Ambisome Drug Information

AmBisome is not interchangeable or substitutable on a mg per mg basis with other amphotericin B products. Different amphotericin B products are not equivalent in terms of pharmacodynamics, pharmacokinetics and dosing. Am B isome should be administered by intravenous infusion, using a controlled infusion device, over a period of approximately 120 minutes.

An in-line membrane filter may be used for the intravenous infusion of Am B isome, provided THE MEAN PORE DIAMETER OF THE FILTER IS NOT LESS THAN 1.0 MICRON. NOTE: An existing intravenous line must be flushed with 5% Dextrose Injection prior to infusion of AmBisome. If this is not feasible, AmBisome must be administered through a separate line.

Infusion time may be reduced to approximately 60 minutes in patients in whom the treatment is well-tolerated. If the patient experiences discomfort during infusion, the duration of infusion may be increased. The recommended initial dose of Am B isome for each indication for adult and pediatric patients is as follows: 6 Dosing and rate of infusion should be individualized to the needs of the specific patient to ensure maximum efficacy while minimizing systemic toxicities or adverse events.

Doses recommended for visceral leishmaniasis are presented below: For immunocompetent patients who do not achieve parasitic clearance with the recommended dose, a repeat course of therapy may be useful. For immunocompromised patients who do not clear parasites or who experience relapses, expert advice regarding further treatment is recommended. For additional information, see DESCRIPTION OF CLINICAL STUDIES.

Directions for Reconstitution, Filtration and Dilution Read This Entire Section Carefully Before Beginning Reconstitution Am B isome must be reconstituted using Sterile Water for Injection, USP (without a bacteriostatic agent). Vials of Am B isome containing 50 mg of amphotericin B are prepared as follows: Reconstitution 1. Aseptically add 12 mL of Sterile Water for Injection, USP to each Am B isome vial to yield a preparation containing 4 mg amphotericin B/mL.

CAUTION: DO NOT RECONSTITUTE WITH SALINE OR ADD SALINE TO THE RECONSTITUTED CONCENTRATION, OR MIX WITH OTHER DRUGS. The use of any solution other than those recommended, or the presence of a bacteriostatic agent in the solution, may cause precipitation of Am B isome. 2. Immediately after the addition of water, SHAKE THE VIAL VIGOROUSLY for 30 seconds to completely disperse the Am B isome.

Am B isome forms a yellow, translucent suspension. Visually inspect the vial for particulate matter and continue shaking until completely dispersed. Filtration and Dilution 3.

Calculate the amount of reconstituted (4 mg/mL) Am B isome to be further diluted. 4. Withdraw this amount of reconstituted Am B isome into a sterile syringe. 5. Attach the 5 micron filter provided to the syringe.

Inject the syringe contents through the filter, into the appropriate amount of 5% Dextrose Injection (use only one filter per vial of Am B isome). 6. Am B isome must be diluted with 5% Dextrose Injection to a final concentration of 1 to 2 mg/mL prior to administration. Lower concentrations (0.2 to 0.5 mg/mL) may be appropriate for infants and small children to provide sufficient volume for infusion.

DISCARD PARTIALLY USED VIALS.

Am B isome and amphotericin B were infused over two hours. The incidence of common adverse events (incidence of 10% or greater) occurring with Am B isome compared to amphotericin B deoxycholate, regardless of relationship to study drug, is shown in the following table: Empirical Therapy Study Am B isome was well tolerated. Am B isome had a lower incidence of chills, hypertension, hypotension, tachycardia, hypoxia, hypokalemia, and various events related to decreased kidney function as compared to amphotericin B deoxycholate.

Similar trends, although with a somewhat lower incidence, were observed in open-label, randomized Study 104-14 involving 205 febrile neutropenic pediatric patients (141 treated with Am B isome and 64 treated with amphotericin B deoxycholate). Pediatric patients appear to have more tolerance than older individuals for the nephrotoxic effects of amphotericin B deoxycholate. The incidence of adverse events occurring in more than 10% of subjects in one or more arms, regardless of relationship to study drug, are summarized in the following table: Empirical Therapy Study 97-0-034 Common Adverse The following adverse events are based on the experience of 267 patients (266 adult patients and 1 pediatric patient) of whom 86 patients were treated with Am B isome 3 mg/kg, 94 patients were treated with Am B isome 6 mg/kg and 87 patients were treated with amphotericin B deoxycholate 0.7 mg/kg in Study 94-0-013 a randomized, double-blind, comparative multi-center trial, in the treatment of cryptococcal meningitis in HIV-positive patients.

