Paricalcitol in Treating Patients With Myelodysplastic Syndrome

A Phase II Trial Of Paricalcitol In Myelodysplastic Syndromes

RATIONALE: Paricalcitol is a form of vitamin D that may help myelodysplastic cells develop into normal bone marrow cells.

PURPOSE: Phase II trial to study the effectiveness of paricalcitol in treating patients who have myelodysplastic syndrome.

OBJECTIVES:

• Determine the clinical effects of paricalcitol in patients with myelodysplastic syndromes.
• Determine whether this drug can improve RBC, WBC, or platelet counts in these patients.
• Determine whether this drug can decrease the risk of development of leukemia without causing undue toxicity in these patients.

OUTLINE: Patients receive oral paricalcitol daily for 4 months in the absence of disease progression or unacceptable toxicity.

Patients are followed at 1 month.

PROJECTED ACCRUAL: A total of 20 patients will be accrued for this study within 8 months.

DISEASE CHARACTERISTICS:

• Clinical diagnosis of myelodysplastic syndromes according to the modified FAB classification

  • Confirmed by bone marrow aspiration showing blast and promyelocyte count no greater than 30% of the bone marrow differential

• Patients with refractory anemia with ringed sideroblasts are eligible provided there was no response to a 3-week course of prior high-dose pyridoxine

PATIENT CHARACTERISTICS:

Age

• 25 to 100

Performance status

• Karnofsky 60-100%

Life expectancy

• At least 12 weeks

Hematopoietic

• See Disease Characteristics

Hepatic

• Bilirubin less than 2.0 mg/dL

Renal

• Creatinine less than 2.5 mg/dL
• Calcium normal

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No prior sensitivity to paricalcitol or any component of its formulation
• No prior cholecalciferol toxicity
• No other concurrent acute illness

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Not specified

Chemotherapy

• More than 5 weeks since prior chemotherapy

Endocrine therapy

• Not specified

Radiotherapy

• More than 5 weeks since prior radiotherapy

Surgery

• Prior recent surgery allowed, if fully recovered

Other

• More than 5 weeks since prior megadose vitamins
• No concurrent cholecalciferol, phosphate, calcium, or cholestyramine
• No concurrent digoxin