PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Valacyclovir”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources

The Albion Street Centre database, Sydney, Australia.

The Albion Street Centre was established in 1985 as an HIV testing and early management center. More than 22,000 people have been screened for HIV and other blood-borne infections at the Centre, and approximately 3,600 people with HIV/AIDS have been managed there. Approximately 1,600 patients with various stages of HIV disease are currently managed at the Centre by a staff of 60 health care professionals and about 1,000 volunteers. The Albion Street Centre's computer database began recording selected demographic, epidemiologic, clinical, and laboratory characteristics when the first patient presented in 1985. Since then, the complexity and utilization of the database has increased in parallel with improvement in the understanding of the natural history and pathogenesis of HIV infection. Over 100 peer-reviewed publications and presentations have been produced from the database and 45 clinical trials have used the database to identify potential subjects. All data are de-identified and are protected by multiple password codes. Approximately 700 variables are collected from each HIV-positive patient at the initial visit to the Centre and up to 200 variables are added at each subsequent routine clinic visit. The variables collected include the following: standard epidemiologic characteristics; transmission and behavioral parameters, clinical signs and symptoms; laboratory test results; treatments; nutritional history; body composition parameters; psychological assessment results; and management history, including neuropsychological testing. The overall number and characteristics of patients recorded in the database are reported monthly, and are used to plan services, for prevention and educational programs, and as an indicator of the effectiveness of campaigns to encourage HIV-positive people to attend clinics for early management. When these patients have been identified they are invited to participate in the study. Individual patient records are identified and accessed if they meet certain criteria for flagging. For example, patients who have lost more than 5% of their maximal weight are flagged and referred to the dietician for assessment. Further uses for the database are to identify cohorts of patients who are seroconverters and to follow their natural history-the Centre has over 250 patients for whom a documented HIV-positive test has been obtained within 12 months of a documented HIV-negative test; to investigate clinical observations that have been associated with particular drug therapy, e.g., investigation of the reported association between the use of valacyclovir and the thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS)-like complex showed patients with terminal-stage AIDS demonstrated this syndrome independently of their therapy and probably as a consequence of multiorgan failure; and to document the relationship between nutritional intervention and survival, for which use of the database enabled an historical cohort that matched the cases under investigation to be selected. In conclusion, the database is a dynamic and integral part of the assessment, management, and research program of the Albion Street Centre, where it is used by all professional staff.

Adolescent↗

Varicella-zoster virus.

Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization.

Acyclovir↗

Treatment of acyclovir-resistant herpetic ulceration with topical foscarnet and antiviral sensitivity analysis.

BACKGROUND: Herpes simplex virus (HSV) can produce persistent mucocutaneous disease in patients with the acquired immunodeficiency syndrome (AIDS). In this case report, we evaluate the efficacy, safety and viral resistance after topical foscarnet in severe genital ulceration due to acyclovir-resistant HSV-2. CASE REPORT: A 45-year-old African woman was known for an HIV infection with severe immunosuppression (CD4 <100/mm3). She had received a long-term prophylaxis with acyclovir (400 mg b.i.d.) for a recurrent genital herpes. Few weeks after stopping this prophylaxis, she developed large genital ulcerations progressing despite valacyclovir treatment (1,000 mg t.i.d.). Cultures were positive for HSV-2, resistance to acyclovir was shown by the plaque reduction assay and topical foscarnet was tried. Treatment consisted of a 20-min application of topical foscarnet 2.4% twice a day. Dramatic improvement was observed with rapid antalgia, and cicatrization of the genital ulcerations was observed after 50 days. HSV could not be detected on the mucosal surface. Initially, HSV-2 was resistant to acyclovir but sensitive to foscarnet. After 1 month of topical treatment, HSV-2 became sensitive to acyclovir and was still sensitive to foscarnet. Finally, after 6 weeks of treatment, no virus could be detected by culture. CONCLUSION: Topical foscarnet (2.4%) is a convenient treatment for chronic genital herpes. Resistance to acyclovir disappears few weeks after stopping this drug and sensitivity to foscarnet persists during the 50 days of treatment.

