From Mdwiki - Reading time: 9 min
| Names | |
|---|---|
| Trade names | Firmagon, others |
| Other names | FE-200486 |
| Clinical data | |
| Drug class | GnRH analogue; GnRH antagonist; Antigonadotropin |
| Main uses | Prostate cancer[1] |
| Side effects | Pain at site of injection, hot flushes, liver problems[1] |
| Pregnancy category | |
| Routes of use | Subcutaneous injection |
| External links | |
| AHFS/Drugs.com | Monograph |
| MedlinePlus | a609022 |
| Legal | |
| License data | |
| Legal status | |
| Pharmacokinetics | |
| Bioavailability | 30–40% |
| Protein binding | ~90% |
| Metabolism | Subject to common peptidic degradation during passage through the hepato-biliary system; not a substrate for the human CYP450 system |
| Elimination half-life | 23–61 days |
| Excretion | Feces: 70–80% Urine: 20–30% |
| Chemical and physical data | |
| Formula | C82H103ClN18O16 |
| Molar mass | 1632.29 g·mol−1 |
| 3D model (JSmol) | |
| |
| |
Degarelix, sold under the brand name Firmagon among others, is a medication used to treat prostate cancer.[1][4] Specifically it is used for advanced disease that is hormone dependent.[5] It is given by injection under the skin.[5]
Common side effects include pain at the site of injection, hot flushes, and liver problems.[1] Other side effects may include anaphylaxis, QT prolongation, and infertility.[1] Use in pregnancy may harm the baby.[1] It is a GnRH receptor antagonist and works by reducing the amount of testosterone in the body.[1][6]
Degarelix was approved for medical use in the United States in 2008 and Europe in 2009.[4][6] In the United Kingdom 80 mg cost the NHS about £130 as of 2021.[5] In the United States this amount costs about 520 USD.[7]
Degarelix, through its ability to reduce serum testosterone, is used to treat hormone-sensitive prostate cancer.[8]
It is given at an initial dose of 240 mg followed by 80 mg every 4 weeks.[5]
As with all hormonal therapies, degarelix is commonly associated with hormonal side effects such as hot flashes and weight gain.[8][9][10] Due to its mode of administration (subcutaneous injection), degarelix is also associated with injection-site reactions such as injection-site pain, erythema or swelling. Injection-site reactions are usually mild or moderate in intensity and occur predominantly after the first dose, decreasing in frequency thereafter.[8] Less common: Anemia. Diarrhea, nausea. Hyperhidrosis including night sweats, rash. Gynecomastia, testicular atrophy, erectile dysfunction. Increased transaminases. Musculoskeletal pain and discomfort. Dizziness, headache. Insomnia. Weight gain. Chills, fever, fatigue, flu-like illness.[11]
GnRH antagonists (receptor blockers) such as degarelix are synthetic peptide derivatives of the natural GnRH decapeptide – a hormone that is made by neurons in the hypothalamus. GnRH antagonists compete with natural GnRH for binding to GnRH receptors in the pituitary gland. This reversible binding blocks the release of LH and FSH from the pituitary. The reduction in LH subsequently leads to a rapid and sustained suppression of testosterone release from the testes and subsequently reduces the size and growth of the prostate cancer. This in turn results in a reduction in prostate-specific antigen (PSA) levels in the patient's blood. Measuring PSA levels helps to monitor how patients with prostate cancer are responding to treatment.[medical citation needed]
Unlike GnRH agonists, which cause an initial stimulation of the hypothalamic-pituitary-gonadal axis (HPGA), leading to a surge in testosterone levels, and under certain circumstances, a flare-up of the tumour, GnRH antagonists do not cause a surge in testosterone or clinical flare.[12] Clinical flare is a phenomenon that occurs in patients with advanced disease, which can precipitate a range of clinical symptoms such as bone pain, urethral obstruction, and spinal cord compression. Drug agencies have issued boxed warnings regarding this phenomenon in the prescribing information for GnRH agonists. As testosterone surge does not occur with GnRH antagonists, there is no need for patients to receive an antiandrogen as flare protection during prostate cancer treatment. GnRH agonists also induce an increase in testosterone levels after each reinjection of the drug – a phenomenon that does not occur with GnRH antagonists such as degarelix.[medical citation needed]
GnRH antagonists have an immediate onset of action leading to a fast and profound suppression of testosterone and are therefore especially valuable in the treatment of patients with prostate cancer where fast control of disease is needed.[medical citation needed]
In December 2008, the US Food and Drug Administration (FDA) approved degarelix for the treatment of patients with advanced prostate cancer in the United States.[13][14] It was subsequently approved by the European Commission at the recommendation of the European Medicines Agency (EMA) in February 2009, for use in adult males with advanced, hormone-dependent prostate cancer.[15] Ferring Pharmaceuticals markets the drug under the name Firmagon.[15]
Degarelix is studied for use as a chemical castration agent on sex offenders in Sweden.[16] A study published on April 29, 2020 in JAMA Psychiatry demonstrated a reduced the risk score for committing child sexual abuse in men with pedophilic disorder 2 weeks after initial injection.[17]
{{cite web}}: Missing or empty |title= (help)| External sites: | |
|---|---|
| Identifiers: |
|