Herpes simplex virus skin infection in man treated with idoxuridine in dimethyl sulphoxide. Results of double-blind controlled trial

Sensitivity of Types 1 and 2 Herpes Simplex Virus to 5-Iodo-2'-Deoxyuridine and 9-beta-d-Arabinofuranosyladenine

The sensitivities of 21 strains of herpes simplex virus (HSV), 13 type 1 strains and 8 type 2 strains, to 5-iodo-2'-deoxyuridine (IUdR) and 9-beta-d-arabinofuranosyladenine (ara-A) were evaluated by the plaque-suppression test in chick embryo fibroblast (CEF), WI-38, and HeLa cell cultures. In CEF, type 1 strains were considerably more sensitive to the inhibitors than were the type 2 strains. In WI-38, the type 1 strains were more sensitive than the type 2 strains to IUdR; however, the two serotypes were equally sensitive to ara-A. In HeLa cells, the differences in sensitivity to IUdR between the two serotypes were less. Eight HeLa-adapted strains (four type 1 and four type 2) evaluated in HeLa cell cultures were equally sensitive to IUdR; the type 2 strains were slightly more sensitive than type 1 strains to ara-A. These results demonstrate the wide variation in sensitivity of HSV types 1 and 2 to antiviral agents which results from differences in the cell culture system and passage history of the strains.

A double-blind, placebo-controlled study of topical tetracaine in the treatment of herpes labialis

BACKGROUND

Before the September 1996 approval of 1% penciclovir cream for the treatment of herpes labialis, no other prescription topical therapy was approved for the treatment of this recurrent viral disease affecting approximately 20% of the adult population of the United States. Local anesthetics, such as tetracaine, have been used in over-the-counter topical products, but are only labeled for the relief of pain and itching associated with cold sores and fever blisters.

OBJECTIVE

The purpose of this study was to determine whether a topical preparation of a tetracaine cream is safe and effective in the treatment of recurrent herpes labialis in immunocompetent patients.

METHODS

A double-blind, placebo-controlled study was conducted to assess the relative effectiveness and safety of 1.8% tetracaine equivalent in a cream base versus placebo in the treatment of herpes labialis in immunocompetent adults. In this study, patients applied medication up to 6 times daily until the lesions healed (scab loss), but for no more than 12 days. The patients were monitored on the day of enrollment, once during the course of treatment, and at a final visit after the lesions had healed. Patients assessed themselves the day of scab formation and the day the scab fell off. They also graded, on a daily basis, their perception of relief from itching and pain and the overall benefit.

RESULTS

The results from 72 patients (35 = placebo; 37 = active) showed that scab formation occurred in a mean of 2.4 +/- 0.27 days for the placebo group and 2. 3 +/- 0.26 days for the active group. Healing time (scab loss) occurred in a mean 7.2 +/- 0.36 days for the placebo group and in 5. 1 +/- 0.35 days in the active group. The difference observed for healing time between the placebo and the active tetracaine cream was statistically significant (P =.0002). This represents an approximately 30% reduction in the healing time for the active group compared with the placebo group. In addition, the study patients ranked the benefit of their treatment on a daily basis and graded the overall benefit of the therapy at their final visit. The ranking was on a 1 to 10 index scale (1 = no benefit at all; 10 = very effective treatment). At the final visit there was a statistically significant difference in the benefit index for active preparation versus placebo for this subjective evaluation (placebo index, 5.9 +/- 0.6; active index, 7.3 +/- 0.48 [P =.0359]). The subjects also evaluated relief from itching and pain on a daily basis. Relief from itching was significantly greater in the active group than in the placebo group on days 2 and 3 after initiation of the treatment. Pain was not found to be severe in either the placebo or active treatment groups. At day 2 of treatment and beyond, pain scores never were greater than 3.2 +/- 0.28 for active on a scale in which 1.0 represented "no pain at all" and 10 represented "most severe pain imaginable." Although mean values for pain were always less for the active therapy, lesional pain scores never reached statistically significant lower values for active compared with placebo.

CONCLUSION

Our findings indicate that a 1.8% topical tetracaine cream, when applied frequently, significantly reduces the healing time of recurrent herpes labialis lesions. Additionally, it is perceived by the study subjects to reduce itching of the lesions and to have a beneficial overall effect.

