Gonadorelin receptor agonists

The group of gonadorelin receptor agonists, also known as gonadorelin super agonists, comprises substances that have an increased affinity and binding time to gonadorelin receptors, as well as increased metabolic stability, compared to endogenous ligands (native gonadorelin).

Gonadorelin receptor agonists lead to a permanent stimulation of the FSH- or LH-producing cells of the anterior pituitary gland. These are normally subjected to pulsatile stimulation. The continuous receptor stimulation leads to a downregulation of the receptor number in the pituitary gland. This reduces the release of the gonadotropins FSH and LH from the anterior pituitary gland.

Thus, after an initial increase in testosterone concentration, there is a massive drop comparable to that after castration.

Prostate cancer patients treated in this way lived as long as patients who had had their testicles removed. However, 2 to 12.5% of patients do not reach the therapy goal of less than 50 ng/dl testosterone in serum.

Tumour therapeutics:especially prostate carcinoma, breast carcinoma.

• Buserelin
• Triptorelin

• Goserelin

• Leuprorelin

The disadvantage of this treatment method is the initially increased release of LH and FSH. This initial phenomenon usually lasts ten to 20 days. During this time, testosterone production is stimulated and the growth of the tumour cells is stimulated. As a result, patients with metastases may experience skeletal pain, urethal obstruction and spinal cord compression. To counteract this initial increase in testosterone, gonadorelin agonists must be combined with non-steroidal antiandrogens at the beginning.