Limitations of Use
The safety and efficacy of zoledronic acid injection in the treatment of hypercalcemia associated with hyperparathyroidism or with other non-tumor-related conditions have not been established.
4 mg/5 mL Single-Dose Vial for Dilution Prior to Intravenous Infusion
Zoledronic acid injection 4 mg/5 mL vial for dilution prior to intravenous infusion contains an overfill to allow withdrawal of 5 mL (equivalent to 4 mg zoledronic acid). Zoledronic acid injection (4 mg/5 mL) should immediately be diluted in 100 mL of sterile 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP, following proper aseptic technique, and administered to the patient by intravenous infusion. Do not store undiluted zoledronic acid injection (4 mg/5 mL) in a syringe, to avoid inadvertent injection.
To prepare reduced doses for patients with baseline CrCl less than or equal to 60 mL/min, withdraw the specified volume of the zoledronic acid injection (4 mg/5 mL) from the vial for the dose required (see Table 3).
Table 3: Preparation of Reduced Doses - Zoledronic Acid Injection 4 mg/5 mL Single-Dose Vial for Dilution| Remove and Use Zoledronic Acid Injection Volume (mL) | Dose (mg) |
|---|
| 4.4 | 3.5 |
| 4.1 | 3.3 |
| 3.8 | 3.0 |
The withdrawn zoledronic acid injection (4 mg/5 mL) solution must be diluted in 100 mL of sterile 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP.
If not used immediately after dilution with infusion media, for microbiological integrity, the solution should be refrigerated at 2°C to 8°C (36°F to 46°F). The refrigerated solution should then be equilibrated to room temperature prior to administration. The total time between dilution, storage in the refrigerator, and end of administration must not exceed 24 hours.
Hypersensitivity to Zoledronic Acid or Any Components of Zoledronic Acid Injection
Hypersensitivity reactions including rare cases of urticaria and angioedema, and very rare cases of anaphylactic reaction/shock have been reported [see Adverse Reactions (6.2)].
Hypercalcemia of Malignancy
The safety of zoledronic acid injection was studied in 185 patients with hypercalcemia of malignancy (HCM) who received either zoledronic acid injection 4 mg given as a 5-minute intravenous infusion (n=86) or pamidronate 90 mg given as a 2-hour intravenous infusion (n=103). The population was aged 33-84 years, 60% male and 81% Caucasian, with breast, lung, head and neck, and renal cancer as the most common forms of malignancy. NOTE: pamidronate 90 mg was given as a 2-hour intravenous infusion. The relative safety of pamidronate 90 mg given as a 2-hour intravenous infusion compared to the same dose given as a 24-hour intravenous infusion has not been adequately studied in controlled clinical trials.
Renal Toxicity
Administration of zoledronic acid injection 4 mg given as a 5-minute intravenous infusion has been shown to result in an increased risk of renal toxicity, as measured by increases in serum creatinine, which can progress to renal failure. The incidence of renal toxicity and renal failure has been shown to be reduced when zoledronic acid injection 4 mg is given as a 15-minute intravenous infusion. Zoledronic acid injection should be administered by intravenous infusion over no less than 15 minutes [see Warnings and Precautions (5.3), Dosage and Administration (2.4)].
The most frequently observed adverse events were fever, nausea, constipation, anemia, and dyspnea (see Table 4).
Table 4 provides adverse events that were reported by 10% or more of the 189 patients treated with zoledronic acid injection 4 mg or pamidronate 90 mg from the two HCM trials. Adverse events are listed regardless of presumed causality to study drug.
