Acyclovir

INDICATIONS AND USAGE Herpes Simplex Infections in Immunocompromised Patients Acyclovir for Injection is indicated for the treatment of initial and recurrent mucosal and cutaneous herpes simplex (HSV-1 and HSV-2) in immunocompromised patients. Initial Episodes of Herpes Genitalis Acyclovir for Injection is indicated for the treatment of severe initial clinical episodes of herpes genitalis in immunocompetent patients. Herpes Simplex Encephalitis Acyclovir for Injection is indicated for the treatment of herpes simplex encephalitis. Neonatal Herpes Simplex Virus Infection Acyclovir for Injection is indicated for the treatment of neonatal herpes infections. Varicella-Zoster Infections in Immunocompromised Patients Acyclovir for Injection is indicated for the treatment of varicella-zoster (shingles) infections in immunocompromised patients.

DOSAGE AND ADMINISTRATION CAUTION—RAPID OR BOLUS INTRAVENOUS INJECTION MUST BE AVOIDED (see WARNINGS and PRECAUTIONS ). INTRAMUSCULAR OR SUBCUTANEOUS INJECTION MUST BE AVOIDED (see WARNINGS ). Therapy should be initiated as early as possible following onset of signs and symptoms of herpes infections. A maximum dose equivalent to 20 mg/kg every 8 hours should not be exceeded for any patient. Dosage Herpes Simplex Infections Mucosal and Cutaneous Herpes Simplex (HSV-1 and HSV-2) Infections in Immunocompromised Patients Adults and Adolescents (12 years of age and older): 5 mg/kg infused at a constant rate over 1 hour, every 8 hours for 7 days. Pediatrics (Under 12 years of age): 10 mg/kg infused at a constant rate over 1 hour, every 8 hours for 7 days. Severe Initial Clinical Episodes of Herpes Genitalis Adults and Adolescents (12 years of age and older): 5 mg/kg infused at a constant rate over 1 hour, every 8 hours for 5 days. Herpes Simplex Encephalitis Adults and Adolescents (12 years of age and older) : 10 mg/kg infused at a constant rate over 1 hour, every 8 hours for 10 days. Pediatrics (3 months to 12 years of age): 20 mg/kg infused at a constant rate over 1 hour, every 8 hours for 10 days . Neonatal Herpes Simplex Virus Infections (Birth to 3 months) 10 mg/kg infused at a constant rate over 1 hour, every 8 hours for 10 days. In neonatal herpes simplex infections, doses of 15 mg/kg or 20 mg/kg (infused at a constant rate over 1 hour every 8 hours) have been used; the safety and efficacy of these doses are not known. Varicella Zoster Infections Zoster in Immunocompromised Patients Adults and Adolescents (12 years of age and older): 10 mg/kg infused at a constant rate over 1 hour, every 8 hours for 7 days. Pediatrics (Under 12 years of age): 20 mg/kg infused at a constant rate over 1 hour, every 8 hours for 7 days. Obese Patients: Obese patients should be dosed at the recommended adult dose using Ideal Body Weight. Patients with Acute or Chronic Renal Impairment Refer to DOSAGE AND ADMINISTRATION for recommended doses, and adjust the dosing interval as indicated in Table 5. Table 5. Dosage Adjustments for Patients with Renal Impairment Creatinine Clearance (mL/min/1.73 m 2 ) Percent of Recommended Dose Dosing Interval (hours) >50 100% 8 25 - 50 100% 12 10 - 25 100% 24 0 - 10 50% 24 Hemodialysis For patients who require dialysis, the mean plasma half-life of acyclovir during hemodialysis is approximately 5 hours. This results in a 60% decrease in plasma concentrations following a 6-hour dialysis period. Therefore, the patient’s dosing schedule should be adjusted so that an additional dose is administered after each dialysis. Peritoneal Dialysis No supplemental dose appears to be necessary after adjustment of the dosing interval. Method of Preparation Each 10 mL vial contains acyclovir sodium equivalent to 500 mg of acyclovir. Each 20 mL vial contains acyclovir sodium equivalent to 1,000 mg of acyclovir. The contents of the vial should be dissolved in Sterile Water for Injection as follows: Contents of Vial Amount of Diluent 500 mg 10 mL 1,000 mg 20 mL The resulting solution in each case contains 50 mg acyclovir per mL (pH approximately 11). Shake the vial well to assure complete dissolution before measuring and transferring each individual dose. The reconstituted solution should be used within 12 hours. Refrigeration of reconstituted solution may result in the formation of a precipitate which will redissolve at room temperature. DO NOT USE BACTERIOSTATIC WATER FOR INJECTION CONTAINING BENZYL ALCOHOL OR PARABENS. Administration The calculated dose should then be removed and added to any appropriate intravenous solution at a volume selected for administration during each 1 hour infusion. Infusion concentrations of approximately 7 mg/mL or lower are recommended. In clinical studies, the average 70 kg adult received between 60 and 150 mL of fluid per dose. Higher concentrations (e.g., 10 mg/mL) may produce phlebitis or inflammati…

WARNINGS Acyclovir for Injection is intended for intravenous infusion only, and should not be administered topically, intramuscularly, orally, subcutaneously, or in the eye. Intravenous infusions must be given over a period of at least 1 hour to reduce the risk of renal tubular damage (see PRECAUTIONS and DOSAGE AND ADMINISTRATION ). Renal failure, in some cases resulting in death, has been observed with acyclovir therapy (see ADVERSE REACTIONS: Observed During Clinical Practice and OVERDOSAGE ). Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), which has resulted in death, has occurred in immunocompromised patients receiving acyclovir therapy.

