Prophylactic valacyclovir in a patient with recurrent vestibular disturbances secondary to vestibular neuritis

A 57-year-old woman with herpes labialis and previously diagnosed with vestibular neuritis experienced recurrences of vertigo and disequilibrium. Initially preceded by oral herpes outbreaks or upper respiratory infections, these recurrences became spontaneous and more frequent. Vestibular function demonstrated a 25% decrease in energy function in the right and the patient had left beating nystagmus on positional maneuver. Her reoccurrences of vestibular disturbances were followed up. Concurrently, she was prescribed daily valacyclovir (500 mg, 1 per day) given for the prevention of herpes labialis outbreaks by her primary care physician. Recurrences of disequilibrium stopped completely as well as oral herpes outbreaks.

Effects of valacyclovir on markers of disease progression in postpartum women co-infected with HIV-1 and herpes simplex virus-2

Objective

Herpes simplex virus type 2 (HSV-2) suppression has been shown to reduce HIV-1 disease progression in non-pregnant women and men, but effects on pregnant and postpartum women have not been described.

Methods

We analyzed data from a cohort of Kenyan women participating in a randomized clinical trial of HSV-2 suppression. Pregnant HIV-1-seropositive, HSV-2-seropositive women who were not eligible for antiretroviral therapy (WHO stage 1–2, CD4>250 cells/µl) were randomized to either 500 mg valacyclovir or placebo twice daily from 34 weeks gestation through 12 months postpartum. Women received zidovudine and single-dose nevirapine for prevention of mother-to-child HIV-1 transmission. HIV-1 progression markers, including CD4 count and plasma HIV-1 RNA levels, were measured serially. Multivariate linear regression was used to compare progression markers between study arms.

Results

Of 148 women randomized, 136 (92%) completed 12 months of postpartum follow-up. While adjusted mean CD4 count at 12 months (565 cells/µl placebo arm, 638 cells/µl valacyclovir arm) increased from antenatal levels in both arms, the mean CD4 count increase was 73 cells/µl higher in the valacyclovir arm than placebo arm (p = 0.03). Mean increase in CD4 count was 154 cells/µl in the valacyclovir arm, almost double the increase of 78 cells/µl in the placebo arm. At 12 months, adjusted HIV-1 RNA levels in the placebo arm increased by 0.66 log₁₀ copies/ml from baseline, and increased by only 0.21 log₁₀ copies/ml in the valacyclovir arm (0.40 log₁₀ copies/ml difference, p = 0.001).

Conclusion

Women randomized to valacyclovir suppressive therapy during pregnancy and postpartum had greater increases in CD4 counts and smaller increases in plasma HIV-1 RNA levels than women in the placebo arm. Valacyclovir suppression during pregnancy and breastfeeding may improve outcomes and delay antiretroviral therapy for HIV-1/HSV-2 co-infected women.

The antiviral drug valacyclovir successfully suppresses salivary gland hypertrophy virus (SGHV) in laboratory colonies of Glossina pallidipes

Many species of tsetse flies are infected with a virus that causes salivary gland hypertrophy (SGH) symptoms associated with a reduced fecundity and fertility. A high prevalence of SGH has been correlated with the collapse of two laboratory colonies of Glossina pallidipes and colony maintenance problems in a mass rearing facility in Ethiopia. Mass-production of G. pallidipes is crucial for programs of tsetse control including the sterile insect technique (SIT), and therefore requires a management strategy for this virus. Based on the homology of DNA polymerase between salivary gland hypertrophy virus and herpes viruses at the amino acid level, two antiviral drugs, valacyclovir and acyclovir, classically used against herpes viruses were selected and tested for their toxicity on tsetse flies and their impact on virus replication. While long term per os administration of acyclovir resulted in a significant reduction of productivity of the colonies, no negative effect was observed in colonies fed with valacyclovir-treated blood. Furthermore, treatment of a tsetse colony with valacyclovir for 83 weeks resulted in a significant reduction of viral loads and consequently suppression of SGH symptoms. The combination of initial selection of SGHV-negative flies by non-destructive PCR, a clean feeding system, and valacyclovir treatment resulted in a colony that was free of SGH syndromes in 33 weeks. This is the first report of the use of a drug to control a viral infection in an insect and of the demonstration that valacyclovir can be used to suppress SGH in colonies of G. pallidipes.

Clinical burden of herpes simplex virus disease in people with human immunodeficiency virus

BACKGROUND

Serologic studies indicate that herpes simplex virus (HSV)-1 and HSV-2 infections are highly prevalent among people infected with HIV. As an ulcerative genital disease, HSV may be important to HIV transmission and HIV-comorbidity. Routine clinical care of HSV in this population has not been described.

