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Valacyclovir and acyclovir pharmacokinetics in immunocompromised children.
Pediatr Blood Cancer. 2008 Jun 16;
Bomgaars L, Thompson P, Berg S, Serabe B, Aleksic A, Blaney S
BACKGROUND: Valacyclovir, an orally administered pro-drug of acyclovir, is utilized in the therapy of herpes simplex and herpes zoster infections. Little data regarding the pharmacokinetics, safety and tolerability are available for pediatric patients. This report describes acyclovir pharmacokinetics following valacyclovir administration in immunocompromised pediatric patients, compares pharmacokinetic parameters following oral valacyclovir and IV acyclovir, and provides a limited assessment of efficacy in the setting of active herpes zoster infection. PROCEDURE: A total of 37 immunocompromised children were enrolled on one of two studies. Pharmacokinetic data are available for 32 patients following valacyclovir (15 mg/kg) administration, 11 of whom also had pharmacokinetic sampling following IV acyclovir administration. Three patients received valacyclovir as treatment for herpes zoster infections. RESULTS: Mean (+/-SD) C(max) values for acyclovir following oral valacyclovir were 18.8 +/- 7 microM with a total exposure of 4,106 +/- 1,519 microM min. The mean bioavailability of acyclovir from valacyclovir was 64%. Grade 1 nausea and emesis, which occurred in five patients was the only valacyclovir-related toxicity. Two of the three patients treated for herpes zoster had complete scabbing of lesions by day 9. CONCLUSION: Valacyclovir (15 mg/kg) was well tolerated in pediatric patients and demonstrated excellent bioavailability. Consideration should be given to the use of oral valacyclovir for the treatment of herpes zoster in clinically stable pediatric oncology patients. Pediatr Blood Cancer (c) 2008 Wiley-Liss, Inc.
The treatment of herpes simplex infections: an evidence-based review.
Arch Intern Med. 2008 Jun 9; 168(11): 1137-44
Cernik C, Gallina K, Brodell RT
Genital and labial herpes simplex virus infections are frequently encountered by primary care physicians in the United States. Whereas the diagnosis of this condition is often straightforward, choosing an appropriate drug (eg, acyclovir, valacyclovir hydrochloride, or famciclovir) and dosing regimen can be confusing in view of (1) competing clinical approaches to therapy; (2) evolving dosing schedules based on new research; (3) approved regimens of the Food and Drug Administration that may not match recommendations of the Centers for Disease Control and Prevention or of other experts; and (4) dissimilar regimens for oral and genital infections. The physician must first choose an approach to treatment (ie, intermittent episodic therapy, intermittent suppressive therapy, or chronic suppressive therapy) based on defined clinical characteristics and patient preference. Then, an evidence-based dosing regimen must be selected. In this review, data from all sources are tabulated to provide a handy clinical reference.
