Firmagon, the newly FDA approved gonadotropin-releasing hormone (GnRH) receptor blocker should perhaps be considered as a better alternative to the traditionally used ADT drugs like lupron and zoladex (GnRH agonists) which are the current standard of care.

Recent data released from the ongoing five-year Firmagon (degarelix) extension study (CS21a) has demonstrated the long term efficacy and tolerability in study patients with advanced hormone-dependent prostate cancer. This study supports using Firmagon as first-line androgen deprivation therapy. Details of this study were announced today at the European Association of Urology (EAU) 2011 Annual Meeting.

Firmagon is indicated for the treatment of men with advanced hormone-dependent prostate cancer. The extension study of the pivotal Firmagon vs. leuprorelin trial (CS21) was designed to collect extended safety and tolerability data. At the closure of the Phase III trial, all men participating were offered the option to receive Firmagon as part of the extension study. All men who elected to and received Firmagon continued with their treatment and those who had previously been treated with leuprorelin (a GnRH agonist) were re-randomized to receive either Firmagon 240/80mg or 240/160mg.

To date, data from the extension study show that all patients receiving Firmagon experienced improved PSA control, specifically:
– Beyond one year, prostate-specific antigen (PSA) suppression was maintained in patients continuing treatment on Firmagon [1,2]
– After switching to Firmagon) patients who initially received leuprorelin experienced:
– Improved PSA control (0.20 vs 0.08 events/year; p=0.003)[1,2]
– A significantly lower rate of PSA failure or death[1,2]
– Tolerability of Firmagon was maintained throughout the extended study period[1,2]

“The data from the ongoing extension study demonstrated that the efficacy of Firmagon remains strong over the long term, providing prostate cancer patients with sustained PSA control,” said Professor Laurent Boccon-Gibod, Professor of Urology, Centre Hospitalo-Universitaire Bichat, Paris. “This is further evidence of the benefits of starting and staying on Firmagon and that it can be used as a first-line androgen deprivation therapy for advanced hormone-dependent prostate cancer patients.”

Firmagon has unique chemical characteristics and a novel mechanism of action, different from traditionally used hormonal therapies. Administered as a subcutaneous injection, it rapidly reduces levels of prostate specific antigen (PSA) within two weeks by immediately blocking the GnRH receptors in the pituitary gland. Blocking the receptors suppresses the release of the luteinising hormone (LS) and follicle-stimulating hormone (FSH), resulting in a decrease in production of testosterone by the testicles to castration levels within three days.

In other clinical studies, Firmagon suppressed testosterone and PSA faster than leuprorelin, an existing treatment for advanced prostate cancer.[3]

In clinical trials Firmagon was generally well tolerated. Common side effects are hot flushes, injection site pain and erythema (rash), increased weight, nasopharyngitis (cold like symptoms), fatigue and back pain.[3,4]

When I went back on ADT, I elected not to use Zoladex as I had during prior ADT, but instead to use Firmagon. The initial “loading dose” of Firmagon involves two painless injections. I developed cellulites (deposits beneath the skin which are common and an infection which was probably the result of bacteria being introduced during the injections). The other side effects have been easier to tolerate then when I received Zoladex.

[1] Tombal, B, Schroder, F, Miller, K et al. Long-term prostate-specific antigen (PSA) control in prostate cancer: continuous degarelix or degarelix following leuprolide. EAU 2011, Symposium Abstract 1088. 26th Annual EAU Congress, Vienna, 18-22 March 2011.
[2] Crawford, ED, Moul, JW, Shore, ND et al. Switching from leuprolide to degarelix vs continuous degarelix treatment – effects on long-term prostate-specific antigen control. J Urol 2010; 183 (Suppl): e262, abstract 670
[3] Klotz L, Boccon-Gibod L, Schroder FH et al. The efficacy and safety of degarelix: a 12-month, comparative, randomized, open-label, parallel-group phase III study in patients with prostate cancer. BJU Int. 2008;102(11 ):1531-1538.
[4] Van Poppel H, De La Rosette JJ, Persson B.E et al. Degarelix Study Group; Long-term evaluation of degarelix, a gonadotrophin-releasing hormone (GnRH) receptor blocker, investigated in a multicentre randomised study in prostate cancer (CAP) patients. Abstract (23.) Euro Urol Suppl 2007;6(2):28
[5] University of Iowa Hospitals and Clinics. Available at: [Accessed 16 February 2011]
[6] American Cancer Society. Available at: [Accessed 16 February 2011]
[7] Cancer Research UK. Available at: [Accessed 16 February 2011]

Taken from a news release published by Ferring

Joel T Nowak, M.A., M.S.W.