Pulse versus continuous terbinafine for onychomycosis: A randomized, double-blind, controlled trial

Antifungal Selection for the Treatment of Onychomycosis: Patient Considerations and Outcomes

Onychomycosis, a common fungal nail infection, affects >20% of adults over age 60 and >50% of people over age 70. Onychomycosis may cause pain, psychosocial problems, and secondary infections, therefore meriting treatment. This review describes the range of treatment modalities, including FDA-approved systemic drugs and topical therapies. Additionally, new and emerging oral and topical therapies are discussed. We emphasize the importance of tailoring onychomycosis therapy to individual patient characteristics, comorbidities, preferences, extent of nail involvement, and fungal species, such that physicians may optimize treatment outcomes, patient satisfaction, and safety.

Onychomycosis: Old and New

Onychomycosis is a common chronic fungal infection of the nail that causes discoloration and/or thickening of the nail plate. Oral agents are generally preferred, except in the case of mild toenail infection limited to the distal nail plate. Terbinafine and itraconazole are the only approved oral therapies, and fluconazole is commonly utilized off-label. Cure rates with these therapies are limited, and resistance to terbinafine is starting to develop worldwide. In this review, we aim to review current oral treatment options for onychomycosis, as well as novel oral drugs that may have promising results in the treatment of onychomycosis.

Combination Therapy Should Be Reserved as Second-Line Treatment of Onychomycosis: A Systematic Review of Onychomycosis Clinical Trials

Onychomycosis is the most common nail disease encountered in clinical practice. Its importance extends well beyond aesthetics, often causing pain, difficulty with ambulation and performing daily activities, and impairing quality of life. Many patients fail to achieve cure with antifungal monotherapy and recurrences are common. Combination therapy has therefore gained considerable interest, given the potential for drug synergy and prevention of antifungal resistance, but it has not been well studied. A systematic review of onychomycosis medication only, as well as medication and procedural (laser, debridement, photodynamic therapy), clinical or randomized controlled trials evaluating combination vs. monotherapies was performed. After exclusions, 30 studies were included in the final analysis. There were conflicting results for medication-only trials, with some showing significant benefit of combination therapy over monotherapy, however, trials were not robustly designed and lacked sufficient follow-up. Procedural studies also lacked long-term follow-up, and failed to demonstrate efficacy in some severe onychomycosis cases. Considering the high cure rates demonstrated in pivotal antifungal monotherapy trials, and conflicting results, costs, and safety concerns associated with combination therapy, we recommend that combination therapy be reserved as second-line treatment options in patients with poor prognostic factors or for those who failed monotherapy for onychomycosis.

Race reporting and representation in onychomycosis clinical trials: A systematic review

BACKGROUND

Onychomycosis is the most common nail disease seen in clinical practice. Inclusion of diverse groups in onychomycosis clinical trials subjects is necessary to generalise efficacy data.

OBJECTIVES

We aimed to systematically review race and ethnicity reporting and representation, as well as, treatment outcomes in onychomycosis clinical trials.

METHODS

A PubMed search for onychomycosis clinical trials was performed in August 2020. Primary clinical trial data were included and post hoc analyses were excluded. Categorical variables were compared using chi-squared and Fisher's exact tests. Statistical significance was set at p < .05. Photos in articles were categorised by Fitzpatrick skin type.

RESULTS

Only 32/182 (17.5%) trials reported on race and/or ethnicity and only one trial compared treatment efficacy in different subgroups. Darker skin colours were infrequently depicted in articles. Topical treatment, location with ≥1 US-based site, industry funding type and publication date after 2000 were significantly associated with reporting of racial/ethnic data (p < .05 for all comparisons).

LIMITATIONS

Demographics on excluded subjects and methods of recruitment were not available. Assigning Fitzpatrick skin type is inherently subjective.

CONCLUSIONS

This study highlights a need for consistent reporting of races and ethnicities of onychomycosis clinical trial participants with subgroup analyses of treatment efficacies.

Safety of current therapies for onychomycosis

INTRODUCTION

Onychomycosis is the most common nail disease seen in clinical practice. Treatment options include systemic and topical therapies, as well as devices. Following clinical and mycologic diagnosis, treatment must be individualized, accounting for disease severity, infecting organism(s), comorbidities, patient characteristics and drug/device efficacy. Safety is the most important consideration in choosing the most appropriate therapeutic modality.