METHODS

Data were abstracted from medical records of HIV-infected individuals by the Adult/Adolescent Spectrum of HIV Disease Project. Clinician-documented HSV diagnosis and HSV treatment, defined as any prescription for acyclovir, valacyclovir, or famciclovir, were the outcomes of interest. We present descriptive statistics and trends in HSV diagnosis and treatment.

RESULTS

Between 1989 and 2004, 61,299 people were followed in this study. HSV was diagnosed in 20% of the population, and 32% of the population received HSV antiviral prescriptions. Prescriptions for episodic treatment were given to 28% of patients, and 11% received prescriptions for suppressive therapy. The average annual rate of HSV diagnosis declined by 31% during the course of the study.

CONCLUSIONS

Clinically recognized HSV infections were frequent despite declining rates of diagnosis. Providers should have a high index of suspicion for HSV and consider routine screening and suppressive therapy for patients at risk of clinical disease.

Infant safety during and after maternal valacyclovir therapy in conjunction with antiretroviral HIV-1 prophylaxis in a randomized clinical trial

BACKGROUND

Maternal administration of the acyclovir prodrug valacyclovir is compatible with pregnancy and breastfeeding. However, the safety profile of prolonged infant and maternal exposure to acyclovir in the context of antiretrovirals (ARVs) for prevention of mother-to-child HIV-1 transmission (PMTCT) has not been described.

METHODS

Pregnant Kenyan women co-infected with HIV-1/HSV-2 with CD4 counts > 250 cells/mm(3) were enrolled at 34 weeks gestation and randomized to twice daily 500 mg valacyclovir or placebo until 12 months postpartum. Women received zidovudine from 28 weeks gestation and single dose nevirapine was given to women and infants at the time of delivery for PMTCT. Infant blood was collected at 6 weeks for creatinine and ALT. Breast milk specimens were collected at 2 weeks postpartum from 71 women in the valacyclovir arm; acyclovir levels were determined for a random sample of 44 (62%) specimens. Fisher's Exact and Wilcoxon rank-sum tests were used for analysis.

RESULTS

One hundred forty-eight women were randomized and 146 mother-infant pairs were followed postpartum. PMTCT ARVs were administered to 98% of infants and all mothers. Valacyclovir was not associated with infant or maternal toxicities or adverse events, and no congenital malformations were observed. Infant creatinine levels were all normal (< 0.83 mg/dl) and median creatinine (median 0.50 mg/dl) and infant growth did not differ between study arms. Acyclovir was detected in 35 (80%) of 44 breast milk samples collected at 2 weeks postpartum. Median and maximum acyclovir levels were 2.62 and 10.15 mg/ml, respectively (interquartile range 0.6-4.19).

CONCLUSIONS

Exposure to PMTCT ARVs and acyclovir after maternal administration of valacyclovir during pregnancy and postpartum to women co-infected with HIV-1/HSV-2 was not associated with an increase in infant or maternal toxicities or adverse events.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00530777.

Standard-dose and high-dose daily antiviral therapy for short episodes of genital HSV-2 reactivation: three randomised, open-label, cross-over trials

BACKGROUND

Skin and mucosal herpes simplex virus type 2 (HSV-2) shedding predominantly occurs in short subclinical episodes. We assessed whether standard-dose or high-dose antiviral therapy reduces the frequency of such shedding.

METHODS

HSV-2-seropositive, HIV-seronegative people were enrolled at the University of Washington Virology Research Clinic (WA, USA). We did three separate but complementary open-label cross-over studies comparing no medication with aciclovir 400 mg twice daily (standard-dose aciclovir), valaciclovir 500 mg daily (standard-dose valaciclovir) with aciclovir 800 mg three times daily (high-dose aciclovir), and standard-dose valaciclovir with valaciclovir 1 g three times daily (high-dose valaciclovir). The allocation sequence was generated by a random number generator. Study drugs were supplied in identical, numbered, sealed boxes. Study periods lasted 4-7 weeks, separated by 1 week wash-out. Participants collected genital swabs four times daily for quantitative HSV DNA PCR. Clinical data were masked from laboratory personnel. The primary endpoint was within-person comparison of shedding rate in each study group. Analysis was per protocol. The trials are registered at ClinicalTrials.gov (NCT00362297, NCT00723229, NCT01346475).

