Rx ONLY

FOR INTRAVENOUS INFUSION ONLY

DESCRIPTION

Ganciclovir is a synthetic guanine derivative active against cytomegalovirus (CMV).

Ganciclovir for Injection USP is available as sterile Iyophilized powder in strength of 500 mg per vial for intravenous administration only. Each vial of ganciclovir IV contains the equivalent of 500 mg ganciclovir as the sodium salt (45 mg sodium). Reconstitution with 10 mL of Sterile Water for Injection, USP, yields a solution with pH 11 and a ganciclovir concentration of approximately 50 mg/mL. Further dilution in an appropriate intravenous solution must be performed before infusion (see DOSAGE AND ADMINISTRATION).

Ganciclovir, when formulated as monosodium salt, in the IV dosage form, is a white to off-white lyophilized powder with the molecular formula of C9H12N5NaO4 and a molecular weight of 277.22. The chemical name for ganciclovir sodium is 9-[[2-hydroxy-1-(hydroxymethyl)ethoxy] methyl] guanine, monosodium salt. Ganciclovir is a polar hydrophilic compound with a solubility of 2.6 mg/mL in water at 25°C and n-octanol/water partition coefficient of 0.022. The pKas for ganciclovir are 2.2 and 9.4. The lyophilized powder has an aqueous solubility of greater than 50 mg/mL at 25°C. At physiological pH, ganciclovir sodium exists as the un-ionized form with a solubility of approximately 6 mg/mL at 37°C.

The chemical structure of ganciclovir sodium is:

All doses in this insert are specified in terms of ganciclovir.

VIROLOGY

Mechanism of Action: Ganciclovir is an acyclic nucleoside analogue of 2'-deoxyguanosine that inhibits replication of herpes viruses. Ganciclovir has been shown to be active against cytomegalovirus (CMV) and herpes simplex virus (HSV) in human clinical studies.

To achieve anti-CMV activity, ganciclovir is phosphorylated first to the monophosphate form by a CMV-encoded (UL97 gene) protein kinase homologue, then to the di- and triphosphate forms by cellular kinases. Ganciclovir triphosphate concentrations may be 100-fold greater in CMV-infected than in uninfected cells, indicating preferential phosphorylation in infected cells. Ganciclovir triphosphate, once formed, persists for days in the CMV-infected cell. Ganciclovir triphosphate is believed to inhibit viral DNA synthesis by (1) competitive inhibition of viral DNA polymerases; and (2) incorporation into viral DNA, resulting in eventual termination of viral DNA elongation.

Antiviral Activity: The median concentration of ganciclovir that inhibits CMV replication (IC50) in vitro (laboratory strains or clinical isolates) has ranged from 0.02 to 3.48 mcg/mL. Ganciclovir inhibits mammalian cell proliferation (CIC50) in vitro at higher concentrations ranging from 30 to 725 mcg/mL. Bone marrow-derived colony-forming cells are more sensitive (CIC50 0.028 to 0.7 mcg/mL). The relationship of in vitro sensitivity of CMV to ganciclovir and clinical response has not been established.

Clinical Antiviral Effect of Ganciclovir IV: In a study of ganciclovir IV treatment of life- or sight-threatening CMV disease in immunocompromised patients, 121 of 314 patients had CMV cultured within 7 days prior to treatment and sequential posttreatment viral cultures of urine, blood, throat and/or semen. As judged by conversion to culture negativity, or a greater than 100-fold decrease in in vitro CMV titer, at least 83% of patients had a virologic response with a median response time of 7 to 15 days.

Antiviral activity of ganciclovir IV was demonstrated in two randomized studies for the prevention of CMV disease in transplant recipients (see Table 1).

* CMV seropositive or receiving graft from seropositive donor

† 5 mg/kg bid for 14 days followed by 6 mg/kg qd for 5 days/week for 14 days

‡ 5 mg/kg bid for 7 days followed by 5 mg/kg qd until day 100 posttransplant

Viral Resistance: The current working definition of CMV resistance to ganciclovir in in vitro assays is IC50 >3 mcg/mL (12 μM). CMV resistance to ganciclovir has been observed in individuals with AIDS and CMV retinitis who have never received ganciclovir therapy. Viral resistance has also been observed in patients receiving prolonged treatment for CMV retinitis with ganciclovir IV.

