COMPOSITION FUNGIZONE Intravenous (Amphotericin B for injection) is a sterile lyophilized powder providing 50 mg amphotericin B and 41 mg sodium desoxycholate with 20,2 mg sodium phosphate as a buffer, per vial. At the time of manufacture, the air in the container is replaced by nitrogen.
PHARMACOLOGICAL CLASSIFICATION Category A 20.1.7 (Antifungal Antibiotics).
Microbiology Amphotericin B shows a high order of in vitro activity against many species of fungi. Histoplasma capsulatum, Coccidioides immitis, Candida species, Blastomyces dermatitidis, Rhodotorula, Cryptococcus neoformans, Sporothrix schenckii, Mucor mucedo and Aspergillus fumigatus are all inhibited by concentrations of amphotericin B ranging from 0,03 to 1,0 micrograms/mL in vitro. The antibiotic is without effect on bacteria, rickettsiae and viruses. Human Pharmacology Amphotericin B is fungistatic rather than fungicidal in concentrations obtainable in body fluids. It probably acts by binding to sterols in the fungal cell membrane of susceptible fungi with a resultant change in membrane permeability which allows leakage of intracellular components. Mammalian cell membranes also contain sterols and it has been suggested that the damage to human cells (toxicity) and damage to fungal cells (antibiotic effect) may share common mechanisms.
Average peak blood levels of 0,5 to 2 micrograms/mL are found in adults given repeated doses of approximately 0,5 mg/kg/day. An elimination half-life of approximately 15 days follows an initial plasma half-life of about 24 hours. Amphotericin B circulating in plasma is highly bound (>90%) to plasma proteins and is poorly dialyzable. Approximately two thirds of concurrent plasma concentrations have been detected in fluids from inflamed pleura, peritoneum, synovium, and acqueous humor. Concentrations in the cerebrospinal fluid seldom exceed 2,5 percent of those in the plasma or are non-detectable. Little amphotericin B penetrates into vitreous humor or normal amneotic fluid.
Amphotericin B is excreted very slowly (over weeks to months) by the kidneys with two to five percent of a given dose being excreted in the biologically active form.
After treatment is discontinued, the drug can be detected in the urine for at least seven weeks due to the slow disappearance of the drug.
INDICATIONS FUNGIZONE Intravenous should be administered primarily to patients with progressive, potentially fatal infections. This potent drug should not be used to treat the common non-invasive fungal infections such as oral thrush, vaginal cadidiasis and oesophageal candidiasis in pateints with normal neutrophil counts.
FUNGIZONE Intravenous is specifically intended to treat potentially life-threateing fungal infections:
cryptococcosis (torulosis); North American blastomycosis; the disseminated forms of moniliasis (candidiasis), coccidioidomycosis and histoplasmosis; mucormycosis (phycomycosis) caused by susceptible species of the genera Mucor, Rhizopus, Absidia, Entomophthora, and Basidiobolus; sporotrichosis (Sporothrix schenckii); aspergillosis (Aspergillus fumigatus).
Amphotericin B may be helpful in the treatment of American mucocutaneous leishmaniasis, but is not the drug of choice in primary therapy.
CONTRA-INDICATIONS This product is contra-indicated in patients who have shown hypersensitivity to it unless, in the opinion of the physician, the condition requiring treatment is life-threatening and amenable only to amphotericin B therapy. Usage in Pregnancy Safety for use in pregnancy has not been established; therefore, it should be used during pregnancy only if the possible benefits to be derivedoutweigh the potential risks involved. Nursing Mothers It is not known whether amphotericin B is excreted in human milk. Paediatric Use Safety and effectiveness in paediatric patients have not been established through adequate and well-controlled studies.
WARNINGS This drug should be used primarily for treatment of patients with progressive and potentially fatal fungal infections; it should not be used to treat the common clinically inapparent forms of fungal disease which show only positive skin or serologic tests.
Amphotericin B may be the only effective treatment available for a potentially fatal disease. In each case, therefore, its possible life saving effect must be balanced against its untoward and dangerous effects.