Acyclovir↗

Antiinfectives update: focus on treatment and prevention of viral and associated infections.

OBJECTIVE: To review the clinically significant antiinfectives approved by the Food and Drug Administration (FDA) since 1996, with an emphasis on agents used for treatment, prevention, or suppression of infection in immunocompromised individuals. DATA SOURCES: A MEDLINE search covering November 1994 to March 1998 was conducted to identify all antiinfectives (new medications and old medications with new indications) and the pertinent literature for review. The search was updated in August 1998 and supplemented with an FDA listing of approved drugs to enhance completeness. STUDY SELECTION: Clinically relevant studies were selected to highlight specific points about each medication. Preclinical publications were used when sufficient information was not available from clinical trials and this information was needed for clinical practice. CONCLUSIONS: Several new and promising antiretroviral agents (stavudine, lamivudine, saquinavir soft-gel capsules, nelfinavir, efavirenz) have been approved, which may allow more options to control HIV viremia. New options for treatment, prevention, and suppression of infections in immunocompromised individuals include azithromycin, cidofovir, famciclovir, valacyclovir, and itraconazole suspension. Liposomal-based amphotericin products may be associated with less toxicity than conventional amphotericin B; however, superior efficacy has not been proven.

AIDS-Related Opportunistic Infections↗

Several options for antiviral treatment trials in multiple sclerosis--but which targets should be selected?

Involvement of viruses in the pathogenesis of multiple sclerosis (MS) is a long-lived hypothesis, which is has not yet been proven nor refuted. This is partly due to difficulties in the evaluation of diagnostic findings on persistent infections by common viruses such as herpesviruses and endogenous retroviruses. Progress in antiviral treatment of central nervous system (CNS) herpesvirus infections has stimulated controlled trials of long-term therapy with acyclovir and valacyclovir in MS, but conclusive results are not yet available. Other treatment possibilities might include anti-retroviral therapy, as well as attempts to counteract the effects of viruses in triggering attacks of MS following upper respiratory tract infections. Before such trials are initiated, however, further diagnostic evidence of the involvement of target viruses seems warranted.

Antiviral Agents↗

Recent advances in varicella-zoster virus infection.

Varicella-zoster virus has developed a complex strategy that allows it to remain latent in the body and avoid destruction by the immune system. Although varicella and zoster have been recognized since antiquity, several new clinical syndromes--including chronic chickenpox with persistent verrucous lesions and disseminated varicella without skin lesions--have been noted in patients with AIDS. Acyclovir has been the mainstay for treating severe varicella-zoster virus infections; however, newer antiviral agents, including valacyclovir and famciclovir, have expanded therapeutic options for treating adults with herpes zoster. The recently licensed live attenuated vaccine for varicella-zoster virus is effective in preventing chickenpox, and the vaccine's ability to stimulate immunity in seropositive adults suggests a promising strategy with which to modify the course of herpes zoster.

Adult↗

[Clinical manifestations of the subfamily alpha-herpesvirinae in childhood].

Herpes simplex virus(HSV) and varicella-zoster virus(VZV) belonging to the subfamily of alpha-herpesvirinae have the capacity to establish latent infection in neural tissues and to reactivate from these sites. HSV infection is characterized by a vesicular eruption, fever, and other constitutional symptoms but frequently inapparent both in primary and recurrent infections. However, the infection produces a wide spectrum of illness ranging from the trivial fever blisters to the most severe fatal sporadic encephalitis and neonatal infection. In contrast, VZV develops varicella, a common contagious disease of childhood during primary infection and zoster by reactivation of latent virus acquired during varicella. In normal children, the systemic symptoms of both diseases are mild, whereas serious complications are often observed in children with deficiencies in cell-mediated immunity. Acyclovir has been the drug of choice for treatment of severe infection with HSV and VZV for approximately 2 decades. Now, two new agents, valacyclovir and famciclovir will supplant acyclovir for certain indications.

Alphaherpesvirinae↗

Management of herpes zoster (shingles) and postherpetic neuralgia.