MMWR Recomm Rep. 2008 Jun 6; 57(RR-5): 1-30; quiz CE2-4
Harpaz R, Ortega-Sanchez IR, Seward JF,
These recommendations represent the first statement by the Advisory Committee on Immunization Practices (ACIP) on the use of a live attenuated vaccine for the prevention of herpes zoster (zoster) (i.e., shingles) and its sequelae, which was licensed by the U.S. Food and Drug Administration (FDA) on May 25, 2006. This report summarizes the epidemiology of zoster and its sequelae, describes the zoster vaccine, and provides recommendations for its use among adults aged > or =60 years in the United States. Zoster is a localized, generally painful cutaneous eruption that occurs most frequently among older adults and immunocompromised persons. It is caused by reactivation of latent varicella zoster virus (VZV) decades after initial VZV infection is established. Approximately one in three persons will develop zoster during their lifetime, resulting in an estimated 1 million episodes in the United States annually. A common complication of zoster is postherpetic neuralgia (PHN), a chronic, often debilitating pain condition that can last months or even years. The risk for PHN in patients with zoster is 10%-18%. Another complication of zoster is eye involvement, which occurs in 10%-25% of zoster episodes and can result in prolonged or permanent pain, facial scarring, and loss of vision. Approximately 3% of patients with zoster are hospitalized; many of these episodes involved persons with one or more immunocompromising conditions. Deaths attributable to zoster are uncommon among persons who are not immunocompromised. Prompt treatment with the oral antiviral agents acyclovir, valacyclovir, and famciclovir decreases the severity and duration of acute pain from zoster. Additional pain control can be achieved in certain patients by supplementing antiviral agents with corticosteroids and with analgesics. Established PHN can be managed in certain patients with analgesics, tricyclic antidepressants, and other agents. Licensed zoster vaccine is a lyophilized preparation of a live, attenuated strain of VZV, the same strain used in the varicella vaccines. However, its minimum potency is at least 14-times the potency of single-antigen varicella vaccine. In a large clinical trial, zoster vaccine was partially efficacious at preventing zoster. It also was partially efficacious at reducing the severity and duration of pain and at preventing PHN among those developing zoster. Zoster vaccine is recommended for all persons aged > or =60 years who have no contraindications, including persons who report a previous episode of zoster or who have chronic medical conditions. The vaccine should be offered at the patient's first clinical encounter with his or her health-care provider. It is administered as a single 0.65 mL dose subcutaneously in the deltoid region of the arm. A booster dose is not licensed for the vaccine. Zoster vaccination is not indicated to treat acute zoster, to prevent persons with acute zoster from developing PHN, or to treat ongoing PHN. Before administration of zoster vaccine, patients do not need to be asked about their history of varicella (chickenpox) or to have serologic testing conducted to determine varicella immunity.
Ophthalmology. 2008 Jun; 115(6): 1104-5; author reply 1105-6
Kim SJ, Lo WR
Steroid and antiviral treatment for Bell's palsy.
Lancet. 2008 May 31; 371(9627): 1818-20
Hato N, Murakami S, Gyo K
Sex Transm Dis. 2008 May 5;
Fife KH, Warren TJ, Justus SE, Heitman CK,
BACKGROUND:: Antiviral suppressive therapy of genital herpes is often initiated based on the established pattern of recurrences in an individual. Because most persons with first episode herpes simplex virus type 2 (HSV-2) infection experience recurrences and because viral shedding occurs frequently in the first year after infection, we examined the strategy of initiating suppressive therapy shortly after diagnosis of genital HSV-2 infection. SUBJECTS AND METHODS:: From June 16, 2004 to July 26, 2006, 384 subjects from 74 sites in the United States, Canada, Argentina, Brazil, and Chile who were newly diagnosed with a first recognized episode of genital herpes at the time of the screening visit or within 3 months before the screening visit were randomized (2:1) to receive valacyclovir 1 g once daily or placebo for 24 weeks. Subjects were instructed to return to clinic during suspected genital herpes outbreaks for clinician confirmation of recurrences. RESULTS:: Valacyclovir significantly prolonged the time to first recurrence of HSV-2 genital herpes in newly diagnosed subjects compared with placebo, with approximately 43% of subjects on placebo and 71% of subjects on valacyclovir recurrence-free at 24 weeks (P
