Exploratory Efficacy Analysis Conducted for Long-Term Extension Study in Patients With Prostate Cancer Treated With FIRMAGON® or Crossed Over to FIRMAGON From Leuprolide
WASHINGTON, May 16, 2011 /PRNewswire/ -- A poster entitled, "Time to Progression in Patients with Prostate Cancer: A Comparison of Continuous Degarelix versus Degarelix Following Leuprolide Treatment," is being presented at the American Urological Association 2011 meeting by E. David Crawford, MD, head of the Section of Urologic Oncology at the University of Colorado Health Sciences Center in Denver, and lead study investigator. The full manuscript has just been accepted and will be published in the September 2011 issue of the Journal of Urology. Other investigators for the study, sponsored by Ferring Pharmaceuticals Inc., included J.W. Moul, N. Shore, E. van der Meulen, and B.E. Persson.
These latest PSA results were observed in the 5-year extension study portion (CS21A) of a pivotal one-year, open-label, randomized phase III trial (CS21) that evaluated the efficacy of FIRMAGON, a gonadotropin-releasing hormone (GnRH) antagonist, and leuprolide, a luteinizing hormone-releasing hormone (LHRH) agonist, and formed the primary basis of the approval of FIRMAGON for advanced prostate cancer.
After one year, 384 patients entered CS21A and 134 who had received leuprolide were re-randomized to receive FIRMAGON. The purpose of the extension study was to evaluate the safety and tolerability during long-term treatment with once-monthly injections of FIRMAGON 80 mg in patients with prostate cancer. Exploratory efficacy endpoints were evaluated and included: serum levels of PSA over time, cumulative probability of no PSA failure, serum levels of testosterone over time, cumulative probability of testosterone level maintained at less than or equal to 0.5 ng/dL from Day 28 in CS21 and onwards, and serum levels of testosterone, PSA, LH, and FSH from the time of switch from leuprolide to degarelix.
Both the cumulative probability of no PSA failure and the cumulative probability of testosterone levels below castrate level (less than or equal to 0.5 ng/dL) were estimated using the Kaplan Meier method using, respectively, PSA and testosterone measurements at the scheduled trial visits (CS21 and CS21A) for the ITT population.
At the median follow-up of 27.5 months, the PSA progression-free survival (PFS) hazard rate was 0.20 events/year for patients who crossed over from leuprolide compared with 0.08 events/year for patients treated continuously with FIRMAGON. PFS was defined as time to first PSA failure, or two consecutive increases in PSA of 50% and greater than or equal to 5 ng/dL. In addition, the time for the analyzed patients with baseline PSA levels greater than 20 ng/dL to experience PSA failure or death was 407 days for patients treated with FIRMAGON and 303 days for leuprolide-treated patients in CS21.
"This PSA data is very intriguing however, prospective clinical trials are needed to fully evaluate these outcomes in men with advanced prostate cancer," said Dr. Crawford.
About Study CS21
In the Phase III multicenter, randomized, open-label trial comparing FIRMAGON with leuprolide, prostate cancer patients (n=610) were randomized to a FIRMAGON starting dose of 240 mg for one month, followed by monthly maintenance doses of 80 mg (n=207) or 160 mg (n=202), or leuprolide 7.5 mg/month (n=201). The trial was powered to demonstrate non-inferiority of degarelix versus leuprolide for the primary end point (proportion of patients with testosterone suppression less than or equal to 50 ng/dL during 12 months' treatment). Data for the 240/160 mg group have not been analyzed beyond 1 year; after 1 year patients randomized to the 160 mg dose were switched to the approved 80 mg dose following regulatory approval of this dose. Patients crossed over from the leuprolide group were given FIRMAGON starting dose 240 mg followed by monthly maintenance dose of 80 mg.