The possibility of viral resistance should be considered in patients who show poor clinical response or experience persistent viral excretion during therapy. The principal mechanism of resistance to ganciclovir in CMV is the decreased ability to form the active triphosphate moiety; resistant viruses have been described that contain mutations in the UL97 gene of CMV that controls phosphorylation of ganciclovir. Mutations in the viral DNA polymerase have also been reported to confer viral resistance to ganciclovir.

CLINICAL PHARMACOLOGY

Pharmacokinetics

BECAUSE THE MAJOR ELIMINATION PATHWAY FOR GANCICLOVIR IS RENAL, DOSAGE REDUCTIONS ACCORDING TO CREATININE CLEARANCE ARE REQUIRED FOR GANCICLOVIR IV. FOR DOSING INSTRUCTIONSIN PATIENTS WITH RENAL IMPAIRMENT, REFER TO DOSAGE AND ADMINISTRATION.

Absorption

At the end of a 1-hour intravenous infusion of 5 mg/kg ganciclovir, total AUC ranged between 22.1 ± 3.2 (n=16) and 26.8 ± 6.1 mcg•hr/mL (n=16) and Cmax, ranged between 8.27 ± 1.02 (n=16) and 9.0 ± 1.4 mcg/mL (n=16).

Distribution

 The steady-state volume of distribution of ganciclovir after intravenous administration was 0.74 ± 0.15 L/kg (n=98). Cerebrospinal fluid concentrations obtained 0.25 to 5.67 hours postdose in 3 patients who received 2.5 mg/kg ganciclovir intravenously q8h or q12h ranged from 0.31 to 0.68 mcg/mL representing 24% to 70% of the respective plasma concentrations. Binding to plasma proteins was 1% to 2% over ganciclovir concentrations of 0.5 and 51 mcg/mL.

Elimination

 When administered intravenously, ganciclovir exhibits linear pharmacokinetics over the range of 1.6 to 5.0 mg/kg. Renal excretion of unchanged drug by glomerular filtration and active tubular secretion is the major route of elimination of ganciclovir. In patients with normal renal function, 91.3 ± 5.0% (n=4) of intravenously administered ganciclovir was recovered unmetabolized in the urine. Systemic clearance of intravenously administered ganciclovir was 3.52 ± 0.80 mL/min/kg (n=98) while renal clearance was 3.20 ± 0.80 mL/min/kg (n=47), accounting for 91 ± 11% of the systemic clearance (n=47). Half-life was 3.5 ± 0.9 hours (n=98) following IV administration.

Special Populations

Renal Impairment: The pharmacokinetics following intravenous administration of ganciclovir IV solution were evaluated in 10 immunocompromised patients with renal impairment who received doses ranging from 1.25 to 5 mg/kg.

Based on these observations, it is necessary to modify the dosage of ganciclovir in patients with renal impairment (see DOSAGE AND ADMINISTRATION).

Hemodialysis reduces plasma concentrations of ganciclovir by about 50% after intravenous administration.

Race/Ethnicity and Gender: The effects of race/ethnicity and gender were studied in subjects receiving a dose regimen of 1000 mg every 8 hours. Although the numbers of blacks (16%) and Hispanics (20%) were small, there appeared to be a trend towards a lower steady-state Cmax and AUC0-8 in these subpopulations as compared to Caucasians. No definitive conclusions regarding gender differences could be made because of the small number of females (12%); however, no differences between males and females were observed.

Pediatrics: Ganciclovir pharmacokinetics were studied in 27 neonates, aged 2 to 49 days. At an intravenous dose of 4 mg/kg (n=14) or 6 mg/kg (n=13), the pharmacokinetic parameters were, respectively, Cmax of 5.5 ± 1.6 and 7.0 ± 1.6 mcg/mL, systemic clearance of 3.14 ± 1.75 and 3.56 ± 1.27 mL/min/kg, and t1/2 of 2.4 hours (harmonic mean) for both.

