Table 1. Baseline and Demographic Characteristicsa.
| Characteristic | Zoledronic Acid Every 4 wk (n = 200) |
Zoledronic Acid Every 12 wk (n = 203) |
Placebo (n = 13) |
Total (N = 416) |
|---|---|---|---|---|
| Age, mean (SD), y | 59.2 (11.1) | 58.6 (11.2) | 60.8 (12.2) | 58.9 (11.1) |
| Age group, y | ||||
| <65 | 134 (67.0) | 148 (72.9) | 8 (61.5) | 290 (69.7) |
| ≥65 | 66 (33) | 55 (27.1) | 5 (38.5) | 126 (30.3) |
| Females | 200 (100) | 203 (100) | 13 (100) | 416 (100) |
| White | 173 (86.5) | 178 (87.7) | 13 (100) | 364 (87.5) |
| ECOG performance status | ||||
| 0-1 | 191 (95.5) | 195 (96.1) | 12 (92.3) | 398 (95.7) |
| ≥2 | 6 (3.0) | 6 (3.0) | 1 (7.7) | 13 (3.1) |
| Body mass index, mean (SD)b | 29.5 (6.2) (n = 177) |
29.7 (6.3) (n = 184) |
33.7 (8.6) (n = 12) |
29.7 (6.3) (n = 373) |
| BPI composite pain score, mean (SD) | 2.0 (1.9) (n = 176) |
2.2 (2.1) (n = 176) |
2.5 (1.7) (n = 12) |
2.14 (2.9) (n = 364) |
| Baseline serum creatinine | ||||
| Normal (<1.4 mg/dL) | 196 (98.0) | 192 (94.6) | 12 (92.3) | 400 (96.2) |
| Abnormal (≥1.4 mg/dL) | 2 (1.0) | 10 (4.9) | 1 (7.7) | 13 (3.1) |
| Duration of IV bisphosphonates prior to study, No. (%), mo | ||||
| >15 | 119 (59.5) | 106 (52.2) | 1 (7.7) | 226 (54.3) |
| ≤15 | 81 (40.5) | 97 (47.8) | 12 (92.3) | 190 (45.7) |
| uNTX:Cr ratio before studyc | ||||
| >100 | 9 (4.5) | 2 (1.0) | 11 (2.6) | |
| ≤100 | 191 (95.5) | 201 (99.0) | 13 (100) | 405 (97.4) |
| Time from initial diagnosis of cancer to randomization, wk | ||||
| Mean (SD) | 430 (334) (n = 199) |
369 (307) (n = 202) |
261 (291) (n = 13) |
395 (322) (n = 414) |
| Median (range) | 352 (48-1463) (n = 199) |
284 (44-1765) (n = 202) |
142 (62-885) (n = 13) |
296 (44-1765) (n = 414) |
Abbreviations: BPI, Brief Pain Inventory; ECOG, Eastern Cooperative Oncology Group; uNTX:Cr, urinary N-telopeptide to urinary creatinine.
SI conversion factors: To convert creatinine to micromoles per liter, multiply by 88.4.
Data are presented as number (percentage) of patients unless otherwise indicated. The study was designed to include a placebo arm, with a randomization ratio of 2:2:1 for zoledronic acid every 4 weeks, zoledronic acid every 12 weeks, and placebo. Consequently, 13 patients were randomly assigned to the placebo arm. Subsequently, with the approval of bisphosphonates, the placebo arm was eliminated. All patients who were randomly assigned to the placebo arm were switched to zoledronic acid every 4 weeks; their efficacy data were analyzed separately and were not reported in this article.
Body mass index was calculated as weight in kilograms divided by height in meters squared.
uNTX:Cr ratio is reported as nanomoles of bone collagen equivalent per millimoles of creatinine.