Obesity and the metabolic syndrome in men are associated with a high prevalence of hypogonadism of up to 50%. Increased fat mass leads to augmented release of adipocytokines and pro-inflammatory cytokines such as IL-1-beta, IL-6 and tumor necrosis factor-alpha which in turn suppress the hypothalamic-pituitary-gonadal (HPG) axis, leading to hypogonadism. This pathophysiological interplay is termed hypogonadal-obesity-adipocytokine hypothesis. TestIL is a prospective, multicenter, randomized, double-blinded, placebo-controlled trial to test the hypothesis that inhibition of IL-1-activity diminishes the inhibitory effects on HPG axis and increases testosterone levels in men with metabolic syndrome.

Obesity and the metabolic syndrome are considered as chronic low-grade inflammatory states. Elevated pro-inflammatory mediators in obesity and metabolic syndrome have an inhibitory effect on the hypothalamic-pituitary-gonadal axis (HPG axis) leading to hypogonadism. Decreased testosterone production in obese men in turn promotes additional fat deposition, contributing to a vicious cycle of fat accumulation. This complex pathophysiological interplay is termed hypogonadal-obesity-adipocytokine hypothesis, describing a bidirectional relationship between low levels of testosterone and the metabolic syndrome. TestIL is a prospective, multicenter, randomized, double-blinded, placebo-controlled trial to test the hypothesis that inhibition of IL-1-activity diminishes the inhibitory effects on HPG axis and increases testosterone levels in men with metabolic syndrome.