Long-term oral acyclovir therapy. Effect on recurrent infectious herpes simplex keratitis in patients with and without grafts

In vivo CRISPR gene editing in patients with herpetic stromal keratitis

In vivo CRISPR gene therapy holds large clinical potential, but the safety and efficacy remain largely unknown. Here, we injected a single dose of herpes simplex virus 1 (HSV-1)-targeting CRISPR formulation in the cornea of three patients with severe refractory herpetic stromal keratitis (HSK) during corneal transplantation. Our study is an investigator-initiated, open-label, single-arm, non-randomized interventional trial at a single center (NCT04560790). We found neither detectable CRISPR-induced off-target cleavages by GUIDE-seq nor systemic adverse events for 18 months on average in all three patients. The HSV-1 remained undetectable during the study. Our preliminary clinical results suggest that in vivo gene editing targeting the HSV-1 genome holds acceptable safety as a potential therapy for HSK.

Herpes simplex virus, varicella-zoster virus and cytomegalovirus keratitis: Facts for the clinician

Keratitis due to Herpes simplex virus (HSK), Varicella-Zoster virus (VZK) and Cytomegalovirus remains a frequent source of concern for many ophthalmologists. They are a frequent cause of emergency consultations at eye care centers and carry the risk of permanent loss of visual acuity or visual quality and/or chronic neurotrophic keratitis, resulting in a significant decrease in the quality of life. HSK and VZK can affect the corneal epithelium, stroma, or endothelium or a combination of layers. In contrast, most cases of CMV keratitis present as isolated endothelitis (CMVE), a clinical entity that has been described within the last 2 decades. These three types of viral keratitis are characterized by a high frequency of recurrences and each new episode increases the risk of sequelae. Hence, ophthalmologists must adapt the treatment to the clinical presentation of each recurrent episode in order to mitigate the immediate consequences of viral replication and the immune response on corneal transparency. In patients with frequent recurrences, preventive long-term antiviral treatment is strongly recommended. However, in some rare cases, continuous exposure to antivirals may promote the emergence of resistant viral strains, which can be difficult to manage. In the future, the introduction of new antiviral drugs, with differing modes of action compared to current medical therapy, could be an alternative until a truly effective preventive solution, such as a vaccine, is available.

Cataract surgery in herpes simplex virus ocular disease

PURPOSE

To investigate the outcomes and complications associated with cataract surgery in eyes with herpes simplex virus (HSV)-related anterior segment ocular disease.

SETTING

Public tertiary center in Auckland, New Zealand.

DESIGN

Retrospective observational cohort study.

METHODS

Clinical records of patients diagnosed with HSV-related keratitis and/or anterior uveitis who underwent subsequent cataract surgery in the affected eye were reviewed. Main outcomes measured were visual outcome, complications, and recurrence.

RESULTS

37 eyes of 37 patients were included. Intraoperative complications occurred in 1 patient (2.7%) with iris prolapse. Keratitis or uveitis recurred postoperatively in 17 patients (45.9%) 8 patients (22.5%); 22.5% experienced recurrences in the first year postoperatively. 1 case (2.7%) of postoperative cystoid macular edema and 1 (2.7%) postoperative endophthalmitis occurred. Corrected distance visual acuity at 3 months was >20/50 in 21 patients (70.0%), 20/50 to 20/200 in 4 patients (12.9%), and ≤20/200 in 6 patients (19.4%). Vision improved in 26 eyes (83.9%) and worsened in only 1 eye (3.2%). Risk for recurrent inflammation was associated with a greater number of recurrences prior to surgery (hazard rate [HR] 1.31), time quiescent prior to surgery (HR 0.48), and iris transillumination defect at preoperative assessment (HR 57.66).

CONCLUSIONS

Cataract surgery in eyes with previous HSV disease may improve visual acuity for most of the eyes but, overall, carries a guarded prognosis, particularly in eyes with corneal scarring. There is a significant risk for recurrent inflammation in the first year postoperatively. If possible, surgeons should ensure a period of disease quiescence prior to surgery.

Clinical outcomes of herpes simplex keratitis: Two-year experience from a quaternary eye care centre in Sydney, Australia

PURPOSE

To report anti-viral therapy and outcomes for patients with herpes simplex keratitis (HSK) in a quaternary centre in Sydney, Australia.

