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Details

Stereochemistry ABSOLUTE
Molecular Formula C13H20N6O4.ClH.H2O
Molecular Weight 378.812
Optical Activity UNSPECIFIED
Defined Stereocenters 1 / 1
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of VALACYCLOVIR HYDROCHLORIDE MONOHYDRATE

SMILES

O.Cl.CC(C)[C@H](N)C(=O)OCCOCN1C=NC2=C1N=C(N)NC2=O

InChI

InChIKey=KNOVZDRKHSHEQN-JZGIKJSDSA-N
InChI=1S/C13H20N6O4.ClH.H2O/c1-7(2)8(14)12(21)23-4-3-22-6-19-5-16-9-10(19)17-13(15)18-11(9)20;;/h5,7-8H,3-4,6,14H2,1-2H3,(H3,15,17,18,20);1H;1H2/t8-;;/m0../s1

HIDE SMILES / InChI

Molecular Formula C13H20N6O4
Molecular Weight 324.3357
Charge 0
Count
Stereochemistry ABSOLUTE
Additional Stereochemistry No
Defined Stereocenters 1 / 1
E/Z Centers 0
Optical Activity UNSPECIFIED

Molecular Formula H2O
Molecular Weight 18.0153
Charge 0
Count
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Molecular Formula ClH
Molecular Weight 36.461
Charge 0
Count
Stereochemistry ACHIRAL
Additional Stereochemistry No
Defined Stereocenters 0 / 0
E/Z Centers 0
Optical Activity NONE

Acyclovir is a synthetic antiviral nucleoside analogue. A screening program for antiviral drugs begun at Burroughs Wellcome in the 1960s resulted in the discovery of acyclovir in 1974. Preclinical investigation brought the drug to clinical trials in 1977 and the first form of the drug (topical) was available to physicians in 1982. Activity of acyclovir is greatest against herpes 1 and herpes 2, less against varicella zoster, still less against Epstein-Barr, and very little against cytomegalovirus. Acyclovir is an antiviral agent only after it is phosphorylated in infected cells by a viral-induced thymidine kinase. Acyclovir monophosphate is phosphorylated to diphosphate and triphosphate forms by cellular enzymes in the infected host cell where the drug is concentrated. Acyclovir triphosphate inactivates viral deoxyribonucleic acid polymerase.

CNS Activity

Curator's Comment: Valacyclovir hydrochloride is rapidly converted to acyclovir which was detected in CSF after oral administration of valacyclovir.

Approval Year

TargetsConditions

Conditions

ConditionModalityTargetsHighest PhaseProduct
Primary
ZOVIRAX

Approved Use

Oral ZOVIRAX® (acyclovir) is indicated for the treatment: Herpes Zoster Infections: ZOVIRAX is indicated for the acute treatment of herpes zoster (shingles). Genital Herpes: ZOVIRAX is indicated for the treatment of initial episodes and the management of recurrent episodes of genital herpes. Chickenpox: ZOVIRAX is indicated for the treatment of chickenpox (varicella). Injectable ZOVIRAX® (acyclovir) is indicated for the treatment: Herpes Simplex Infections in Immunocompromised Patients: ZOVIRAX 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: ZOVIRAX for Injection is indicated for the treatment of severe initial clinical episodes of herpes genitalis in immunocompetent patients. Herpes Simplex Encephalitis: ZOVIRAX for Injection is indicated for the treatment of herpessimplex encephalitis. Neonatal Herpes Simplex Virus Infection: ZOVIRAX for Injection is indicated for the treatmentof neonatal herpes infections. Varicella-Zoster Infections in Immunocompromised Patients: ZOVIRAX for Injection is indicated for the treatment of varicella-zoster (shingles) infections in immunocompromised patients.

Launch Date

1982
Primary
ZOVIRAX

Approved Use

Oral ZOVIRAX® (acyclovir) is indicated for the treatment: Herpes Zoster Infections: ZOVIRAX is indicated for the acute treatment of herpes zoster (shingles). Genital Herpes: ZOVIRAX is indicated for the treatment of initial episodes and the management of recurrent episodes of genital herpes. Chickenpox: ZOVIRAX is indicated for the treatment of chickenpox (varicella). Injectable ZOVIRAX® (acyclovir) is indicated for the treatment: Herpes Simplex Infections in Immunocompromised Patients: ZOVIRAX 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: ZOVIRAX for Injection is indicated for the treatment of severe initial clinical episodes of herpes genitalis in immunocompetent patients. Herpes Simplex Encephalitis: ZOVIRAX for Injection is indicated for the treatment of herpessimplex encephalitis. Neonatal Herpes Simplex Virus Infection: ZOVIRAX for Injection is indicated for the treatmentof neonatal herpes infections. Varicella-Zoster Infections in Immunocompromised Patients: ZOVIRAX for Injection is indicated for the treatment of varicella-zoster (shingles) infections in immunocompromised patients.