AREAS COVERED

This review covers currently available treatments for onychomycosis, with an emphasis on safety and tolerability. Medications and devices were analyzed for side effects, drug-drug interactions, and safety during pregnancy and breastfeeding.

EXPERT OPINION

Systemic antifungals offer greater efficacy for onychomycosis treatment but are limited by risks of systemic toxicity and drug-drug interactions. The risk of terbinafine-induced hepatotoxicity is negligible in healthy patients. Systemic therapies, especially azole antifungals, are associated with numerous drug-drug interactions, some of which are life-threatening and fatal. Thus, a detailed medication history is critical before prescribing these medications. Topical antifungals are well tolerated and generally safe, with only potential local side effects. Systemic and topical onychomycosis treatments should not be prescribed during pregnancy and breastfeeding. Laser therapy is likely less effective than systemic and topical therapies, but may be safely used during pregnancy and breastfeeding.

Methylene blue vs methyl aminolevulinate photodynamic therapy in combination with oral terbinafine in the treatment of severe dermatophytic toenail onychomycosis: Short- and long-term effects

BACKGROUND

Photodynamic therapy (PDT) kills target microorganisms via reactive oxygen species (ROS) production. PDT seems to be a good alternative treatment option for onychomycosis.

OBJECTIVE

To compare the efficacy of combined therapies based on oral terbinafine (TN) plus adjunctive PDT mediated by methylene blue (MB) (TN + MB/PDT) or methyl aminolevulinate (MAL) (TN + MAL/PDT) in the treatment of onychomycosis.

METHODS

Twenty patients affected by severe dermatophyte onychomycosis in the nails of the big toe (>60% disease involvement of target nail) received oral TN for 12 weeks and concomitantly were randomly allocated to receive nine sessions, separated by 2-week intervals, of urea (40%) plus a PDT protocol mediated by MB (TN + MB/PDT: group I) or mediated by MAL (TN + MAL/PDT: group II). Clinical and mycological efficacy was evaluated at 16-, 40- and 52-week follow-up.

RESULTS

Both protocols showed a significant decrease in Onychomycosis Severity Index (OSI) scores (P < .05), from 24.2 ± 4.6 to 0.7 ± 0.6 (group I)) and from 18.5 ± 10.1 to 2.1 ± 2.0 (group II). No side effects or complications were reported in any of the combinations used. Mycological cure rates were significantly higher during the last third of the evaluated period of time, reaching 100% and 90% in group I and group II, respectively, at the 52-week follow-up. In both modalities, complete cure was achieved in 70% of the patients at the 52-week follow-up.

CONCLUSIONS

TN + MB/PDT and TN + MAL/PDT show similar outcomes in the treatment of toenails with severe onychomycosis. PDT is an effective method to accelerate the TN-mediated healing process.

Oral antifungal therapies for toenail onychomycosis: a systematic review with network meta-analysis toenail mycosis: network meta-analysis

Aim: Toenail fungal infections account for half of all nail disease cases, and a highly negative impact on patient quality of life. Our aim was to compare the efficacy and safety of commercially available oral antifungals for onychomycosis.Methods: A systematic review was performed in PubMed and Scopus. Randomized controlled trials evaluating the effect of oral antifungals on mycological cure, discontinuation and adverse events were included. Network meta-analyses were built for each outcome. Results were reported as odds ratios (OR) with 95% credibility intervals (CrI). Ranking probabilities were calculated by surface under the cumulative ranking analysis (SUCRA).Results: We included 40 trials (n = 9568). Albaconazole 400 mg (OR 0.02 [95% CrI 0.01-0.07] versus placebo), followed by posaconazole 200-400 mg and terbinafine 250-350 mg were considered the best therapies (SUCRA probabilities over 75%). For the networks of discontinuation and individual adverse events, few significant differences among treatments were observed, but itraconazole 400 mg was considered the safest drug (SUCRA around 25%). Albaconazole 400 mg, posaconazole 200-400 mg, and terbinafine 250-350 mg were the most effective therapies for onychomycosis, while itraconazole 400 mg was the safest.Conclusion: The profile of albaconazole and posaconazole compared to current first-line therapies should be further investigated in well-designed trials.