Table 4: Percentage of Patients With Adverse Events Greater Than or Equal to 10% Reported in Hypercalcemia of Malignancy Clinical Trials by Body System | Zoledronic Acid Injection 4 mg n (%) | | Pamidronate 90 mg n (%) |
|---|
| Patients Studied |
| Total No. of Patients Studied | 86 | (100) | | 103 | (100) |
| Total No. of Patients with any AE | 81 | (94) | | 95 | (92) |
| Body as a Whole |
| Fever | 38 | (44) | | 34 | (33) |
| Progression of Cancer | 14 | (16) | | 21 | (20) |
| Cardiovascular |
| Hypotension | 9 | (11) | | 2 | (2) |
| Digestive |
| Nausea | 25 | (29) | | 28 | (27) |
| Constipation | 23 | (27) | | 13 | (13) |
| Diarrhea | 15 | (17) | | 17 | (17) |
| Abdominal Pain | 14 | (16) | | 13 | (13) |
| Vomiting | 12 | (14) | | 17 | (17) |
| Anorexia | 8 | (9) | | 14 | (14) |
| Hemic and Lymphatic System |
| Anemia | 19 | (22) | | 18 | (18) |
| Infections |
| Moniliasis | 10 | (12) | | 4 | (4) |
| Laboratory Abnormalities |
| Hypophosphatemia | 11 | (13) | | 2 | (2) |
| Hypokalemia | 10 | (12) | | 16 | (16) |
| Hypomagnesemia | 9 | (11) | | 5 | (5) |
| Musculoskeletal |
| Skeletal Pain | 10 | (12) | | 10 | (10) |
| Nervous |
| Insomnia | 13 | (15) | | 10 | (10) |
| Anxiety | 12 | (14) | | 8 | (8) |
| Confusion | 11 | (13) | | 13 | (13) |
| Agitation | 11 | (13) | | 8 | (8) |
| Respiratory |
| Dyspnea | 19 | (22) | | 20 | (19) |
| Coughing | 10 | (12) | | 12 | (12) |
| Urogenital |
| Urinary Tract Infection | 12 | (14) | | 15 | (15) |
The following adverse events from the two controlled multicenter HCM trials (n=189) were reported by a greater percentage of patients treated with zoledronic acid injection 4 mg than with pamidronate 90 mg and occurred with a frequency of greater than or equal to 5% but less than 10%. Adverse events are listed regardless of presumed causality to study drug: asthenia, chest pain, leg edema, mucositis, dysphagia, granulocytopenia, thrombocytopenia, pancytopenia, nonspecific infection, hypocalcemia, dehydration, arthralgias, headache and somnolence.
Rare cases of rash, pruritus, and chest pain have been reported following treatment with zoledronic acid injection.
Acute Phase Reaction
Within three days after zoledronic acid injection administration, an acute phase reaction has been reported in patients, with symptoms including pyrexia, fatigue, bone pain and/or arthralgias, myalgias, chills, and influenza-like illness. These symptoms usually resolve within a few days. Pyrexia has been the most commonly associated symptom, occurring in 44% of patients.
Mineral and Electrolyte Abnormalities
Electrolyte abnormalities, most commonly hypocalcemia, hypophosphatemia and hypomagnesemia, can occur with bisphosphonate use.
Grade 3 and Grade 4 laboratory abnormalities for serum creatinine, serum calcium, serum phosphorus, and serum magnesium observed in two clinical trials of zoledronic acid injection in patients with HCM are shown in Table 5 and 6.
Table 5: Grade 3 Laboratory Abnormalities for Serum Creatinine, Serum Calcium, Serum Phosphorus, and Serum Magnesium in Two Clinical Trials in Patients With HCM | | | Grade 3 | | |
|---|
| Laboratory Parameter | Zoledronic Acid Injection 4 mg | | Pamidronate 90 mg |
|---|
| n/N | (%) | | n/N | (%) |
|---|
| Serum Creatinine Grade 3 (greater than 3× Upper Limit of Normal); Grade 4 (greater than 6× Upper Limit of Normal). | 2/86 | (2%) | | 3/100 | (3%) |
| Hypocalcemia Grade 3 (less than 7 mg/dL); Grade 4 (less than 6 mg/dL). | 1/86 | (1%) | | 2/100 | (2%) |
| Hypophosphatemia Grade 3 (less than 2 mg/dL); Grade 4 (less than 1 mg/dL). | 36/70 | (51%) | | 27/81 | (33%) |
| Hypomagnesemia Grade 3 (less than 0.8 mEq/L); Grade 4 (less than 0.5 mEq/L). | 0/71 | 0 | | 0/84 | 0 |
Table 6: Grade 4 Laboratory Abnormalities for Serum Creatinine, Serum Calcium, Serum Phosphorus, and Serum Magnesium in Two Clinical Trials in Patients With HCM | | | Grade 4 | | |
|---|
| Laboratory Parameter | Zoledronic Acid Injection 4 mg | | Pamidronate 90 mg |
|---|
| n/N | (%) | | n/N | (%) |
|---|
| Serum Creatinine Grade 3 (greater than 3× Upper Limit of Normal); Grade 4 (greater than 6× Upper Limit of Normal). | 0/86 | 0 | | 1/100 | (1%) |
| Hypocalcemia Grade 3 (less than 7 mg/dL); Grade 4 (less than 6 mg/dL). | 0/86 | 0 | | 0/100 | 0 |
| Hypophosphatemia Grade 3 (less than 2 mg/dL); Grade 4 (less than 1 mg/dL). | 1/70 | (1%) | | 4/81 | (5%) |
| Hypomagnesemia Grade 3 (less than 0.8 mEq/L); Grade 4 (less than 0.5 mEq/L). | 0/71 | 0 | | 1/84 | (1%) |
Injection-Site Reactions
Local reactions at the infusion-site, such as redness or swelling, were observed infrequently. In most cases, no specific treatment is required and the symptoms subside after 24-48 hours.