Ganciclovir pharmacokinetics were also studied in 10 pediatric patients, aged 9 months to 12 years. The pharmacokinetic characteristics of ganciclovir were the same after single and multiple (q12h) intravenous doses (5 mg/kg). The steady-state volume of distribution was 0.64 ± 0.22 L/kg, Cmax was 7.9 ± 3.9 mcg/mL, systemic clearance was 4.7 ± 2.2 mL/min/kg, and t1/2 was 2.4 ± 0.7 hours. The pharmacokinetics of intravenous ganciclovir in pediatric patients are similar to those observed in adults.

Elderly: No studies have been conducted in adults older than 65 years of age.

INDICATIONS AND USAGE

Ganciclovir for injection is indicated for the treatment of CMV retinitis in immunocompromised patients, including patients with acquired immunodeficiency syndrome (AIDS). Ganciclovir for injection is also indicated for the prevention of CMV disease in transplant recipients at risk for CMV disease (see CLINICAL TRIALS).

SAFETY AND EFFICACY OF GANCICLOVIR HAVE NOT BEEN ESTABLISHED FOR CONGENITAL OR NEONATAL CMV DISEASE; NOR FOR THE TREATMENT OF ESTABLISHED CMV DISEASE OTHER THAN RETINITIS; NOR FOR USE IN NONIMMUNOCOMPROMISED INDIVIDUALS.

CLINICAL TRIALS

1. Treatment of CMV Retinitis

The diagnosis of CMV retinitis should be made by indirect ophthalmoscopy. Other conditions in the differential diagnosis of CMV retinitis include candidiasis, toxoplasmosis, histoplasmosis, retinal scars and cotton wool spots, any of which may produce a retinal appearance similar to CMV. For this reason it is essential that the diagnosis of CMV be established by an ophthalmologist familiar with the retinal presentation of these conditions. The diagnosis of CMV retinitis may be supported by culture of CMV from urine, blood, throat or other sites, but a negative CMV culture does not rule out CMV retinitis.

Studies With Ganciclovir IV: In a retrospective, non-randomized, single-center analysis of 41 patients with AIDS and CMV retinitis diagnosed by ophthalmologic examination between August 1983 and April 1988, treatment with ganciclovir IV solution resulted in a significant delay in mean (median) time to first retinitis progression compared to untreated controls [105 (71) days from diagnosis vs 35 (29) days from diagnosis]. Patients in this series received induction treatment of ganciclovir IV 5 mg/kg bid for 14 to 21 days followed by maintenance treatment with either 5 mg/kg once daily, 7 days per week or 6 mg/kg once daily, 5 days per week (see DOSAGE AND ADMINISTRATION).

In a controlled, randomized study conducted between February 1989 and December 1990,1 immediate treatment with ganciclovir IV was compared to delayed treatment in 42 patients with AIDS and peripheral CMV retinitis; 35 of 42 patients (13 in the immediate-treatment group and 22 in the delayed-treatment group) were included in the analysis of time to retinitis progression. Based on masked assessment of fundus photographs, the mean [95% CI] and median [95% CI] times to progression of retinitis were 66 days [39, 94] and 50 days [40, 84], respectively, in the immediate treatment group compared to 19 days [11, 27] and 13.5 days [8, 18], respectively, in the delayed-treatment group.

Studies Comparing Ganciclovir Capsules to Ganciclovir IV:

ICM 1653: In this randomized, open-label, parallel group trial, conducted between March 1991 and November 1992, patients with AIDS and newly diagnosed CMV retinitis received a 3-week induction course of ganciclovir IV solution, 5 mg/kg bid for 14 days followed by 5 mg/kg once daily for 1 additional week.2 Following the 21-day intravenous induction course, patients with stable CMV retinitis were randomized to receive 20 weeks of maintenance treatment with either ganciclovir IV solution, 5 mg/kg once daily, or ganciclovir capsules, 500 mg 6 times daily (3000 mg/day). The study showed that the mean [95% CI] and median [95% CI] times to progression of CMV retinitis, as assessed by masked reading of fundus photographs, were 57 days [44, 70] and 29 days [28, 43], respectively, for patients on oral therapy compared to 62 days [50, 73] and 49 days [29, 61], respectively, for patients on intravenous therapy. The difference [95% CI] in the mean time to progression between the oral and intravenous therapies (oral - IV) was -5 days [-22, 12]. See Figure 1 for comparison of the proportion of patients remaining free of progression over time.

