Via EurekAlert!: "Using gene therapy, [researchers] found a way to help certain cells using an inactivated virus to produce more of a naturally-produced molecule soluble TNF receptor. This factor is under-produced in patients with periodontitis. The molecule delivered by gene therapy works like a sponge to sop up excessive levels of tumor necrosis factor, a molecule known to worsen inflammatory bone destruction in patients afflicted with rheumatoid arthritis, joint deterioration and periodontitis. ... Targeted Genetics released human trial results that showed the same gene therapy approach [had] positive affects in human patients with rheumatoid arthritis ... The company tested 127 human subjects and showed a 30 percent improvement in pain relief, and gain of function, among other enhancements using the gene treatment. ... The gene also delivers quite a bit of genetic bang for the buck. The periodontal tissues were spared from destruction by more than 60-80 percent with the use of gene therapy. ... If you deliver the gene into the target cells once, it keeps producing in the cells for a very long period of time or potentially for the life of the patient. This therapy is basically a single administration, but it could have potentially life-long treatment effects in patients who are at risk for severe disease activity."