DOSAGE AND DIRECTIONS FOR USE FUNGIZONE Intravenous should be administered by slow intravenous infusion. Intravenous infusion should be given over a period of approximately two to six hours observing the usual precautions for intravenous therapy. The recommended concentration for intravenous infusion is 0,1 mg/mL (1 mg/10 mL).
Dosage must be adjusted to the specific requirements of each patient since tolerance to amphotericin B varies individually. Therapy is usually instituted with a daily dose of 0,25 mg/kg of body mass and gradually increased as tolerance permits.
Though not proven to be a reliable predictor of intolerance, an initial test dose (1 mg in 20 mL of 5% dextrose solution) administered intravenously over 20 to 30 minutes may be preferred.
The patient's temperature, pulse, respiration, and blood pressure should be recorded every 30 minutes for 2 to 4 hours. (Note: See 'Intolerance Therapy' under 'SIDE EFFECTS AND SPECIAL PRECAUTIONS'). A patient with severe rapidly progressing fungal infection, with good cardiopulmonary and renal function and who tolerates the test dose without a severe reaction, may then receive 0,3 mg/kg amphotericin B intravenously over a period of 2 to 6 hours. A smaller second dose, ie. 5 to 10 mg, is recommended for the patient with cardiopulmonary or renal impairment or severe reaction to the test dose.
Doses may gradually be increased by 5 to 10 mg per day to a final daily dosage of 0,5 to 0,7 mg/kg. There are insufficient data presently available to define total dosage requirements and duration of treatment necessary for eradication of mycoses such as mucormycosis. The optimal dose is unknown. Total daily dosage may range up to 1,0 mg/kg per day, or up to 1,5 mg/kg on alternate days, in severe infections caused by less susceptible pathogens. Several months of therapy are usually necessary;a shorter period of therapy may produce an inadequate response and lead to relapse. Caution
Under no circumstances should a total daily dosage of 1,5 mg/kg be exceeded. Amphotericin B overdoses can result in cardio-respiratory arrest (See KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT). The duration of treatment for deep-seated mycoses may be 6 to 12 weeks or longer. Note: If symptoms of intolerance (See SIDE EFFECTS) develop, they may be made less severe by additional therapy methods (See SPECIAL PRECAUTIONS - Concomitant Medication: Intolerance Therapy).
Rhinocerebral mucormycosis, a fulminating disease, generally occurs in association with diabetic ketoacidosis. It is imperative that rapid restoration of diabetic control be achieved in order for treatment with amphotericin B to be successful. Since rhinocerebral mucormycosis usually follows a rapidly fatal course, the therapeutic approach must necessarily be more aggressive than that used in more indolent mycoses and amphotericin B therapy doses typically range from 0,7 to 1,5 mg/kg per day. Reconstitution of solutions: An initial concentrate of 5 mg amphotericin B per mL is first prepared by rapidly injecting 10 mL Sterile Water for Injection without a bacteriostatic agent directly into the lyophilized cake, using a sterile needle (minimum 20 gauge) and syringe. Shake the vial immediately until the colloidal solution is clear. The infusion solution is prepared by taking sufficient concentrate and diluting this with 5% Dextrose Injection such that the final concentrate is 0,1 mg amphotericin B per mL. The pH of the Dextrose Injection should be ascertained before use and should be above 4,2. Commercial Dextrose Injection usually has a pH above 4,2; however, if it is below 4,2, then 1 or 2 mL of buffer should be added to the Dextrose Injection before it is used to dilute the concentrated solution of amphotericin B. The recommended buffer has the following composition:
Dibasic sodium phosphate (anhydrous)
Monobasic sodium phosphate (anhydrous)
Water for Injection
qs 100,0 mL
The buffer should be sterilized before it is added to the Dextrose Injection, either by filtration through a bacterial retentive stone, mat, or membrane, or by autoclaving for 30 minutes at 103,4 kPa pressure (121°C). Caution
Aseptic technique must be observed strictly in the preparation of the buffer and infusion, since no preservative or bacteriostatic agent is present in the antibiotic or in the materials used to prepare it for administration. All entries into the vial or into the diluents must be made with a sterile needle.