The efficacy and safety of pulse vs. continuous therapy for dermatophyte toenail onychomycosis

BACKGROUND

Onychomycosis is a chronic, fungal infection of the nails. Complete cure remains challenging, but oral antifungal medications have been successful in managing the fungus for a significant proportion of patients. Treatment with these drugs can be continuous or intermittent, albeit the evidence on their relative efficacies remains unclear.

OBJECTIVE

To determine the relative effectiveness and safety of pulse versus continuous administration, of three common oral therapies for dermatophyte onychomycosis, by conducting multiple-treatment meta-analysis.

METHODS

This systematic review and network meta-analysis compared the efficacy (as per mycological cure) and adverse event rates of three oral antifungal medications in the treatment of dermatophyte toenail onychomycosis, namely terbinafine, itraconazole and fluconazole. A total of 30 studies were included in the systematic review, while 22 were included in the network meta-analysis.

RESULTS

The likelihood of mycological cure was not significantly different between continuous and pulse regimens for each of terbinafine and itraconazole. Use of continuous terbinafine for 24 weeks - but not 12 weeks - was significantly more likely to result in mycological cure than continuous itraconazole for 12 weeks or weekly fluconazole for 9-12 months. Rank probabilities demonstrated that 24-week continuous treatment of terbinafine was the most effective. There were no significant differences in the likelihood of adverse events between any continuous and pulse regimens of terbinafine, itraconazole and fluconazole. Drug treatments were similar to placebo in terms of their likelihood of producing adverse events.

CONCLUSION

More knowledge about the fungal life cycle and drugs' pharmacokinetics in nail and plasma could further explain the relative efficacy and safety of the pulse and continuous treatment regimens. Our results indicate that in the treatment of dermatophyte toenail onychomycosis, the continuous and pulse regimens for terbinafine and itraconazole have similar efficacies and rates of adverse events.

A Week of Oral Terbinafine Pulse Regimen Every Three Months to Treat all Dermatophyte Onychomycosis

Terbinafine has proved to treat numerous fungal infections, including onychomycosis, successfully. Due to its liver metabolization and dependency on the cytochrome P450 enzyme complex, undesirable drug interaction are highly probable. Additionally to drug interactions, the treatment is long, rising the chances of the appearance of side effects and abandonment. Pharmacokinetic data suggest that terbinafine maintains a fungicidal effect within the nail up to 30 weeks after its last administration, which has aroused the possibility of a pulse therapy to reduce the side effects while treating onychomycosis. This study's goal was to evaluate the effectiveness of three different oral terbinafine regimens in treating onychomycosis due to dermatophytes. Sixty-three patients with onychomycosis were sorted by convenience in three different groups. Patients from group 1 received the conventional terbinafine dose (250 mg per day for 3 months). Group 2 received a monthly week-long pulse-therapy dose (500 mg per day for 7 days a month, for 4 months) and group 3 received a 500 mg/day dose for 7 days every 3 months, totaling four treatments. There were no statistical differences regarding the effectiveness or side effects between the groups. Conclusion: A quarterly terbinafine pulse regimen can be a possible alternative for treating onychomycosis caused by dermatophytes.

In vitro Evaluation of Photodynamic Effects Against Biofilms of Dermatophytes Involved in Onychomycosis

