.
Preliminary tests by the King's team suggest nasal drops or a spray would be an effective way to deliver a shot of the key compound - called Interleukin-10.
This compound not only switches off the harmful, inflammatory process that causes RA, it also seems to stimulate cells that can hold the potentially harmful immune system cells in check.
Other researchers have tested Interleukin-10 as a treatment for RA. However, when it is delivered by intravenous injection it has been shown to cause side effects such as generalised suppression of the immune system.
The King's team is hopeful that administering the IL-10 gene via the nose will produce a more targeted effect, rather than affecting the whole immune system, so avoiding side effects.
It could also be considerably cheaper than current immunotherapeutic drugs.
Lead researcher Dr Linda Klavinskis said: "Every step we take we are thinking about patients, and we hope this research will lead to a clinical trial when it is completed in three years' time."
Dr Madeleine Devey, of the Arthritis Research Campaign which is helping to fund the research, said: "This is exciting research with real potential to provide a new approach to therapy in rheumatoid arthritis.
"Despite the development of TNFalpha antibody therapy for RA, there is still a need to develop more precise ways of modulating the immune system.
"Plasmid therapy is a way of delivering a therapeutic gene to the site of inflammation safely and effectively.
"If successful, this could provide an important way to specifically interfere with the disease process in RA without affecting the immune system as a whole.
"This could provide long-term therapeutic benefits with fewer side effects and would be considerably less expensive than the existing biological therapies."