Herpes zoster (commonly referred to as "shingles") and postherpetic neuralgia result from reactivation of the varicella-zoster virus acquired during the primary varicella infection, or chickenpox. Whereas varicella is generally a disease of childhood, herpes zoster and post-herpetic neuralgia become more common with increasing age. Factors that decrease immune function, such as human immunodeficiency virus infection, chemotherapy, malignancies and chronic corticosteroid use, may also increase the risk of developing herpes zoster. Reactivation of latent varicella-zoster virus from dorsal root ganglia is responsible for the classic dermatomal rash and pain that occur with herpes zoster. Burning pain typically precedes the rash by several days and can persist for several months after the rash resolves. With postherpetic neuralgia, a complication of herpes zoster, pain may persist well after resolution of the rash and can be highly debilitating. Herpes zoster is usually treated with orally administered acyclovir. Other antiviral medications include famciclovir and valacyclovir. The antiviral medications are most effective when started within 72 hours after the onset of the rash. The addition of an orally administered corticosteroid can provide modest benefits in reducing the pain of herpes zoster and the incidence of postherpetic neuralgia. Ocular involvement in herpes zoster can lead to rare but serious complications and generally merits referral to an ophthalmologist. Patients with postherpetic neuralgia may require narcotics for adequate pain control. Tricyclic antidepressants or anticonvulsants, often given in low dosages, may help to control neuropathic pain. Capsaicin, lidocaine patches and nerve blocks can also be used in selected patients.

Acyclovir↗

[Varicella: how and when to start antiviral treatment].

The Meeting "An Update on Chickenpox" (Florence, 19-3-1993) has contributed to verify, in the light of the most recent acquisitions, the new guidelines for a correct rationale in the diagnosis and therapy of chickenpox. The present availability of an effective specific antiviral therapy for chickenpox (acyclovir) leads to a careful selection of patients to be treated. The high incidence of chickenpox morbidity keeps long unaltered and, beyond the usually benign onset of the primary infection in the child, the severity of this pathology in particular subjects and situations at risk is to be certainly underlined. Treatment is suggested for cases of chickenpox contracted inside the family. Generally, boys are at higher risk. Adolescents and adults, usually with a lower incidence, report a much higher severity of the acute onset and complications. Another category to be certainly treated is the one--in constant increase--of immunocompromised subjects. In any case, acyclovir treatment improves the symptomatologic evolution (pruritus and fever) and duration of clinical course. Among the progenitors of acyclovir, Valacyclovir seems to have the best prospects of success for the immediate future of antiviral therapy.

Acyclovir↗

Cost-consequence models for varicella-zoster virus infections.

Three cost-consequence models were developed for treatment of infections due to varicella-zoster virus (VZV) with acyclovir in immunocompetent patients--adult- and childhood-onset chickenpox, and herpes zoster (shingles) in adults. For chickenpox, separate models allow examination of differences in severity and impact of the disease for children and adults, as well as in the management of civilians and adults in military service. Each model includes direct medical costs, indirect costs and health-related productivity loss, symptom and quality of life impact, and model assumptions and conclusions. Alternatives of treatment and no treatment are addressed. Quality of life impact is conceptualized in terms of a quality-adjusted life-days decrement due to VZV symptoms of importance to the patient, such as pain, rash, and itching. As experience and data become available, alternative agents such as valacyclovir and famciclovir for the treatment of patients with herpes zoster should be included in the modeling process.

Acyclovir↗

Efficacy of famciclovir in the treatment of herpes zoster.

