PAMIDRONATE: 1,639 Adverse Event Reports & Safety Profile

DESCRIPTION Pamidronate disodium is a bisphosphonate available in 30 mg, 60 mg, or 90 mg vials for intravenous administration. The pamidronate disodium obtained by combining pamidronic acid and sodium hydroxide is provided in a sterile, ready to use solution for injection. Each mL of the 30 mg vial contains: 3 mg Pamidronate Disodium; 47 mg Mannitol, USP; Water for Injection, USP, q.s.; Phosphoric Acid and/or Sodium Hydroxide, as necessary to adjust pH. Each mL of the 60 mg vial contains: 6 mg Pamidronate Disodium; 40 mg Mannitol, USP; Water for Injection, USP, q.s.; Phosphoric Acid and/or Sodium Hydroxide, as necessary to adjust pH. Each mL of the 90 mg vial contains: 9 mg Pamidronate Disodium; 37.5 mg Mannitol, USP; Water for Injection, USP, q.s.; Phosphoric Acid and/or Sodium Hydroxide, as necessary to adjust pH. The pH of a 1% solution of pamidronate disodium in distilled water is approximately 8.3. Pamidronate, a member of the group of chemical compounds known as bisphosphonates, is an analog of pyrophosphate. Pamidronate disodium is designated chemically as phosphonic acid (3-amino-1-hydroxypropylidene) bis-, disodium salt, and its structural formula is: Pamidronate disodium is soluble in water and in 2N sodium hydroxide, sparingly soluble in 0.1N hydrochloric acid and in 0.1N acetic acid, and practically insoluble in organic solvents. Its molecular formula is C 3 H 9 NO 7 P 2 Na 2 and its molecular weight is 279.1 (calculated as the anhydrous form).

Inactive

Ingredients. Mannitol, USP, Phosphoric Acid and/or Sodium Hydroxide, as necessary (for adjustment to pH range of 6.0 - 7.0) and Water for Injection, USP. structural formula pamidronate disodium

INDICATIONS AND USAGE Hypercalcemia of Malignancy Pamidronate disodium, in conjunction with adequate hydration, is indicated for the treatment of moderate or severe hypercalcemia associated with malignancy, with or without bone metastases. Patients who have either epidermoid or non-epidermoid tumors respond to treatment with pamidronate disodium. Vigorous saline hydration, an integral part of hypercalcemia therapy, should be initiated promptly and an attempt should be made to restore the urine output to about 2 L/day throughout treatment. Mild or asymptomatic hypercalcemia may be treated with conservative measures (i.e., saline hydration, with or without loop diuretics). Patients should be hydrated adequately throughout the treatment, but overhydration, especially in those patients who have cardiac failure, must be avoided. Diuretic therapy should not be employed prior to correction of hypovolemia. The safety and efficacy of pamidronate disodium in the treatment of hypercalcemia associated with hyperparathyroidism or with other non-tumor-related conditions has not been established. Paget’s Disease Pamidronate disodium is indicated for the treatment of patients with moderate to severe Paget’s disease of bone. The effectiveness of pamidronate disodium was demonstrated primarily in patients with serum alkaline phosphatase ≥ 3 times the upper limit of normal. Pamidronate disodium therapy in patients with Paget’s disease has been effective in reducing serum alkaline phosphatase and urinary hydroxyproline levels by ≥ 50% in at least 50% of patients, and by ≥ 30% in at least 80% of patients. Pamidronate disodium therapy has also been effective in reducing these biochemical markers in patients with Paget’s disease who failed to respond, or no longer responded to other treatments.

Osteolytic Bone

Metastases of Breast Cancer and Osteolytic Lesions of Multiple Myeloma Pamidronate disodium is indicated, in conjunction with standard antineoplastic therapy, for the treatment of osteolytic bone metastases of breast cancer and osteolytic lesions of multiple myeloma. The pamidronate disodium treatment effect appeared to be smaller in the study of breast cancer patients receiving hormonal therapy than in the study of those receiving chemotherapy, however, overall evidence of clinical benefit has been demonstrated (see CLINICAL PHARMACOLOGY , Osteolytic Bone Metastases of Breast Cancer and Osteolytic Lesions of Multiple Myeloma, Clinical Trials section).

DOSAGE AND ADMINISTRATION Hypercalcemia of Malignancy Consideration should be given to the severity of as well as the symptoms of hypercalcemia. Vigorous saline hydration alone may be sufficient for treating mild, asymptomatic hypercalcemia. Overhydration should be avoided in patients who have potential for cardiac failure. In hypercalcemia associated with hematologic malignancies, the use of glucocorticoid therapy may be helpful.

Moderate Hypercalcemia

The recommended dose of pamidronate disodium in moderate hypercalcemia (corrected serum calcium* of approximately 12 to 13.5 mg/dL) is 60 to 90 mg given as a SINGLE DOSE, intravenous infusion over 2 to 24 hours. Longer infusions (i.e., >2 hours) may reduce the risk for renal toxicity, particularly in patients with preexisting renal insufficiency.

