Pamidronate

What it is used for

Hypercalcemia of Malignancy Pamidronate disodium, in conjunction with adequate hydration, is indicated for the treatment of moderate or severe hypercalcemia associated with malignancy, with or without bone metastases. Patients who have either epidermoid or non-epidermoid tumors respond to treatment with pamidronate disodium.

Vigorous saline hydration, an integral part of hypercalcemia therapy, should be initiated promptly and an attempt should be made to restore the urine output to about 2 L/day throughout treatment. Mild or asymptomatic hypercalcemia may be treated with conservative measures (i.e., saline hydration, with or without loop diuretics).

Patients should be hydrated adequately throughout the treatment, but overhydration, especially in those patients who have cardiac failure, must be avoided. Diuretic therapy should not be employed prior to correction of hypovolemia. The safety and efficacy of pamidronate disodium in the treatment of hypercalcemia associated with hyperparathyroidism or with other non-tumor-related conditions has not been established.

Paget’s Disease Pamidronate disodium is indicated for the treatment of patients with moderate to severe Paget’s disease of bone. The effectiveness of pamidronate disodium was demonstrated primarily in patients with serum alkaline phosphatase ≥ 3 times the upper limit of normal. Pamidronate disodium therapy in patients with Paget’s disease has been effective in reducing serum alkaline phosphatase and urinary hydroxyproline levels by ≥ 50% in at least 50% of patients, and by ≥ 30% in at least 80% of patients.

Pamidronate disodium therapy has also been effective in reducing these biochemical markers in patients with Paget’s disease who failed to respond, or no longer responded to other treatments. Osteolytic Bone Metastases of Breast Cancer and Osteolytic Lesions of Multiple Myeloma Pamidronate disodium is indicated, in conjunction with standard antineoplastic therapy, for the treatment of osteolytic bone metastases of breast cancer and osteolytic lesions of multiple myeloma.

The pamidronate disodium treatment effect appeared to be smaller in the study of breast cancer patients receiving hormonal therapy than in the study of those receiving chemotherapy, however, overall evidence of clinical benefit has been demonstrated (see CLINICAL PHARMACOLOGY, Osteolytic Bone Metastases of Breast Cancer and Osteolytic Lesions of Multiple Myeloma, Clinical Trials section).

Side effects, and when to stop

The following adverse reactions are described, or described in greater detail, in other sections:

• Deterioration in renal function
• Electrolyte disorders
• Osteonecrosis of the jaw
• Atypical fractures of the femur

Who should not take it

Pamidronate disodium is contraindicated in patients with hypersensitivity to pamidronate disodium, other bisphosphonates, or mannitol. Reactions to pamidronate disodium injection and to mannitol have included anaphylaxis.