ICM 1774: In this three-arm, randomized, open-label, parallel group trial, conducted between June 1991 and August 1993, patients with AIDS and stable CMV retinitis following from 4 weeks to 4 months of treatment with ganciclovir IV solution were randomized to receive maintenance treatment with ganciclovir IV solution, 5 mg/kg once daily, ganciclovir capsules, 500 mg 6 times daily, or ganciclovir capsules, 1000 mg tid for 20 weeks. The study showed that the mean [95% CI] and median [95% CI] times to progression of CMV retinitis, as assessed by masked reading of fundus photographs, were 54 days [48, 60] and 42 days [31, 54], respectively, for patients on oral therapy compared to 66 days [56, 76] and 54 days [41,69], respectively, for patients on intravenous therapy. The difference [95% CI] in the mean time to progression between the oral and intravenous therapies (oral - IV) was -12 days [-24, 0]. See Figure 2 for comparison of the proportion of patients remaining free of progression over time.

AVI 034: In this randomized, open-label, parallel group trial, conducted between June 1991 and February 1993, patients with AIDS and newly diagnosed (81%) or previously treated (19%) CMV retinitis who had tolerated 10 to 21 days of induction treatment with ganciclovir IV, 5 mg/kg twice daily, were randomized to receive 20 weeks of maintenance treatment with either ganciclovir capsules, 500 mg 6 times daily or ganciclovir IV solution, 5 mg/kg/day.3 The mean [95% CI] and median [95% CI] times to progression of CMV retinitis, as assessed by masked reading of fundus photographs, were 51 days [44, 57] and 41 days [31, 45], respectively, for patients on oral therapy compared to 62 days [52, 72] and 60 days [42, 83], respectively, for patients on intravenous therapy. The difference [95% CI] in the mean time to progression between the oral and intravenous therapies (oral - IV) was -11 days [-24, 1]. See Figure 3 for comparison of the proportion of patients remaining free of progression over time.

Comparison of other CMV retinitis outcomes between oral and IV formulations (development of bilateral retinitis, progression into Zone 1, and deterioration of visual acuity), while not definitive, showed no marked differences between treatment groups in these studies. Because of low event rates among these endpoints, these studies are underpowered to rule out significant differences in these endpoints.

2. Prevention of CMV Disease in Transplant Recipients

Ganciclovir IV was evaluated in three randomized, controlled trials of prevention of CMV disease in organ transplant recipients.

ICM 1496: In a randomized, double-blind, placebo-controlled study of 149 heart transplant recipients4 at risk for CMV infection (CMV seropositive or a seronegative recipient of an organ from a CMV seropositive donor), there was a statistically significant reduction in the overall incidence of CMV disease in patients treated with ganciclovir IV. Immediately posttransplant, patients received ganciclovir IV solution 5 mg/kg bid for 14 days followed by 6 mg/kg qd for 5 days/week for an additional 14 days. Twelve of the 76 (16%) patients treated with ganciclovir IV vs 31 of the 73 (43%) placebo-treated patients developed CMV disease during the 120-day posttransplant observation period. No significant differences in hematologic toxicities were seen between the two treatment groups (refer to Table 6 in ADVERSE REACTIONS).

ICM 1689: In a randomized, double-blind, placebo-controlled study of 72 bone marrow transplant recipients5 with asymptomatic CMV infection (CMV positive culture of urine, throat or blood) there was a statistically significant reduction in the incidence of CMV disease in patients treated with ganciclovir IV following successful hematopoietic engraftment.

Patients with virologic evidence of CMV infection received ganciclovir IV solution 5 mg/kg bid for 7 days followed by 5 mg/kg qd through day 100 posttransplant. One of the 37 (3%) patients treated with ganciclovir IV vs 15 of the 35 (43%) placebo-treated patients developed CMV disease during the study. At 6 months posttransplant, there continued to be a statistically significant reduction in the incidence of CMV disease in patients treated with ganciclovir IV. Six of 37 (16%) patients treated with ganciclovir IV vs 15 of the 35 (43%) placebo-treated patients developed disease through 6 months posttransplant. The overall rate of survival was statistically significantly higher in the group treated with ganciclovir IV, both at day 100 and day 180 posttransplant. Although the differences in hematologic toxicities were not statistically significant, the incidence of neutropenia was higher in the group treated with ganciclovir IV (refer to Table 6 in ADVERSE REACTIONS).

