MedKoo product information:

Ozarelix

Ozarelix, a fourth generation GnRH antagonist, induces apoptosis in hormone refractory androgen receptor negative prostate cancer cells modulating expression and activity of death receptors.  Mechanistically, LHRH antagonists exert rapid inhibition of luteinizing hormone and follicle stimulating hormone with an accompanying rapid decrease in sex hormones and would therefore be expected to be effective in a variety of hormonally dependent disease states including ovarian cancer, prostate cancer, BPH, infertility, uterine myoma and endometriosis. BPH is a non-cancerous enlargement of the prostate that is caused by testosterone. Unlike LHRH agonists, ozarelix has the potential to reduce testosterone just enough to reduce both prostate size and symptoms without the severe side effects associated with a reduction in testosterone.

Current therapies for BPH either address its symptoms but not the underlying condition, or block growth of new prostate cells and reduce prostate size with only moderate relief of symptoms. There are two classes of drugs to treat BPH. The first, alpha-adrenergic receptor blockers, are believed to work by relaxing the smooth muscle in the urethra and bladder without addressing the underlying condition of the enlarged prostate. Drugs in the second category, 5-alpha reductase inhibitors, work by blocking production of the hormones that stimulate the growth of new prostate cells thereby stopping and eventually reversing enlargement of the prostate. This class of drugs has a slow onset of action, typically requiring daily treatment for many months before improving patient symptoms. Drugs in both classes can have significant side effects, including decreased libido, impotence, abnormal ejaculation, rhinitis, and cardiovascular effects such as dizziness, fainting and lightheadedness. See: http://www.spectrumpharm.com/ozarelix_SPI153.html.

According to news published in 27. January 2010,  Spectrum Pharmaceuticals  announced that it is discontinuing development of ozarelix in benign prostatic hypertrophy (BPH). “While ozarelix is a potent GnRH antagonist, low-dose intermittent therapy has been disappointing in the treatment of lower urinary tract symptoms in men with BPH. As a result, Spectrum Pharmaceuticals has made the strategic decision to discontinue the ozarelix BPH program”  said Rajesh C. Shrotriya, MD, Chairman, Chief Executive Officer, and President of Spectrum Pharmaceuticals.

Current developer:    Spectrum Pharmaceuticals, Inc

1: Festuccia C, Dondi D, Piccolella M, Locatelli A, Gravina GL, Tombolini V, Motta M. Ozarelix, a fourth generation GnRH antagonist, induces apoptosis in hormone refractory androgen receptor negative prostate cancer cells modulating expression and activity of death receptors. Prostate. 2010 Apr 5;70(12):1340-1349. [Epub ahead of print] PubMed PMID: 20623634.

2: Schneider A, Lang A, Naumann W. Fluorescence Spectroscopic Determination of the Critical Aggregation Concentration of the GnRH Antagonists Cetrorelix, Teverelix and Ozarelix. J Fluoresc. 2010 Jun 1. [Epub ahead of print] PubMed PMID: 20514551.

3: Bayés M, Rabasseda X, Prous JR. Gateways to clinical trials. Methods Find Exp Clin Pharmacol. 2007 Dec;29(10):697-735. PubMed PMID: 18200333.

4: Bayes M, Rabasseda X, Prous JR. Gateways to clinical trials. Methods Find Exp Clin Pharmacol. 2007 Oct;29(8):547-83. PubMed PMID: 18040531.