Severe Hypercalcemia

The recommended dose of pamidronate disodium in severe hypercalcemia (corrected serum calcium* >13.5 mg/dL) is 90 mg given as a SINGLE DOSE, intravenous infusion over 2 to 24 hours. Longer infusions (i.e., >2 hours) may reduce the risk for renal toxicity, particularly in patients with preexisting renal insufficiency. * Albumin-corrected serum calcium (CCa, mg/dL) = serum calcium, mg/dL + 0.8 (4.0-serum albumin, g/dL). Retreatment A limited number of patients have received more than one treatment with pamidronate disodium for hypercalcemia. Retreatment with pamidronate disodium, in patients who show complete or partial response initially, may be carried out if serum calcium does not return to normal or remain normal after initial treatment. It is recommended that a minimum of 7 days elapse before retreatment, to allow for full response to the initial dose . The dose and manner of retreatment is identical to that of the initial therapy. Paget’s Disease The recommended dose of pamidronate disodium in patients with moderate to severe Paget’s disease of bone is 30 mg daily, administered as a 4-hour infusion on 3 consecutive days for a total dose of 90 mg. Retreatment A limited number of patients with Paget’s disease have received more than one treatment of pamidronate disodium in clinical trials. When clinically indicated, patients should be retreated at the dose of initial therapy.

Osteolytic Bone

Lesions of Multiple Myeloma The recommended dose of pamidronate disodium in patients with osteolytic bone lesions of multiple myeloma is 90 mg administered as a 4-hour infusion given on a monthly basis. Patients with marked Bence-Jones proteinuria and dehydration should receive adequate hydration prior to pamidronate disodium infusion. Limited information is available on the use of pamidronate disodium in multiple myeloma patients with a serum creatinine ≥ 3.0 mg/dL. Patients who receive pamidronate disodium should have serum creatinine assessed prior to each treatment. Treatment should be withheld for renal deterioration. In a clinical study, renal deterioration was defined as follows: For patients with normal baseline creatinine, increase of 0.5 mg/dL. For patients with abnormal baseline creatinine, increase of 1.0 mg/dL. In this clinical study, pamidronate disodium treatment was resumed only when the creatinine returned to within 10% of the baseline value. The optimal duration of therapy is not yet known, however, in a study of patients with myeloma, final analysis after 21 months demonstrated overall benefits (see Clinical Trials section).

Osteolytic Bone

Metastases of Breast Cancer The recommended dose of pamidronate disodium in patients with osteolytic bone metastases is 90 mg administered over a 2-hour infusion given every 3 to 4 weeks. Pamidronate disodium has been frequently used with doxorubicin, fluorouracil, cyclophosphamide, methotrexate, mitoxantrone, vinblastine, dexamethasone, prednisone, melphalan, vincristine, megesterol, and tamoxifen. It has been given less frequently with etoposide, cisplatin, cytarabine, paclitaxel, and aminoglutethimide. Patients who receive pamidronate disodium should have serum creatinine assessed prior to each treatment. Treatment should be withheld for renal deterioration. In a clinical study, renal deterioration was defined as follows: For patients with normal baseline creatinine, increase of 0.5 mg/dL. For patients with abnormal baseline creatinine, increase of 1.0 mg/dL. In this clinical study, pamidronate disodium treatment was resumed only when the creatinine returned to within 10% of the baseline value. The optimal duration of therapy is not known, however, in two breast cancer studies, final analyses performed after 24 months of therapy demonstrated overall benefits (see Clinical Trials section). Calcium and Vitamin D Supplementation In the absence of hypercalcemia, patients with predominantly lytic bone metastases or multiple myeloma, who are at risk of calcium or vitamin D deficiency, and patients with Paget’s disease of the bone, should be given oral calcium and vitamin D supplementation in order to minimize the risk of hypocalcemia. Method of Administration DUE TO THE RISK OF CLINICALLY SIGNIFICANT DETERIORATION IN RENAL FUNCTION, WHICH MAY PROGRESS TO RENAL FAILURE, SINGLE DOSES OF PAMIDRONATE DISODIUM SHOULD NOT EXCEED 90 MG (SEE WARNINGS ). There must be strict adherence to the intravenous administration recommendations for pamidronate disodium in order to decrease the risk of deterioration in renal function. Hypercalcemia of Malignancy The daily dose must be administered as an intravenous infusion over at least 2 to 24 hours for the 60 mg and 90-mg doses. The recommended dose should be diluted in 1000 mL of sterile 0.45% or 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP. This infusion solution is stable for up to 24 hours at room temperature. Paget’s Disease The recommended daily dose of 30 mg should be diluted in 500 mL of sterile 0.45% or 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP, and administered over a 4-hour period for 3 consecutive days.

Osteolytic Bone

Metastases of Breast Cancer The recommended dose of 90 mg should be diluted in 250 mL of sterile 0.45% or 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP, and administered over a 2-hour period every 3 to 4 weeks.