ICM 1570: A second, randomized, unblinded study evaluated 40 allogeneic bone marrow transplant recipients at risk for CMV disease.6 Patients underwent bronchoscopy and bronchoalveolar lavage (BAL) on day 35 posttransplant. Patients with histologic, immunologic or virologic evidence of CMV infection in the lung were then randomized to observation or treatment with ganciclovir IV solution (5 mg/kg bid for 14 days followed by 5 mg/kg qd 5 days/week until day 120). Four of 20 (20%) patients treated with ganciclovir IV and 14 of 20 (70%) control patients developed interstitial pneumonia. The incidence of CMV disease was significantly lower in the group treated with ganciclovir IV, consistent with the results observed in ICM 1689.

CONTRAINDICATIONS

Ganciclovir is contraindicated in patients with hypersensitivity to ganciclovir or acyclovir.

WARNINGS

PRECAUTIONS

ADVERSE REACTIONS

Adverse events that occurred during clinical trials of ganciclovir are summarized below, according to the participating study subject population.

Subjects with AIDS

 Three controlled, randomized, phase 3 trials comparing ganciclovir IV and ganciclovir capsules for maintenance treatment of CMV retinitis have been completed. During these trials, ganciclovir IV or ganciclovir capsules were prematurely discontinued in 9% of subjects because of adverse events. Laboratory data and adverse events reported during the conduct of these controlled trials are summarized below.

Laboratory Data:

Table 4. Selected Laboratory Abnormalities in Trials for Treatment of CMV Retinitis

Adverse Events: The following table shows selected adverse events reported in 5% or more of the subjects in three controlled clinical trials during treatment with either ganciclovir IV solution (5 mg/kg/day) or ganciclovir capsules (3000 mg/day), and in one controlled clinical trial with ganciclovir capsules (3000 mg/day).

Table 5. Selected Adverse Events Reported in ≥ 5% of Subjects in Three Randomized Phase 3 Studies Comparing Ganciclovir Capsules to Ganciclovir IV Solution for Maintenance Treatment of CMV Retinitis

The following events were frequently observed in clinical trials but occurred with equal or greater frequency in placebo-treated subjects: abdominal pain, nausea, flatulence, pneumonia, paresthesia, rash.

Retinal Detachment: Retinal detachment has been observed in subjects with CMV retinitis both before and after initiation of therapy with ganciclovir. Its relationship to therapy with ganciclovir is unknown. Retinal detachment occurred in 11% of patients treated with ganciclovir solution and in 8% of patients treated with ganciclovir capsules. Patients with CMV retinitis should have frequent ophthalmologic evaluations to monitor the status of their retinitis and to detect any other retinal pathology.

Transplant Recipients

There have been three controlled clinical trials of ganciclovir solution for the prevention of CMV disease in transplant recipients. Laboratory data and adverse events reported during these trials are summarized below.

Laboratory Data: The following table shows the frequency of granulocytopenia (neutropenia) and thrombocytopenia observed:

The following table shows the frequency of elevated serum creatinine values in these controlled clinical trials:

In these three trials, patients receiving ganciclovir IV solution had elevated serum creatinine levels when compared to those receiving placebo. Most patients in these studies also received cyclosporine. The mechanism of impairment of renal function is not known. However, careful monitoring of renal function during therapy with ganciclovir IV solution is essential, especially for those patients receiving concomitant agents that may cause nephrotoxicity.

General

 Other adverse events that were thought to be "probably" or "possibly" related to ganciclovir IV solution or ganciclovir capsules in controlled clinical studies in either subjects with AIDS or transplant recipients are listed below. These events all occurred in at least 3 subjects.

