Paricalcitol in Treating Patients With Advanced Prostate Cancer and Bone Metastases

Inclusion:

Histologically or cytologically confirmed advanced adenocarcinoma of the prostate

- Radiographically proven bone metastasis from prostate cancer

Androgen refractory disease (including anti-androgen withdrawal)
Secondary hyperparathyroidism, defined as two parathyroid hormone (PTH) values > 70 pg/mL, 14 days apart
ECOG performance status 0-2
Leukocytes ≥ 3,000/μL
Absolute neutrophil count ≥ 1,500/μL
Platelets ≥ 100,000/μL
Total bilirubin normal
AST/ALT ≤ 2.5 times upper limit of normal
Creatinine clearance ≥ 60 mL/min
Calcium normal
25-hydroxyvitamin D (25-OHD) ≥ 20 ng/mL
1,25(OH)_2D normal
Patients with serum 25-OHD indicative of vitamin D insufficiency are eligible provided they are treated with ergocalciferol to raise 25-OHD levels to 20 ng/mL prior to paricalcitol therapy
More than 8 weeks since prior bisphosphonates
More than 2 weeks since prior palliative radiotherapy
More than 4 weeks since other prior therapy
No more than one prior taxane-containing chemotherapy regimen for metastatic disease
Multiple lines of prior therapy with hormonal agents allowed
Concurrent corticosteroids allowed provided the dose remains stable during the study period

Exclusion:

Underlying metabolic bone disease or vitamin D deficiency
History of hypercalcemia
Concurrent uncontrolled illness or co-morbid condition (including psychiatric illness) that would interfere with study compliance
Concurrent ergocalciferol supplementation
Concurrent chemotherapy or hormonal therapy
Concurrent investigational or commercial agents for the malignancy