Determination of 2'-deoxy-5-iodouridine and its metabolite 5-iodouracil by high-performance liquid chromatography with ultraviolet absorbance detection in human serum

A new assay is described for 2'-deoxy-5-iodouridine, a drug employed as an antiviral agent by topical application. The parent drug, its systemic metabolite 5-iodouracil and an internal standard (5-iodouridine) were extracted from salted serum by an ethyl acetate partition at pH 6.7, back-extracted in alkalinized water and injected into a reversed-phase column. Potassium phosphate buffer-acetonitrile (95:5, v/v) eluted the analytes at a flow-rate of 1.5 ml/min. Detection was at 290 nm. The method proved to be linear in the 100-2000 ng/ml range.

Topical treatment of cutaneous herpes simplex virus infections

Topical antiviral chemotherapy has a number of potential advantages over systemic drug delivery for the treatment of cutaneous herpes simplex virus infections, including convenience; higher target tissue drug levels and greater efficacy; and specific targeting of the drug to the site of infection, with reduced cost and reduced exposure of the remainder of the body to drug side effects. Realization of these possibilities has been slow in part because of the paucity of 'active' topical drug formulations with effective penetration-enhancing agents and a technical barrier-our failure as yet to measure drug levels in the epidermis, which could guide formulation development. Recent success with a topical treatment for herpes simplex labialis should stimulate continued laboratory and clinical research in this field.

Pediatric herpetic hand infections

Fourteen cases of pediatric herpetic hand infection were admitted over a 15-year period. Five cases were documented by viral culture, four by Tzanck smear; the remainder were diagnosed on clinical grounds. The natural history of herpetic hand infections is similar in adult and pediatric populations. Adult infections are most frequently found in medical and dental personnel; pediatric infections are most common in children between 5 months and 6 years of age. Whereas adult infections are usually the result of exogenous occupational or sexual exposure, 11 (80%) of 14 pediatric cases exhibited coexistent oral lesions. Treatment in all cases is nonsurgical; resolution is complete within 3 to 4 weeks. Antibiotics are indicated only in the advent of bacterial superinfection.

Glycyrrhizin gel as a vehicle for idoxuridine--I. Clinical investigations

The therapeutic efficacy of a new formulation that incorporates 0.2% IDU in glycyrrhizin gel has been tested on patients who suffer from herpes of the lips and nose. The preparation was significantly more effective than a commercial 0.5% IDU ointment. It reduced the healing time and produced an almost instantaneous relief from pain. The higher efficacy of the new preparation may be ascribed to the reported anti-inflammatory and antiviral activities of glycyrrhizin together with an enhanced permeation of the IDU through the skin.

Pathogenesis of recurrent herpes simplex labialis. IV. Maturation of lesions within 8 hours after onset and implications for antiviral treatment

In order to define precisely the development of recurrent herpes simplex labialis, we studied 122 untreated or placebo-treated patients who were first seen when their lesions were less than 24 hours old. Subjects were divided into three groups with lesion ages of 0 to 8, 9 to 16, or 17 to 24 hours. Lesion pain, area, and virus titer were determined for each group at the time of the first clinic visit and again on the following day, and the change in lesion severity between visits was examined. The proportion of patients with increasing or decreasing lesion values was markedly influenced by lesion age. Among 0- to 8-hour-old lesions, area, pain, and virus titer increased in 27%, 21%, and 39% of the subjects, respectively, compared to 10%, 6%, and 0% among those lesions were 17 to 24 hours old at the first visit. A decrease in lesion area, pain, and virus titer was seen in 14%, 24%, and 12% of 0- to 8-hour-old lesions, compared with 35%, 65%, and 54% of the lesions in the 17- to 24-hour age group (p = 0.03, 0.006, and 0.0002). The majority of patients in each age group had mature lesions that remained unchanged or decreased in severity between visits. The possible benefits of antiviral chemotherapy to established lesions are limited because only a small number of untreated patients have progressive disease.

Topical carbenoxolone sodium in the management of herpes simplex infection

Topical carbenoxolone was discovered by chance to be a highly effective anti-viral agent and was subsequently used in the management of Herpetic gingivostomatitis and recurrent Herpes labialis. A marked reduction in the healing time and pain associated with these lesions was noted. A discussion of the possible mechanisms of action of carbenoxolone is included.