RESULTS

Of 113 participants randomised, 90 were eligible for analysis of the primary endpoint. Participants collected 23 605 swabs; 1272 (5·4%) were HSV-positive. The frequency of HSV shedding was significantly higher in the no medication group (n=384, 18·1% of swabs) than in the standard-dose aciclovir group (25, 1·2%; incidence rate ratio [IRR] 0·05, 95% CI 0·03-0·08). High-dose aciclovir was associated with less shedding than standard-dose valaciclovir (198 [4·2%] vs 209 [4·5%]; IRR 0·79, 95% CI 0·63-1·00). Shedding was less frequent in the high-dose valaciclovir group than in the standard-dose valaciclovir group (164 [3·3%] vs 292 [5·8%]; 0·54, 0·44-0·66). The number of episodes per person-year did not differ significantly for standard-dose valaciclovir (22·6) versus high-dose aciclovir (20·2; p=0·54), and standard-dose valaciclovir (14·9) versus high-dose valaciclovir (16·5; p=0·34), but did for no medication (28·7) and standard-dose aciclovir (10·0; p=0·001). Median episode duration was longer for no medication than for standard-dose aciclovir (13 h vs 7 h; p=0·01) and for standard-dose valaciclovir than for high-dose valaciclovir (10 h vs 7 h; p=0·03), but did not differ significantly between standard-dose valaciclovir and high-dose aciclovir (8 h vs 8 h; p=0·23). Likewise, maximum log(10) copies of HSV detected per mL was higher for no medication than for standard dose aciclovir (3·3 vs 2·9; p=0·02), and for standard-dose valaciclovir than for high-dose valaciclovir (2·5 vs 3·0; p=0·001), but no significant difference was recorded for standard-dose valaciclovir versus high-dose aciclovir (2·7 vs 2·8; p=0·66). 80% of episodes were subclinical in all study groups. Except for a higher frequency of headaches with high-dose valaciclovir (n=13, 30%) than with other regimens, all regimens were well tolerated.

INTERPRETATION

Short bursts of subclinical genital HSV reactivation are frequent, even during high-dose antiherpes therapy, and probably account for continued transmission of HSV during suppressive antiviral therapy. More potent antiviral therapy is needed to eliminate HSV transmission.

FUNDING

NIH. Valaciclovir was provided for trial 3 for free by GlaxoSmithKline.

[Enzymatic activity of thymidine kinase of herpes simlex virus strain resistant to H-phosphonates of Acv]

Cloned laboratory mutants of herpes simplex virus type I resistant to acycloguanosine H-phosphonate have been investigated. For all clones were shown that mutations resulted to increasing of sensitivity to acting of sidofovir. Thymidine kinase of mutant viruses partially preserves the ability to phosphorilate thymidine, but loses the ability to phosphorilate BVDU.

Valacyclovir suppressive therapy reduces plasma and breast milk HIV-1 RNA levels during pregnancy and postpartum: a randomized trial

BACKGROUND

The effect of herpes simplex virus type 2 (HSV-2) suppression on human immunodeficiency virus type 1 (HIV-1) RNA in the context of prevention of mother-to-child transmission (PMTCT) interventions is unknown.

METHODS

Between April 2008 and August 2010, we conducted a randomized, double-blind trial of twice daily 500 mg valacyclovir or placebo beginning at 34 weeks gestation in 148 HIV-1/HSV-2 coinfected pregnant Kenyan women ineligible for highly active antiretroviral therapy (CD4 > 250 cells/mm(3)). Women received zidovudine and single dose nevirapine for PMTCT and were followed until 12 months postpartum.

RESULTS

Mean baseline plasma HIV-1 RNA was 3.88 log(10) copies/mL. Mean plasma HIV-1 was lower during pregnancy (-.56 log(10) copies/mL; 95% confidence interval [CI], -.77 to -.34) and after 6 weeks postpartum (-.51 log(10) copies/mL; 95% CI, -.73 to -.30) in the valacyclovir arm than the placebo arm. Valacyclovir reduced breast milk HIV-1 RNA detection at 6 and 14 weeks postpartum compared with placebo (30% lower, P = .04; 46% lower, P = .01, respectively), but not after 14 weeks. Cervical HIV-1 RNA detection was similar between arms (P = .91).

CONCLUSIONS

Valacyclovir significantly decreased early breast milk and plasma HIV-1 RNA among women receiving PMTCT.

CLINICAL TRIALS REGISTRATION

NCT00530777.

Current management and recommendations for access to antiviral therapy of herpes labialis

Herpes labialis is a common skin infective condition, worldwide, which is primarily caused by HSV-1. Recurrent episodes of herpes labialis, also known as cold sores, can be frequent, painful, long-lasting and disfiguring for infected patients. At present, there are two types of antivirals for the treatment of herpes labialis, topical and oral, which are available over the counter or as prescription-only. The aim of antiviral therapy is to block viral replication to enable shortening the duration of symptoms and to accelerate healing of the lesions associated with herpes labialis. This review examines the evidence for the effectiveness of current topical and oral antivirals in the management of recurrent episodes of herpes labialis. In most countries, oral antivirals for herpes labialis are available as prescription-only. However, in early 2010, the oral antiviral famciclovir was reclassified from prescription-only medicine to pharmacist-controlled status in New Zealand. The benefits and risks associated with moving an antiviral therapy for herpes labialis from prescription-only to pharmacist-controlled status are reviewed here, and the implications for patients, general physicians and pharmacists are considered.