Dermatophytes are the most common cause of onychomycosis, counting for 90% fungal nail infection. Although dermatophyte pathogens are normally susceptible to antifungal agents, onychomycosis often results in refractory chronic disease, and the formation of biofilms frequently underlines the inadequate responses and resistance to standard antifungal treatment. Numerous in vitro and in vivo antimicrobial photodynamic therapy (aPDT) studies have shown biofilm eradication or substantial reduction, however, such investigation has not yet been expanded to the biofilms of dermatophytes involved in onychomycosis. To shed a light on the potential application of aPDT in the clinic management of onychomycosis, in particular with the manifestation of dermatophytoma, we investigated photodynamic effects on the viabilities and the drug susceptibilities of the biofilm of dermatophytes in vitro. Here, methylene blue at the concentration of 8, 16, and 32 μg/ml applied as photosensitizing agent and LED (635 ± 10 nm, 60 J/cm²) as light source were employed against six strains of Trichophyton rubrum, ten strains of Trichophyton mentagrophytes and three strains of Microsporum gypseum isolated from clinical specimens. Our results indicated highly efficient photodynamic inhibition, exhibiting CFU (colony forming unit) reduction up to 4.6 log₁₀, 4.3 log₁₀, and 4.7 log₁₀ against the biofilms formed by T. rubrum, T. mentagrophytes, and M. gypseum, respectively. Subjected biofilms displayed considerable decreases in SMICs (sessile minimum inhibitory concentrations) to multiple antifungal agents when compared with untreated groups, indicating the biofilms of dermatophytes became more susceptible to conventional antifungal drugs after aPDT. Additionally, the obliteration of biofilm after aPDT could be observed as shattered and ruptured structures being evident in SEM (Scanning Electron Microscopy) images. These findings suggest that aPDT is an attractive alternative treatment holding great promise for combating recalcitrant onychomycosis associated with the biofilm formation.

Confirmatory Testing Prior to Initiating Onychomycosis Therapy Is Cost-Effective

Background:

Onychomycosis can be investigated by sampling. Information gleaned includes nail bed involvement, nail plate penetration, fungal viability, and species identification. Testing samples can confirm a diagnosis. While diagnostic testing is considered useful in directing therapy, a substantial number of clinicians do not confirm diagnosis prior to treatment.

Objectives:

The aim of this study is to quantify the benefit of confirmatory testing prior to treating toenail onychomycosis.

Methods:

The cost of mycological cure (negative potassium hydroxide and negative culture) and the cost-effectiveness of confirmatory testing were determined using the average cost of potassium hydroxide (KOH), culture, periodic acid–Schiff (PAS), efinaconazole, ciclopirox, terbinafine, and itraconazole. Costs were obtained through literature searches, public domain websites, and telephone surveys to local pharmacies and laboratories. To represent the potential risks of prescribing onychomycosis treatment, the costs associated with liver monitoring, potential life-threatening adverse events, and drug-drug interactions were obtained through public domain websites, published studies, and product inserts.

Results:

PAS was determined to be the most sensitive confirmatory test and KOH the least expensive. The overall cost of an incorrect diagnosis (no confirmatory test used) ranged between $350 and $1175 CAD per patient for treatment of 3 infected toenails. Comparatively, performing confirmatory testing prior to treatment decreases the overall cost to $320 to $930, depending on the therapy, physician, and test.

Conclusions:

It is preferred to diagnose onychomycosis prior to treatment. Furthermore, there are cost savings when confirmatory testing is performed before initiating treatment with both topical and oral antifungals in Canada.

Oral antifungal medication for toenail onychomycosis

BACKGROUND

Fungal infection of the toenails, also called onychomycosis, is a common problem that causes damage to the nail's structure and physical appearance. For those severely affected, it can interfere with normal daily activities. Treatment is taken orally or applied topically; however, traditionally topical treatments have low success rates due to the nail's physical properties. Oral treatments also appear to have shorter treatment times and better cure rates. Our review will assist those needing to make an evidence-based choice for treatment.

OBJECTIVES

To assess the effects of oral antifungal treatments for toenail onychomycosis.

SEARCH METHODS

We searched the following databases up to October 2016: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of included and excluded studies for further references to relevant randomised controlled trials (RCTs). We sought to identify unpublished and ongoing trials by correspondence with authors and by contacting relevant pharmaceutical companies.

