Valacyclovir Hydrochloride (Page 2 of 10)

2.4 Patients with Renal Impairment

Dosage recommendations for adult patients with reduced renal function are provided in Table 1 [see Use in Specific Populations (8.5, 8.6), Clinical Pharmacology (12.3)]. Data are not available for the use of valacyclovir tablets in pediatric patients with a creatinine clearance less than 50 mL/min/1.73 m².

Table 1. Valacyclovir Tablets Dosage Recommendations for Adults with Renal Impairment

Indications	Normal Dosage Regimen (Creatinine Clearance ≥50 mL/min)	Creatinine Clearance (mL/min)
		30 to 49	10 to 29	<10
Cold sores (Herpes Labialis) Do not exceed 1 day of treatment.	Two 2-gram doses taken 12 hours apart	Two 1-gram doses taken 12 hours apart	Two 500-mg doses taken 12 hours apart	500-mg single dose
Genital herpes: Initial episode	1 gram every 12 hours	no reduction	1 gram every 24 hours	500 mg every 24 hours
Genital herpes: Recurrent episode	500 mg every 12 hours	no reduction	500 mg every 24 hours	500 mg every 24 hours
Genital herpes: Suppressive therapy
Immunocompetent patients	1 gram every 24 hours	no reduction	500 mg every 24 hours	500 mg every 24 hours
Alternate dose for immunocompetent patients with less than or equal to 9 recurrences/year	500 mg every 24 hours	no reduction	500 mg every 48 hours	500 mg every 48 hours
HIV-1˗infected patients	500 mg every 12 hours	no reduction	500 mg every 24 hours	500 mg every 24 hours
Herpes zoster	1 gram every 8 hours	1 gram every 12 hours	1 gram every 24 hours	500 mg every 24 hours

Hemodialysis

Patients requiring hemodialysis should receive the recommended dose of valacyclovir tablets after hemodialysis. During hemodialysis, the half-life of acyclovir after administration of valacyclovir tablets is approximately 4 hours. About one-third of acyclovir in the body is removed by dialysis during a 4-hour hemodialysis session.

Peritoneal Dialysis

There is no information specific to administration of valacyclovir tablets in patients receiving peritoneal dialysis. The effect of chronic ambulatory peritoneal dialysis (CAPD) and continuous arteriovenous hemofiltration/dialysis (CAVHD) on acyclovir pharmacokinetics has been studied. The removal of acyclovir after CAPD and CAVHD is less pronounced than with hemodialysis, and the pharmacokinetic parameters closely resemble those observed in patients with end-stage renal disease (ESRD) not receiving hemodialysis. Therefore, supplemental doses of valacyclovir tablets should not be required following CAPD or CAVHD.

3 DOSAGE FORMS AND STRENGTHS

Valacyclovir tablets, equivalent to 500 mg of valacyclovir base, are blue, capsule-shaped, coated tablets debossed “SZ” on one side and 393 on the other side.

Valacyclovir tablets, equivalent to 1 gm of valacyclovir base, are blue, capsule-shaped, coated tablets debossed “SZ” on one side and 394 on other side with partial score bar on both sides

4 CONTRAINDICATIONS

Valacyclovir tablets are contraindicated in patients who have had a demonstrated clinically significant hypersensitivity reaction (e.g., anaphylaxis) to valacyclovir, acyclovir, or any component of the formulation [see Adverse Reactions (6.3)].

5 WARNINGS AND PRECAUTIONS

5.1 Thrombotic Thrombocytopenic Purpura/Hemolytic Uremic Syndrome (TTP/HUS)

TTP/HUS, in some cases resulting in death, has occurred in patients with advanced HIV-1 disease and also in allogeneic bone marrow transplant and renal transplant recipients participating in clinical trials of valacyclovir hydrochloride at doses of 8 grams per day. Treatment with valacyclovir hydrochloride should be stopped immediately if clinical signs, symptoms, and laboratory abnormalities consistent with TTP/HUS occur.

5.2 Acute Renal Failure

Cases of acute renal failure have been reported in:

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Elderly patients with or without reduced renal function. Caution should be exercised when administering valacyclovir hydrochloride to geriatric patients, and dosage reduction is recommended for those with impaired renal function [see Dosage and Administration (2.4), Use in Specific Populations (8.5)].

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Patients with underlying renal disease who received higher-than-recommended doses of valacyclovir hydrochloride for their level of renal function. Dosage reduction is recommended when administering valacyclovir hydrochloride to patients with renal impairment [see Dosage and Administration (2.4), Use in Specific Populations (8.6)].

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Patients receiving other nephrotoxic drugs. Caution should be exercised when administering valacyclovir hydrochloride to patients receiving potentially nephrotoxic drugs.

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Patients without adequate hydration. Precipitation of acyclovir in renal tubules may occur when the solubility (2.5 mg/mL) is exceeded in the intratubular fluid. Adequate hydration should be maintained for all patients.

In the event of acute renal failure and anuria, the patient may benefit from hemodialysis until renal function is restored [see Dosage and Administration (2.4), Adverse Reactions (6.3)].