Do not reconstitute with saline solutions. The use of any diluent other than the ones recommended or the presence of a bacteriostatic agent (e.g., benzyl alcohol) in the diluent may cause precipitation of the antibiotic. Do not use the initial concentrate or the infusion solution if there is any evidence of precipitation or foreign matter in either one. Since FUNGIZONE Intravenous is a colloidal dispersion, the use of membrane filters in intravenous infusion lines is not recommended; significant amounts of the active ingredient may be removed by these filters, which are capable of retaining particles in the micron range.
SIDE EFFECTS AND SPECIAL PRECAUTIONS The side effects most commonly observed are: General(body as a whole): fever (sometimes accompanied by shaking chills usually occurring within 15 to 20 minutes after initiation of treatment); malaise; loss of mass. Cardiopulmonary: hypotension, tachypnoea. Gastrointestinal: anorexia; nausea; vomiting; diarrhoea; dyspepsia; cramping epigastric pain. Haematologic: normochromic, normocytic anemia. Local: pain at the injection site with or without phlebitis or thrombophlebitis. Musculoskeletal: generalized pain, including muscle and joint pains. Neurologic: headache. Renal: decreased renal function and renal function abnormalities including: azotemia, increased serum creatinine, hypokalemia, hyposthenuria, renal tubular acidosis, and nephrocalcinosis. These usually improve with interruption of therapy. However, some permanent impairment often occurs, especially in those patients receiving large cumulative amounts (over 5g) of amphotericin B.
The following adverse reactions have also been reported: General (body as a whole): flushing. Allergic: anaphylactoid and other allergic reactions. Cardiovascular: cardiac arrest; arrhythmias, including ventricular fibrillation; cardiac failure; hypertension; shock. Dermatologic: rash, in particular maculopapular; pruritis. Less frequent reports of Stevens-Johnson syndrome have been received during post-marketing surveillance. Gastrointestinal: liver function test abnormalities; jaundice; acute liver failure; haemorrhagic gastroenteritis; melaena. Haematologic: agranulocytosis; coagulation defects; thrombocytopenia; leukopenia; eosinophilia; leukocytosis. Neurologic: convulsions; hearing loss; tinnitus; transient vertigo; blurred vision or diplopia; peripheral neuropathy; encephalopathy (See 'Special Precautions'); other neurologic symptoms. Pulmonary: dyspnea, bronchospasm; non-cardiac pulmonary edema; hypersensitivity pneumonitis. Renal: acute renal failure; anuria; oliguria. Altered serum electrolytes: hypomagnesaemia, hypo- and hyperkalaemia and hypocalcaemia.
Special Precautions Amphotericin B should be administered intravenously only, and be given to patients under close clinical supervision by medically trained personnel. It should be reserved for treatment of patients with progressive, potentially life-threatening fungal infections. Hence, amphotericin B should be used parenterally only in hospitalized patients or those under close clinical observation by medically trained personnel and should be reserved for those patients in whom a diagnosis of the progressive, potentially fatal forms of susceptible mycotic infections has been made. Acute reactions including chills, fever, anorexia, nausea, vomiting, headache, myalgia, arthralgia, and hypotension are common when amphotericin B is given intravenously.
Rapid intravenous infusion, over less than one hour, particularly in patients with renal insufficiency, has been associated with hyperkalemia and arrhythmias, and should, therefore, be avoided (see DOSAGE AND DIRECTIONS FOR USE).
Leukoencephalopathy has been reported following use of amphotericin B in patients who received total body irradiation.
Renal function should be monitored frequently during amphotericin B therapy;
Laboratory facilities must be available to perform blood urea nitrogen and serum creatinine or endogenous creatinine clearance tests. These determinations should be made at least weekly during therapy. If the blood urea nitrogen exceeds 40 mg per 100 mL or the serum creatinine exceeds 3,0 mg per 100 mL the drug should be discontinued or the dosage markedly reduced until renal function is improved.
It is also advisable to monitor liver function, as well as weekly haemograms, and serum electrolytes (particularly magnesium and potassium).
