The activity of monomer [K6T]P8 was also tested in synovial fluids from rheumatoid arthritis patients that normally showed high levels of IL-15, and consequently of TNFα [82].Both P8 and [K6T]P8 peptides were able to inhibit TNFα secretion, with the latter endowed with greater efficacy [79]. This evidence concerns the gene TNF and rheumatoid arthritis.