METHODS

A retrospective case review of patients who received anti-viral medications for any form of HSK was conducted. Cases were identified from pathology results, pharmacy records and hospital coding data from 2012 to 2013. Clinical details including initial anti-viral treatment and outcome were collated from the medical records. Outcome was determined from when initial anti-viral treatment was stopped or changed, and classified as either clinically resolved, partially resolved or worsened for therapeutic indication; or as either success or failure for prophylaxis.

RESULTS

Anti-viral therapy was given for therapeutic and prophylactic indications at presentation in 252 (85%) and 44 patients (15%), respectively. Topical aciclovir five times daily and valaciclovir in doses ranging from 500 mg to 1 g, one to three times daily were the preferred anti-viral therapies. One hundred and fourteen patients (n = 114/296, 38.5%) also received topical corticosteroids. An outcome was determined for 210/296 (71%) patients. For therapeutic indication, half of the patients (90/174) partially resolved within 8 days, with best outcomes achieved for endothelial HSK (8/11, 73%) and keratouveitis (21/36, 58%). Adverse events, observed in 20% (35/174) of patients, included corneal perforation (n = 8) and secondary bacterial keratitis (n = 6). Prophylaxis with antiviral therapy was successful in two-thirds of patients after 6 months.

CONCLUSIONS

Clinical and visual outcomes varied with the type of HSK and prescribed therapies. Diverse initial anti-viral therapies were identified; standardising them may improve outcomes.

Initial High-Dose Prophylaxis and Extended Taper for Mushroom Keratoplasty in Vascularized Herpetic Scars

PURPOSE

To report the outcomes of initial high-dose and extended taper of antiviral and steroid prophylaxis for the treatment of eyes with high-risk vascularized herpetic corneal scars that underwent 2-piece mushroom keratoplasty (MK).

DESIGN

Prospective interventional case series.

METHODS

In this single-center study, 52 consecutive eyes with vascularized (≥2 quadrants) herpetic corneal scars underwent 2-piece microkeratome-assisted MK. Initial high-dose and extended taper of combined oral and topical antiviral and steroid prophylaxis was administered. Outcome measures were best spectacle-corrected visual acuity (BSCVA), refractive astigmatism (RA), endothelial cell density, immunologic rejection, herpetic recurrence, and graft failure rates.

RESULTS

Excluding patients with vision-impairing comorbidities, baseline BSCVA (1.73 ± 0.67 logMAR) significantly improved annually during the first 2 years (P < .001, P = .016), reaching 0.17 ± 0.18 logMAR at year 2, and remaining stable up to 10 years (P = .662). At 2 years, 86% of eyes saw ≥20/40, 55% saw ≥20/25, and 18% saw ≥20/20 Snellen BSCVA. RA exceeded 4.5 diopters in 7% of cases after wound revision for high-degree astigmatism in 7 cases. Endothelial cell loss was 40.9% at 1 year with an annual decline of 3.1% over 10 years. The 10-year cumulative risk for immunologic rejection, herpetic recurrence, and graft failure was 9.7%, 7.8%, and 7.6%, respectively.

CONCLUSIONS

Initial high dose and extended taper of antiviral and steroid prophylaxis for MK in high-risk, vascularized herpetic corneal scars achieves clinical outcomes that remain stable for up to 10 years after surgery with minimal risk of immunologic rejection, herpetic recurrence and graft failure.

Oral antivirals for preventing recurrent herpes simplex keratitis in people with corneal grafts

BACKGROUND

Ocular herpes is a viral infection of the eye caused by the herpes simplex virus (HSV), a double-stranded DNA virus. Corneal scarring caused by herpes simplex keratitis (HSK) is the leading infectious cause of penetrating corneal graft in high-income countries. Acyclovir is an antiviral drug known to have a protective effect against recurrences in herpetic eye disease. While there are some studies which have evaluated the effects of intervention with oral antiviral in preventing such recurrences in people with corneal grafts, a systematic review of all comparative clinical trials has not been previously undertaken.

OBJECTIVES

To assess the efficacy of oral antivirals such as acyclovir in any dosage when taken for six months or more, in preventing recurrence of herpetic keratitis in people having corneal graft surgery for herpetic keratitis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 5), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to June 2016), Embase (January 1980 to June 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 1 June 2016. We handsearched conference proceedings and contacted authors of the included studies and researchers active in the field.

SELECTION CRITERIA

We included randomised controlled trials (RCTs). People enrolled in these trials had corneal grafts for HSK. The intervention was oral antivirals for six months or more following the corneal graft surgery, and this was compared to no treatment or placebo.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted trial investigators for any clarification or missing information. We graded the certainty of the evidence using GRADE.