Although vidarabine was the first systemic antiviral drug for the treatment of acute herpes zoster, the agent now used most frequently is acyclovir, a far safer drug that became available a decade ago. However, even with widespread use of acyclovir, postherpetic neuralgia (PHN) remains a principal cause of postinfectious morbidity. Newer antiviral agents, such as famciclovir and valacyclovir, have recently been introduced for the treatment of uncomplicated herpes zoster. In a double-blind, randomized study, 500 mg of famciclovir three times daily for 7 days was compared with placebo; in a second study, 500 mg of famciclovir three times daily for 7 days was compared with 800 mg of acyclovir five times daily for 7 days. Famciclovir significantly reduced duration of viral shedding (P = 0.0001) and accelerated lesion resolution compared with placebo. Famciclovir was comparable to acyclovir for these acute parameters. Most importantly, famciclovir recipients lost PHN two times faster than those receiving placebo (P = 0.02 all patients; P = 0.004 patients > or = 50 years) resulting in a reduction in the median duration of PHN (56 days all patients; 100 days patients > or = 50 years). This reduction translated to a 3.5-month reduction in the median duration of PHN for patients 50 years or older, those at greatest risk for developing the most common complication of herpes zoster. Famciclovir 500 mg administered three times a day for 7 days is an effective and well-tolerated treatment for acute herpes zoster, and is the only oral antiviral agent proven to reduce the duration of PHN when administered during acute zoster infection.

2-Aminopurine↗

[Genital herpes with special emphasis on perinatal herpes simplex virus infection].

INTRODUCTION: The incidence of genital herpes is increasing worldwide and at present herpes simplex virus type 2 is the most common cause of genital ulceration all over the world. CLASSIFICATION: The International Herpes Management Forum (IHMF) was established in 1993, suggesting a new classification of genital herpes: primary genital herpes, non-primary genital herpes, recurrent genital herpes, first episode genital herpes, atypical genital herpes and asymptomatic HSV (herpes simplex virus) infection. DIAGNOSIS: Clinical diagnosis of genital herpes should be confirmed by laboratory techniques, whereas a positive HSV culture is the best test for confirming the clinical diagnosis. Serological testing, including Western blot assay, is not the method of choice for diagnosis genital herpes. THERAPY: Management of patients with genital herpes must include various antiviral drugs (acyclovir, valacyclovir, famiclovir), but also must take into consideration the patients' clinical and emotional issues. Patients with few recurrences are best managed with episodic antiviral therapy, but those with more frequent recurrences may find a long term suppressive therapy more beneficial. Herpes simplex virus is acquired during labor in about 90% of neonatal herpes virus cases with direct contact with infected maternal genital secretions, in 5% of cases in utero (ascending infection or transplacentary) and in another 5% of cases HSV is acquired post partum. Herpes simplex virus infection includes skin infection, eye and mouth manifestations, CNS diseases and disseminated disease with multiorgan involvement. CONCLUSION: In order to reduce the risk of HSV transmission to the infant IHMF has suggested management of pregnant women with primary genital herpes: delivery by Caesarean section between 34th week and term. Acyclovir treatment may reduce the viral load at delivery, but before this can generally be recommended, more data are still required.

Female↗

Genital Herpes: Treatment Guidelines.

Genital herpes, usually caused by herpes simplex virus type 2 (HSV-2), is the most common cause of genital ulceration. The primary episode of genital herpes is generally the most painful. Subsequent recurrences are generally milder and localized. Diagnosis is made clinically, but should be confirmed by culture or serology. Management includes antiviral drug therapy--acyclovir, valacyclovir, or famciclovir--as well as analgesics. In addition, patient counseling and education are vital. Antiviral treatment decreases the severity and duration of primary genital herpes and of recurrences, and it may be used as a continuous suppressive therapy to decrease the incidence of recurrence. Pregnant women who have a history of genital herpes or recent primary infection should deliver by cesarean section in the presence of genital lesions at labor or primary HSV infection at any time during the third trimester to prevent transmission to the neonate. Part 1, "Genital Herpes: Recognizing the Problem," addresses the problems involved in diagnosing the infection and quantifying the epidemic.

Journal Article↗

New antivirals with activity against varicella-zoster virus.

Herpes zoster is a serious medical problem, not only because of the discomfort associated with the acute rash, but also because of the potential for post-herpetic neuralgia. Acyclovir is currently the antiviral drug of choice for the treatment of herpes zoster. Efforts are underway to develop new drugs that have improved activity against varicella-zoster virus as well as more favorable pharmacokinetic properties. The goal of these efforts is to develop an orally administered antiviral drug that will accelerate the events of cutaneous healing as well as reduce the frequency and severity of post-herpetic neuralgia. Investigational drugs currently under evaluation include valaciclovir and famciclovir, the prodrugs of acyclovir and penciclovir, respectively. Two new uracil derivatives, sorivudine and BW882C87, with increased anti-varicella-zoster virus activity in vitro are also being studied.

