Valganciclovir

12.1 Mechanism of Action Valganciclovir is an antiviral drug with activity against CMV [see Microbiology ( 12.4 )] .

1 INDICATIONS AND USAGE Valganciclovir for oral solution is a deoxynucleoside analogue cytomegalovirus (CMV) DNA polymerase inhibitor indicated for: Pediatric Patients ( 1.2 ) Prevention of CMV disease in kidney and heart transplant patients at high risk. 1.2 Pediatric Patients Prevention of CMV Disease: Valganciclovir is indicated for the prevention of CMV disease in kidney transplant patients (4 months to 16 years of age) and heart transplant patients (1 month to 16 years of age) at high risk [see Clinical Studies ( 14.2 )] .

2 DOSAGE AND ADMINISTRATION Pediatric Dosage ( 2.3 ) Prevention of CMV disease in kidney transplant patients 4 months to 16 years of age Dose once a day within 10 days of transplantation until 200 days post-transplantation according to dosage algorithm (note the calculation of creatinine clearance using a modified Schwartz formula in children) Prevention of CMV disease in heart transplant patients 1 month to 16 years of age Dose once a day within 10 days of transplantation until 100 days post-transplantation according to dosage algorithm (note the calculation of creatinine clearance using a modified Schwartz formula in children) Valganciclovir for oral solution should be taken with food. ( 2.1 , 12.3 ) 2.1 General Dosing Information Valganciclovir for oral solution should be taken with food [see Clinical Pharmacology ( 12.3 )] . Valganciclovir for oral solution (50 mg/mL) must be prepared by the pharmacist prior to dispensing to the patient [see Dosage and Administration ( 2.4 )] . 2.3 Recommended Dosage in Pediatric Patients Prevention of CMV Disease in Pediatric Kidney Transplant Patients : For pediatric kidney transplant patients 4 months to 16 years of age, the recommended once daily mg dose (7 x BSA x CrCl) should start within 10 days of post-transplantation until 200 days post-transplantation. Prevention of CMV Disease in Pediatric Heart Transplant Patients : For pediatric heart transplant patients 1 month to 16 years of age, the recommended once daily mg dose (7 x BSA x CrCl) should start within 10 days of transplantation until 100 days post-transplantation. The recommended once daily dosage of valganciclovir for oral solution is based on body surface area (BSA) and creatinine clearance (CrCl) derived from a modified Schwartz formula, and is calculated using the equation below: Pediatric Dose (mg) = 7 x BSA x CrCl (calculated using a modified Schwartz formula). If the calculated Schwartz creatinine clearance exceeds 150 mL/min/1.73m 2 , then a maximum value of 150 mL/min/1.73m 2 should be used in the equation. The k values used in the modified Schwartz formula are based on pediatric patient age, as shown in Table 1. Table 1 k Values According to Pediatric Patient Age* k value Pediatric Patient Age 0.33 Infants less than 1 year of age with low birth weight for gestational age 0.45 Infants less than 1 year of age with birth weight appropriate for gestational age 0.45 Children aged 1 to less than 2 years 0.55 Boys aged 2 to less than 13 years Girls aged 2 to less than 16 years 0.7 Boys aged 13 to 16 years *The k values provided are based on the Jaffe method of measuring serum creatinine, and may require correction when enzymatic methods are used 1 . Monitor serum creatinine levels regularly and consider changes in height and body weight and adapt the dose as appropriate during prophylaxis period. All calculated doses should be rounded to the nearest 10 mg increment for the actual deliverable dose. The oral dispenser is graduated in 0.2 mL increments. A 50 mg dose is equivalent to 1 mL. If the calculated dose exceeds 900 mg, a maximum dose of 900 mg should be administered. Valganciclovir for oral solution is the preferred formulation since it provides the ability to administer a dose calculated according to the formula above. modified Schwartz formula 2.4 Preparation of Valganciclovir for Oral Solution Wearing disposable gloves is recommended during reconstitution and when wiping the outer surface of the bottle/cap and the table after reconstitution. Prior to dispensing to the patient, valganciclovir for oral solution must be prepared by the pharmacist as follows [see How Supplied/Storage and Handling ( 16 )] : Measure 91 mL of purified water in a graduated cylinder. Shake the valganciclovir bottle to loosen the powder. Remove the child resistant bottle cap and add approximately half the total amount of water for constitution to the bottle and shake the closed bottle well for about 1 minute. Add the remainder of water and shake the closed bottle well for about 1 minute. This prepared solution contains 50 mg of valganciclovir free base per 1 mL. Remove the child resistant bottle cap and push the bottle adapter into the neck of the bottle. Close bottle with child resistant bottle cap tightly. This will assure the proper seating of the bottle adapter in the bottle and child resistant status of the cap. Store constituted oral solution under refrigeration at 2°C to 8°C (36°F to 46°F) for no longer than 49 days. Do not freeze. Write the discard date of the constituted oral solution on the bottle label. The patient package insert, which includes the dosing instructions for patients, and 2 oral dispensers should be dispensed to the patient [see Patient Counseling Information ( 17 )] . 2.6 Handling and Disposal Caution should be exercised in the handling of valganciclovir for oral solution. Because valganciclovir is considered a potential teratogen and carcinogen in humans, caution should be observed in handling,