MAIN RESULTS

We included three trials, involving 126 participants, comparing the use of oral acyclovir to no treatment or placebo. Two studies were conducted in single centres in Turkey and the USA, and one was multi-centred in the Netherlands. In general, the studies were poorly reported and it was difficult to judge the extent to which bias had been avoided.Oral acyclovir may reduce the risk of recurrence of herpetic keratitis (risk ratio (RR) 0.29, 95% confidence interval (CI) 0.13 to 0.64, 126 people, low-certainty evidence). Based on data from the included trials, this corresponds to approximately 23 fewer cases of HSK recurrence (95% CI 29 fewer cases to 12 fewer cases) per 100 corneal graft operations if oral acyclovir is used.Oral acyclovir may reduce the risk of graft failure (RR 0.40, 95% CI 0.16 to 0.97, 126 people, low-certainty evidence). Based on data from the included trials, this corresponds to approximately 13 fewer cases of graft failure (95% CI 18 fewer cases to 1 fewer cases) per 100 corneal graft operations if oral acyclovir is used.None of the studies reported any serious side effects of the antivirals necessitating stoppage or change. None of the trials reported outcomes over the long term (more than two years) or any data on quality of life.

AUTHORS' CONCLUSIONS

Compared to placebo or to no treatment, oral antiviral (acyclovir) may reduce the risk of recurrence of herpetic keratitis in the first 12 months in eyes that have undergone corneal graft surgery.

Delayed recurrence of acute retinal necrosis (ARN): A case series

PURPOSE

To report five cases of acute retinal necrosis (ARN) that reactivated in the same eye or presented in the contralateral eye between two and nineteen years after the initial episode of acute retinal necrosis.

CASES

Five patients with a previous history of ARN developed recurrent ARN infection following a lengthy latency period. In all five patients who initially presented with unilateral disease, four developed infection in the contralateral eye and one developed recurrent infection in the ipsilateral eye. Latency periods ranged from two to nineteen years, and final visual acuity in the affected eyes ranged from 20/30 to no light perception. Each patient was treated with antiviral medication for both the initial infection and for subsequent reactivations, but was not on long-term prophylaxis at the time of recurrent disease.

CONCLUSION

Although rare, delayed onset reactivation of ARN can occur in either the same eye or contralateral eye despite adequate treatment. While contralateral spread of initial infection is fairly common, these reactivations rarely occur more than six weeks after initial infection. Currently there are no guidelines for use of prophylactic antiviral medication to prevent late recurrence of ARN.

Ganciclovir ophthalmic gel 0.15% for the treatment of acute herpetic keratitis: background, effectiveness, tolerability, safety, and future applications

Eye disease due to herpes simplex virus (HSV) is a leading cause of ocular morbidity and the number one infectious cause of unilateral corneal blindness in the developed parts of the globe. Recurrent keratitis can result in progressive corneal scarring, thinning, and vascularization. Antiviral agents employed against HSV have primarily been nucleoside analogs. Early generation drugs included idoxuridine, iododesoxycytidine, vidarabine, and trifluridine. While effective, they tended to have low bioavailability and measurable local cellular toxicity due to their nonselective mode of action. Acyclovir 0.3% ointment is a more selective agent, and had become a first-line topical drug for acute HSV keratitis in Europe and other places outside of the US. Ganciclovir 0.15% gel is the most recently approved topical treatment for herpes keratitis. Compared to acyclovir 0.3% ointment, ganciclovir 0.15% gel has been shown to be better tolerated and no less effective in several Phase II and III trials. Additionally, topical ganciclovir does not cause adverse systemic side effects and is therapeutic at lower concentrations. Based on safety, efficacy, and tolerability, ganciclovir 0.15% gel should now be considered a front-line topical drug in the treatment of dendritic herpes simplex epithelial keratitis. Topics of future investigation regarding other potential uses for ganciclovir gel may include the prophylaxis of recurrent HSV epithelial keratitis, treatment of other forms of ocular disease caused by herpesviruses and adenovirus, and ganciclovir gel as an adjunct to antitumor therapy.