Br J Clin Pharmacol. 2008 May 5;
Zhang Y, Jiang XH, Hu YQ, Li ZR, Su L, Wang ZG, Ma G
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * The absorption of valacyclovir presents a highly negative correlation with the level of P-glycoprotein expression. * It has been confirmed that a polymorphism of the MDR1 gene in exon 26 is related to the level of P-glycoprotein expression in intestine. * This study was conducted to find the relationship between polymorphism of MDR1 gene and absorption of valacyclovir. WHAT THIS STUDY ADDS * Linkage disequilibrium exists between G2677T/A in exon 21 and C3435T in exon 26, between C1236T in exon 12 and C3435T, but not between C1236T and G2677T/A of MDR1 gene in the Chinese Han ethnic population. * Three single nucleotide polymorphisms of MDR1 gene do not influence the absorption of valacyclovir in the healthy Chinese Han ethnic population. AIMS To investigate the influence of three single nucleotide polymorphisms (SNPs) in exon 12 (C1236T), exon 21 (G2677T/A) and exon 26 (C3435T) of MDR1 gene on the absorption of valacyclovir after a single oral administration in the Chinese Han ethnic population. METHODS Two hundred healthy Chinese subjects were genotyped for the SNPs of C1236T, G2677T/A and C3435T in the MDR1 gene using allele-specific polymerase chain reaction. Linkage disequilibrium (LD) was analysed. Twenty-four subjects derived from a large random sample (n = 200) received a single oral dose of 600 mg valacyclovir. Plasma concentrations of acyclovir were determined up to 14 h after administration to obtain a pharmacokinetic profile. RESULTS LD existed between G2677T/A in exon 21 and C3435T in exon 26 (P < 0.001), between C1236T in exon 12 and C3435T (P < 0.001), but not between C1236T and G2677T/A (P > 0.05). C(max), AUC(0-1.5 h) and AUC(0-infinity) were used as indices of valacyclovir absorption. AUC(0-infinity) for the 2677TA genotype was 17.45 +/- 2.40 microg x h/ml, which was much higher compared with the 2677GG, GA and TT genotypes of 10.44 +/- 1.00, 11.84 +/- 2.83, 11.34 +/- 2.32 microg x h/ml, respectively (P < 0.05). Similarly, a statistically significant difference of AUC(0-infinity) was also observed for different linked genotypes at position 2677 vs. 3435, and 1236 vs. 3435 (P < 0.05). However, there was no significant difference in valacyclovir absorptive pharmacokinetics between carriers and noncarriers of different haplotypes (P > 0.05). CONCLUSIONS Three SNPs of MDR1 gene did not influence the absorption of a single oral dose of 600 mg valacyclovir in healthy Chinese Han ethnic subjects.
Genital herpes: gynaecological aspects.
J Obstet Gynaecol Can. 2008 Apr; 30(4): 347-61
Money D, Steben M, Wong T, Gruslin A, Yudin M, Cohen H, Boucher M, Mackinnon C, Paquet C, van Schalkwyk J
OBJECTIVE: The purpose of this guideline is to provide recommendations to gynaecology health care providers on optimal management of genital herpes. OUTCOMES: More effective prevention of complications and transmission of genital herpes. EVIDENCE: Medline was searched for articles published in French and English related to genital herpes and gynaecology. Additional articles were identified through the references of these articles. All study types and recommendation reports were reviewed. RECOMMENDATIONS: 1. Up to 70% of all genital HSV-2 infections are transmitted during asymptomatic shedding; therefore, the use of condoms is recommended to lessen the likelihood of disease transmission. (II-A) 2. A laboratory-based diagnosis of genital herpes is essential for its effective management. (II-A) 3. Suppressive treatment is suggested for patients who have * at least 6 recurrences per year * significant complications, but fewer than 6 recurrences per year * their quality of life significantly affected * social and sexual dysfunction * to lower the risk of transmission to a sexual partner or fetus/neonate. (II-B) 4. The use of the anti-viral valacyclovir, coupled with condoms and safer sex counselling, is recommended for individuals with proven genital herpes. (I-B) 5. Routine or targeted HSV screening is not indicated.
