The purpose of this study is to compare the effect of an investigational drug used intravenously and placebo administered every three months for one year, on bone loss associated with initial androgen deprivation) in men with prostate cancer without metastasis. In order to participate in this trial male patients must be 18 years of age or older and have been diagnosed with prostate cancer without metastasis and within one year of starting their androgen deprivation therapy at the day of randomization onto this trial. In addition, patients who have undergone a recent orchiectomy (or"ke-ek'te-me) (removal of one or two testes) are eligible to participate.

Patients who received any prior bisphosphonate therapy or prior treatment with systemic corticosteroids within in the past 12 months are not eligible to participate. Also patients who are receiving treatment for osteoporosis are not eligible to participate.

Inclusion into this clinical trial with this investigational drug is based on the protocol entry criteria and evaluation from a participating trial investigator.

• Histologically confirmed diagnosis of carcinoma of the prostate
• No distant metastases (stage TNMO) (ie. prostate cancer without metastases)
• Patients within one year at the day of randomization from initiation of androgen deprivation therapy with a LHRH agonist (with or without an antiandrogen) and with the intended duration of androgen deprivation therapy of at least 12 months. Patients may also enter if they have received an orchiectomy (or"ke-ek'te-me) within two weeks of visit 1
• Patients who received any prior bisphosphonate therapy in the past 12 months will be excluded
• Patients who are currently receiving diethylstilbesterol (DES) or PC-SPES (treatment for osteoporosis) will be excluded
• Patients who have received prior treatment with systemic corticosteroids within the past 12 months will be excluded (short term corticosteroid therapy, e.g. to prevent/treat chemotherapy-induced nausea/vomiting or for acute illness like asthma exacerbation, is acceptable)
• Other eligibility criteria may apply