Progress in meeting today's demands in genital herpes: an overview of current management

Interventions for men and women with their first episode of genital herpes

BACKGROUND

Genital herpes is incurable, and is caused by the herpes simplex virus (HSV). First-episode genital herpes is the first clinical presentation of herpes that a person experiences. Current treatment is based around viral suppression in order to decrease the length and severity of the episode.

OBJECTIVES

To determine the effectiveness and safety of the different existing treatments for first-episode genital herpes on the duration of symptoms and time to recurrence.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (from inception to April 2016), MEDLINE (from inception to April 2016), the Specialised Register of the Cochrane Sexually Transmitted Infections Review Group (from inception to April 2016), EMBASE (from inception to April 2016), PsycINFO (from inception to April 2016), CINAHL (from inception to April 2016), LILACS (from inception to April 2016), AMED (from inception to April 2016), and the Alternative Medicines Specialised Register (from inception to April 2016). We handsearched a number of relevant journals, searched reference lists of all included studies, databases of ongoing trials, and other Internet databases.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) on participants with first-episode genital herpes. We excluded vaccination trials, and trials in which the primary objective assessed a complication of HSV infection.

DATA COLLECTION AND ANALYSIS

All studies written in English were independently assessed by at least two review authors for inclusion, risk of bias for each trial, and to extract data. Studies requiring translation were assessed for inclusion, trial quality, and data extraction by external translators.

MAIN RESULTS

We included 26 trials with 2084 participants analysed. Most of the studies were conducted in the United Kingdom (UK) and United States (US), and involved men and women experiencing their first episode of genital herpes, with the exception of three studies which included only women. We rated the majority of these studies as having an unclear risk of bias; largely due to lack of information supplied in the publications, and due to the age of the trials. This review found low quality evidence from two studies of oral acyclovir, when compared to placebo, reduced the duration of symptoms in individuals undergoing their first episode of genital herpes (mean difference (MD) -3.22, 95% confidence interval (CI) -5.91 to -0.54; I(2) = 52%). In two studies (112 participants), intravenous acyclovir decreased the median number of days that patients with first-episode herpes suffered symptoms. Oral valaciclovir (converted to acyclovir) also showed a similar length of symptom duration when compared to acyclovir in two studies.There is currently no evidence that topical acyclovir reduces symptoms (MD -0.61 days, 95% CI -2.16 to 0.95; 3 RCTs, 195 participants, I(2) statistic = 56%). There is also no current evidence that the topical treatments of cicloxolone cream, carbenoxolone sodium cream, adenosine arabinoside, idoxuridine in dimethyl sulfoxide, when compared to placebo reduced the duration of symptoms in people undergoing their first episode of herpes.Two studies reported no evidence of a reduction in the number of median days to recurrence following treatment with oral acyclovir versus placebo. Adverse events were generally poorly reported by all of the included studies and we were unable to quantitatively analyse this outcome. For those taking acyclovir, there were no serious adverse events; the most common adverse events reported for oral acyclovir were coryza, dizziness, tiredness, diarrhoea and renal colic. For intravenous acyclovir these were phlebitis, nausea and abnormal liver function tests and for topical acyclovir there was pain with the topical application.Those undergoing interferon treatment had significantly more adverse events compared to those taking placebo.

AUTHORS' CONCLUSIONS

There is low quality evidence from this review that oral acyclovir reduced the duration of symptoms for genital herpes. However, there is low quality evidence which did not show that topical antivirals reduced symptom duration for patients undergoing their first episode of genital herpes. This review was limited by the inclusion of skewed data, resulting in few trials that we were able to meta-analyse.

CMX001 potentiates the efficacy of acyclovir in herpes simplex virus infections

Although acyclovir (ACV) has proven to be of value in the therapy of certain herpes simplex virus (HSV) infections, there is a need for more effective therapies, particularly for serious infections in neonates and immunocompromised individuals, where resistance to this drug can be problematic. CMX001 is an orally bioavailable lipid conjugate of cidofovir that is substantially less nephrotoxic than the parent drug and has excellent antiviral activity against all the human herpesviruses. This compound retains full antiviral activity against ACV-resistant laboratory and clinical isolates. The combined efficacy of CMX001 and ACV was evaluated in a new real-time PCR combination assay, which demonstrated that the combination synergistically inhibited the replication of HSV in cell culture. This was also confirmed in murine models of HSV infection, where the combined therapy with these two drugs synergistically reduced mortality. These results suggest that CMX001 may be effective in the treatment of ACV-resistant HSV infections and as an adjunct therapy in individuals with suboptimal responses to ACV.