Body as a Whole: abdomen enlarged, asthenia, chest pain, edema, headache, injection site inflammation, malaise, pain

Digestive System: abnormal liver function test, aphthous stomatitis, constipation, dyspepsia, eructation

Hemic and Lymphatic System: pancytopenia

Respiratory System: cough increased, dyspnea

Nervous System: abnormal dreams, anxiety, confusion, depression, dizziness, dry mouth, insomnia, seizures, somnolence, thinking abnormal, tremor

Skin and Appendages: alopecia, dry skin

Special Senses: abnormal vision, taste perversion, tinnitus, vitreous disorder

Metabolic and Nutritional Disorders: creatinine increased, SGOT increased, SGPT increased, weight loss

Cardiovascular System: hypertension, phlebitis, vasodilatation

Urogenital System: creatinine clearance decreased, kidney failure, kidney function abnormal, urinary frequency

Musculoskeletal System: arthralgia, leg cramps, myalgia, myasthenia

The following adverse events reported in patients receiving ganciclovir may be potentially fatal: gastrointestinal perforation, multiple organ failure, pancreatitis and sepsis.

Adverse Events Reported During Postmarketing Experience With Ganciclovir

The following events have been identified during postapproval use of the drug. 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 the seriousness, frequency of reporting, the apparent causal connection or a combination of these factors: acidosis, allergic reaction, anaphylactic reaction, arthritis, bronchospasm, cardiac arrest, cardiac conduction abnormality, cataracts, cholelithiasis, cholestasis, congenital anomaly, dry eyes, dysesthesia, dysphasia, elevated triglyceride levels, encephalopathy, exfoliative dermatitis, extrapyramidal reaction, facial palsy, hallucinations, hemolytic anemia, hemolytic uremic syndrome, hepatic failure, hepatitis, hypercalcemia, hyponatremia, inappropriate serum ADH, infertility, intestinal ulceration, intracranial hypertension, irritability, loss of memory, loss of sense of smell, myelopathy, oculomotor nerve paralysis, peripheral ischemia, pulmonary fibrosis, renal tubular disorder, rhabdomyolysis, Stevens-Johnson syndrome, stroke, testicular hypotrophy, Torsades de Pointes, vasculitis, ventricular tachycardia

OVERDOSAGE

Overdosage with ganciclovir IV has been reported in 17 patients (13 adults and 4 children under 2 years of age). Five patients experienced no adverse events following overdosage at the following doses: 7 doses of 11 mg/kg over a 3-day period (adult), single dose of 3500 mg (adult), single dose of 500 mg (72.5 mg/kg) followed by 48 hours of peritoneal dialysis (4-month-old), single dose of approximately 60 mg/kg followed by exchange transfusion (18-month-old), 2 doses of 500 mg instead of 31 mg (21-month-old).

Irreversible pancytopenia developed in 1 adult with AIDS and CMV colitis after receiving 3000 mg of ganciclovir IV solution on each of 2 consecutive days. He experienced worsening GI symptoms and acute renal failure that required short-term dialysis. Pancytopenia developed and persisted until his death from a malignancy several months later. Other adverse events reported following overdosage included: persistent bone marrow suppression (1 adult with neutropenia and thrombocytopenia after a single dose of 6000 mg), reversible neutropenia or granulocytopenia (4 adults, overdoses ranging from 8 mg/kg daily for 4 days to a single dose of 25 mg/kg), hepatitis (1 adult receiving 10 mg/kg daily, and one 2 kg infant after a single 40 mg dose), renal toxicity (1 adult with transient worsening of hematuria after a single 500 mg dose, and 1 adult with elevated creatinine (5.2 mg/dL) after a single 5000 to 7000 mg dose), and seizure (1 adult with known seizure disorder after 3 days of 9 mg/kg). In addition, 1 adult received 0.4 mL (instead of 0.1 mL) ganciclovir IV solution by intravitreal injection, and experienced temporary loss of vision and central retinal artery occlusion secondary to increased intraocular pressure related to the injected fluid volume.

Since ganciclovir is dialyzable, dialysis may be useful in reducing serum concentrations. Adequate hydration should be maintained. The use of hematopoietic growth factors should be considered (see DOSAGE AND ADMINISTRATION: Renal Impairment).

DOSAGE AND ADMINISTRATION

CAUTION – DO NOT ADMINISTER GANCICLOVIR IV SOLUTION BY RAPID OR BOLUS INTRAVENOUS INJECTION. THE TOXICITY OF GANCICLOVIR IV MAY BE INCREASED AS A RESULT OF EXCESSIVE PLASMA LEVELS.

CAUTION – INTRAMUSCULAR OR SUBCUTANEOUS INJECTION OF RECONSTITUTED GANCICLOVIR IV SOLUTION MAY RESULT IN SEVERE TISSUE IRRITATION DUE TO HIGH pH (11).