SELECTION CRITERIA

RCTs comparing oral antifungal treatment to placebo or another oral antifungal treatment in participants with toenail onychomycosis, confirmed by one or more positive cultures, direct microscopy of fungal elements, or histological examination of the nail.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 48 studies involving 10,200 participants. Half the studies took place in more than one centre and were conducted in outpatient dermatology settings. The participants mainly had subungual fungal infection of the toenails. Study duration ranged from 4 months to 2 years.We assessed one study as being at low risk of bias in all domains and 18 studies as being at high risk of bias in at least one domain. The most common high-risk domain was 'blinding of personnel and participants'.We found high-quality evidence that terbinafine is more effective than placebo for achieving clinical cure (risk ratio (RR) 6.00, 95% confidence interval (CI) 3.96 to 9.08, 8 studies, 1006 participants) and mycological cure (RR 4.53, 95% CI 2.47 to 8.33, 8 studies, 1006 participants). Adverse events amongst terbinafine-treated participants included gastrointestinal symptoms, infections, and headache, but there was probably no significant difference in their risk between the groups (RR 1.13, 95% CI 0.87 to 1.47, 4 studies, 399 participants, moderate-quality evidence).There was high-quality evidence that azoles were more effective than placebo for achieving clinical cure (RR 22.18, 95% CI 12.63 to 38.95, 9 studies, 3440 participants) and mycological cure (RR 5.86, 95% CI 3.23 to 10.62, 9 studies, 3440 participants). There were slightly more adverse events in the azole group (the most common being headache, flu-like symptoms, and nausea), but the difference was probably not significant (RR 1.04, 95% CI 0.97 to 1.12; 9 studies, 3441 participants, moderate-quality evidence).Terbinafine and azoles may lower the recurrence rate when compared, individually, to placebo (RR 0.05, 95% CI 0.01 to 0.38, 1 study, 35 participants; RR 0.55, 95% CI 0.29 to 1.07, 1 study, 26 participants, respectively; both low-quality evidence).There is moderate-quality evidence that terbinafine was probably more effective than azoles for achieving clinical cure (RR 0.82, 95% CI 0.72 to 0.95, 15 studies, 2168 participants) and mycological cure (RR 0.77, 95% CI 0.68 to 0.88, 17 studies, 2544 participants). There was probably no difference in the risk of adverse events (RR 1.00, 95% CI 0.86 to 1.17; 9 studies, 1762 participants, moderate-quality evidence) between the two groups, and there may be no difference in recurrence rate (RR 1.11, 95% CI 0.68 to 1.79, 5 studies, 282 participants, low-quality evidence). Common adverse events in both groups included headache, viral infection, and nausea.Moderate-quality evidence shows that azoles and griseofulvin probably had similar efficacy for achieving clinical cure (RR 0.94, 95% CI 0.45 to 1.96, 5 studies, 222 participants) and mycological cure (RR 0.87, 95% CI 0.50 to 1.51, 5 studies, 222 participants). However, the risk of adverse events was probably higher in the griseofulvin group (RR 2.41, 95% CI 1.56 to 3.73, 2 studies, 143 participants, moderate-quality evidence), with the most common being gastrointestinal disturbance and allergic reaction (in griseofulvin-treated participants) along with nausea and vomiting (in azole-treated participants). Very low-quality evidence means we are uncertain about this comparison's impact on recurrence rate (RR 4.00, 0.26 to 61.76, 1 study, 7 participants).There is low-quality evidence that terbinafine may be more effective than griseofulvin in terms of clinical cure (RR 0.32, 95% CI 0.14 to 0.72, 4 studies, 270 participants) and mycological cure (RR 0.64, 95% CI 0.46 to 0.90, 5 studies, 465 participants), and griseofulvin was associated with a higher risk of adverse events, although this was based on low-quality evidence (RR 2.09, 95% CI 1.15 to 3.82, 2 studies, 100 participants). Common adverse events included headache and stomach problems (in griseofulvin-treated participants) as well as taste loss and nausea (in terbinafine-treated participants). No studies addressed recurrence rate for this comparison.No study addressed quality of life.

AUTHORS' CONCLUSIONS

We found high-quality evidence that compared to placebo, terbinafine and azoles are effective treatments for the mycological and clinical cure of onychomycosis, with moderate-quality evidence of excess harm. However, terbinafine probably leads to better cure rates than azoles with the same risk of adverse events (moderate-quality evidence).Azole and griseofulvin were shown to probably have a similar effect on cure, but more adverse events appeared to occur with the latter (moderate-quality evidence). Terbinafine may improve cure and be associated with fewer adverse effects when compared to griseofulvin (low-quality evidence).Only four comparisons assessed recurrence rate: low-quality evidence found that terbinafine or azoles may lower the recurrence rate when compared to placebo, but there may be no difference between them.Only a limited number of studies reported adverse events, and the severity of the events was not taken into account.Overall, the quality of the evidence varied widely from high to very low depending on the outcome and comparison. The main reasons to downgrade evidence were limitations in study design, such as unclear allocation concealment and randomisation as well as lack of blinding.