Evidence-based treatment of herpes simplex virus keratitis: a systematic review

Herpes simplex virus (HSV) keratitis is a common cause of ocular and visual morbidity. In this article, we systematically review published randomized clinical trials (RCTs) for HSV epithelial and stromal keratitis in order to establish a rational evidence-based foundation for treatment of these disorders. Articles for review were identified in the MEDLINE database from January 1, 1966, to May 30, 2006. Our review criteria stipulated that each study be performed in prospective, randomized, and double-blinded fashion, that it be controlled, and that it rely on specific clinical criteria for diagnosis and outcome. Of articles thus identified in the English language press, 38 articles met our review criteria, 30 for HSV epithelial keratitis and 8 (comprising 7 RCTs) for HSV stromal keratitis. From these studies, we concluded that the best evidence from treatment trials on HSV epithelial keratitis supports the use of topical trifluridine and topical or oral acyclovir, and suggests a possible additional benefit for topical interferon. The best evidence from RCTs for HSV stromal keratitis supports the use of topical corticosteroids given together with a prophylactic antiviral to shorten the duration of active HSV stromal keratitis, and the use of long-term suppressive oral acyclovir therapy to reduce the incidence of recurrent HSV keratitis.

Efficacy of oral antiviral prophylaxis in preventing ocular herpes simplex virus recurrences in patients with and without self-reported atopy

PURPOSE

To compare the efficacy of oral antiviral prophylactic treatment for herpes simplex virus (HSV) recurrences in patients with and without self-reported atopy.

DESIGN

Retrospective cohort comparative study.

METHODS

setting: Cornea Service, Wills Eye Hospital. study population: Patients who presented with previously diagnosed ocular HSV between March 2003 and March 2004. From 244 patients invited, 54 patients (58 eyes) were included. One hundred and ninety patients were excluded according to exclusion criteria: no active episode during follow-up, immunosuppression, less than one year of follow-up, or previous history of penetrating keratoplasty. The Questionnaire regarding history of atopic disease, considers: presence of allergic rhinitis, asthma or atopic dermatitis, and chart review of ocular history. main outcome measures: Incidence of all types of HSV recurrences with and without antiviral prophylaxis within each group and between groups. HSV episodes were classified into infectious, inflammatory, and mixed for analysis.

RESULTS

Atopic/nonatopic (P value): mean follow-up without prophylaxis 8.1 (+/- 8.2)/7.3 years (+/- 8.6) (P = .71); mean follow-up with prophylaxis 2.9 (+/- 2.3)/2.6 years (+/- 2.2) (P = .51); the effect of prophylaxis significantly reduced the all recurrences in both groups except in the inflammatory recurrences in the atopic group and in the mixed recurrences in both groups. Prophylaxis decreased infectious episodes by 44% in nonatopic and 76% in atopics and decreased inflammatory manifestations by 69% in the nonatopic group and 8% in the atopic group.

CONCLUSION

Antiviral prophylaxis for HSV recurrences was more effective in reducing infections in atopics and less effective in reducing inflammatory episodes in atopics versus nonatopics.

[Immunomodulation in penetrating keratoplasty. Current status and perspectives]

The immune privileged nature of the cornea contributes to the favourable outcome in corneal grafts. However, preventive measures are necessary to reduce allograft rejection particular in "high-risk" cases. Although corticosteroids are still a major component of our immunopharmacological armentarium, they might be supplemented by other more specific immunomodulating agents. The spectrum includes agents such as azathioprin, methotrexate or more specific calcineurin inhibitors affecting T-cells (cyclosporin A, FK506) and highly selective monoclonal antibodies directed against T-cell subpopulations and other targets. In order to better evaluate the risks and benefit of these agents, the properties of established and forthcoming agents are presented. In addition, this review attempts to address some new concepts of tolerance induction following penetrating keratoplasty.

Bilateral herpetic keratoconjunctivitis

PURPOSE

To review the clinical characteristics and visual outcomes of patients with bilateral herpetic keratitis.

DESIGN

Retrospective, noncomparative, observational case series.

PATIENTS AND METHODS

A retrospective review of medical records of 544 patients with herpes simplex virus (HSV) eye disease treated between January 1996 and September 2001 was performed at the Department of Ophthalmology, University of Minnesota. Seven patients (1.3%) with bilateral herpetic keratoconjunctivitis were identified.

