Benign Prostatic Hypertrophy (BPH) is a common and bothersome condition of aging men. It is characterized by an enlargement of the prostate occurring in human male over the age of 50 which increases in prevalence with age, and among those aged 50 to 80, about 40% report moderate or severe urinary symptoms of prostatism. The aim of treatment is to improve patients' quality of life which primarily depends on the severity of the symptoms of BPH. Current treatments of BPH have a benefit / risk ratio which leaves room for improvement.

For this study, study medication (Cetrorelix pamoate or placebo) is administered by injection in the buttocks (Intramuscular). All patients completing the double-blind portion (Week 0 to 52) are eligible to receive the active drug during the open-label part of the study (Week 52 to 90).

Inclusion Criteria:

• Benign Prostatic Hyperplasia, based on medical history
• Voiding symptoms

Exclusion Criteria:

• Urgent need for prostate surgery or prior surgical treatment of the prostate or bladder
• Major organ dysfunction
• Eczema (atopic dermatitis) treated during the last 6 months
• Current or recent treatment with sexual hormone drugs or 5 α reductase inhibitors or botulinum toxin type a (Botox) within the last 6 months prior randomization or with α blockers or saw palmetto within the last 6 weeks prior to randomization
• Urologic disorders including neurogenic bladder dysfunction due to diabetes mellitus or documented neurologic disorder, urethral stricture disease or history of pelvic radiation therapy
• History of acute obstructive, infectious, or neurological disorders of the genitourinary tract within the last 3 months