Osteolytic Bone

Lesions of Multiple Myeloma The recommended dose of 90 mg should be diluted in 500 mL of sterile 0.45% or 0.9% Sodium Chloride, USP, or 5% Dextrose Injection, USP, and administered over a 4-hour period on a monthly basis. Pamidronate disodium must not be mixed with calcium-containing infusion solutions, such as Ringer’s solution, and should be given in a single intravenous solution and line separate from all other drugs. Note: Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

Pamidronate disodium is contraindicated in patients with hypersensitivity to pamidronate disodium, other bisphosphonates, or mannitol. Reactions to pamidronate disodium injection and to mannitol have included anaphylaxis. Hypersensitivity to pamidronate, other bisphosphonates, or mannitol ( 4 )

ADVERSE REACTIONS Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Clinical Studies

Hypercalcemia of Malignancy Transient mild elevation of temperature by at least 1°C was noted 24 to 48 hours after administration of pamidronate disodium in 34% of patients in clinical trials. In the saline trial, 18% of patients had a temperature elevation of at least 1°C 24 to 48 hours after treatment. Drug-related local soft-tissue symptoms (redness, swelling or induration and pain on palpation) at the site of catheter insertion were most common in patients treated with 90 mg of pamidronate disodium. Symptomatic treatment resulted in rapid resolution in all patients. Rare cases of uveitis, iritis, scleritis, and episcleritis have been reported, including one case of scleritis, and one case of uveitis upon separate rechallenges. Five of 231 patients (2%) who received pamidronate disodium during the four U.S. controlled hypercalcemia clinical studies were reported to have had seizures, 2 of whom had preexisting seizure disorders. None of the seizures were considered to be drug-related by the investigators. However, a possible relationship between the drug and the occurrence of seizures cannot be ruled out. It should be noted that in the saline arm 1 patient (4%) had a seizure. There are no controlled clinical trials comparing the efficacy and safety of 90 mg pamidronate disodium over 24 hours to 2 hours in patients with hypercalcemia of malignancy. However, a comparison of data from separate clinical trials suggests that the overall safety profile in patients who received 90 mg pamidronate disodium over 24 hours is similar to those who received 90 mg pamidronate disodium over 2 hours. The only notable differences observed were an increase in the proportion of patients in the pamidronate disodium 24-hour group who experienced fluid overload and electrolyte/mineral abnormalities. At least 15% of patients treated with pamidronate disodium for hypercalcemia of malignancy also experienced the following adverse events during a clinical trial: General: Fluid overload, generalized pain Cardiovascular: Hypertension Gastrointestinal: Abdominal pain, anorexia, constipation, nausea, vomiting Genitourinary: Urinary tract infection Musculoskeletal: Bone pain Laboratory Abnormality: Anemia, hypokalemia, hypomagnesemia, hypophosphatemia. Many of these adverse experiences may have been related to the underlying disease state. The following table lists the adverse experiences considered to be treatment-related during comparative, controlled U.S. trials. Treatment-Related Adverse Experiences Reported in Three U.S.

Controlled Clinical Trials

Percent of Patients Pamidronate Disodium Etidronate Disodium Saline 60 mg over 4 hr 60 mg over 24 hr 90 mg over 24 hr 7.5 mg/kg × 3 days n=23 n=73 n=17 n=35 n=23 General Edema 0 1 0 0 0 Fatigue 0 0 12 0 0 Fever 26 19 18 9 0 Fluid overload 0 0 0 6 0 Infusion-site reaction 0 4 18 0 0 Moniliasis 0 0 6 0 0 Rigors 0 0 0 0 4 Gastrointestinal Abdominal pain 0 1 0 0 0 Anorexia 4 1 12 0 0 Constipation 4 0 6 3 0 Diarrhea 0 1 0 0 0 Dyspepsia 4 0 0 0 0 Gastrointestinal hemorrhage 0 0 6 0 0 Nausea 4 0 18 6 0 Stomatitis 0 1 0 3 0 Vomiting 4 0 0 0 0 Respiratory Dyspnea 0 0 0 3 0 Rales 0 0 6 0 0 Rhinitis 0 0 6 0 0 Upper respiratory infection 0 3 0 0 0 CNS Anxiety 0 0 0 0 4 Convulsions 0 0 0 3 0 Insomnia 0 1 0 0 0 Nervousness 0 0 0 0 4 Psychosis 4 0 0 0 0 Somnolence 0 1 6 0 0 Taste perversion 0 0 0 3 0 Cardiovascular Atrial fibrillation 0 0 6 0 4 Atrial flutter 0 1 0 0 0 Cardiac failure 0 1 0 0 0 Hypertension 0 0 6 0 4 Syncope 0 0 6 0 0 Tachycardia 0 0 6 0 4 Endocrine Hypothyroidism 0 0 6 0 0 Hemic and Lymphatic Anemia 0 0 6 0 0 Leukopenia 4 0 0 0 0 Neutropenia 0 1 0 0 0 Thrombocytopenia 0 1 0 0 0 Musculoskeletal Myalgia 0 1 0 0 0 Urogenital Uremia 4 0 0 0 0 Laboratory Abnormalities Hypocalcemia 0 1 12 0 0 Hypokalemia 4 4 18 0 0 Hypomagnesemia 4 10 12 3 4 Hypophosphatemia 0 9 18 3 0 Abnormal liver function 0 0 0 3 0 Paget’s Disease Transient mild elevation of temperature >1°C above pretreatment baseline was noted within 48 hours after completion of treatment in 21% of the patients treated with 90 mg of pamidronate disodium in clinical trials. Drug-related musculoskeletal pain and nervous system symptoms (dizziness, headache, paresthesia, increased sweating) were more common in patients with Paget’s disease treated with 90 mg of pamidronate disodium than in patients with hypercalcemia of malignancy treated with the same dose. Adverse experiences considered to be related to trial drug, which occurred in at least 5% of patients with Paget’s disease treated with 90 mg of pamidronate disodium in two U.S. clinical trials, were fever, nausea, back pain, and bone pain. At least 10% of all pamidronate disodium-treated patients with Paget’s disease also experienced the following adverse experiences during clinical trials: Cardiovascular: Hypertension Musculoskeletal: Arthrosis, bone pain Nervous system: Headache Most of these adverse experiences may have been related to the underlying disease state.