Improving Cure Rates in Onychomycosis

Background:

Onychomycosis is a persistent fungal nail infection that is notoriously hard to treat. Approximately 20% to 25% of patients with onychomycosis do not respond to treatment, and 10% to 53% of patients relapse. As such, successful treatment is imperative for long-term disease management.

Objective:

To identify ways to improve cure rates for onychomycosis.

Method:

The literature on onychomycosis treatment and recurrence was reviewed to summarize treatment approaches and suggest strategies to increase cure rates.

Results and Conclusion:

To improve treatment success in onychomycosis, we suggest the following measures be followed: (1) onychomycosis must be correctly diagnosed, (2) the treatment regimen should be tailored to the individual patient, (3) the efficacy of antifungals must be maximized, and (4) recurrence must be prevented.

Pharmacoeconomic Assessment of Ciclopirox Topical Solution, 8%, Oral Terbinafine, and Oral Itraconazole for Onychomycosis

Most pharmacoeconomic data available for antifungal agents are based on US or European cost parameters. Similar data have not been reported in a Canadian health care system. A pharmacoeconomic analysis was performed considering the costs of drug acquisition and medical management, which were representative of the Canadian health care system, for each of the therapies approved for use in toenail onychomycosis in Canada: continuous oral terbinafine, oral pulse itraconazole, and topical ciclopirox 8% nail lacquer. A survey of provincial fee schedules was conducted to determine the representative costs of parameters relating to onychomycosis treatment, such as consultation visit cost, return visit cost, mycology testing, liver function testing, and complete blood count analysis. Manufacturers' costs were used to calculate representative drug acquisition costs. Meta-analysis was used to determine the average mycologic cure rates of each therapy, and the medical literature was consulted to determine the relapse rates for each therapy. Ciclopirox nail lacquer had the lowest drug acquisition costs compared with continuous terbinafine and pulse itraconazole ($197.89 vs $311.39 and $323.40, respectively). Using the pharmacoeconomic model with three 1-year treatment phases, in which failures or relapses were re-treated with the primary drug, the expected cost per patient was $601.52 with ciclopirox nail lacquer, $746.72 with oral terbinafine, and $938.42 with itraconazole. The main analysis assumed that two bottles of ciclopirox nail lacquer were required per treatment. The cost for the ciclopirox lacquer exceeded continuous terbinafine but remained lower than pulse itraconazole when three bottles of ciclopirox nail lacquer were considered in the calculation of cost per mycological cure. A variety of relapse rates were tested, and ciclopirox using two or fewer bottles remained cost-effective compared with continuous terbinafine or pulse itraconazole, regardless of the relapse rate. Where three bottles are required, the cost-effectiveness of ciclopirox nail lacquer is less than that of continuous terbinafine but more cost-effective than that of pulse itraconazole.

Eficacia y seguridad de la terbinafina oral en pauta intermitente o pulsátil versus pauta continua para el tratamiento de la onicomicosis en mayores de 18 años

<p>La onicomicosis es una enfermedad que compromete las uñas y afecta el 5% de la población mundial. Objetivo. Determinar la efectividad y seguridad de la terbinafina oral en pauta intermitente versus continua para la onicomicosis en mayores de 18 años. Materiales y métodos. A través de una búsqueda sistemática electrónica en Cochrane, Medline, Embase, LILACS y Opengrey se identificaron ensayos clínicos aleatorizados paralelos, excluyendo cruzados, conglomerados o clúster. Se aplicó el RevMan 5.3 para revisiones sistemáticas de ensayos clínicos. Mediante búsqueda sistemática se identificaron ensayos clínicos aleatorizados paralelos en pacientes mayores de 18 años, de sexo masculino o femenino, humanos, en idioma inglés y español, sin límite de tiempo de publicación y cuyo desenlace fue la curación clínica y micológica, incluyendo efectos adversos leves. Se valoró el riesgo de sesgo; se utilizó RR como medida del efecto, IC95% para variables dicotómicas; la unidad de análisis fue el paciente y la estimación agrupada se calculó usando un modelo de efectos aleatorios para variables dicotómicas —método de Mantel-Haenszel en RevMan 5.3—. Resultados. El RR agrupado fue de 1.13 (IC95%: 1.06-1.2) indicando que la falla del tratamiento con terbinafina intermitente es 1.1 veces más probable que con terbinafina continua. Su RR agrupado dio 0.923 (IC95%: 0.77-1.09) indicando 7.7% de mayor probabilidad de desarrollar eventos adversos con terbinafina continua que con intermitente. Conclusiones. La terbinafina intermitente tiene menor éxito de cura clínica y micológica que la continua; su RR corregido demuestra que la pauta intermitente es 13% menos eficiente que la continua. Clínicamente los hallazgos son significativos pero estadísticamente falta poder en los estudios y un mayor tamaño de muestra agrupado para mejorar la evidencia.</p>

