A drug currently used to treat rheumatoid arthritis (RA) could offer fresh hope to sufferers of polycystic kidney disease by preventing the formation of cysts, findings from US studies in mice have shown.
Polycystic kidney disease is the most commonly inherited renal disease and is estimated to affect one in 800 people.
Currently, there are no treatments to prevent the development of kidney cysts, which can lead to end-stage renal failure. But new research has shown that the use of etanercept could halt cyst formation.
Dr Rong Li, from the Institute for Medical Research in Kansas City, Missouri and colleagues analysed cyst fluid taken from the kidneys of 10 patients with polycystic kidney disease, and compared it with fluid from normal kidneys.
The inflammatory signalling protein tumour necrosis factor-alpha (TNF-alpha) accumulated as high levels in the cystic fluid of patients of polycystic kidney disease.
To test the effect of TNF-alpha on cyst formation, a group of mice genetically engineered to have polycystic kidney disease were injected every week with 0.5 micrograms of TNF-alpha for four weeks.
No cysts were observed in the control mice, but four of the 10 injected developed cysts. A group of diseased mice were injected with 125 micrograms weekly of the TNF-alpha inhibitor etanercept. After 10 weeks of treatment, none of the 50 diseased mice developed any cysts.
Professor Robert Price, an expert in polycystic kidney disease at Kings College London, said that the research offered 'great promise' to sufferers.
'Patients will benefit greatly from reducing the development of cysts, which are a leading cause of renal transplants,' Price said.