Osteolytic Bone

Metastases of Breast Cancer and Osteolytic Lesions of Multiple Myeloma The most commonly reported (>15%) adverse experiences occurred with similar frequencies in the pamidronate disodium and placebo treatment groups, and most of these adverse experiences may have been related to the underlying disease state or cancer therapy.

Commonly Reported Adverse

Experiences in Three U.S.

Controlled Clinical Trials Pamidronate Disodium

90 mg over 4 hours Placebo Pamidronate Disodium 90 mg over 2 hours Placebo All Pamidronate Disodium 90 mg Placebo N=205 N=187 N=367 N=386 N=572 N=573 General % % % % % % Asthenia 16.1 17.1 25.6 19.2 22.2

18.5 Fatigue 31.7 28.3 40.3 28.8 37.2

29.0 Fever 38.5 38 38.1 32.1 38.5 34 Metastases 1.0 3.0 31.3 24.4 20.5

17.5 Pain 13.2 11.8 15.0 18.1 14.3

16.1 Digestive System Anorexia 17.1 17.1 31.1 24.9 26.0

22.3 Constipation 28.3 31.7 36.0 38.6 33.2

35.1 Diarrhea 26.8 26.8 29.4 30.6 28.5

29.7 Dyspepsia 17.6 13.4 18.3 15.0 22.6

17.5 Nausea 35.6 37.4 63.5 59.1 53.5

51.8 Pain abdominal 19.5 16.0 24.3 18.1 22.6

17.5 Vomiting 16.6 19.8 46.3 39.1 35.7

32.8 Hemic and Lymphatic Anemia 47.8 41.7 39.5 36.8 42.5

38.4 Granulocytopenia 20.5 15.5 19.3 20.5 19.8

18.8 Thrombocytopenia 16.6 17.1 12.5 14.0 14.0

15.0 Musculoskeletal System Arthralgias 10.7 7.0 15.3 12.7 13.6

10.8 Myalgia 25.4 15.0 26.4 22.5 26

20.1 Skeletal Pain 61.0 71.7 70.0 75.4 66.8 74 CNS Anxiety 7.8 9.1 18.0 16.8 14.3

14.3 Headache 24.4 19.8 27.2 23.6 26.2

22.3 Insomnia 17.1 17.2 25.1 19.4 22.2

19.0 Respiratory System Coughing 26.3 22.5 25.3 19.7 25.7

20.6 Dyspnea 22.0 21.4 35.1 24.4 30.4

23.4 Pleural effusion 2.9 4.3 15.0 9.1 10.7

7.5 Sinusitis 14.6 16.6 16.1 10.4 15.6

12.0 Upper respiratory Tract Infection 32.2 28.3 19.6 20.2 24.1

22.9 Urogenital System Urinary Tract Infection 15.6 9.1 20.2 17.6 18.5

15.6 Of the toxicities commonly associated with chemotherapy, the frequency of vomiting, anorexia, and anemia were slightly more common in the pamidronate disodium patients whereas stomatitis and alopecia occurred at a frequency similar to that in placebo patients. In the breast cancer trials, mild elevations of serum creatinine occurred in 18.5% of pamidronate disodium patients and 12.3% of placebo patients. Mineral and electrolyte disturbances, including hypocalcemia, were reported rarely and in similar percentages of pamidronate disodium-treated patients compared with those in the placebo group. The reported frequencies of hypocalcemia, hypokalemia, hypophosphatemia, and hypomagnesemia for pamidronate disodium-treated patients were 3.3%, 10.5%, 1.7%, and 4.4%, respectively, and for placebo-treated patients were 1.2%, 12%, 1.7%, and 4.5%, respectively. In previous hypercalcemia of malignancy trials, patients treated with pamidronate disodium (60 or 90 mg over 24 hours) developed electrolyte abnormalities more frequently (see ADVERSE REACTIONS , Hypercalcemia of Malignancy ). Arthralgias and myalgias were reported slightly more frequently in the pamidronate disodium group than in the placebo group (13.6% and 26% vs 10.8% and 20.1%, respectively). In multiple myeloma patients, there were five pamidronate disodium-related serious and unexpected adverse experiences. Four of these were reported during the 12-month extension of the multiple myeloma trial. Three of the reports were of worsening renal function developing in patients with progressive multiple myeloma or multiple myeloma-associated amyloidosis. The fourth report was the adult respiratory distress syndrome developing in a patient recovering from pneumonia and acute gangrenous cholecystitis. One pamidronate disodium-treated patient experienced an allergic reaction characterized by swollen and itchy eyes, runny nose, and scratchy throat within 24 hours after the sixth infusion. In the breast cancer trials, there were four pamidronate disodium-related adverse experiences, all moderate in severity, that caused a patient to discontinue participation in the trial. One was due to interstitial pneumonitis, another to malaise and dyspnea. One pamidronate disodium patient discontinued the trial due to a symptomatic hypocalcemia. Another pamidronate disodium patient discontinued therapy due to severe bone pain after each infusion, which the investigator felt was trial-drug-related.