FIRMAGON is an injectable gonadotropin-releasing hormone (GnRH) receptor antagonist approved in 2009 by the U.S. Food and Drug Administration (FDA) for the treatment of advanced prostate cancer. As a receptor antagonist, FIRMAGON reversibly binds to the GnRH receptors in the pituitary gland, immediately suppressing the secretion of the luteinizing hormone (LH), follicle-stimulating hormone (FSH), and subsequently, testosterone levels.(1-4)
FIRMAGON also reduces levels of prostate-specific antigen (PSA). Unlike luteinizing hormone-releasing hormone (LHRH) agonists, such as leuprolide, an established treatment for prostate cancer, FIRMAGON does not induce an initial testosterone surge. FIRMAGON is administered monthly by subcutaneous injection. The starting dose is 240 mg, followed by monthly maintenance doses of 80 mg. FIRMAGON is available for order through traditional and specialty pharmacy distributors. The average monthly cost of one year of FIRMAGON treatment is comparable to other hormone treatments for advanced prostate cancer.
Important Safety Information
FIRMAGON is contraindicated in patients with a known hypersensitivity to degarelix or to any of the product components and in women who are or may become pregnant. FIRMAGON can cause fetal harm when administered to a pregnant woman.
Long-term androgen deprivation therapy (ADT) prolongs the QT interval. Physicians should consider whether the benefits of ADT outweigh the potential risks in patients with congenital long QT syndrome, electrolyte abnormalities, or congestive heart failure and in patients taking Class IA or Class III antiarrhythmic medications.
Diagnostic test results of pituitary gonadotropic and gonadal functions conducted during and after FIRMAGON may be affected. The therapeutic effect of FIRMAGON should be periodically monitored by measuring serum concentrations of PSA; if PSA increases, serum concentrations of testosterone should be measured. The most common adverse reactions (greater than or equal to 10%) during FIRMAGON therapy included injection site reactions (eg, pain, erythema, swelling or induration), hot flashes, increased weight, fatigue, and increases in serum levels of transaminases and gamma-glutamyltransferase.
The majority of adverse reactions were Grade 1 or 2; 1% or less were Grade 3/4. Injection site reactions were mostly transient, of mild to moderate intensity, occurred primarily with the starting dose and led to few discontinuations (<1%).
About Ferring Pharmaceuticals Inc.
Ferring Pharmaceuticals Inc. is a subsidiary of Ferring Pharmaceuticals, a privately owned, international pharmaceutical company. Ferring Pharmaceuticals offers a line of products in the U.S. market. They include: BRAVELLE® (urofollitropin for injection, purified), MENOPUR® and REPRONEX® (menotropins for injection, USP), Novarel® (chorionic gonadotropin for injection, USP), ENDOMETRIN® (progesterone) Vaginal Insert, LYSTEDA™ (tranexamic acid tablets), FIRMAGON® (degarelix for injection), PROSED® DS (methenamine, phenyl salicylate, methylene blue, benzoic acid, hyoscyamine sulfate), DESMOPRESSIN, and EUFLEXXA® (1% sodium hyaluronate).
Ferring Pharmaceuticals specializes in the research, development and commercialization of compounds in general and pediatric endocrinology, urology, orthopaedics, gastroenterology, obstetrics/gynecology, and infertility. For more information, call 1-888-FERRING (1-888-337-7464) or visit www.FerringUSA.com.
(1) Degarelix [prescribing information]. Parsippany, NJ: Ferring Pharmaceuticals Inc.; December 2008.
(2) Klotz L, Boccon-Gibod L, Shore ND, 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.
(3) Van Poppel H, Tombal B, de la Rosette JJ, Persson B-E, Jensen J-K, Olesen TK. Degarelix: a novel gonadotropin-releasing hormone (GnRH) receptor blocker—results from a 1-yr, multicentre, randomised phase 2 dosage-finding study in the treatment of prostate cancer. Eur Urol. 2008;54(4):805-813.
(4) Doehn C. Immunotherapy of Prostate Cancer. Eur Urol. (2006);53-4:681-683.
SOURCE Ferring Pharmaceuticals Inc.