RESULTS

In these seven patients, the age at the initial onset of corneal disease ranged from 7 weeks to 46 years, with a median of 18 years and a mean of 19.3 years. Five patients had systemic atopy, and two patients had severe ocular rosacea. Systemic immune disorders were noted in two patients. Recurrent blepharoconjunctivitis was noted in 8 eyes (57%), epithelial keratitis in 12 eyes (85.7%), stromal keratitis in 9 eyes (64.3%), necrotizing stromal keratitis in 5 eyes (35.7%), and progressive endotheliitis in 2 eyes (14.2%). Corneal complications included opacification, neovascularization, and corneal thinning or perforation. Penetrating keratoplasty was performed in 1 eye, in which endophthalmitis subsequently developed and which required enucleation. Four patients with continued use of oral antiviral prophylaxis (acyclovir 400 mg twice daily) since September 1999 showed significant decreases in recurrence. The average remission in these four patients was 1.7 years. The visual acuity at the last follow-up was 20/40 or worse in 6 eyes (42.8%).

CONCLUSIONS

In contrast to unilateral HSV keratitis, our patients with bilateral herpetic corneal infections had underlying atopy or immune deviations and evinced more protracted clinical courses. Long-term prophylactic antiviral treatment has reduced the incidence of recurrence in this group of patients.

[Corneal herpes: what's new?]

The prognosis of herpetic keratitis has been dramatically improved during the past years because of a better understanding of their physio-pathologic phenomenons, and mostly because of the use of very efficient antiviral drugs. Superficial keratitis are easily cured in most cases; deep stromal keratitis, that often require corticosteroid treatment, are more difficult to heal. Prophylactic treatment of the recurrences by oral antiviral drugs represents a promising new concept for herpetic keratitis.

The outcome of corneal grafting in patients with stromal keratitis of herpetic and non-herpetic origin

AIM

To evaluate the outcome of corneal grafting in patients with stromal keratitis of herpetic (HSK) and non-herpetic origin, using predefined diagnostic criteria and standardised postoperative therapeutic strategies.

METHODS

384 adult immunocompetent recipients of a corneal graft for herpetic (n = 186) or non-herpetic (n = 198) keratitis were followed up prospectively for up to 5 years.

RESULTS

The herpetic group displayed significantly more corneal vascularisation (p = 0.013), more epithelial defects (p = 0.049), lower corneal sensitivity (p <0.001), more graft rejection episodes (p = 0.002), and required larger grafts (p<0.001). However, the postoperative course of visual acuity, endothelial cell numerical density, and rate of graft failures were similar in both groups. After 5 years, cumulative probability of graft survival in HSK patients (40.85%) was similar to that observed in individuals with non-herpetic keratitis (50.15%; log rank = 0.874; relative risk: 1.04).

CONCLUSION

Despite a markedly higher preoperative risk profile in herpetic eyes, the functional outcomes of grafts in individuals with keratitis of herpetic or non-herpetic origin were similar. Probably the most important contribution is a consequent close follow up and a therapeutic strategy including systemic prophylaxis of viral recurrence and of graft rejection by well adopted local steroid therapy.

Intraocular lens implantation after penetrating keratoplasty

PURPOSE

We evaluated the clinical results of nonsimultaneous penetrating keratoplasty, cataract extraction, and intraocular lens (IOL) implantation (two-stage surgery) for combined corneal disease and cataract.

METHODS

Twenty-six eyes of 24 patients with an average age of 46 years who underwent two-stage surgery were studied retrospectively. Variables included visual acuity, refractive status, specular microscopy before and after IOL implantation (6 months), and the occurrence of graft failure. Astigmatism was corrected by suture removal and relaxing incision. The mean follow-up after IOL placement was 16 months.

RESULTS

Unaided visual acuity was 20/100 or better in 22 (83%) eyes after the second procedure. Twenty-one (81%) eyes had an aided visual acuity of at least 20/40. The mean refractive and absolute errors were -1.49 +/- 1.39 diopters (D) and 1.55 +/- 1.30 D, respectively. The mean keratometric and refractive cylinders were 3.50 D and 2.26 D, respectively. Nineteen (73%) eyes had a spherical equivalent refraction within 2 D of emmetropia. Anisometropia (> or =3 D) occurred in four (15%) eyes. The endothelial cell density, the coefficient of variation, and the percentage of hexagonal cells documented by specular microscopy were not significantly different before and after IOL implantation. Complications included three rejections, two cases of herpetic recurrence, and one late decompensation. Two graft failures (8%) occurred after secondary surgery.

CONCLUSION

The two-stage surgery is a safe and effective modality.

Current Australian practice in the prevention and management of corneal allograft rejection

PURPOSE

To determine current practices in the prevention and management of corneal allograft rejection in Australia.

METHODS

A questionnaire was circulated to attendees at the 1998 Eye Bank Meeting in Adelaide. Twenty-four responses were received and analysed.