Ocular Adverse Events
Ocular inflammation such as uveitis and scleritis can occur with bisphosphonate use, including zoledronic acid injection. No cases of iritis, scleritis or uveitis were reported during these clinical trials. However, cases have been seen in postmarketing use [see Adverse Reactions (6.2)].
Multiple Myeloma and Bone Metastases of Solid Tumors
The safety analysis includes patients treated in the core and extension phases of the trials. The analysis includes the 2042 patients treated with zoledronic acid injection 4 mg, pamidronate 90 mg, or placebo in the three controlled multicenter bone metastases trials, including 969 patients completing the efficacy phase of the trial, and 619 patients that continued in the safety extension phase. Only 347 patients completed the extension phases and were followed for 2 years (or 21 months for the other solid tumor patients). The median duration of exposure for safety analysis for zoledronic acid injection 4 mg (core plus extension phases) was 12.8 months for breast cancer and multiple myeloma, 10.8 months for prostate cancer, and 4.0 months for other solid tumors.
Table 7 describes adverse events that were reported by 10% or more of patients. Adverse events are listed regardless of presumed causality to study drug.
Table 7: Percentage of Patients With Adverse Events Greater Than or Equal to 10% Reported in Three Bone Metastases Clinical Trials by Body System | Zoledronic Acid Injection | Pamidronate | Placebo |
|---|
| 4 mg n (%) | 90 mg n (%) | n (%) |
|---|
| Patients Studied |
| Total No. of Patients | 1031 | (100) | 556 | (100) | 455 | (100) |
| Total No. of Patients with any AE | 1015 | (98) | 548 | (99) | 445 | (98) |
| Blood and Lymphatic |
| Anemia | 344 | (33) | 175 | (32) | 128 | (28) |
| Neutropenia | 124 | (12) | 83 | (15) | 35 | (8) |
| Thrombocytopenia | 102 | (10) | 53 | (10) | 20 | (4) |
| Gastrointestinal |
| Nausea | 476 | (46) | 266 | (48) | 171 | (38) |
| Vomiting | 333 | (32) | 183 | (33) | 122 | (27) |
| Constipation | 320 | (31) | 162 | (29) | 174 | (38) |
| Diarrhea | 249 | (24) | 162 | (29) | 83 | (18) |
| Abdominal Pain | 143 | (14) | 81 | (15) | 48 | (11) |
| Dyspepsia | 105 | (10) | 74 | (13) | 31 | (7) |
| Stomatitis | 86 | (8) | 65 | (12) | 14 | (3) |
| Sore Throat | 82 | (8) | 61 | (11) | 17 | (4) |
| General Disorders and Administration Site |
| Fatigue | 398 | (39) | 240 | (43) | 130 | (29) |
| Pyrexia | 328 | (32) | 172 | (31) | 89 | (20) |
| Weakness | 252 | (24) | 108 | (19) | 114 | (25) |
| Edema Lower Limb | 215 | (21) | 126 | (23) | 84 | (19) |
| Rigors | 112 | (11) | 62 | (11) | 28 | (6) |
| Infections |
| Urinary Tract Infection | 124 | (12) | 50 | (9) | 41 | (9) |
| Upper Respiratory Tract Infection | 101 | (10) | 82 | (15) | 30 | (7) |
| Metabolism |
| Anorexia | 231 | (22) | 81 | (15) | 105 | (23) |
| Weight Decreased | 164 | (16) | 50 | (9) | 61 | (13) |
| Dehydration | 145 | (14) | 60 | (11) | 59 | (13) |
| Appetite Decreased | 130 | (13) | 48 | (9) | 45 | (10) |
| Musculoskeletal |
| Bone Pain | 569 | (55) | 316 | (57) | 284 | (62) |
| Myalgia | 239 | (23) | 143 | (26) | 74 | (16) |
| Arthralgia | 216 | (21) | 131 | (24) | 73 | (16) |
| Back Pain | 156 | (15) | 106 | (19) | 40 | (9) |
| Pain in Limb | 143 | (14) | 84 | (15) | 52 | (11) |
| Neoplasms |
| Malignant Neoplasm Aggravated | 205 | (20) | 97 | (17) | 89 | (20) |
| Nervous |
| Headache | 191 | (19) | 149 | (27) | 50 | (11) |
| Dizziness (excluding vertigo) | 180 | (18) | 91 | (16) | 58 | (13) |
| Insomnia | 166 | (16) | 111 | (20) | 73 | (16) |
| Paresthesia | 149 | (15) | 85 | (15) | 35 | (8) |
| Hypoesthesia | 127 | (12) | 65 | (12) | 43 | (10) |
| Psychiatric |
| Depression | 146 | (14) | 95 | (17) | 49 | (11) |
| Anxiety | 112 | (11) | 73 | (13) | 37 | (8) |
| Confusion | 74 | (7) | 39 | (7) | 47 | (10) |
| Respiratory |
| Dyspnea | 282 | (27) | 155 | (28) | 107 | (24) |
| Cough | 224 | (22) | 129 | (23) | 65 | (14) |
| Skin |
| Alopecia | 125 | (12) | 80 | (14) | 36 | (8) |
| Dermatitis | 114 | (11) | 74 | (13) | 38 | (8) |
Grade 3 and Grade 4 laboratory abnormalities for serum creatinine, serum calcium, serum phosphorus, and serum magnesium observed in three clinical trials of zoledronic acid injection in patients with bone metastases are shown in Tables 8 and 9.