Synthesis of 1,4-disubstituted mono and bis-triazolocarbo-acyclonucleoside analogues of 9-(4-hydroxybutyl)guanine by Cu(I)-catalyzed click azide-alkyne cycloaddition

A series of novel mono-1,2,3-triazole and bis-1,2,3-triazole acyclonucleoside analogues of 9-(4-hydroxybutyl)guanine was prepared via copper(I)-catalyzed 1,3-dipolar cycloaddition of N-9 propargylpurine, N-1-propargylpyrimidines/as-triazine with the azido-pseudo-sugar 4-azidobutylacetate under solvent-free microwave conditions, followed by treatment with K(2)CO(3)/MeOH, or NH(3)/MeOH. All compounds studied in this work were screened for their antiviral activities [against human rhinovirus (HRV) and hepatitis C virus (HCV)] and antibacterial activities against a series of Gram positive and negative bacteria.

Topical tacrolimus induced extensive varicella zoster infection

Tacrolimus ointment 0.1 percent is a well-established topical therapy for treating atopic dermatitis. Efficacy and safety have been described in several trials. Here, we present a patient with rapid onset of extensive varicella zoster infection in tacrolimus-treated skin: a side effect that has only occasionally been reported. Early recognition is important because rapid treatment for herpes zoster may lead to less frequent post-herpetic neuralgia and serious complications.

Multispectroscopic studies of the interaction of calf thymus DNA with the anti-viral drug, valacyclovir

The present study investigated the binding interaction between an antiviral drug, valacyclovir and calf thymus DNA (CT-DNA) using emission, absorption, circular dichroism, viscosity and DNA melting studies. In fluorimetric studies, thermodynamic enhancement constant (K(D)) and bimolecular enhancement constant (K(B)) were calculated at different temperatures and demonstrated that fluorescence enhancement is not initiated by a dynamic process, but instead by a static process that involves complex DNA formation in the ground state. Further, the enthalpy and entropy of the reaction between the drug and CT-DNA showed that the reaction is exothermic and enthalpy-favored. In addition, detectable changes in the circular dichroism spectrum of CT-DNA in the presence of valacyclovir indicated conformational changes in the DNA double helix following interaction with the drug. All these results prove that this antiviral drug interacts with CT-DNA via an intercalative mode of binding.

Antiviral drugs for viruses other than human immunodeficiency virus

Most viral diseases, with the exception of those caused by human immunodeficiency virus, are self-limited illnesses that do not require specific antiviral therapy. The currently available antiviral drugs target 3 main groups of viruses: herpes, hepatitis, and influenza viruses. With the exception of the antisense molecule fomivirsen, all antiherpes drugs inhibit viral replication by serving as competitive substrates for viral DNA polymerase. Drugs for the treatment of influenza inhibit the ion channel M(2) protein or the enzyme neuraminidase. Combination therapy with Interferon-α and ribavirin remains the backbone treatment for chronic hepatitis C; the addition of serine protease inhibitors improves the treatment outcome of patients infected with hepatitis C virus genotype 1. Chronic hepatitis B can be treated with interferon or a combination of nucleos(t)ide analogues. Notably, almost all the nucleos(t) ide analogues for the treatment of chronic hepatitis B possess anti-human immunodeficiency virus properties, and they inhibit replication of hepatitis B virus by serving as competitive substrates for its DNA polymerase. Some antiviral drugs possess multiple potential clinical applications, such as ribavirin for the treatment of chronic hepatitis C and respiratory syncytial virus and cidofovir for the treatment of cytomegalovirus and other DNA viruses. Drug resistance is an emerging threat to the clinical utility of antiviral drugs. The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir. Widespread antiviral resistance has limited the clinical utility of M(2) inhibitors for the prevention and treatment of influenza infections. This article provides an overview of clinically available antiviral drugs for the primary care physician, with a special focus on pharmacology, clinical uses, and adverse effects.

Adjuvant therapy for laryngeal papillomatosis

Respiratory papillomatosis affects the larynx in most cases. It is a relatively rare disease, with potentially devastating consequences for the patient. Many studies have proven the viral etiology of the disease. Surgery is the most successful mode of treatment. Adjuvant therapy is used in cases of aggressive disease. The most successful adjuvant drugs are interferon, various virostatics (e.g., acyclovir, valacyclovir, and cidofovir) and indole-3-carbinol. Vaccination with a quadrivalent vaccine against HPV will probably decrease the incidence of respiratory papillomatosis or help in the treatment of the disease in the future. The results of adjuvant therapy of laryngeal papillomatosis at the University Department of ORL & HNS in Ljubljana are comparable to the results in other centers around the world.