Renal

Toxicity In a study of the safety and efficacy of pamidronate disodium 90 mg (2 hour infusion) versus Zometa ® 4 mg (15 minute infusion) in bone metastases patients with multiple myeloma or breast cancer, renal deterioration was defined as an increase in serum creatinine of 0.5 mg/dL for patients with normal baseline creatinine (<1.4 mg/dL) or an increase of 1.0 mg/dL for patients with an abnormal baseline creatinine (≥ 1.4 mg/dL). The following are data on the incidence of renal deterioration in patients in this trial. See table below. Incidence of Renal Function Deterioration in Multiple Myeloma and Breast Cancer Patients with Normal and Abnormal Serum Creatinine at Baseline Patients were randomized following the 15-minute infusion amendment for the Zometa ® arm. Zometa ® is a registered trademark of Novartis.

Patient Population/Baseline

Creatinine Pamidronate Disodium 90 mg/2 hours Zometa ® 4 mg/15 minutes n/N (%) n/N (%)

Normal

20/246 (8.1%) 23/246 (9.3%)

Abnormal

2/22 (9.1%) 1/26 (3.8%)

Total

22/268 (8.2%) 24/272 (8.8%) Post-Marketing Experience The following adverse reactions have been reported during post-approval use of pamidronate disodium. Because these reports are from a population of uncertain size and are subject to confounding factors, it is not possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The following adverse reactions have been reported in post-marketing use: General: reactivation of Herpes simplex and Herpes zoster, influenza-like symptoms; CNS: confusion and visual hallucinations, sometimes in the presence of electrolyte imbalance; Skin: rash, pruritus; Special senses: conjunctivitis, orbital inflammation; Renal and urinary disorders: focal segmental glomerulosclerosis including the collapsing variant, nephrotic syndrome; renal tubular disorders (RTD); tubulointerstitial nephritis, and glomerulonephropathies. Laboratory abnormalities: hyperkalemia, hypernatremia, hematuria. Rare instances of allergic manifestations have been reported, including hypotension, dyspnea, or angioedema, and, very rarely, anaphylactic shock. Pamidronate disodium is contraindicated in patients with clinically significant hypersensitivity to pamidronate disodium or other bisphosphonates (see CONTRAINDICATIONS . ) Respiratory, thoracic and mediastinal disorders: adult respiratory distress syndrome (ARDS), interstitial lung disease (ILD). Musculoskeletal and connective tissue disorders: severe and occasionally incapacitating bone, joint, and/or muscle pain. Cases of osteonecrosis (primarily involving the jaw) have been reported predominantly in cancer patients treated with intravenous bisphosphonates, including pamidronate disodium. Many of these patients were also receiving chemotherapy and corticosteroids which may be risk factors for ONJ. Data suggest 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 PRECAUTIONS ). Atypical subtrochanteric and diaphyseal femoral fractures have been reported with bisphosphonate therapy, including pamidronate disodium (See PRECAUTIONS ).

AND PRECAUTIONS

• Renal failure: Do not exceed single doses of 90 mg pamidronate disodium. Assess renal function before each treatment. In patients with bone metastases with severe renal impairment, use of pamidronate disodium is not recommended. ( 5.1 )
• Embryo-Fetal Toxicity: Can cause fetal harm. Advise females of reproductive potential of the potential risk to a fetus and to use effective contraception. ( 5.2 , 8.1 , 8.3 )
• Electrolyte disorders (e.g., hypophosphatemia, hypokalemia, hypomagnesemia, hypocalcemia): Monitor phosphorus, potassium, magnesium, calcium and vitamin D and adequately supplement as appropriate. ( 5.3 )
• Osteonecrosis of the jaw: Perform preventive dental procedures prior to initiating pamidronate disodium. Avoid invasive procedures if possible in patients receiving pamidronate disodium. ( 5.4 )
• Atypical fractures of the femur can occur after minimal or no trauma. Evaluate patients with thigh or groin pain for possible fracture. ( 5.5 )