Launch Date

1982
Primary
VALTREX

Approved Use

INDICATIONS AND USAGE. VALTREX is a nucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients Cold Sores (Herpes Labialis), Genital Herpes, Treatment in immunocompetent patients (initial or recurrent episode), Suppression in immunocompetent or HIV-infected patients, Reduction of transmission, Herpes Zoster. Pediatric Patients Cold Sores (Herpes Labialis), Chickenpox Limitations of Use. The efficacy and safety of VALTREX have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-infected patients.

Launch Date

2004
Primary
VALTREX

Approved Use

INDICATIONS AND USAGE. VALTREX is a nucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients Cold Sores (Herpes Labialis), Genital Herpes, Treatment in immunocompetent patients (initial or recurrent episode), Suppression in immunocompetent or HIV-infected patients, Reduction of transmission, Herpes Zoster. Pediatric Patients Cold Sores (Herpes Labialis), Chickenpox Limitations of Use. The efficacy and safety of VALTREX have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-infected patients.

Launch Date

2004
Primary
VALTRE

Approved Use

INDICATIONS AND USAGE. VALTREX is a nucleoside analogue DNA polymerase inhibitor indicated for: Adult Patients Cold Sores (Herpes Labialis), Genital Herpes, Treatment in immunocompetent patients (initial or recurrent episode), Suppression in immunocompetent or HIV-infected patients, Reduction of transmission, Herpes Zoster. Pediatric Patients Cold Sores (Herpes Labialis), Chickenpox Limitations of Use. The efficacy and safety of VALTREX have not been established in immunocompromised patients other than for the suppression of genital herpes in HIV-infected patients.

Launch Date

2004
Cmax

Cmax

ValueDoseCo-administeredAnalytePopulation
599.2 ng/mL
400 mg single, oral
dose: 400 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
ACYCLOVIR plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
AUC

AUC

ValueDoseCo-administeredAnalytePopulation
3015.7 ng × h/mL
400 mg single, oral
dose: 400 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
ACYCLOVIR plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
T1/2

T1/2

ValueDoseCo-administeredAnalytePopulation
3.9 h
400 mg single, oral
dose: 400 mg
route of administration: Oral
experiment type: SINGLE
co-administered:
ACYCLOVIR plasma
Homo sapiens
population: HEALTHY
age: ADULT
sex: FEMALE / MALE
food status: FASTED
Funbound

Funbound

ValueDoseCo-administeredAnalytePopulation
79%
ACYCLOVIR plasma
Homo sapiens
population: UNKNOWN
age: UNKNOWN
sex: UNKNOWN
food status: UNKNOWN
Overview