Penetration of guinea pig skin by acyclovir in different vehicles and correlation with the efficacy of topical therapy of experimental cutaneous herpes simplex virus infection

Inadequate penetration of antiviral agents through the stratum corneum of the skin may be one of the limiting factors in the topical therapy of recurrent cutaneous herpes simplex virus infections in humans. In vitro studies of the penetration of the nucleoside analog acyclovir (ACV) through guinea pig skin demonstrated a marked increase in drug flux when ACV was formulated in dimethyl sulfoxide (DMSO), compared with water or polyethylene glycol (PEG) as the vehicle. To examine whether the increased transcutaneous flux of ACV effected by DMSO was meaningful in vivo, topical 5% ACV in DMSO was evaluated for the treatment of cutaneous herpes simplex virus infection in guinea pigs and compared with topical 5% ACV in PEG. When compared with infection sites treated with the vehicle alone, ACV in DMSO produced a greater percent reduction than did ACV in PEG in median lesion number (8 versus 58%; P less than 0.001), median lesion area (35 versus 73%; P = 0.001), and median lesion virus titer (21 versus 84%; P = 0.08). We conclude that DMSO is a highly effective vehicle for topical administration of ACV and is superior to PEG in our model. Careful choice of vehicle and consideration of transcutaneous penetration may be important for realization of the full potential of topical antiviral therapy in humans.

Treatment of first episodes of genital herpes simplex virus infection with oral acyclovir. A randomized double-blind controlled trial in normal subjects

We performed a double-blind placebo-controlled trial of oral acyclovir in the treatment of first episodes of genital herpes simplex virus infections in 48 young adults (31 women and 17 men). Subjects were randomized to receive either placebo or acyclovir (200 mg per dose) five times daily for 10 days; they were examined on at least eight visits until healed and at monthly visits thereafter. Acyclovir treatment, as compared with placebo, significantly reduced virus shedding, new lesion formation after 48 hours, and the duration of genital lesions in both men and women. The total duration and severity of clinical symptoms (such as pain, adenopathy, dysuria, and malaise) were significantly reduced by acyclovir in both men and women by the third and fourth day, respectively (P less than or equal to 0.025), as compared with placebo. No toxicity was observed. Recurrence rates have so far been similar in placebo and acyclovir recipients. Oral acyclovir treatment of first-episode genital herpes simplex virus infections is clinically effective, but it does not seem to prevent virus latency or associated recurrent disease.

Combined chemotherapy of cutaneous herpes simplex infection of the guinea pig

Cutaneous infection of guinea pigs with HSV1 was topically treated from 2 to 6 days post infection with 7 antiherpetic substances. Phosphonoformic acid and acyclovir were found to be highly effective; trifluorothymidine, thymine arabinoside, ethyldeoxyuridine, and adenine arabinoside monophosphate all had some therapeutic effect in decreasing order, whereas iododeoxyuridine was ineffective. The efficacy of treatment was evaluated from cutaneous lesion scores by the Wilcoxon rank test. The substances were combined in marginally effective concentrations. From the 21 combinations, acyclovir + phosphonoformic acid, acyclovir + thymine arabinoside, and phosphonoformic acid + thymine arabinoside suggested a synergistic interaction, which appeared significant for acyclovir + phosphonoformic acid.

Arabinosyladenine monophosphate in genital herpes: a double-blind, placebo-controlled study

A double-blind, placebo-controlled study was performed in 55 male patients with recurrent herpes simplex genitalis. The 29 patients who received topical arabinosyladenine monophosphate (ara-AMP) showed no significant difference in viral shedding, duration of pain, healing time or development of new lesions as compared to 26 placebo-treated patients. Ara-AMP was well-tolerated when topically applied. Serum neutralizing antibody titers did not change significantly during the acute and convalescent periods of the patient's recurrent HSG attacks. We conclude that ara-AMP, when applied topically as a 10% gel five times a day within 24 h of onset of recurrent HSG, does not influence the virologic and clinical evolution of the recurrent episode.

Topical 5 percent acyclovir in polyethylene glycol for herpes simplex labialis. Antiviral effect without clinical benefit

A double-blind, placebo-controlled trial of topical 5 percent acyclovir in polyethylene glycol was conducted among 208 patients with herpes simplex labialis. Reduced excretion of virus from lesions was seen in the subgroup of patients who entered the study within eight hours of lesion onset, but no differences were noted in the patients who began treatment nine to 25 hours after onset. No clinical benefit from treatment with acyclovir was observed.