Onychomycosis treated with a dilute povidone-iodine/dimethyl sulfoxide preparation

Background

Povidone–iodine (PVP-I) 10% aqueous solution is a well-known, nontoxic, commonly used topical antiseptic with no reported incidence of fungal resistance. We have been using a low-dose formulation of 1% PVP-I (w/w) in a solution containing dimethyl sulfoxide (DMSO) in our clinical practice for a variety of indications. Presented here is our clinical experience with this novel formulation in a severe case of onychomycosis that was resistant to any other treatment.

Findings

A 49-year-old woman who had been suffering from severe onychomycosis for years presented after failing to find any remedy including over the counter (OTC), topical, and systemic oral prescribed therapies.

Conclusion

The topical povidone–iodine/DMSO system was very effective in this case at alleviating the signs and symptoms of onychomycosis. This novel combination warrants further investigation in randomized, controlled trials to further elucidate its clinical utility.

Oral therapy for onychomycosis: an evidence-based review

INTRODUCTION

Onychomycosis is a very common fungal infection of the nail apparatus; however, it is very hard to treat, even when the causative agent is identified, and usually requires prolonged systemic antifungal therapy. Until the 1990s, oral treatment options included only griseofulvin and ketoconazole, and the cure rate was very low. New generations of antimycotics, such as fluconazole, itraconazole and terbinafine have improved treatment success.

METHODS

Literature was identified by performing a PubMed Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, and Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) search. Prospective and randomized clinical trials were chosen to be included in this review. Forty-six trials were included.

RESULTS

Fluconazole, itraconazole and terbinafine are effective in the treatment of onychomycosis and have a good safety profile. When a dermatophyte is the pathogen, terbinafine produces the best results. For Candida and nondermatophyte infections, the azoles, mainly itraconazole, are the recommended therapy.

CONCLUSION

In the majority of the studies, terbinafine treatment showed a higher cure ratio than the other drugs for dermatophyte onychomycosis.

"In vitro" antifungal activity of ozonized sunflower oil on yeasts from onychomycosis

The "in vitro" antifungal activity of ozonized sunflower oil (Bioperoxoil®) was tested on 101 samples of yeasts originating from onychomycosis using the disk diffusion method. The oil was efficacious against several clinical fungal strains: Candida parapsilosis, Candida albicans, Trichosporon asahii, Candida tropicalis and Candida guilliermondii.

Comparison of once-daily versus twice-weekly terbinafine administration for the treatment of canine Malassezia dermatitis - a pilot study

BACKGROUND

Terbinafine, an allylamine antifungal, is used in pulsatile dose regimens for superficial mycoses in human medicine.

OBJECTIVES

To compare the clinical efficacy of twice-weekly versus once-daily terbinafine administration to determine whether preliminary proof-of-concept evidence exists for pulsatile administration of terbinafine in the treatment of canine Malassezia dermatitis and to determine whether twice-weekly treatment results in fewer clinical and owner-perceived adverse events.

ANIMALS

Twenty client-owned dogs with Malassezia dermatitis.

METHODS

In this randomized, single-blinded clinical trial, dogs were randomly assigned to receive terbinafine (30 mg/kg) either once daily for 21 days (n = 10) or once daily on two consecutive days per week for six doses (n = 10). On day 0 and day 21, a mean yeast count was calculated from eight anatomical locations via adhesive tape-strip cytology, clinical lesion scores were assigned to the same locations, and owners assessed pruritus using a visual analog scale.