The incidence of adverse events occurring in more than 10% of subjects in one or more arms regardless of relationship to study drug are summarized in the following table: Cryptococcal Meningitis Therapy Study -0-002, the large, double-blind study of pediatric and adult febrile neutropenic patients, no premedication to prevent infusion-related reaction was administered prior to the first dose of study drug (Day 1). The incidence of infusion-related reactions on Day 1 in pediatric and adult patients is summarized in the following table: Incidence of Day 1 Infusion-Related Reactions (IRR) By Patient Age Day 1 body temperature increased above the temperature taken within 1 hour prior to infusion (preinfusion temperature) or above the lowest infusion value (no preinfusion temperature recorded). Cardiorespiratory events, except for vasodilatation (flushing), during all study drug infusions were more frequent in amphotericin B-treated patients as summarized in the following table: The percentage of patients who received drugs either for the treatment or prevention of infusion-related reactions (e.g., acetaminophen, diphenhydramine, meperidine and hydrocortisone) was lower in Am B isome-treated patients compared with amphotericin B deoxycholate-treated patients.

In the empirical therapy study 97-0-034, on Day 1, where no premedication was administered, the overall incidence of infusion-related events of chills/rigors was significantly lower for patients administered Am B isome compared with amphotericin B lipid complex. Fever, chills/rigors and hypoxia were significantly lower for each Am B isome group compared with the amphotericin B lipid complex group. Incidence of Day 1 Infusion-Related Reactions (IRR) Chills/Rigors Empirical Therapy Study 97-0-034 Day 1 body temperature increased above the temperature taken within 1 hour prior to infusion (preinfusion temperature) or above the lowest infusion value (no preinfusion temperature recorded).

Patients were not administered premedications to prevent infusion-related reactions prior to the Day 1 study drug infusion. In Study 94-0-013, a randomized, double-blind, multicenter trial comparing Am B isome and amphotericin B deoxycholate as initial therapy for cryptococcal meningitis, premedications to prevent infusion-related reactions were permitted. Am B isome-treated patients had a lower incidence of fever, chills/rigors and respiratory adverse events as summarized in the following table: There have been a few reports of flushing, back pain with or without chest tightness, and chest pain associated with Am B isome administration; on occasion this has been severe.

Where these symptoms were noted, the reaction developed within a few minutes after the start of infusion and disappeared rapidly when the infusion was stopped. The symptoms do not occur with every dose and usually do not recur on subsequent administrations when the infusion rate is slowed. Toxicity and Discontinuation of Dosing In Study 94-0-002, a significantly lower incidence of grade 3 or 4 toxicity was observed in the Am B isome group compared with the amphotericin B group.

In addition, nearly three times as many patients administered amphotericin B required a reduction in dose due to toxicity or discontinuation of study drug due to an infusion-related reaction compared with those administered Am B isome. In empirical therapy study 97-0-034, a greater proportion of patients in the amphotericin B lipid complex group discontinued the study drug due to an adverse event than in the Am B isome groups. Less Common Adverse Events The following adverse events also have been reported in 2% to 10% of Am B isome-treated patients receiving chemotherapy or bone marrow transplantation, or who had HIV disease in six comparative, clinical trials: Body as a Whole Abdomen enlarged, allergic reaction, cellulitis, cell-mediated immunological reaction, face edema, graft-versus-host disease, malaise, neck pain, and procedural complication.

Cardiovascular System Arrhythmia, atrial fibrillation, bradycardia, cardiac arrest, cardiomegaly, hemorrhage, postural hypotension, valvular heart disease, vascular disorder, and vasodilatation (flushing). Digestive System Anorexia, constipation, dry mouth/nose, dyspepsia, dysphagia, eructation, fecal incontinence, flatulence, hemorrhoids, gum/oral hemorrhage, hematemesis, hepatocellular damage, hepatomegaly, liver function test abnormal, ileus, mucositis, rectal disorder, stomatitis, ulcerative stomatitis, and veno-occlusive liver disease. Hemic & Lymphatic System Anemia, coagulation disorder, ecchymosis, fluid overload, petechia, prothrombin decreased, prothrombin increased, and thrombocytopenia.

Metabolic & Nutritional Disorders Acidosis, amylase increased, hyperchloremia, hyperkalemia, hypermagnesemia, hyperphosphatemia, hyponatremia, hypophosphatemia, hypoproteinemia, lactate dehydrogenase increased, nonprotein nitrogen (NPN) increased, and respiratory alkalosis. Musculoskeletal System Arthralgia, bone pain, dystonia, myalgia, and rigors. Nervous System Agitation, coma, convulsion, cough, depression, dysesthesia, dizziness, hallucinations, nervousness, paresthesia, somnolence, thinking abnormality, and tremor.

Respiratory System Asthma, atelectasis, hemoptysis, hiccup, hyperventilation, influenza-like symptoms, lung edema, pharyngitis, pneumonia, respiratory insufficiency, respiratory failure, and sinusitis. Skin & Appendages Alopecia, dry skin, herpes simplex, injection site inflammation, maculopapular rash, purpura, skin discoloration, skin disorder, skin ulcer, urticaria, and vesiculobullous rash. Special Senses Conjunctivitis, dry eyes, and eye hemorrhage.

