Special Populations
There are no data available on the effects of age, gender, or race on the pharmacokinetics of pamidronate.

Pediatric
Pamidronate is not labeled for use in the pediatric population.

Renal Insufficiency
The pharmacokinetics of pamidronate were studied in cancer patients (n=19) with normal and varying degrees of renal impairment. Each patient received a single 90 mg dose of pamidronate disodium infused over 4 hours. The renal clearance of pamidronate in patients was found to closely correlate with creatinine clearance (see Figure 1). A trend toward a lower percentage of drug excreted unchanged in urine was observed in renally impaired patients. Adverse experiences noted here not found to be related to changes in renal clearance of pamidronate. Given the recommended dose, 90 mg infused over 4 hours, excessive accumulation of pamidronate in renally impaired patients is not anticipated if pamidronate disodium is administered on a monthly basis.

Figure 1: Pamidronate renal clearance as a function of creatinine clearance in patients with normal and impaired renal function. The lines are the mean prediction line and 95% confidence intervals.

Hepatic Insufficiency
The pharmacokinetics of pamidronate were studied in male cancer patients at risk for bone metastases with normal hepatic function (n=6) and mild to moderate hepatic dysfunction (n=7). Each patient received a single 90 mg dose of pamidronate disodium infused over 4 hours. Although there was a statistically significant difference in the pharmacokinetics between patients with normal and impaired hepatic function, the difference was not considered clinically relevant. Patients with hepatic impairment exhibited higher mean AUC (53%) and Cmax (29%), and decreased plasma clearance (33%) values. Nevertheless, pamidronate was still rapidly cleared from the plasma. Drug levels were not detectable in patients by 12 to 36 hours after drug infusion. Because pamidronate disodium is administered on a monthly basis, drug accumulation is not expected. No changes in pamidronate disodium dosing regimen are recommended for patients with mild to moderate abnormal hepatic function. Pamidronate disodium has not been studied in patients with severe hepatic impairment.

Drug-Drug Interactions
There are no human pharmacokinetic data for drug interactions with pamidronate disodium.

Table 1 Mean (SD, CV%) Pamidronate Pharmacokinetic Parameters in Cancer Patients (n=6 for each group)  Dose

(infusion rate)
 Maximum Concentration

(mcg/mL)
 Percent of dose excreted in urine
 Total Clearance

(mL/min)
 Renal Clearance (mL/min)
 
30 mg
 0.73
 43.9
 136
 58
 
(4 hrs)
 (0.14, 19.1%)
 (14.0, 31.9%)
 (44, 32.4%)
 (27, 46.5%)
 
60 mg
 1.44
 47.4
 88
 42
 
(4 hrs)
 (0.57, 39.6%)
 (47.4, 54.4%)
 (56, 63.6%)
 (28, 66.7%)
 
90 mg
 2.61
 45.3
 103
 44
 
(4 hrs)
 (0.74, 28.3%)
 (25.8, 56.9%)
 (37, 35.9%)
 (16, 36.4%)
 
90 mg
 1.38
 47.5
 101
 52
 
(24 hrs)
 (1.97, 142.7%)
 (10.2, 21.5%)
 (58, 57.4%)
 (4