A Phase I Study of 1,25 Dihydroxy-Vitamin D3 (Calcitriol) in Patients With Prostate Cancer

Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed prior localized adenocarcinoma of the prostate that has
undergone definitive radiation or surgery and demonstrates progression biochemically
with all of the following:

- Baseline PSA at least 4 ng/mL

- At least a 50% increase in PSA over at least 3 determinations taken at more than
2 week intervals

- No radiographically evident disease

- Neoadjuvant hormonal therapy prior to radical prostatectomy or radiotherapy
allowed

- Treatment in an intermittent approach allowed if off therapy for at least 12
weeks OR

- Histologically confirmed androgen-independent adenocarcinoma of the prostate with all
of the following:

- Progression on primary hormonal treatment (e.g., orchiectomy, estrogen therapy,
gonadotropin-releasing hormone analog with or without an antiandrogen) with
either new osseous lesions in bone, a greater than 25% increase in
bidimensionally measurable tumor mass, or rising PSA values (rising PSA on any 3
determinations taken at at least weekly intervals, to greater than 50% above
baseline PSA) despite castrate levels of testosterone (no greater than 30 ng/mL)

- If receiving antiandrogen as part of primary hormonal therapy, must meet
criteria above for progression after discontinuation of antiandrogen

- No change in hormonal therapy (including prednisone or dexamethasone) within the
past 2 weeks

- If no prior surgical orchiectomy, must continue on medical therapies to maintain
castrate levels of testosterone

- Prior chemotherapy, palliative radiotherapy, or radioisotope treatment allowed

PATIENT CHARACTERISTICS:

Age:

- 18 and over

Performance status:

- Karnofsky 70-100%

Life expectancy:

- At least 3 months

Hematopoietic:

- WBC at least 3,500/mm^3

- Platelet count at least 100,000/mm^3

Hepatic:

- Bilirubin less than 2.0 mg/dL OR

- SGOT less than 3 times upper limit of normal

Renal:

- Creatinine less than 1.5 mg/dL OR

- Creatinine clearance at least 60 mL/min

- No history of nephrolithiasis

- Must have 2 functioning kidneys

Cardiovascular:

- No New York Heart Association class III or IV heart disease

Pulmonary:

- No severe debilitating pulmonary disease

Metabolic:

- No pre-existing endocrine or metabolic disorders that impact calcium regulatory axis
including hypercalcemia (ionized serum calcium greater than 5.3 mg/dL or total
calcium greater than 10.5 mg/dL) or hypercalciuria (greater than 300 mg urinary
calcium/24 hours)

Other:

- No active secondary malignancy except nonmelanoma skin cancer

- Must maintain low calcium diet (less than 800 mg calcium daily)

- No uncontrolled serious active infection

- No history of malabsorption disorders

- No history of inflammatory bowel disease

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- Not specified

Chemotherapy:

- See Disease Characteristics

- At least 4 weeks since prior chemotherapy and recovered

- No concurrent chemotherapy

Endocrine therapy:

- See Disease Characteristics

- Recovered from prior endocrine therapy

Radiotherapy:

- See Disease Characteristics

- At least 4 weeks since prior radiotherapy and recovered

- No concurrent radiotherapy to sole measurable lesion

Surgery:

- See Disease Characteristics

- Recovered from prior surgery

- No concurrent surgery to sole measurable lesion

Other:

- No other concurrent cholecalciferol