Contact allergy to idoxuridine. Sensitization following treatment of herpes zoster

A total of 45 of 60 patients with herpes zoster previously treated with topical idoxuridine 5-40% in dimethylsulfoxide were patch tested 2 years later with idoxuridine 0.5% and 5% in petrolatum. Three (7%) showed positive reactions. Idoxuridine is considered a weak sensitizer, but in strong concentrations and in active solvents, which increases absorption, there seems to be a risk of sensitization.

Ineffectiveness of topical adenine arabinoside 5'-monophosphate in the treatment of recurrent herpes simplex labialis

The ability of topical 10 per cent adenine arabinoside 5'-monophosphate to decrease the severity and frequency of recurrent herpes simplex labialis was evaluated in a double-blind, randomized study of 233 patients at three collaborating institutions. Nine clinical and four virologic measurements were used to evaluate drug efficacy during a single episode. No statistically significant improvement in any measurement was seen in the drug-treated patients. Analyses according to institution and age, stage and size of lesion before therapy also indicated no benefit attributable to the drug. There was no effect of the drug on the rate of recurrence of herpes simplex labialis. We conclude that, despite activity against herpes simplex virus infection in tissue culture and in some laboratory animal models, topical use of the drug is ineffective against recurrent herpes simplex labialis. This may be due to failure of the drug to penetrate the skin.

Double blind trial in the treatment of herpes simplex and herpes zoster with adenine arabinoside and idoxuridine

In a double blind trial adenine arabinoside (Vidarabine) and Idoxuridine (IDU) were tested in herpes simplex and herpes zoster infections. Adenine arabinoside covered 19 patients with HSV and 6 with HZ while IDU 19 with HSV and 6 with HZ. From the statistical analysis it was found that Vidarabine acts shorter than IDU in HSV P less than 0.01, while in HZ no significant difference P less than 0.5 was found, possibly due to the small number of patients tested.

Current approaches to the diagnosis of herpes genitalis

The current methods of diagnosing and treating herpes genitalis in clinics for sexually transmitted diseases in England and Wales are reported. Virus cultures were used as a diagnostic test in some or all patients in nearly two-thirds of clinics. Darkground examinations were performed on all or selected patients in most clinics, but fewer than half the clinics performed them on three or more separate occasions. In over 80% of clinics attempts were made to see some or all contacts of patients with herpes. The treatments prescribed varied, the commonest being saline washes, idoxuridine, and oral antibiotics. Serological tests were repeated after the disappearance of the lesions in 90% of clinics, while in 60% of clinics women with herpes genitalis were advised to have cytological examination at regular intervals in future. The importance of excluding syphilis in patients presenting with genital ulceration, the most appropriate treatments for herpes, and the possible association between the disease and cervical carcinoma are discussed.

A trial of adenine arabinoside in genital herpes

Twenty-four episodes of genital herpes in 22 men, all confirmed by virus isolation, were studied in a double blind trial. They were treated either with 3% adenine arabinoside (Ara-A) in petrolatum ointment base or with the base alone applied four times daily for one week. The lesions were counted and sketeched on days 0, 2, and 7. There was no demonstrable advantage to be gained from the use of Ara-A ointment. The results of the Papanicolaou smears and virus isolation agreed in the diagnosis of 75% of cases. The presence of continuing lesions or fresh ones in some patients after the acute phase of the initial or recurrent attack of herpes necessitates the man taking precautions on resuming sexual intercourse.

Chemotherapy of genital herpes simplex virus type 2 infections of female hamsters

The antiviral activity of 1-beta-d-arabinofuranosylcytosine (ara-C, cytarabine, Cytosar), 5-iodo-2'-deoxyuridine (IdUrd), 9-beta-d-arabinofuranosyladenine (ara-A), and disodium phosphonoacetate (PAA) have been compared in herpes simplex virus type 2 (HSV-2)-infected primary rabbit kidney cells and in female hamsters with genital HSV-2 infection. In vitro, ara-C and IdUrd were more active than ara-A, and PAA was least active. In female hamsters with genital HSV-2 infection, intravaginal treatment with PAA or ara-A was more effective than either ara-C or IdUrd. PAA was more active than ara-A when treatment was initiated early (1 h) after infection. The activity of PAA was greatly reduced if initiation of treatment was delayed for 24 h. Both PAA and ara-A reduced the virus titers of the vagina and protected hamsters from death when the drugs were given by either the intravaginal or subcutaneous route, with intravaginal treatment being more effective.