RESULTS

All respondents used topical corticosteroids for routine prophylaxis and to treat established rejection episodes. Prednisolone acetate was the most frequently prescribed topical corticosteroid. Systemic non-steroidal immunosuppression was prescribed almost exclusively for high-risk grafts. Seventy-five per cent of surgeons used systemic antiviral agents for the treatment of graft rejection in patients with Herpes simplex keratitis.

CONCLUSION

There was a wide variation amongst surgeons in the choice of therapy for routine prophylactic immunosuppression as well as for the treatment of established corneal allograft rejection.

The evolution of antiviral therapy for external ocular viral infections over twenty-five years

PURPOSE

To review the past 25 years of the evolution of antiviral therapy for the treatment of common external ocular viral infections (herpes simplex virus type 1, varicella-zoster virus, and adenovirus).

METHODS

A broad-based literature review in the fields of virology, antiviral research, and ophthalmology will be carried out. The pathogenesis of the major external ocular viral infections and history of antiviral development will be cited. Important conceptual breakthroughs as well as historical landmarks will be emphasized.

RESULTS

The successful development of effective antivirals to treat the most common external ocular viral infections have dramatically reduced morbidity and sight loss. The immune pathogenesis of herpetic stromal keratitis is better understood.

CONCLUSIONS

Remarkable progress in the development of antiviral therapy has occurred over the past quarter century. Future needs include improved antivirals and immunomodulators and vaccines to prevent and treat herpetic ocular infections and adenovirus keratoconjunctivitis.

Oral acyclovir for the management of herpes simplex virus keratitis in children

PURPOSE

To evaluate the use of oral acyclovir in pediatric patients with herpes simplex virus (HSV) keratitis.

DESIGN

Retrospective noncomparative case series.

PARTICIPANTS

Seven pediatric patients seen at the University of Minnesota Hospitals and Clinics with herpes simplex virus (HSV) infectious epithelial keratitis between January 1992 and October 1998. Patient ages ranged from 6 weeks to 5 years at time of presentation with a median of 1.7 and mean of 1.9 years.

INTERVENTION

All patients received oral acyclovir; six of seven patients also received topical antiviral medications. Three of seven patients had topical antiviral therapy fail before being placed on oral acyclovir, and the remaining four patients were placed on oral acyclovir primarily.

RESULTS

All patients showed resolution of HSV infectious epithelial keratitis. Three patients have been maintained on prophylactic dosage of oral acyclovir because of recurrent disease or because they have been chronically treated with topical corticosteroids for immune stromal keratitis. All patients tolerated acyclovir well, and there were no adverse reactions.

CONCLUSIONS

Oral acyclovir is useful in treating HSV infectious epithelial keratitis in pediatric patients. It is beneficial in treating infectious epithelial keratitis and prophylactically either while treating with topical corticosteroids for immune stromal keratitis or for preventing recurrent infectious epithelial keratitis.

Acyclovir for the prevention of recurrent herpes simplex virus eye disease. Herpetic Eye Disease Study Group

BACKGROUND

Long-term treatment with antiviral agents has been shown to prevent recurrences of genital and orofacial herpes simplex virus (HSV) disease, but it is uncertain whether prophylactic treatment can prevent recurrences of ocular HSV disease.

METHODS

We randomly assigned 703 immunocompetent patients who had had ocular HSV disease within the preceding year to receive 400 mg of acyclovir or placebo orally twice daily. The study outcomes were the rates of development of ocular or nonocular HSV disease during a 12-month treatment period and a 6-month observation period.

RESULTS

The cumulative probability of a recurrence of any type of ocular HSV disease during the 12-month treatment period was 19 percent in the acyclovir group and 32 percent in the placebo group (P<0.001). Among the 337 patients with a history of stromal keratitis, the most common serious form of ocular HSV disease, the cumulative probability of recurrent stromal keratitis was 14 percent in the acyclovir group and 28 percent in the placebo group (P=0.005). The cumulative probability of a recurrence of nonocular (primarily orofacial) HSV disease was also lower in the acyclovir group than in the placebo group (19 percent vs. 36 percent, P<0.001). There was no rebound in the rate of HSV disease in the six months after treatment with acyclovir was stopped.

CONCLUSIONS

After the resolution of ocular HSV disease, 12 months of treatment with acyclovir reduces the rate of recurrent ocular HSV disease and orofacial HSV disease. Long-term antiviral prophylaxis is most important for patients with a history of HSV stromal keratitis, since it can prevent additional episodes and potential loss of vision.