Table 8: Grade 3 Laboratory Abnormalities for Serum Creatinine, Serum Calcium, Serum Phosphorus, and Serum Magnesium in Three Clinical Trials in Patients With Bone Metastases | | Grade 3 | |
|---|
| Laboratory Parameter | Zoledronic Acid Injection 4 mg | Pamidronate 90 mg | Placebo |
|---|
| n/N | (%) | n/N | (%) | n/N | (%) |
|---|
| Serum Creatinine Grade 3 (greater than 3× Upper Limit of Normal); Grade 4 (greater than 6× Upper Limit of Normal). Serum creatinine data for all patients randomized after the 15-minute infusion amendment. | 7/529 | (1%) | 4/268 | (2%) | 4/241 | (2%) |
| Hypocalcemia Grade 3 (less than 7 mg/dL); Grade 4 (less than 6 mg/dL). | 6/973 | (<1%) | 4/536 | (<1%) | 0/415 | 0 |
| Hypophosphatemia Grade 3 (less than 2 mg/dL); Grade 4 (less than 1 mg/dL). | 115/973 | (12%) | 38/537 | (7%) | 14/415 | (3%) |
| Hypermagnesemia Grade 3 (greater than 3 mEq/L); Grade 4 (greater than 8 mEq/L). | 19/971 | (2%) | 2/535 | (<1%) | 8/415 | (2%) |
| Hypomagnesemia Grade 3 (less than 0.9 mEq/L); Grade 4 (less than 0.7 mEq/L). | 1/971 | (<1%) | 0/535 | - | 1/415 | (<1%) |
Table 9: Grade 4 Laboratory Abnormalities for Serum Creatinine, Serum Calcium, Serum Phosphorus, and Serum Magnesium in Three Clinical Trials in Patients With Bone Metastases | | Grade 4 | |
|---|
| Laboratory Parameter | Zoledronic Acid Injection 4 mg | Pamidronate 90 mg | Placebo |
|---|
| n/N | (%) | n/N | (%) | n/N | (%) |
|---|
| Serum Creatinine Grade 3 (greater than 3× Upper Limit of Normal); Grade 4 (greater than 6× Upper Limit of Normal). Serum creatinine data for all patients randomized after the 15-minute infusion amendment. | 2/529 | (<1%) | 1/268 | (<1%) | 0/241 | 0 |
| Hypocalcemia Grade 3 (less than 7 mg/dL); Grade 4 (less than 6 mg/dL). | 7/973 | (<1%) | 3/536 | (<1%) | 2/415 | (<1%) |
| Hypophosphatemia Grade 3 (less than 2 mg/dL); Grade 4 (less than 1 mg/dL). | 5/973 | (<1%) | 0/537 | 0 | 1/415 | (<1%) |
| Hypermagnesemia Grade 3 (greater than 3 mEq/L); Grade 4 (greater than 8 mEq/L). | 0/971 | 0 | 0/535 | 0 | 2/415 | (<1%) |
| Hypomagnesemia Grade 3 (less than 0.9 mEq/L); Grade 4 (less than 0.7 mEq/L). | 2/971 | (<1%) | 1/535 | (<1%) | 0/415 | 0 |
Among the less frequently occurring adverse events (less than 15% of patients), rigors, hypokalemia, influenza-like illness, and hypocalcemia showed a trend for more events with bisphosphonate administration (zoledronic acid injection 4 mg and pamidronate groups) compared to the placebo group.