Oligonucleotides and polyribonucleotides: a review of antiviral activity

Current antiviral therapies are insufficient for treating emerging, re-emerging and established viral diseases. In an effort to find new therapeutics, oligo- and polyribonucleotides are being studied for their antiviral capabilities. Studies have shown that uniquely modified single- and double-stranded nucleic acid constructs are effective in inhibiting viral proliferation by various mechanisms. This review gives a brief history and highlights the development of oligo- and polyribonucleotides as antiviral agents primarily in the fields of interferon induction, mRNA complementation and reverse transcriptase inhibition.

Simultaneous detection of herpes simplex virus types 1 and 2 by real-time PCR and Pyrosequencing

BACKGROUND

Up to 80% of the US adult population has been exposed to herpes simplex virus (HSV) type 1, primarily during childhood. Also, approximately 20% of the US population has contracted genital herpes from HSV-2 infections. Clinical symptoms can present as fever, headache, malaise, myalgia, and cold sores/lesions that cause pain, itching, dysuria, and vaginal or urethral discharge. A recurrence of infection is common. HSV culturing is characterized by low sensitivity with variable success rates due to shipping conditions.

OBJECTIVE

To design and validate a real-time PCR assay capable of simultaneously detecting each HSV subtype.

STUDY DESIGN

ATCC-purchased HSV-1 and HSV-2 positive samples and HSV-1 and HSV-2 infected clinical specimens were assayed simultaneously with shared amplification primers and subtype-specific probes against the HSV glycoprotein B gene on a Rotor-Gene 3000 platform. Separately, two PCR reactions were performed in which one primer contained a 5' biotin modification. Single-stranded DNA from the amplicon was purified and Pyrosequenced.

RESULTS

The quantitative range of the assay extended from 10(8) through 10(0) copies of each virus (r(2) > 0.991) and specificity was determined by non-amplification of 37 different human pathogens, including other herpesviruses such as VZV, CMV, and EBV. Sensitivity and specificity values of 100% were calculated by concordance analysis between the real-time PCR and the DNA Pyrosequencing results (HSV-1: n = 119, HSV-2: n = 120). Application of this assay to 4581 cervical swab specimens collected from women visiting physicians primarily in six states provided detection rates of 3.1% for HSV-1 and 7.6% for HSV-2. The average age of women infected with HSV-1 was 29.5 versus 35.6 for HSV-2.

CONCLUSIONS

This procedure was demonstrated as both highly sensitive and specific for the detection of HSV-1 and HSV-2 in a single reaction. Also, the integration of Pyrosequencing analysis permitted an innovative and rapid verification for each subtype.

Efficacy and Safety of Valacyclovir for the Suppression and Episodic Treatment of Herpes Simplex Virus in Patients with HIV

Three randomized controlled trials of valacyclovir for the management of recurrences of genital herpes in HIV-infected persons were conducted between 1991 and 2002. One study evaluated episodic therapy for the treatment of genital herpes, and 2 studies evaluated continuous suppressive therapy. Valacyclovir at 1000 mg twice daily for 5 days was comparable to acyclovir at 200 mg 5 times daily in accelerating healing of a single episode of genital herpes (hazard ratio, 1.0; 95% confidence interval [CI], 0.8-1.2; P=.89). Valacyclovir at 500 mg twice daily was effective in preventing or delaying recurrences of genital herpes compared with placebo (hazard ratio, 0.20; 95% CI, 0.13-0.30; P<.001) and with valacyclovir at 1000 mg once daily (hazard ratio, 0.56; 95% CI, 0.40-0.80; P=.001), in 6-month and 48-week studies, respectively. The safety profile of valacyclovir was similar to that of acyclovir. Valacyclovir is well tolerated, safe, and effective for the treatment and suppression of recurrent genital herpes in human immunodeficiency virus-infected persons.

Treatment of herpes simplex virus infections

Herpes simplex virus (HSV) types 1 and 2 are ubiquitous organisms that cause infections in human populations throughout the world. The clinical manifestations of HSV infections are varied, ranging from asymptomatic disease to life-threatening illness in neonates and immunocompromised hosts. This article will review the common presentations for HSV disease and the current recommendations for the treatment of these infections. A detailed summary of the antiviral drugs used to treat HSV infections is also presented.

Clinical manifestations and treatment considerations of herpes simplex virus infection

Herpes simplex viruses (HSV) types 1 and 2 cause infections manifesting as dermatologic, immunologic, and neurologic disorders. Some of the most important manifestations and complications of HSV infection are considered here in a neuroanatomic context. This discussion should aid in understanding the pathogenesis and, in some cases, diagnosis and management of associated HSV-related diseases. The sensory nervous system, rather than skin and mucous membranes, is the primary target of HSV infection. With the intention of extending the benefits of acyclovir, valacyclovir is now being explored in a number of HSV-related conditions. This review extends contemporary thinking about how new antiherpetic drugs might be put to greater therapeutic use in the future.