Change in Corrected Serum Calcium by Time from Initiation of Treatment  *
Comparison between treatment groups
Time
 Mean Change from Baseline in Corrected Serum Calcium (mg/dL)
 
(hr)
Baseline
 Pamidronate Disodium
14.6
 Etidronate Disodium
13.8
 P-Value*
 
24
 -0.3
 -0.5
 
48
 -1.5
 -1.1
 
72
 -2.6
 -2.0
 
96
 -3.5
 -2.0
 <0.01
 
168
 -4.1
 -2.5
 <0.01
 

In a third multicenter, randomized, parallel double-blind trial, a group of 69 cancer patients with hypercalcemia was enrolled to receive 60 mg of pamidronate disodium as a 4 or 24 hour infusion, which was compared to a saline treatment group. Patients who had a corrected serum calcium level of ≥ 12 mg/dL after 24 hours of saline hydration were eligible for this trial.

The mean baseline-corrected serum calcium levels for pamidronate disodium 60 mg 4 hour infusion, pamidronate disodium 60 mg 24 hour infusion, and saline infusion were 14.2 mg/dL, 13.7 mg/dL, and 13.7 mg/dL, respectively.

By day 7 after initiation of treatment, 78%, 61%, and 22% of the patients had normal-corrected serum calcium levels for the 60 mg 4 hour infusion, 60 mg 24 hour infusion, and saline infusion, respectively. At day 14, 39% of the patients in the pamidronate disodium 60 mg 4 hour infusion group and 26% of the patients in the pamidronate disodium 60 mg 24 hour infusion group had normal-corrected serum calcium levels or maintenance of a partial response.

For responders, the median duration of complete responses was 4 days and 6.5 days for pamidronate disodium 60 mg 4 hour infusion and pamidronate disodium 60 mg 24 hour infusion, respectively.

In all three trials, patients treated with pamidronate disodium had similar response rates in the presence or absence of bone metastases. Concomitant administration of furosemide did not affect response rates.

Thirty-two patients who had recurrent or refractory hypercalcemia of malignancy were given a second course of 60 mg of pamidronate disodium over a 4 or 24 hour period. Of these, 41% showed a complete response and 16% showed a partial response to the retreatment, and these responders had about a 3 mg/dL fall in mean-corrected serum calcium levels 7 days after retreatment.

In a fourth multicenter, randomized, double-blind trial, 103 patients with cancer and hypercalcemia (corrected serum calcium ≥ 12 mg/dL) received 90 mg of pamidronate disodium as a 2 hour infusion. The mean baseline corrected serum calcium was 14 mg/dL. Patients were not required to receive IV hydration prior to drug administration, but all subjects did receive at least 500 mL of IV saline hydration concomitantly with the pamidronate infusion. By Day 10 after drug infusion, 70% of patients had normal corrected serum calcium levels (<10.8 mg/dL).

Paget’s Disease
Paget’s disease of bone (osteitis deformans) is an idiopathic disease characterized by chronic, focal areas of bone destruction complica