Pharmacology of Histrelin-Acetate

Histrelin is marketed by Endo Pharmaceuticals under the brand names Vantas and Supprelin LA.
In a process known as downregulation, daily stimulation of pituitary gonadotropes causes them to become desensitized to the effects of histrelin. As a consequence, levels of LH and FSH fall after a short period of time. From that point forward, as long as histrelin is administered, the levels of LH and FSH in the blood remain low.
This prolonged lowering of LH and FSH levels is the rationale for therapy using GnRH agonists. Since LH and FSH stimulate the gonads to produce estrogens and androgens in females and males respectively, histrelin can effectively be used to decrease the sex steroids in the blood of patients.