Dosage: THE RECOMMENDED DOSE FOR GANCICLOVIR SHOULD NOT BE EXCEEDED. THE RECOMMENDED INFUSION RATE FOR GANCICLOVIR IV SOLUTION SHOULD NOT BE EXCEEDED.

For Treatment of CMV Retinitis in Patients With Normal Renal Function

1. Induction Treatment

The recommended initial dosage for patients with normal renal function is 5 mg/kg (given intravenously at a constant rate over 1 hour) every 12 hours for 14 to 21 days.

2. Maintenance Treatment

Following induction treatment, the recommended maintenance dosage of ganciclovir IV solution is 5 mg/kg given as a constant-rate intravenous infusion over 1 hour once daily, 7 days per week or 6 mg/kg once daily, 5 days per week.

For patients who experience progression of CMV retinitis while receiving maintenance treatment with ganciclovir, reinduction treatment is recommended.

For the Prevention of CMV Disease in Transplant Recipients With Normal Renal Function

 The recommended initial dosage of ganciclovir IV solution for patients with normal renal function is 5 mg/kg (given intravenously at a constant rate over 1 hour) every 12 hours for 7 to 14 days, followed by 5 mg/kg once daily, 7 days per week or 6 mg/kg once daily, 5 days per week.

The duration of treatment with ganciclovir in transplant recipients is dependent upon the duration and degree of immunosuppression. In controlled clinical trials in bone marrow allograft recipients, treatment with ganciclovir IV was continued until day 100 to 120 posttransplantation. CMV disease occurred in several patients who discontinued treatment with ganciclovir IV solution prematurely. In heart allograft recipients, the onset of newly diagnosed CMV disease occurred after treatment with ganciclovir IV was stopped at day 28 posttransplant, suggesting that continued dosing may be necessary to prevent late occurrence of CMV disease in this patient population (see INDICATIONS AND USAGE section for a more detailed discussion).

Renal Impairment

For patients with impairment of renal function, refer to Table 8 for recommended doses of ganciclovir IV solution and adjust the dosing interval as indicated:

Table 8. Dosing for Patients with Renal Impairment

*Creatinine clearance can be related to serum creatinine by the formulas given below.

Dosing for patients undergoing hemodialysis should not exceed 1.25 mg/kg 3 times per week, following each hemodialysis session. Ganciclovir IV should be given shortly after completion of the hemodialysis session, since hemodialysis has been shown to reduce plasma levels by approximately 50%.

Patient Monitoring

Due to the frequency of granulocytopenia, anemia and thrombocytopenia in patients receiving ganciclovir (see ADVERSE REACTIONS), it is recommended that complete blood counts and platelet counts be performed frequently, especially in patients in whom ganciclovir or other nucleoside analogues have previously resulted in cytopenia, or in whom neutrophil counts are less than 1000 cells/μL at the beginning of treatment. Patients should have serum creatinine or creatinine clearance values followed carefully to allow for dosage adjustments in renally impaired patients (see DOSAGE AND ADMINISTRATION).

Reduction of Dose

Dosage reductions in renally impaired patients are required for ganciclovir IV (see Renal Impairment). Dosage reductions should also be considered for those with neutropenia, anemia and/or thrombocytopenia (see ADVERSE REACTIONS). Ganciclovir should not be administered in patients with severe neutropenia (ANC less than 500/μL) or severe thrombocytopenia (platelets less than 25,000/μL).

Method of Preparation of Ganciclovir IV Solution

Each 10 mL clear glass vial contains ganciclovir sodium equivalent to 500 mg of ganciclovir and 45 mg of sodium. The contents of the vial should be prepared for administration in the following manner:

1. Reconstituted Solution:

a. Reconstitute lyophilized ganciclovir IV by injecting 10 mL of Sterile Water for Injection, USP, into the vial.

DO NOT USE BACTERIOSTATIC WATER FOR INJECTION CONTAINING PARABENS. IT IS INCOMPATIBLE WITH GANCICLOVIR IV AND MAY CAUSE PRECIPITATION.

b. Shake the vial to dissolve the drug.

c. Visually inspect the reconstituted solution for particulate matter and discoloration prior to proceeding with infusion solution. Discard the vial if particulate matter or discoloration is observed.

d. Reconstituted solution in the vial is stable at room temperature for 12 hours. It should not be refrigerated.