5.1 Deterioration in Renal Function, Use in Patients with Renal Impairment Bisphosphonates, such as pamidronate disodium, have been associated with renal toxicity, including focal segmental glomerulosclerosis. This toxicity has been manifested as nephritic syndrome, deterioration of renal function, and renal failure. Renal failure has been reported in patients after a single dose of pamidronate disodium. Some patients had gradual improvement in renal status after pamidronate disodium was discontinued. Do not administer single doses of pamidronate disodium in excess of 90 mg due to the risk of clinically significant deterioration in renal function, <span class="opacity-50 text-xs">[see Dosage and Administration (2.5) ]</span> . Assess serum creatinine prior to each treatment. Withhold treatment until renal function returns to baseline in patients who show evidence of deterioration in renal function. Do not administer pamidronate in patients with severe renal impairment for the treatment of bone metastases <span class="opacity-50 text-xs">[see Dosage and Administration (2.1 , 2.2 , 2.3) ]</span> .

5.2 Embryo-Fetal Toxicity Based on findings in animals and its mechanism of action, pamidronate disodium can cause fetal harm when administered to a pregnant woman <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.1) ]</span> . In reproductive studies, administration of pamidronate to pregnant rats and rabbits at doses equivalent to 0.6 to 8.3 times the highest human recommended dose resulted in maternal toxicity and embryo-fetal effects. Bisphosphonates, such as pamidronate disodium, 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. Advise females of reproductive potential to use effective contraception during and after pamidronate disodium treatment <span class="opacity-50 text-xs">[see Use in Specific Populations (8.1 , 8.3) ]</span> .

5.3 Electrolyte Disorders Cases of asymptomatic hypophosphatemia (12%), hypokalemia (7%), hypomagnesemia (11%), and hypocalcemia (5% to 17%), were reported in pamidronate disodium-treated patients. Cases of symptomatic hypocalcemia (including tetany) have been reported in association with pamidronate disodium therapy. Monitor serum levels of calcium, phosphate, magnesium, and potassium, following initiation of therapy with pamidronate disodium. If hypocalcemia occurs, short-term calcium therapy may be necessary. In the absence of hypercalcemia, supplement with oral calcium and vitamin D in order to minimize the risk of hypocalcemia.

5.4 Osteonecrosis of the Jaw Osteonecrosis of the jaw (ONJ) has been reported predominantly in cancer patients treated with intravenous bisphosphonates, including pamidronate disodium. Many of these patients were also receiving chemotherapy and corticosteroids, which may be risk factors for ONJ. Postmarketing experience and the literature suggest a greater frequency of ONJ with certain tumor type (advanced breast cancer, multiple myeloma), and dental status (dental extraction, periodontal disease, local trauma including poorly fitting dentures). Local infection including osteomyelitis has been reported with ONJ. Patients receiving pamidronate should maintain good oral hygiene and have a dental examination with preventive dentistry prior to initiation of treatment. While on treatment, avoid invasive dental procedures if possible. For patients who develop ONJ while on bisphosphonate therapy, dental surgery may exacerbate the condition. For patients requiring dental procedures, there are no data available to suggest whether discontinuation of bisphosphonate treatment reduces the risk of ONJ. Clinical judgment of the treating physician should guide the management plan of each patient based on individual benefit/risk assessment <span class="opacity-50 text-xs">[see Adverse Reactions (6.2) ]</span> .

5.5 Atypical Fractures of the Femur Atypical subtrochanteric and diaphyseal femoral fractures have been reported in patients receiving bisphosphonate therapy, including pamidronate disodium. These fractures can occur anywhere in the femoral shaft from just below the lesser trochanter to just above the supracondylar flare and are transverse or short oblique in orientation without evidence of comminution. These fractures may occur after minimal or no trauma. Patients may experience thigh or groin pain weeks to months before presenting with a completed femoral fracture. Fractures are often bilateral; therefore, the contralateral femur should be examined in bisphosphonate-treated patients who have sustained a femoral shaft fracture. Poor healing of these fractures also has been reported. A number of case reports noted that patients were receiving treatment also with glucocorticoids (such as prednisone or dexamethasone) at the time of fracture. Causality with bisphosphonate therapy has not been established. Any patient with a history of bisphosphonate exposure who presents with thigh or groin pain in the absence of trauma should be evaluated for an atypical fracture. Consider discontinuation of pamidronate disodium therapy in patients suspected to have an atypical femur fracture pending evaluation of the patient, based on an individual benefit risk assessment. It is unknown whether the risk of atypical femur fracture continues after stopping therapy.

PRECAUTIONS General Standard hypercalcemia-related metabolic parameters, such as serum levels of calcium, phosphate, magnesium, and potassium, should be carefully monitored following initiation of therapy with pamidronate disodium. Cases of asymptomatic hypophosphatemia (12%), hypokalemia (7%), hypomagnesemia (11%), and hypocalcemia (5% to 12%), were reported in pamidronate disodium-treated patients. Rare cases of symptomatic hypocalcemia (including tetany) have been reported in association with pamidronate therapy. If hypocalcemia occurs, short-term calcium therapy may be necessary.