Less common adverse events reported more often with zoledronic acid injection 4 mg than pamidronate included decreased weight, which was reported in 16% of patients in the zoledronic acid injection 4 mg group compared with 9% in the pamidronate group. Decreased appetite was reported in slightly more patients in the zoledronic acid injection 4 mg group (13%) compared with the pamidronate (9%) and placebo (10%) groups, but the clinical significance of these small differences is not clear.
Renal Toxicity
In the bone metastases trials, renal deterioration was defined as an increase of 0.5 mg/dL for patients with normal baseline creatinine (less than 1.4 mg/dL) or an increase of 1.0 mg/dL for patients with an abnormal baseline creatinine (greater than or equal to 1.4 mg/dL). The following are data on the incidence of renal deterioration in patients receiving zoledronic acid injection 4 mg over 15 minutes in these trials (see Table 10).
Table 10: Percentage of Patients With Treatment Emergent Renal Function Deterioration by Baseline Serum CreatinineTable includes only patients who were randomized to the trial after a protocol amendment that lengthened the infusion duration of zoledronic acid injection to 15 minutes.
| Patient Population/Baseline Creatinine | | | | |
|---|
| Multiple Myeloma and Breast Cancer | Zoledronic Acid Injection 4 mg | Pamidronate 90 mg |
| n/N | (%) | n/N | (%) |
| Normal | 27/246 | (11%) | 23/246 | (9%) |
| Abnormal | 2/26 | (8%) | 2/22 | (9%) |
| Total | 29/272 | (11%) | 25/268 | (9%) |
| Solid Tumors | Zoledronic Acid Injection 4 mg | Placebo |
| n/N | (%) | n/N | (%) |
| Normal | 17/154 | (11%) | 10/143 | (7%) |
| Abnormal | 1/11 | (9%) | 1/20 | (5%) |
| Total | 18/165 | (11%) | 11/163 | (7%) |
| Prostate Cancer | Zoledronic Acid Injection 4 mg | Placebo |
| n/N | (%) | n/N | (%) |
| Normal | 12/82 | (15%) | 8/68 | (12%) |
| Abnormal | 4/10 | (40%) | 2/10 | (20%) |
| Total | 16/92 | (17%) | 10/78 | (13%) |
The risk of deterioration in renal function appeared to be related to time on study, whether patients were receiving zoledronic acid injection (4 mg over 15 minutes), placebo, or pamidronate.
In the trials and in postmarketing experience, renal deterioration, progression to renal failure, and dialysis have occurred in patients with normal and abnormal baseline renal function, including patients treated with 4 mg infused over a 15-minute period. There have been instances of this occurring after the initial zoledronic acid injection dose.
Osteonecrosis of the Jaw
Cases of osteonecrosis (primarily involving the jaw but also of other anatomical sites including hip, femur and external auditory canal) have been reported predominantly in cancer patients treated with intravenous bisphosphonates including zoledronic acid injection. Many of these patients were also receiving chemotherapy and corticosteroids which may be a risk factor for ONJ. Caution is advised when zoledronic acid injection is administered with anti-angiogenic drugs as an increased incidence of ONJ has been observed with concomitant use of these drugs. Data suggests a greater frequency of reports of ONJ in certain cancers, such as advanced breast cancer and multiple myeloma. The majority of the reported cases are in cancer patients following invasive dental procedures, such as tooth extraction. It is therefore prudent to avoid invasive dental procedures as recovery may be prolonged [see Warnings and Precautions (5.4)].
Acute Phase Reaction
Within three days after zoledronic acid injection administration, an acute phase reaction has been reported, with symptoms including pyrexia, fatigue, bone pain and/or arthralgias, myalgias, chills, influenza-like illness and arthritis with subsequent joint swelling; these symptoms usually resolve within three days of onset, but resolution could take up to 7 to 14 days. However, some of these symptoms have been reported to persist for a longer duration.
Musculoskeletal Pain
Severe and occasionally incapacitating bone, joint, and/or muscle pain has been reported with bisphosphonate use [see Warnings and Precautions (5.5)].
Atypical Subtrochanteric and Diaphyseal Femoral Fractures
Atypical subtrochanteric and diaphyseal femoral fractures have been reported with bisphosphonate therapy, including zoledronic acid injection [see Warnings and Precautions (5.6)].
Ocular Adverse Events
Cases of uveitis, scleritis, episcleritis, conjunctivitis, iritis, and orbital inflammation including orbital edema have been reported during postmarketing use. In some cases, symptoms resolved with topical steroids.