Antiviral therapy

The current status of antiviral therapy is reviewed, including discussion of older approaches together with more recently developed chemotherapy. Following the introduction dealing with pathophysiological aspects of virus disease, the different approaches to antiviral therapy are presented. The reasons for the slow progress in antiviral therapy are discussed. These include: 1. the necessity of intracellular penetration of drugs acting on viral replication; 2. the severe toxicity of most antiviral drugs; 3. the narrow antiviral spectrum of most of these agents; 4. the difficulty of making a rapid etiological diagnosis in view of the necessity of starting (specific?) treatment early in the course of the disease; 5. the difficult evaluation of beneficial as compared with deleterious effects of antiviral therapy. After a detailed review of clinically tested substances, including immunoglobulins, synthetic antiviral drugs (amantadine, nucleoside analogs, thiosemicarbazones and photodynamic dyes) and interferon, a guide concerning indications and application of specific antiviral therapy is presented. Although at present there are few indications, clinicians should be aware of the (present and future) possibilities of antiviral therapy.

The management of ocular herpesvirus infections

The many treatment methods in current use for every known complaint only seem to aggravate the difficulty of treating ocular herpes simplex virus (HSV) infections, which are generally self-limited in the immunocompetent host. The cornea is already a somewhat immune-deficient tissue since its lack of blood vessels separates it partially from the host, and treatment with glucocorticoids, which are immunosuppressive, increases the risk of damaging complications such as scarring, prolonged morbidity, bacterial or fungal superinfection, and the occasional corenal perforation. Accepted methods of treatment of specific lesions, are discussed, as are some methods that are not yet accepted, but which seem promising. Herpes zoster may result in scarring and significant loss of vision even without the use of glucocorticoids, the disease often manifesting itself in the already compromised host. The major complication is postherpetic neuralgia. None of the available treatment methods has been fully satisfactory, and every effort should be made to prevent eye lesions in patients with early infection of the ophthalmic branch of the trigeminal nerve. Stimulation of cellular immunity by various means appears to offer some new promise for control of the disease. Management of varicella, cytomegalovirus, and infectious mononucleosis are also discussed.

Failure of neutral-red photodynamic inactivation in recurrent herpes simplex virus infections

Because photodynamic inactivation of herpes simplex virus infections may not be free of hazard, the efficacy of photodynamic inactivation with neutral red and light was evaluated in a placebo-controlled study of 170 episodes of recurrent herpes simplex virus infection in 96 patients. The preparation of neutral red that was used was shown to photoinactivate herpes simplex virus in vitro, but had no significant effect on the rate of resolution of herpetic lesions (P greater than 0.10) or on the frequency of subsequent recurrences (P greater than 0.10), except for orolabial lesions, in which an adverse effect on the rate of subsequent recurrences was observed (P less than 0.05). In the absence of demonstrated efficacy, the routine use of neutral red and light in patients with recurrent herpes simplex virus infections should be discontinued. Furthermore, other photoactive dyes should not be used until their efficacy has been demonstrated by suitably controlled clinical trials.

Clinical evaluation of kethoxal against cutaneous herpes simplex

A 2.5% preparation of kethoxal in cream was compared with the cream placebo for efficacy against cutaneous herpes simplex in a double-blind clinical study. The kethoxal formulation was not significantly more effective than the placebo. This conclusion was based on subjective impressions of the patients, observations by the physicians, and quantitative measurement of herpesvirus recovered from the lesions. It was suggested that the lack of clinical activity, in contrast to the marked activity against experimental infections in laboratory animals, resulted from the fact that high levels of herpesvirus were already present in the skin before symptoms were noted.

Treatment of zoster with idoxuridine in dimethyl sulphoxide. Results of two double-blind controlled trials

The antiviral effect of 5% idoxuridine in dimethyl sulphoxide intermittently applied and of 40% idoxuridine in dimethyl sulphoxide continuously applied for four days to the lesions in patients with zoster of recent onset was studied in two double-blind controlled trials. Most, but not all, of the patients receiving intermittent active treatment had pain for a short period only. The effect of continuous treatment was striking: pain had disappeared within nine days in all the patients and healing was accelerated. The results were statistically significant.