Efficacy and safety of zoledronic acid in patients with breast cancer metastatic to bone: a multicenter clinical trial.
OBJECTIVE
This study evaluated the efficacy and safety of zoledronic acid in breast cancer patients with newly diagnosed bone metastases.


METHODS
Patients diagnosed with bone metastases < or = 6 weeks prior to first visit were enrolled. Zoledronic acid (4 mg) was administered via a 15-minute infusion every 3 or 4 weeks for 12 infusions. Skeletal-related events (SREs) were defined as pathologic bone fractures, spinal cord compression, surgery to bone, radiation therapy to bone, and hypercalcemia of malignancy. Primary efficacy end points were the proportion of patients with at least one SRE and the time to first SRE. Secondary end points included pain, analgesic use, and quality of life.


RESULTS
Among 312 patients enrolled, 30% experienced at least one SRE during the 12-month study, and 22% experienced only one SRE. The median time to first SRE was not reached in the intent-to-treat population. Mean pain and analgesic scores declined from baseline, and quality-of-life scores remained stable to study end. The most frequently reported adverse events, regardless of relationship to study drug, were pyrexia (22%) and bone pain (10%). Serum creatinine levels did not significantly increase from baseline throughout the study.


CONCLUSIONS
Breast cancer patients with newly diagnosed bone metastases who were treated with zoledronic acid had a low incidence of SREs compared with patients who received placebo in randomized phase III trials, and pain was decreased from baseline. This study demonstrated the favorable risk:benefit ratio of zoledronic acid for the prevention of skeletal complications.
Cartenì
Giacomo
G
AORNA Cardarelli, Napoli, Italy.
Bordonaro
Roberto
R
Giotta
Francesco
F
Lorusso
Vito
V
Scalone
Simona
S
Vinaccia
Vincenza
V
Rondena
Roberta
R
Amadori
Dino
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D050071:Bone Density Conservation Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000556:secondary; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004164:Diphosphonates / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000009:adverse effects / Q000627:therapeutic use*; D007262:Infusions, Intravenous; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D015996:Survival Rate; D016896:Treatment Outcome; D000077211:Zoledronic Acid
D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D000077211:Zoledronic Acid