2-Aminopurine↗

Review of research leading to new anti-herpesvirus agents in clinical development: valaciclovir hydrochloride (256U, the L-valyl ester of acyclovir) and 882C, a specific agent for varicella zoster virus.

Research leading to the new anti-herpesvirus compounds discussed here has come from three approaches. The first approach was directed towards improving the bioavailability of acyclovir by examining the potential of a variety of prodrugs, leading to the new compound valaciclovir hydrochloride. The second approach was to examine a large number of 5-substituted pyrimidines for activity against those viruses which were not as potently inhibited by acyclovir as are herpes simplex viruses, i.e., varicella zoster virus (VZV) and human cytomegalovirus (HCMV). This research led to the new chemical entity 882C for VZV. A third approach has been to examine drug combinations with acyclovir. This research led to the compound 348U, an inhibitor of herpes simplex virus ribonucleotide reductase which acts synergistically in combination with acyclovir. This manuscript will focus on the first two approaches leading to new compounds valaciclovir hydrochloride and 882C since Dr. Safrin details such background for 348U/acyclovir. Attempts to improve the bioavailability of acyclovir began a decade ago. Early prodrugs were compounds with alterations in the 6-substituent of the purine ring of acyclovir. The 6-amino congener required the cellular enzyme adenosine deaminase for conversion to acyclovir and the 6-deoxycongener was dependent on cellular xanthine oxidase for conversion. Neither of these prodrugs had a chronic toxicity profile in laboratory animals as good as acyclovir. Efforts were directed towards simpler esters and 18 amino acid esters were made. The pharmacokinetic profile of each prodrug was determined in rats by measuring the recovery of acyclovir in urine after oral dosing.(ABSTRACT TRUNCATED AT 250 WORDS)

Acyclovir↗

Valaciclovir (BW256U87): the L-valyl ester of acyclovir.

Valaciclovir (BW256U87) is an L-valyl ester of acyclovir, which is extensively and almost completely converted to acyclovir. In healthy human volunteers, single valaciclovir doses of 100-1000 mg resulted in dose-proportional increases in acyclovir area under the curve (AUC). The 1,000 mg dose produced an acyclovir peak plasma concentration (Cmax) of 5-6 micrograms/ml, AUC6 of 19 hr. micrograms/ml, time to maximum plasma concentration (Tmax) of 1-2 hr, and half-life (T1/2) of 2.8 hr. Plasma valaciclovir peak levels were < 0.3 micrograms/ml, and the prodrug was undetectable after 3 hr. Multiple valaciclovir doses of 250-2,000 mg given four times daily for 10 days resulted in dose-proportional increases in acyclovir Cmax. There were less than proportional increases in the AUCs. No serious or unexpected adverse events or laboratory abnormalities were reported. In volunteers with advanced human immunodeficiency virus (HIV) disease (absolute CD4 lymphocyte count < 150 cells/microliters), acyclovir and valaciclovir pharmacokinetic results were nearly identical to those in healthy volunteers. At the 2 g dose administered four times daily, steady-state acyclovir Cmax = 8.4 micrograms/ml, Tmax = 2.0 hr, AUC6 = 30.5 hr. micrograms/ml, and T1/2 = 3.3 hr. Nausea, vomiting, diarrhoea, and abdominal pain were commonly reported; however, only one adverse event (diarrhoea) was causally linked to valaciclovir exposure. There were no renal or neurologic adverse events. Valaciclovir is well absorbed and is rapidly converted to acyclovir, resulting in three- to fourfold higher acyclovir levels than can be achieved with oral acyclovir, even in patients with advanced HIV disease. The safety profile is generally favourable, with no evidence of nephrotoxicity or neurotoxicity.

Acyclovir↗