In

Paget’s disease of bone, 17% of patients treated with 90 mg of pamidronate disodium showed serum calcium levels below 8 mg/dL. Patients with a history of thyroid surgery may have relative hypoparathyroidism that may predispose to hypocalcemia with pamidronate disodium.

Renal Insufficiency

Pamidronate disodium is excreted intact primarily via the kidney, and the risk of renal adverse reactions may be greater in patients with impaired renal function. Patients who receive pamidronate disodium should have serum creatinine assessed prior to each treatment. In patients receiving pamidronate disodium for bone metastases, who show evidence of deterioration in renal function, pamidronate disodium treatment should be withheld until renal function returns to baseline (see WARNINGS and DOSAGE AND ADMINISTRATION ). In clinical trials, patients with renal impairment (serum creatinine >3.0 mg/dL) have not been studied. Limited pharmacokinetic data exist in patients with creatinine clearance <30 mL/min (See Clinical Pharmacology , Pharmacokinetics ). For the treatment of bone metastases, the use of pamidronate disodium in patients with severe renal impairment is not recommended. In other indications, clinical judgment should determine whether the potential benefit outweighs the potential risk in such patients. Osteonecrosis of the Jaw Osteonecrosis of the jaw (ONJ) has been reported predominantly in cancer patients treated with intravenous bisphosphonates, including pamidronate disodium. Many of these patients were also receiving chemotherapy and corticosteroids which may be risk factors for ONJ. Post-marketing experience and the literature suggest a greater frequency of reports of ONJ based on tumor type (advanced breast cancer, multiple myeloma), and dental status (dental extraction, periodontal disease, local trauma including poorly fitting dentures). Many reports of ONJ involved patients with signs of local infection including osteomyelitis. Cancer patients should maintain good oral hygiene and should have a dental examination with preventive dentistry prior to treatment with bisphosphonates. While on treatment, these patients should avoid invasive dental procedures if possible. For patients who develop ONJ while on bisphosphonate therapy, dental surgery may exacerbate the condition. For patients requiring dental procedures, there are no data available to suggest whether discontinuation of bisphosphonate treatment reduces the risk of ONJ. Clinical judgment of the treating physician should guide the management plan of each patient based on individual benefit/risk assessment (see ADVERSE REACTIONS ).

Musculoskeletal

Pain In post-marketing experience, severe and occasionally incapacitating bone, joint, and/or muscle pain has been reported in patients taking bisphosphonates. This category of drugs includes pamidronate disodium. The time to onset of symptoms varied from one day to several months after starting the drug. Most patients had relief of symptoms after stopping. A subset had recurrence of symptoms when rechallenged with the same drug or another bisphosphonate. Atypical fractures of the femur Atypical subtrochanteric and diaphyseal femoral fractures have been reported in patients receiving bisphosphonate therapy, including pamidronate disodium. These fractures can occur anywhere in the femoral shaft from just below the lesser trochanter to just above the supracondylar flare and are transverse or short oblique in orientation without evidence of comminution. These fractures occur after minimal or no trauma. Patients may experience thigh or groin pain weeks to months before presenting with a completed femoral fracture. Fractures are often bilateral; therefore the contralateral femur should be examined in bisphosphonate-treated patients who have sustained a femoral shaft fracture. Poor healing of these fractures has also been reported. A number of case reports noted that patients were also receiving treatment with glucocorticoids (such as prednisone or dexamethasone) at the time of fracture. Causality with bisphosphonate therapy has not been established. Any patient with a history of bisphosphonate exposure who presents with thigh or groin pain in the absence of trauma should be suspected of having an atypical fracture and should be evaluated. Discontinuation of pamidronate disodium therapy in patients suspected to have an atypical femur fracture should be considered pending evaluation of the patient, based on an individual benefit risk assessment. It is unknown whether the risk of atypical femur fracture continues after stopping therapy.

Laboratory Tests

Patients who receive pamidronate disodium should have serum creatinine assessed prior to each treatment. Serum calcium, electrolytes, phosphate, magnesium, and CBC, differential, and hematocrit/hemoglobin must be closely monitored in patients treated with pamidronate disodium. Patients who have preexisting anemia, leukopenia, or thrombocytopenia should be monitored carefully in the first 2 weeks following treatment. Patients receiving pamidronate disodium may be at risk for anemia, leukopenia or thrombocytopenia and should have regular hematology assessments.