Urogenital System Abnormal renal function, acute kidney failure, acute renal failure, dysuria, kidney failure, toxic nephropathy, urinary incontinence, and vaginal hemorrhage. Post-marketing Experience The following infrequent adverse experiences have been reported in post-marketing surveillance, in addition to those mentioned above: angioedema, erythema, urticaria, bronchospasm, cyanosis/hypoventilation, pulmonary edema, agranulocytosis, hemorrhagic cystitis, and rhabdomyolysis. Clinical Laboratory Values The effect of Am B isome on renal and hepatic function and on serum electrolytes was assessed from laboratory values measured repeatedly in Study 94-0-002.

The frequency and magnitude of hepatic test abnormalities were similar in the Am B isome and amphotericin B groups. Nephrotoxicity was defined as creatinine values increasing 100% or more over pretreatment levels in pediatric patients, and creatinine values increasing 100% or more over pretreatment levels in adult patients, provided the peak creatinine concentration was > 1.2 mg/dL. Hypokalemia was defined as potassium levels ≤ 2.5 mmol/L any time during treatment.

Incidence of nephrotoxicity, mean peak serum creatinine concentration, mean change from baseline in serum creatinine, and incidence of hypokalemia in the double-blind, randomized study were lower in the Am B isome group as summarized in the following table: vs. amphotericin B (0.6 mg/kg/day) on renal function in adult patients enrolled in this study is illustrated in the following figure: In empirical therapy study 97-0-034, the incidence of nephrotoxicity as measured by increases of serum creatinine from baseline was significantly lower for patients administered Am B isome (individual dose groups and combined) compared with amphotericin B lipid complex. Incidence of The following graph shows the average serum creatinine concentrations in the compassionate use study and shows that there is a drop from pretreatment concentrations for all patients, especially those with elevated (greater than 1.7 mg/dL) pretreatment creatinine concentrations. The incidence of nephrotoxicity in Study 94-0-013 comparative trial in cryptococcal meningitis was lower in the Am B isome groups as shown in the following table: Laboratory Evidence of Mean Change in Creatinine Over Time in Study 94-0-002 Mean Creatine Concentrations Over Time

Drug Interactions No formal clinical studies of drug interactions have been conducted with Am B isome; however, the following drugs are known to interact with amphotericin B and may interact with Am B isome: Antineoplastic Agents Concurrent use of antineoplastic agents may enhance the potential for renal toxicity, bronchospasm, and hypotension. Antineoplastic agents should be given concomitantly with caution. Corticosteroids and Corticotropin (ACTH) Concurrent use of corticosteroids and ACTH may potentiate hypokalemia, which could predispose the patient to cardiac dysfunction.

If used concomitantly, serum electrolytes and cardiac function should be closely monitored. Digitalis Glycosides Concurrent use may induce hypokalemia and may potentiate digitalis toxicity. When administered concomitantly, serum potassium levels should be closely monitored.

Flucytosine Concurrent use of flucytosine may increase the toxicity of flucytosine by possibly increasing its cellular uptake and/or impairing its renal excretion. Azoles (e.g., ketoconazole, miconazole, clotrimazole, fluconazole, etc.) In vitro and in vivo animal studies of the combination of amphotericin B and imidazoles suggest that imidazoles may induce fungal resistance to amphotericin B. Combination therapy should be administered with caution, especially in immunocompromised patients.

Leukocyte Transfusions Acute pulmonary toxicity has been reported in patients simultaneously receiving intravenous amphotericin B and leukocyte transfusions. Other Nephrotoxic Medications Concurrent use of amphotericin B and other nephrotoxic medications may enhance the potential for drug-induced renal toxicity. Intensive monitoring of renal function is recommended in patients requiring any combination of nephrotoxic medications.

Skeletal Muscle Relaxants Amphotericin B-induced hypokalemia may enhance the curariform effect of skeletal muscle relaxants (e.g. tubocurarine) due to hypokalemia.

Pediatric Use Pediatric patients, age 1 month to 16 years, with presumed fungal infection (empirical therapy), confirmed systemic fungal infections or with visceral leishmaniasis have been successfully treated with Am B isome. In studies which included 302 pediatric patients administered Am B isome, there was no evidence of any differences in efficacy or safety of Am B isome compared to adults. Since pediatric patients have received Am B isome at doses comparable to those used in adults on a per kilogram body weight basis, no dosage adjustment is required in this population.

Safety and effectiveness in pediatric patients below the age of one month have not been established (See DESCRIPTION OF CLINICAL STUDIES - Empirical Therapy in Febrile Neutropenic Patients and DOSAGE AND ADMINISTRATION ).

Am B isome is contraindicated in those patients who have demonstrated or have a known hypersensitivity to amphotericin B deoxycholate or any other constituents of the product unless, in the opinion of the treating physician, the benefit of therapy outweighs the risk.

The toxicity of Am B isome due to overdose has not been defined. Repeated daily doses up to 10 mg/kg in pediatric patients and 15 mg/kg in adult patients have been administered in clinical trials with no reported dose-related toxicity. Management If overdosage should occur, cease administration immediately.

Symptomatic supportive measures should be instituted. Particular attention should be given to monitoring renal function. Hemodialysis or peritoneal dialysis do not appear to significantly affect the elimination of Am B isome.