Hypersensitivity Reactions
There have been rare reports of allergic reaction with intravenous zoledronic acid including angioedema, and bronchoconstriction. Very rare cases of anaphylactic reaction/shock have been reported. Cases of Stevens-Johnson syndrome and toxic epidermal necrolysis have also been reported.
Additional adverse reactions reported in postmarketing use include:
CNS: taste disturbance, hyperesthesia, tremor; Special Senses: blurred vision; uveitis; Gastrointestinal: dry mouth; Skin: Increased sweating; Musculoskeletal: muscle cramps; Cardiovascular: hypertension, bradycardia, hypotension (associated with syncope or circulatory collapse primarily in patients with underlying risk factors); Respiratory: bronchospasms, interstitial lung disease (ILD) with positive rechallenge; Renal: hematuria, proteinuria, acquired Fanconi syndrome; General Disorders and Administration Site: weight increase, influenza-like illness (pyrexia, asthenia, fatigue or malaise) persisting for greater than 30 days; Laboratory Abnormalities: hyperkalemia, hypernatremia, hypocalcemia (cardiac arrhythmias and neurologic adverse events including seizures, tetany, and numbness have been reported due to severe hypocalcemia).
Risk Summary
Based on findings from animal studies and its mechanism of action, zoledronic acid injection can cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology (12.1)]. There are no available data in pregnant women to inform the drug-associated risk. In animal reproduction studies, administration of zoledronic acid to pregnant rats during organogenesis resulted in fetal malformations and embryo-fetal lethality at maternal exposures that were ≥ 2.4 times the human clinical exposure based on AUC (see Data). Bisphosphonates, such as zoledronic acid, are incorporated into the bone matrix, from where they are gradually released over periods of weeks to years. There may be a risk of fetal harm (e.g., skeletal and other abnormalities) if a woman becomes pregnant after completing a course of bisphosphonate therapy. Advise pregnant women and females of reproductive potential of the potential risk to a fetus.
The background risk of major birth defects and miscarriage for the indicated population is unknown; however, in the U.S. general population, the estimated background risk of major birth defects is 2%-4% and of miscarriage is 15%-20% of clinically recognized pregnancies.
Data
Animal Data
In female rats given subcutaneous doses of zoledronic acid of 0.01, 0.03, or 0.1 mg/kg/day beginning 15 days before mating and continuing through gestation, the number of stillbirths was increased and survival of neonates was decreased in the mid- and high-dose groups (greater than or equal to 0.2 times the human systemic exposure following an intravenous dose of 4 mg, based on an AUC comparison). Adverse maternal effects were observed in all dose groups (with a systemic exposure of greater than or equal to 0.07 times the human systemic exposure following an intravenous dose of 4 mg, based on an AUC comparison) and included dystocia and periparturient mortality in pregnant rats allowed to deliver. Maternal mortality may have been related to drug-induced inhibition of skeletal calcium mobilization, resulting in periparturient hypocalcemia. This appears to be a bisphosphonate-class effect.
In pregnant rats given a subcutaneous dose of zoledronic acid of 0.1, 0.2, or 0.4 mg/kg/day during gestation, adverse fetal effects were observed in the mid- and high-dose groups (with systemic exposures of 2.4 and 4.8 times, respectively, the human systemic exposure following an intravenous dose of 4 mg, based on an AUC comparison). These adverse effects included increases in pre- and postimplantation losses, decreases in viable fetuses, and fetal skeletal, visceral, and external malformations. Fetal skeletal effects observed in the high-dose group included unossified or incompletely ossified bones, thickened, curved, or shortened bones, wavy ribs, and shortened jaw. Other adverse fetal effects observed in the high-dose group included reduced lens, rudimentary cerebellum, reduction or absence of liver lobes, reduction of lung lobes, vessel dilation, cleft palate, and edema. Skeletal variations were also observed in the low-dose group at 0.1 mg/kg/day (with systemic exposure of 1.2 times the human systemic exposure following an intravenous dose of 4 mg, based on an AUC comparison). Signs of maternal toxicity were observed in the high-dose group and included reduced body weights and food consumption, indicating that maximal exposure levels were achieved in this study.
In pregnant rabbits given subcutaneous doses of zoledronic acid of 0.01, 0.03, or 0.1 mg/kg/day during gestation (less than or equal to 0.5 times the human intravenous dose of 4 mg, based on a comparison of relative body surface areas), no adverse fetal effects were observed. Maternal mortality and abortion occurred in all treatment groups (at doses greater than or equal to 0.05 times the human intravenous dose of 4 mg, based on a comparison of relative body surface areas). Adverse maternal effects were associated with, and may have been caused by, drug-induced hypocalcemia.