Whenever medication is interrupted for a period longer than 7 days, therapy should be resumed by starting with the lowest dosage level, i.e. 0,25 mg/kg of body mass, and increased gradually as outlined under "DOSAGE AND DIRECTIONS FOR USE". Concomitant Medication Corticosteroids should not be administered concomitantly unless they are necessary to control drug reactions. Other nephrotoxic antibiotics and antineoplastic agents such as nitrogen mustard should not be given concomitantly except with great caution. Intolerance Therapy While some patients may tolerate full intravenous doses of amphotericin B without difficulty, most will exhibit some intolerance, often at less than the full therapeutic dosage. They may be made less severe by giving aspirin, other antipyretics (e.g. paracetamol), antihistamines or antiemetics. Pethidine (25 mg to 50 mg intravenously) has been used in some patients to decrease the duration or intensity of shaking chills and fever following amphotericin B therapy.
Administration of the drug on alternate days may decrease anorexia and phlebitis. Intravenous administration of small doses of adrenal corticosteroids just prior to or during the amphotericin B infusion may decrease febrile reactions. The dosage and duration of such corticosteroid therapy should be kept to a minimum. Adding a small amount of heparin to the infusion (1000 units per infusion), rotation of the injection site, and the use of a paediatric scalp-vein needle may lessen the incidence of thrombophlebitis. Extravasation may cause chemical irritation. Drug Interactions When administered concurrently, the following drugs may interact with amphotericin B:
Other nephrotoxic medications - e.g., cisplatin, pentamidine, aminoglycosides, and cyclosporine, may enhance the potential for renal toxicity, and thus should be used concomitantly only with great caution.
Corticosteroids and Corticotropin (ACTH)- may potentiate amphotericin B-induced hypokalemia.
Agents whose effects or toxicity may be increased by hypokalemia - e.g., digitalis glycosides, skeletal muscle relaxants and antiarrhythmic agents.
Flucytosine-concomitant use may increase the toxicity of flucytosine possibly by increasing its cellular uptake and/or impairing its renal excretion.
Leukocyte transfusions - though not observed in all studies, acute pulmonary reactions have been observed in patients given amphotericin B during or shortly after leukocyte transfusions, thus it is advisable to separate these infusions as far as possible and to monitor pulmonary function.
Imidazoles - (e.g. Ketocaonazole, miconazole, clotrimazole, fluconazole). In vitro studies and animal studies with the combination of amphotericin B and imadozoles suggest that imadazoles may induce fungal resistance to amphotericin B. Combination therapy should be administered with caution, especially in immunocompromised patients.
KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT Treatment of overdosage should be symptomatic and supportive. Amphotericin B overdoses can result in cardio-respiratory arrest. If an overdose is suspected, discontinue therapy and monitor the patient's clinical status (e.g., cardio-respiratory, renal and liver function, hematologic status, serum electrolytes) and administer supportive therapy as required. Amphotericin B is not hemodialyzable. Prior to reinstituting therapy, the patient's condition should be stabilized (including correction of electrolyte deficiencies, etc.).
IDENTIFICATION Injection: Dry: A yellow to orange, fine fluffy powder, or a dry cake.
Reconstituted product: A collodial dispersion practically free from visible evidence of contamination.
PRESENTATION FUNGIZONE Intravenous is supplied in clear vials as a sterile lyophilized powder providing 50 mg amphotericin B and 41 mg sodium desoxycholate with 20,2 mg sodium phosphate as a buffer.
STORAGE INSTRUCTIONS FUNGIZONE Intravenous in powder form should be stored in the refrigerator, (2-8°C) protected against exposure to light. The concentrate, ie (5 mg amphotericin B per mL after reconstitution of the powder with 10 mL Sterile Water for Injection) should immediately be prepared for intravenous infusion. Solutions prepared for intravenous infusion (0,1 mg or less amphotericin B per mL) should be used promptly after preparation and should be protected from light during administration. Any unused concentrate should be discarded.
KEEP OUT OF REACH OF CHILDREN.
REGISTRATION NUMBER A/20.1.7/150
NAME AND BUSINESS ADDRESS OF APPLICANT BRISTOL-MYERS SQUIBB (PTY) LTD*
47 Van Buuren Road
DATE OF PUBLICATION OF THIS PACKAGE INSERT 20 May 2000
*Authorised user of the TM FUNGIZONE.
(Updated according to CPLP 8 October 1999)
Updated on this site: June 2005
Source: Pharmaceutical Industry