Drug Interactions

Concomitant administration of a loop diuretic had no effect on the calcium-lowering action of pamidronate disodium. Caution is indicated when pamidronate disodium is used with other potentially nephrotoxic drugs. In multiple myeloma patients, the risk of renal function deterioration may be increased when pamidronate disodium is used in combination with thalidomide. Carcinogenesis, Mutagenesis, Impairment of Fertility In a 104-week carcinogenicity study with daily oral administration of pamidronate in rats, there was a positive dose response relationship for benign adrenal pheochromocytoma in males (P <0.00001). Although this condition was also observed in females, the incidence was not statistically significant. When the dose calculations were adjusted to account for the limited oral bioavailability of pamidronate in rats, systemic exposure with the lowest daily dose associated with adrenal pheochromocytoma resulted in systemic exposures that were similar to the systemic exposure achieved at the intended clinical dose. Adrenal pheochromocytoma was also observed in low numbers in the control animals and is considered a relatively common spontaneous neoplasm in the rat. Pamidronate given daily by oral administration was not carcinogenic in an 80-week study in mice. Pamidronate was nonmutagenic in six mutagenicity assays, including: Ames bacterial mutagenicity assay, (with and without metabolic activation), nucleus-anomaly test, sister-chromatid-exchange study, point-mutation test, and micronucleus test in the rat. In rats, decreased fertility occurred in first-generation offspring of parents who had received 150 mg/kg of pamidronate orally; however, this occurred only when animals were mated with members of the same dose group. Pamidronate has not been administered intravenously in such a study.

Animal

Toxicology In both rats and dogs, nephropathy has been associated with intravenous (bolus and infusion) administration of pamidronate.

Two

7-day intravenous infusion studies were conducted in the dog wherein pamidronate was given for 1, 4, or 24 hours at doses of 1 to 20 mg/kg for up to 7 days. In the first study, the compound was well tolerated at 3 mg/kg (1.7 x highest recommended human dose [HRHD] for a single intravenous infusion) when administered for 4 or 24 hours, but renal findings such as elevated BUN and creatinine levels and renal tubular necrosis occurred when 3 mg/kg was infused for 1 hour and at doses of ≥10 mg/kg. In the second study, slight renal tubular necrosis was observed in 1 male at 1 mg/kg when infused for 4 hours. Additional findings included elevated BUN levels in several treated animals and renal tubular dilation and/or inflammation at ≥1 mg/kg after each infusion time. Pamidronate was given to rats at doses of 2, 6, and 20 mg/kg and to dogs at doses of 2, 4, 6, and 20 mg/kg as a 1-hour infusion, once a week, for 3 months followed by a 1-month recovery period. In rats, nephrotoxicity was observed at ≥6 mg/kg and included increased BUN and creatinine levels and tubular degeneration and necrosis. These findings were still present at 20 mg/kg at the end of the recovery period. In dogs, moribundity/death and renal toxicity occurred at 20 mg/kg as did kidney findings of elevated BUN and creatinine levels at ≥6 mg/kg and renal tubular degeneration at ≥4 mg/kg. The kidney changes were partially reversible at 6 mg/kg. In both studies, the dose level that produced no adverse renal effects was considered to be 2 mg/kg (1.1 x HRHD for a single intravenous infusion). Pregnancy (See WARNINGS ) There are no adequate and well-controlled studies in pregnant women. Pamidronate disodium may cause fetal harm when administered to a pregnant woman. Bisphosphonates, such as pamidronate disodium, are incorporated into the bone matrix, from where they are gradually released over periods of weeks to years. The extent of bisphosphonate incorporation into adult bone, and hence, the amount available for release back into the systemic circulation, is directly related to the total dose and duration of bisphosphonate use. Although there are no data on fetal risk in humans, bisphosphonates do cause fetal harm in animals, and animal data suggest that uptake of bisphosphonates into fetal bone is greater than into maternal bone. Therefore, there is a theoretical risk of fetal harm (e.g. skeletal and other abnormalities) if a woman becomes pregnant after completing a course of bisphosphonate therapy. The impact of variables such as time between cessation of bisphosphonate therapy to conception, the particular bisphosphonate used, and the route of administration (intravenous versus oral) on this risk has not been established. If pamidronate disodium is used during pregnancy or if the patient becomes pregnant while taking or after taking this drug, the patient should be apprised of the potential hazard to the fetus. Intravenous bolus dosing of pregnant rats and rabbits with pamidronate resulted in maternal toxicity and embryo/fetal effects when given during organogenesis at doses of 0.6 to 8.3 times the highest recommended human dose for a single intravenous infusion. Pamidronate can cross the placenta in rats and has produced marked maternal and nonteratogenic embryo/fetal effects in both rats and rabbits.

Nursing

Mothers It is not known whether pamidronate is excreted in human milk. Because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants from pamidronate disodium, a decision should be made to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

Safety and effectiveness of pamidronate disodium in pediatric patients have not been established.

Geriatric

Use Of the total number of subjects in clinical studies of pamidronate disodium, approximately 20% were 65 and over, while approximately 15% were 75 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older individuals cannot be ruled out. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

INTERACTIONS

• Nephrotoxic drugs: Use with caution. ( 7.1 )
• Thalidomide: Increased risk of renal dysfunction in patients with multiple myeloma. ( 7.2 )

7.1 Nephrotoxic Drugs Caution is indicated when pamidronate disodium is used with other potentially nephrotoxic drugs.

7.2 Thalidomide In multiple myeloma patients, the risk of renal deterioration may be increased when pamidronate disodium is used in combination with thalidomide.

7.3 Loop Diuretics Concomitant administration of a loop diuretic had no effect on the calcium-lowering action of pamidronate disodium.