Risk Summary
After administration of zoledronic acid injection, it is not known whether zoledronic acid is present in human milk, or whether it affects milk production or the breastfed child. Zoledronic acid binds to bone long term and may be released over periods of weeks to years. Because of the potential for serious adverse reactions in a breastfed child, advise a lactating woman not to breastfeed during and after zoledronic acid injection treatment.
Pregnancy Testing
Verify pregnancy status of females of reproductive potential prior to initiation of zoledronic acid injection.
Contraception
Females
Zoledronic acid injection can cause fetal harm when administered to a pregnant woman [see Use in Specific Populations (8.1)]. Zoledronic acid binds to bone long term and may be released over periods of weeks to years. Advise females of reproductive potential to use effective contraception during and after zoledronic acid injection treatment.
Infertility
Females
Based on animal studies, zoledronic acid injection may impair fertility in females of reproductive potential [see Nonclinical Toxicology (13.1)].
Distribution
Single or multiple (every 28 days) 5-minute or 15-minute infusions of 2, 4, 8, or 16 mg zoledronic acid injection were given to 64 patients with cancer and bone metastases. The postinfusion decline of zoledronic acid concentrations in plasma was consistent with a triphasic process showing a rapid decrease from peak concentrations at end of infusion to less than 1% of Cmax 24 hours postinfusion with population half-lives of t1/2α 0.24 hours and t1/2β 1.87 hours for the early disposition phases of the drug. The terminal elimination phase of zoledronic acid was prolonged, with very low concentrations in plasma between Days 2 and 28 postinfusion, and a terminal elimination half-life t1/2γ of 146 hours. The area under the plasma concentration versus time curve (AUC0-24h) of zoledronic acid was dose proportional from 2-16 mg. The accumulation of zoledronic acid measured over three cycles was low, with mean AUC0-24h ratios for cycles 2 and 3 versus 1 of 1.13 ± 0.30 and 1.16 ± 0.36, respectively.
In vitro and ex vivo studies showed low affinity of zoledronic acid for the cellular components of human blood, with a mean blood to plasma concentration ratio of 0.59 in a concentration range of 30 ng/mL to 5000 ng/mL. In vitro, the plasma protein binding is low, with the unbound fraction ranging from 60% at 2 ng/mL to 77% at 2000 ng/mL of zoledronic acid.
Metabolism
Zoledronic acid does not inhibit human P450 enzymes in vitro. Zoledronic acid does not undergo biotransformation in vivo. In animal studies, less than 3% of the administered intravenous dose was found in the feces, with the balance either recovered in the urine or taken up by bone, indicating that the drug is eliminated intact via the kidney. Following an intravenous dose of 20 nCi 14C-zoledronic acid in a patient with cancer and bone metastases, only a single radioactive species with chromatographic properties identical to those of parent drug was recovered in urine, which suggests that zoledronic acid is not metabolized.
Excretion
In 64 patients with cancer and bone metastases, on average (± SD) 39 ± 16% of the administered zoledronic acid dose was recovered in the urine within 24 hours, with only trace amounts of drug found in urine post-Day 2. The cumulative percent of drug excreted in the urine over 0-24 hours was independent of dose. The balance of drug not recovered in urine over 0-24 hours, representing drug presumably bound to bone, is slowly released back into the systemic circulation, giving rise to the observed prolonged low plasma concentrations. The 0-24 hour renal clearance of zoledronic acid was 3.7 ± 2.0 L/h.
Zoledronic acid clearance was independent of dose but dependent upon the patient's creatinine clearance. In a study in patients with cancer and bone metastases, increasing the infusion time of a 4-mg dose of zoledronic acid from 5 minutes (n=5) to 15 minutes (n=7) resulted in a 34% decrease in the zoledronic acid concentration at the end of the infusion ([mean ± SD] 403 ± 118 ng/mL versus 264 ± 86 ng/mL) and a 10% increase in the total AUC (378 ± 116 ng × h/mL versus 420 ± 218 ng × h/mL). The difference between the AUC means was not statistically significant.
Special Populations
Pediatrics
Zoledronic acid injection is not indicated for use in children [see Use in Specific Populations (8.4)].
Geriatrics
The pharmacokinetics of zoledronic acid were not affected by age in patients with cancer and bone metastases who ranged in age from 38 years to 84 years.