CONTRAINDICATIONS Acyclovir for Injection is contraindicated for patients who develop hypersensitivity to acyclovir or valacyclovir.

Drug Interactions Coadministration of probenecid with acyclovir has been shown to increase the mean acyclovir half-life and the area under the concentration-time curve. Urinary excretion and renal clearance were correspondingly reduced. Drug Interactions See CLINICAL PHARMACOLOGY: Pharmacokinetics .

Pregnancy: Teratogenic Effects Acyclovir administered during organogenesis was not teratogenic in the mouse (450 mg/kg/day, PO), rabbit (50 mg/kg/day, SC and IV), or rat (50 mg/kg/day, SC). These exposures resulted in plasma levels the same as, 4 and 9, and 1and 2 times, respectively, human levels. There are no adequate and well-controlled studies in pregnant women. A prospective epidemiologic registry of acyclovir use during pregnancy was established in 1984 and completed in April 1999. There were 749 pregnancies followed in women exposed to systemic acyclovir during the first trimester of pregnancy resulting in 756 outcomes. The occurrence rate of birth defects approximates that found in the general population. However, the small size of the registry is insufficient to evaluate the risk for less common defects or to permit reliable or definitive conclusions regarding the safety of acyclovir in pregnant women and their developing fetuses. Acyclovir should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing Mothers Acyclovir concentrations have been documented in breast milk in 2 women following oral administration of acyclovir and ranged from 0.6 to 4.1 times corresponding plasma levels. These concentrations would potentially expose the nursing infant to a dose of acyclovir up to 0.3 mg/kg/day. Acyclovir should be administered to a nursing mother with caution and only when indicated.

ADVERSE REACTIONS The adverse reactions listed below have been observed in controlled and uncontrolled clinical trials in approximately 700 patients who received acyclovir at approximately 5 mg/kg (250 mg/m 2 ) three times daily, and approximately 300 patients who received approximately 10 mg/kg (500 mg/m 2 ) three times daily. The most frequent adverse reactions reported during administration of acyclovir were inflammation or phlebitis at the injection site in approximately 9% of the patients, and transient elevations of serum creatinine or BUN in 5% to 10% (the higher incidence occurred usually following rapid [less than 10 minutes] intravenous infusion). Nausea and/or vomiting occurred in approximately 7% of the patients (the majority occurring in nonhospitalized patients who received 10 mg/kg). Itching, rash, or hives occurred in approximately 2% of patients. Elevation of transaminases occurred in 1% to 2% of patients. The following hematologic abnormalities occurred at a frequency of less than 1%: anemia, neutropenia, thrombocytopenia, thrombocytosis, leukocytosis, and neutrophilia. In addition, anorexia and hematuria were observed. Observed During Clinical Practice In addition to adverse events reported from clinical trials, the following events have been identified during post-approval use of Acyclovir for Injection in clinical practice. Because they are reported voluntarily from a population of unknown size, estimates of frequency cannot be made. These events have been chosen for inclusion due to either their seriousness, frequency of reporting, potential causal connection to acyclovir, or a combination of these factors. General: Anaphylaxis, angioedema, fatigue, fever, headache, pain, peripheral edema. Digestive: Abdominal pain, diarrhea, gastrointestinal distress, nausea. Cardiovascular: Hypotension. Hematologic and Lymphatic: Disseminated intravascular coagulation, hemolysis, leukocytoclastic vasculitis, leukopenia, lymphadenopathy. Hepatobiliary Tract and Pancreas : Elevated liver function tests, hepatitis, hyperbilirubinemia, jaundice. Musculoskeletal: Myalgia. Nervous: Aggressive behavior, agitation, ataxia, coma, confusion, delirium, dizziness, dysarthria, encephalopathy, hallucinations, obtundation, paresthesia, psychosis, seizure, somnolence, tremor. These symptoms may be marked, particularly in older adults (see PRECAUTIONS ). Skin: Alopecia, erythema multiforme, photosensitive rash, pruritus, rash, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria. Severe local inflammatory reactions, including tissue necrosis, have occurred following infusion of acyclovir into extravascular tissues. Special Senses: Visual abnormalities. Urogenital: Renal failure, elevated blood urea nitrogen, elevated creatinine (see WARNINGS ). To report SUSPECTED ADVERSE REACTIONS, contact Hikma Pharmaceuticals USA Inc. at 1-877-845-0689 or the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.