Overview

CYP3A4CYP2C9CYP2D6hERG
Drug as perpetrator​Drug as victim
PubMed

PubMed

TitleDatePubMed
Selective activity of various antiviral compounds against HHV-7 infection.
1999 Aug
[Cerebral and renal toxicity of acyclovir in a patient treated for meningoencephalitis].
1999 Nov
Antiviral activity of ganciclovir elaidic acid ester against herpesviruses.
2000 Mar
Thienothiadiazine 2,2-dioxide acyclonucleosides: synthesis and antiviral activity.
2000 May
Cough syncope with herpetic tracheobronchitis.
2001 Apr
Heart transplantation and the Batista operation for children with refractory heart failure.
2001 Apr
Acyclovir treatment in 2 patients with benign trigeminal sensory neuropathy.
2001 Apr
Prophylaxis of intravenous immunoglobulin and acyclovir in perinatal varicella.
2001 Feb
Anti-herpesvirus activity of (1'S,2'R)-9-[[1',2'-bis(hydroxymethyl)-cycloprop-1'-yl]methyl] x guanine (A-5021) in vitro and in vivo.
2001 Feb
Persistent verrucous varicella as the initial manifestation of HIV infection.
2001 Feb
Epstein-Barr virus-related lymphoproliferative disease complicating childhood acute lymphoblastic leukemia: no recurrence after unrelated donor bone marrow transplantation.
2001 Jan
Herpetic folliculitis and syringitis simulating acne excoriée.
2001 Jan
Management of the neonate whose mother received suppressive acyclovir therapy during late pregnancy.
2001 Jan
Susceptibility to acyclovir of herpes simplex virus isolates obtained between 1977 and 1996 in Japan.
2001 Jan
Virological, clinical, and ophthalmologic features of cytomegalovirus retinitis after hematopoietic stem cell transplantation.
2001 Jan 15
A pilot study of treatment of herpes labialis with 1072 nm narrow waveband light.
2001 Mar
Predictors of recurrent herpes simplex virus keratitis. Herpetic Eye Disease Study Group.
2001 Mar
Predictive modeling and heterogeneity of baseline risk in meta-analysis of individual patient data.
2001 Mar
[Intrauterine herpes simplex virus infection].
2001 Mar-Apr
Acyclovir prophylaxis in late pregnancy prevents recurrent genital herpes and viral shedding.
2001 May
Contact dermatitis from topical antiviral drugs.
2001 May
FV-100 versus valacyclovir for the prevention of post-herpetic neuralgia and the treatment of acute herpes zoster-associated pain: A randomized-controlled trial.
2017 Jul
Diagnosis and Treatment of Acute Retinal Necrosis: A Report by the American Academy of Ophthalmology.
2017 Mar
Patents

Sample Use Guides

Valacyclovir may be given without regard to meals. Cold Sores (Herpes Labialis): The recommended dosage of Valacyclovir for treatment of cold sores is 2 grams twice daily for 1 day taken 12 hours apart. Therapy should be initiated at the earliest symptom of a cold sore. Genital Herpes: Initial Episode: The recommended dosage of Valacyclovir for treatment of initial genital herpes is 1 gram twice daily for 10 days. Therapy was most effective when administered within 48 hours of the onset of signs and symptoms. Recurrent Episodes: The recommended dosage of Valacyclovir for treatment of recurrent genital herpes is 500 mg twice daily for 3 days. Initiate treatment at the first sign or symptom of an episode.
Route of Administration: Oral
In uptake studies using valacyclovir, the extraction solution (water/methanol, 50:50) was added to the Caco-2 cells after the uptake period. After standing for 1 h at room temperature, the solutions were centrifuged and the supernatants were filtered. The filtrate was analyzed by highperformance liquid chromatography (HPLC). Valacyclovir showed a marked inhibitory effect (K=440 +/- 29mkM) on [14C]glycylsarcosine uptake via the apical PEPT1.
Substance Class Chemical
Created
by admin
on Mon Mar 31 21:58:56 GMT 2025
Edited
by admin
on Mon Mar 31 21:58:56 GMT 2025
Record UNII
JF64RVR4E3
Record Status Validated (UNII)
Record Version
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Name Type Language
VALACICLOVIR (AS HYDROCHLORIDE MONOHYDRATE)
Preferred Name English
VALACYCLOVIR HYDROCHLORIDE MONOHYDRATE
Common Name English
VALACICLOVIR HYDROCHLORIDE MONOHYDRATE
Common Name English
L-VALINE, 2-((2-AMINO-1,6-DIHYDRO-6-OXO-9H-PURIN-9-YL)METHOXY)ETHYL ESTER, HYDROCHLORIDE, HYDRATE (1:1:1)
Systematic Name English
VALACICLOVIR HYDROCHLORIDE HYDRATE
Common Name English
Valaciclovir hydrochloride hydrate [WHO-DD]
Common Name English
VALACICLOVIR HYDROCHLORIDE HYDRATE [JAN]
Common Name English
VALACICLOVIR HYDROCHLORIDE HYDRATE [EP MONOGRAPH]
Common Name English
Code System Code Type Description
CAS
1218948-84-5
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
NON-SPECIFIC STOICHIOMETRY
EVMPD
SUB37499
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
FDA UNII
JF64RVR4E3
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
PUBCHEM
135428922
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
CAS
521915-75-3
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
EVMPD
SUB126884
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
DAILYMED
JF64RVR4E3
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
RXCUI
2604686
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
SMS_ID
100000129151
Created by admin on Mon Mar 31 21:58:56 GMT 2025 , Edited by admin on Mon Mar 31 21:58:56 GMT 2025
PRIMARY
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