Race
Population pharmacokinetic analyses did not indicate any differences in pharmacokinetics among Japanese and North American (Caucasian and African American) patients with cancer and bone metastases.
Hepatic Insufficiency
No clinical studies were conducted to evaluate the effect of hepatic impairment on the pharmacokinetics of zoledronic acid.
Renal Insufficiency
The pharmacokinetic studies conducted in 64 cancer patients represented typical clinical populations with normal to moderately impaired renal function. Compared to patients with normal renal function (N=37), patients with mild renal impairment (N=15) showed an average increase in plasma AUC of 15%, whereas patients with moderate renal impairment (N=11) showed an average increase in plasma AUC of 43%. Limited pharmacokinetic data are available for zoledronic acid injection in patients with severe renal impairment (creatinine clearance less than 30 mL/min). Based on population PK/PD modeling, the risk of renal deterioration appears to increase with AUC, which is doubled at a creatinine clearance of 10 mL/min. Creatinine clearance is calculated by the Cockcroft-Gault formula:
| CrCl = | [140-age (years)] × weight (kg) {× 0.85 for female patients} |
| [72 × serum creatinine (mg/dL)] |
Zoledronic acid injection systemic clearance in individual patients can be calculated from the population clearance of zoledronic acid injection, CL (L/h) = 6.5(CrCl/90)0.4. These formulae can be used to predict the zoledronic acid injection AUC in patients, where CL = Dose/AUC0-∞. The average AUC0-24 in patients with normal renal function was 0.42 mg∙h/L and the calculated AUC0-∞ for a patient with creatinine clearance of 75 mL/min was 0.66 mg∙h/L following a 4-mg dose of zoledronic acid injection. However, efficacy and safety of adjusted dosing based on these formulae have not been prospectively assessed [see Warnings and Precautions (5.3)].
Drugs With Same Active Ingredient or in the Same Drug Class
Inform patients not to take Reclast or other bisphosphonates during the course of their zoledronic acid injection therapy [see Warnings and Precautions (5.1)].
Renal Impairment
- Instruct patients to tell their doctor if they have kidney problems before being given zoledronic acid injection.
- Inform patients of the importance of getting their blood tests (serum creatinine) during the course of their zoledronic acid injection therapy [see Warnings and Precautions (5.3)].
Osteonecrosis of the Jaw (ONJ)
- Advise patients to have a dental examination prior to treatment with zoledronic acid injection and to avoid invasive dental procedures during treatment.
- Inform patients of the importance of good dental hygiene, routine dental care, and regular dental check-ups.
- Advise patients to immediately tell their doctor about any oral symptoms such as loosening of a tooth, pain, swelling, or non-healing of sores or discharge during treatment with zoledronic acid injection [see Warnings and Precautions (5.4)].
Musculoskeletal Pain
Advise patients to immediately tell their doctor about any severe bone, joint, and/or muscle pain [see Warnings and Precautions (5.5)].
Atypical Subtrochanteric and Diaphyseal Femoral Fracture
Advise patients to report any thigh, hip, or groin pain. It is unknown whether the risk of atypical femur fracture continues after stopping therapy [see Warnings and Precautions (5.6)].
Patients With Asthma
There have been reports of bronchoconstriction in aspirin-sensitive patients receiving bisphosphonates, including zoledronic acid. Before being given zoledronic acid, instruct patients to tell their doctor if they are aspirin-sensitive [see Warnings and Precautions (5.7)].
Hypocalcemia
Advise patients with multiple myeloma and bone metastasis of solid tumors to take an oral calcium supplement of 500 mg and a multiple vitamin containing 400 international units of vitamin D daily [see Warnings and Precautions (5.9)].
Embryo-Fetal Toxicity
- Zoledronic acid injection should not be given if the patient is pregnant or plans to become pregnant. Inform female patients of the risk to a fetus and potential loss of the pregnancy [see Warnings and Precautions (5.10)].
- Advise females of reproductive potential to use effective contraception during and after treatment with zoledronic acid injection [see Warnings and Precautions (5.10), Use in Specific Populations (8.1, 8.3)].
Lactation
Advise lactating women not to breastfeed during and after treatment with zoledronic acid injection [see Use in Specific Populations (8.2)].
Common Adverse Reactions
Advise patients that the most common side effects of zoledronic acid injection are nausea, fatigue, anemia, bone pain, constipation, fever, vomiting, and dyspnea.
Reclast® is a registered trademark of Novartis Pharmaceuticals Corporation.
Manufactured for:
Westminster Pharmaceuticals, LLC
Nashville, TN 37217
Made in India
Revised: December 2022
3017177