6 ADVERSE REACTIONS The following serious adverse reactions are discussed in greater detail in other sections of the labeling: Hematologic Toxicity [see Warnings and Precautions ( 5.1 ) ]. Acute Renal Failure [see Warnings and Precautions ( 5.2 ) ]. Impairment of Fertility [see Warnings and Precautions ( 5.3 )] . Fetal Toxicity [see Warnings and Precautions ( 5.4 )] . Mutagenesis and Carcinogenesis [see Warnings and Precautions ( 5.5 )] . The most common adverse reactions and laboratory abnormalities reported in at least one indication by greater than or equal to 20% of adult patients treated with valganciclovir tablets are diarrhea, pyrexia, fatigue, nausea, tremor, neutropenia, anemia, leukopenia, thrombocytopenia, headache, insomnia, urinary tract infection, and vomiting. The most common reported adverse reactions and laboratory abnormalities reported in greater than or equal to 20% of pediatric solid organ transplant recipients treated with valganciclovir for oral solution or tablets are diarrhea, pyrexia, upper respiratory tract infection, urinary tract infection, vomiting, neutropenia, leukopenia, and headache. Adult patients: Most common adverse reactions and laboratory abnormalities (reported in at least one indication by greater than or equal to 20% of patients) are diarrhea, pyrexia, fatigue, nausea, tremor, neutropenia, anemia, leukopenia, thrombocytopenia, headache, insomnia, urinary tract infection, and vomiting. ( 6.1 ) Pediatric patients: Most common adverse reactions and laboratory abnormalities (reported in greater than or equal to 20% of pediatric solid organ transplant recipients) are diarrhea, pyrexia, upper respiratory tract infection, urinary tract infection, vomiting, neutropenia, leukopenia, and headache. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact contact AvKARE at 1-855-361-3993 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience 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 rates observed in practice. Valganciclovir, a prodrug of ganciclovir, is rapidly converted to ganciclovir after oral administration. Adverse reactions known to be associated with ganciclovir usage can therefore be expected to occur with valganciclovir. Adverse Reactions in Adults: Treatment of CMV Retinitis in AIDS Patients : In a clinical study for the treatment of CMV retinitis in HIV-infected patients, the adverse reactions reported by patients receiving valganciclovir tablets (n=79) or intravenous ganciclovir (n=79) for 28 days of randomized therapy (21 days induction dose and 7 days maintenance dose), respectively, included diarrhea (16%, 10%), nausea (8%, 14%), and headache (9%, 5%). The incidence of adverse reactions was similar between the group who received valganciclovir tablets and the group who received intravenous ganciclovir. The frequencies of neutropenia (ANC less than 500/μL) were 11% for patients receiving valganciclovir tablets compared with 13% for patients receiving intravenous ganciclovir. Anemia (Hgb less than 8 g/dL) occurred in 8% of patients in each group. Other laboratory abnormalities occurred with similar frequencies in the two groups. Adverse reactions and laboratory abnormalities are available for 370 patients who received maintenance therapy with valganciclovir tablets 900 mg once daily in two open-label clinical trials. Approximately 252 (68%) of these patients received valganciclovir tablets for more than nine months (maximum duration was 36 months). Table 3 and Table 4 show pooled selected adverse reactions and abnormal laboratory values from these patients. Table 3 Pooled Selected Adverse Reactions Reported in greater than or equal to 5% of Patients who Received Valganciclovir Tablets Maintenance Therapy for CMV Retinitis Patients with CMV Retinitis Adverse Reactions according to Body System Valganciclovir Tablets (N=370) % Gastrointestinal system Diarrhea 41 Nausea 30 Vomiting 21 Abdominal pain 15 General disorders and administrative site conditions Pyrexia 31 Nervous system disorders Headache 22 Insomnia 16 Neuropathy peripheral 9 Paresthesia 8 Eye disorders Retinal detachment 15 Table 4 Pooled Selected Laboratory Abnormalities Reported in Patients Who Received Valganciclovir Tablets Maintenance Therapy for the Treatment of CMV Retinitis Patients with CMV Retinitis Laboratory Abnormalities Valganciclovir Tablets (N=370) % Neutropenia: ANC/µL < 500 19 500 to < 750 17 750 to < 1000 17 Anemia: Hemoglobin g/dL < 6.5 7 6.5 to < 8.0 13 8.0 to < 9.5 16 Thrombocytopenia: Platelets/µL < 25000 4 25000 to < 50000 6 50000 to < 100000 22 Serum Creatinine: mg/dL > 2.5 3 > 1.5 to 2.5 12 Prevention of CMV Disease in Solid Organ Transplant Patients: Table 5 shows selected adverse reactions regardless of severity with an incidence of greater than or equal to 5% from a

