Chemistry: Generation 2+ LICA
IONIS-GHR-LRx is a ligand-conjugated (LICA) investigational antisense medicine designed to reduce the production of the growth hormone receptor (GHr) to decrease the circulating level of insulin-like growth factor-1 (IGF-1). IGF-1 is a hormone primarily produced in the liver that plays an important role in childhood growth and has anabolic effects in adults. Several different diseases result from abnormally low or high levels of IGF-1, or an inappropriate response to this hormone. When produced in excess, IGF-1 results in acromegaly, a chronic, slowly progressing and life-threatening disease.
About GHr and Acromegaly
Acromegaly is a chronic, slowly progressing and life-threatening disease most often caused by oversecretion of growth hormone (GH) by benign pituitary tumors. Elevated levels of GH can overstimulate growth hormone receptors (GHr) and induce excess production of insulin-like growth factor-1 (IGF-1). High levels of circulating GH and IGF-1 lead to this multisystem disease characterized by organ overgrowth and physical disfigurement, such as enlarged hands, feet, and facial features. Patients with acromegaly also experience multiple comorbidities, such as type 2 diabetes, hypertension, and respiratory complications, as well as premature mortality. Because IGF-1 mediates the majority of the growth-promoting action of GH, reducing GHr production could in turn decrease levels of IGF-1 and provide a potential treatment to patients with acromegaly. Current treatments to block IGF-1 include surgical removal of the pituitary gland, which is often unsuccessful. Drug treatments to normalize IGF-1 levels are also available but are associated with potentially serious side effects.