J Infect Dis. 2008 May 1; 197(9): 1289-95
Arora A, Mendoza N, Brantley J, Yates B, Dix L, Tyring S
A dosage of 1 g of valacyclovir 3 times per day (TID) for 7 days has already been shown to be superior to an oral dosage of 800 mg acyclovir 5 times per day for 7 days in immunocompetent individuals. The objective of this study was to assess the safety and efficacy of an oral dosage of valacyclovir, 1 g TID versus 2 g TID, for the treatment of herpes zoster in immunocompromised patients > or =18 years of age. The oral dosage schedule of 2 g of valacyclovir TID reaches acyclovir plasma levels similar to those achieved with intravenous acyclovir therapy given to immunocompromised patients (10 mg/kg every 8 h for 7 days). In this double-blind study, 87 immunocompromised patients with clinical evidence of localized herpes zoster were randomized to receive oral valacyclovir therapy for 7 days, either 1 g TID or 2 g TID, within 72 h after onset of zoster rash. Patients were seen and assessed for cutaneous healing, zoster-associated pain (ZAP), and/or zoster-associated abnormal sensations (ZAAS), up to 24 weeks. Participants in both arms of the study demonstrated similar median times to full crusting of the rash (8 days), and both dosages were safe and effective therapies for reduction of ZAP and ZAAS in the immunocompromised patient population.
[Herpes simplex virus latency, reactivation, and a new antiviral therapy for herpetic keratitis]
Nippon Ganka Gakkai Zasshi. 2008 Mar; 112(3): 247-64; discussion 265
Shimomura Y
Although many factors that trigger the herpes simplex virus (HSV) reactivation from latency have been reported, how HSV resides in a latent state in the normal human cornea still needs to be defined. We therefore conducted a series of studies regarding various aspects of HSV infections. To understand how patients subjectively perceived changes in their daily life that could have induced HSV reactivation, we first performed a comprehensive survey on the subjective factors in patients who had experienced recurrent herpetic keratitis. The result of our survey revealed that stress, lack of sleep, shoulder stiffness, and physical fatigue were the key factors. There were various causes for stress, and stress associated with reactivation often occurred between spring and summer. Regarding HSV latency in the normal cornea, we used real-time polymerase chain reaction (PCR) to determine the presence of HSV in the donor and host corneas. The findings showed that on average, those host corneas with a history of HSV keratitis had 1.6 x 10(4) copies/mg of HSV DNA, while the host corneas without a history and the donor corneas had 8.7 and 4.9 x 10(2) copies/mg of HSV DNA, respectively. Based on these observations, it is reasonable to infer that latent viruses could have resided in a normal cornea without a history and were transmitted to a host cornea through corneal transplantation. We also quantified the virus load in tears before and after ocular surgery (one week after corneal transplantation or the next day after vitreous surgery). Our results indicated that both the detection rate and the average copy number of HSV DNA had a tendency to increase postperatively. Moreover, we tried to differentiate the HSV strains that were involved in the recurrent lesions. In only one of the studied cases, could we find a single different nucleotide between two HSV strains. It seemed possible that two different strains of HSV had set off the same episode of reactivation. In recent years, chemokines have become known for their action in mediating inflammatory diseases. We suspected that chemokines might also play a role in the antiviral mechanism and examined the chemokine-derived antiviral activity. We used eight chemokines, including RANTES/CCL5, MIP-lalpha/ CCL3, and MIP-1beta/CCL4, in a murine HSK model with Vero cells. These chemokines directly bound to HSV and the chemokine-bound HSV was later resisted by the neutralizing antibody of envelope protein gB. Furthermore, by electron microscope analysis, it became clear that these chemokines had cut an opening in the HSV envelope. Consequently, these chemokines had significantly inhibited the HSV infection on Vero cells. In addition, the virus load in tears was decreased and the corneal opacity was less severe. We concluded in that study that during early infection, chemokines accumulated in the corneal stroma have the ability to protect cells and tissues from HSV infection. As for antiviral therapy, acyclovir (ACV) eye ointment has been effective for patients with herpetic keratitis. However, patients often find it difficult to successfully follow the treatment due to the required frequent application and the blurred vision after application. On the other hand, valaciclovir (VCV), which is the oral prodrug of ACV, has become commercially available in recent years for treating nonocular herpetic diseases. We therefore examined and compared the efficacies of oral VCV, oral ACV, ACV eye ointment, and ACV eye drops in a murine keratitis model; the group treated with oral VCV did show a significantly good antiviral effect. We have proved that oral VCV can be a beneficial alternative antiviral therapy for patients with difficulty in complying with the ACV eye ointment treatment.