7 DRUG INTERACTIONS In vivo drug-drug interaction studies were not conducted with valganciclovir. However, because valganciclovir is rapidly and extensively converted to ganciclovir, drug-drug interactions associated with ganciclovir will be expected for valganciclovir. Drug-drug interaction studies with ganciclovir were conducted in patients with normal renal function. Following concomitant administration of valganciclovir and other renally excreted drugs, patients with impaired renal function may have increased concentrations of ganciclovir and the coadministered drug. Therefore, these patients should be closely monitored for toxicity of ganciclovir and the coadministered drug. Established and other potentially significant drug interactions conducted with ganciclovir are listed in Table 9. Table 9 Established and Other Potentially Significant Drug Interactions with Ganciclovir Name of the Concomit a nt Drug Change in the Concentration of Ganciclovir or Concomitant Drug Clinical Comment Imipenem-cilastatin Unknown Coadministration with imipenem­ cilastatin is not recommended because generalized seizures have been reported in patients who received ganciclovir and imipenem-cilastatin. Cyclosporine or amphotericin B Unknown Monitor renal function when valganciclovir is coadministered with cyclosporine or amphotericin B because of potential increase in serum creatinine [see Warnings and Precautions (5.2)]. Mycophenolate mofetil (MMF) ↔ Ganciclovir (in patients with normal renal function) ↔ MMF (in patients with normal renal function) Based on increased risk, patients should be monitored for hematological and renal toxicity. Other drugs associated with myelosuppression or nephrotoxicity (e.g., adriamycin, dapsone, doxorubicin, flucytosine, hydroxyurea, pentamidine, tacrolimus, trimethoprim/ sulfamethoxazole, vinblastine, vincristine, and zidovudine) Unknown Because of potential for higher toxicity, coadministration with valganciclovir should be considered only if the potential benefits are judged to outweigh the risks. Didanosine ↔ Ganciclovir ↑ Didanosine Patients should be closely monitored for didanosine toxicity (e.g., pancreatitis) Probenecid ↑ Ganciclovir Valganciclovir dose may need to be reduced. Monitor for evidence of ganciclovir toxicity. Imipenem-cilastatin: Seizures were reported in patients receiving ganciclovir and imipenem-cilastatin. Concomitant use is not recommended unless the potential benefits outweigh the risks. ( 7 ) Cyclosporine or amphotericin B: When coadministered with valganciclovir, the risk of nephrotoxicity may be increased. Monitor renal function. ( 5.2, 7 ) Mycophenolate mofetil (MMF): When coadministered with valganciclovir, the risk of hematological and renal toxicity may be increased. Monitor for ganciclovir and MMF toxicity. ( 7 ) Other drugs associated with myelosuppression or nephrotoxicity: Due to potential for increased toxicity, consider for concomitant use with valganciclovir only if the potential benefits are judged to outweigh the risks. ( 7 ) Didanosine: Ganciclovir coadministered with didanosine may increase didanosine levels. Monitor for didanosine toxicity (e.g., pancreatitis). ( 7 ) Probenecid: May increase ganciclovir levels. Monitor for evidence of ganciclovir toxicity. ( 7 )