New research published online in June in the journal “Nature Medicine” finds that the TNF inhibitor etanercept (Enbrel) may offer treatment and hope to people with autosomal dominant polycystic kidney disease (ADPKD). ADPKD is a genetically inherited renal disease that affects about 1 in 800 people. The disease causes the kidneys to develop cysts and since there are no treatments currently available to prevent the cysts, ADPKD can eventually lead to end stage renal failure and requiring kidney transplants.
The researchers at the Institute for medical Research in Kansas City, Missouri first analyzed several patients with the kidney disease and found that the fluid in the kidney cysts had high levels of tumor becrosis factor-alpha (TNF-alpha). They then genetically engineered mice to develop polycystic kidney disease, similar to their human patients, in order to study the effect of treating the mice with TNF-alpha inhibitors. The study mice were injected every week for four weeks with TNF-alpha, resulting in several developing kidney cysts. Then a group of 50 of the diseased mice were injected weekly with etanercept. After ten weeks of injections, no mice had developed any more cysts.
The researchers believe that the positive results of treatment with TNF-alpha inhibitors will be a promising step toward treatment for people with polycystic kidney disease. Further research will need to be conducted with human subjects. Also, etanercept is one of several TNF-alpha inhibitors, including adalimumab (Humira) and infliximab (Remicade). Perhaps future research might include these drugs as well.