2. Infusion Solution:

Based on patient weight, the appropriate volume of the reconstituted solution (ganciclovir concentration 50 mg/mL) should be removed from the vial and added to an acceptable (see below) infusion fluid (typically 100 mL) for delivery over the course of 1 hour. Infusion concentrations greater than 10 mg/mL are not recommended. The following infusion fluids have been determined to be chemically and physically compatible with ganciclovir IV solution: 0.9% Sodium Chloride, 5% Dextrose, Ringer's Injection and Lactated Ringer's Injection.

Ganciclovir IV, when reconstituted with sterile water for injection, further diluted with 0.9% sodium chloride injection, and stored refrigerated at 5°C in polyvinyl chloride (PVC) bags, remains physically and chemically stable for 14 days.

However, because ganciclovir IV is reconstituted with nonbacteriostatic sterile water, it is recommended that the infusion solution be used within 12 hours of dilution to reduce the risk of bacterial contamination. The infusion should be refrigerated. Freezing is not recommended.

Handling and Disposal

  Caution should be exercised in the handling and preparation of solutions of ganciclovir. Solutions of ganciclovir IV are alkaline (pH 11). Avoid direct contact of the skin or mucous membranes with ganciclovir. If such contact occurs, wash thoroughly with soap and water; rinse eyes thoroughly with plain water.

Because ganciclovir shares some of the properties of antitumor agents (ie, carcinogenicity and mutagenicity), consideration should be given to handling and disposal according to guidelines issued for antineoplastic drugs. Several guidelines on this subject have been published.7-9

There is no general agreement that all of the procedures recommended in the guidelines are necessary or appropriate.

HOW SUPPLIED

Ganciclovir for Injection USP is supplied in 10 mL sterile vials, each containing ganciclovir sodium equivalent to 500 mg of ganciclovir, in cartons of 10 (NDC 55390-016-10).

Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.]

REFERENCES

1. Spector SA, Weingeis T, Pollard R, et al. A randomized, controlled study of intravenous ganciclovir therapy for cytomegalovirus peripheral retinitis in patients with AIDS. J Inf Dis. 1993; 168:557-563.

2. Drew WL, Ives D, Lalezari JP, et al. Oral ganciclovir as maintenance treatment for cytomegalovirus retinitis in patients with AIDS. New Engl J Med. 1995- 333:615-620.

3. The Oral Ganciclovir European and Australian Cooperative Study Group. lntravenous vs oral ganciclovir: European/Australian comparative study of efficacy and safety in the prevention of cytomegalovirus retinitis recurrence in patients with AIDS. AIDS. 1995; 9:471-477.

4. Merigan TC, Renlund DG, Keay S, et al. A controlled trial of ganciclovir to prevent cytomegalovirus disease after heart transplantation. New Engl J Med. 1992; 326:1182-1186.

5. Goodrich JM, Mori M, Gleaves CA, et al. Early treatment with ganciclovir to prevent cytomegalovirus disease after allogeneic bone marrow transplantation. New Engl J Med. 1991; 325:1601-1607.

6. Schmidt GM, Horak DA, Niland JC, et al. The City of Hope-Stanford-Syntex CMV Study Group. A randomized, controlled trial of prophylactic ganciclovir for cytomegalovirus pulmonary infection in recipients of allogeneic bone marrow transplants. New Engl J Med. 1991; 15:1005-1011.

7. Recommendations for the Safe Handling of Cytotoxic Drugs. US Department of Health and Human Services, National Institutes of Health, Bethesda, MD, September 1992. NIH Publication No. 92-2621.

8. American Society of Hospital Pharmacists technical assistance bulletin on handling cytotoxic and hazardous drugs. Am J Hosp Pharm. 1990; 47:1033-1049.

9. Controlling Occupational Exposures to Hazardous Drugs. US Department of Labor. Occupational Health and Safety Administration. OSHA Technical Manual. Section V - Chapter 3, September 22, 1995.

PACKAGE/LABEL PRINCIPAL DISPLAY PANEL

Vial Label 500 mg