RESULTS

There was no significant difference between treatment groups with respect to the reduction in mean yeast count (P = 0.343) and clinical lesion scores (P = 0.887). Pruritus measured by visual analog scale was significantly decreased in the twice-weekly treatment group compared with the daily treatment group (P = 0.047). Seven of 20 dogs had a clinically measurable or owner-reported adverse event during treatment that included gastrointestinal disturbances, excessive panting and elevated hepatic enzymes, with no significant difference noted between treatment groups.

CONCLUSIONS AND CLINICAL IMPORTANCE

This pilot study indicates that twice-weekly terbinafine administration may be an effective alternative treatment for canine Malassezia dermatitis and merits further investigation.

Clinical trial to compare the effectiveness of two concentrations of the Ageratina pichinchensis extract in the topical treatment of onychomycosis

The plant species Ageratina pichinchensis has been used, for many years, in Mexican traditional medicine for the treatment of superficial mycosis.

AIM OF THE STUDY

This study compared the therapeutic effectiveness and tolerability of two concentrations of the standardized extract from Ageratina pichinchensis (12.6 and 16.8%) on patients with clinical and mycological diagnosis of mild and moderate onychomycosis.

MATERIALS AND METHODS

Two identical phytopharmaceuticals (containing the standardized extract from Ageratina pichinchensis) in nail lacquer solution for topical administration were evaluated in a double-blind clinical trial. Treatments were administered for 6 months to patients distributed in two groups.

RESULTS AND DISCUSSION

Of 122 patients who agreed to participate in the study, 103 (84.4%) concluded the treatment. The therapeutic effectiveness exhibited by the 12.6% Ageratina pichinchensis extract was 67.2%, while that of the 16.8% Ageratina pichinchensis extract was 79.1%. Regarding clinical evolution, analysis of results at the end of treatment evidenced that the 16.8% concentration possesses higher therapeutic effectiveness with a significant statistical difference (p=0.010). No treatment produced side effects.

CONCLUSION

Both concentrations of phytopharmaceuticals possess high rates of effectiveness on patients with mild and moderate onychomycosis, and the formulation with a 16.8% concentration possesses higher effectiveness.

Intermittent versus continuous terbinafine in the treatment of toenail onychomycosis: A randomized, double‐blind comparison

BACKGROUND

Terbinafine is an established drug for the treatment of toenail onychomycosis. Minimizing the total dose of terbinafine and giving it intermittently could improve tolerability as well as compliance, provided efficacy is not compromised.

OBJECTIVE

Two identical trials were conducted to compare the efficacy, safety and tolerability of the current standard regimen of terbinafine 250 mg daily with a new formulation of terbinafine given intermittently for three cycles of 2 weeks of treatment (350 mg daily) followed by 2 weeks off treatment.

METHODS

A total of 2005 patients with a clinical diagnosis of subungual onychomycosis of the large toenail confirmed by microscopy and culture for a dermatophyte were recruited into the two trials and treated for 12 weeks.

RESULTS

Patients with onychomycosis of prolonged duration (mean 9 years) and a median nail involvement of 63% with or without spikes, lateral involvement and white superficial onychomycosis (WSO) were included in the trial. The studies found a significant difference (p<0.05) in favour of standard daily dosing with terbinafine. Response rates for the primary variable complete cure (mycological and clinical cure) were lower with the new formulation in both Trial I (-5.8%; 95% CI -11.8, 0.07) and Trial II (difference -5.9%; 95% CI -12, 0.1). Both treatments were equally well tolerated, with approximately 11% of patients in both groups reporting at least one treatment-related adverse event.

CONCLUSIONS

Pulsed dosing with terbinafine did not provide any clear safety advantages and was significantly less effective. Consequently, continuous treatment with terbinafine tablets remains the optimal therapy for onychomycosis.

Toenail onychomycosis in diabetic patients: issues and management

Diabetes mellitus may be associated with serious sequelae, such as renal disease, retinopathy, and diabetic foot. A recent large prospective study has shown that onychomycosis is among the most significant predictors of foot ulcer. As the severity of onychomycosis may be associated with the length of time the individual has had the infection, early intervention is advisable owing to the progressive nature of the fungal infection. If left untreated, toenails can become thick, causing pressure and irritation, and thus act as a trigger for more severe complications. In the treatment of onychomycosis, compliance and drug interactions are important considerations, as diabetic patients frequently take concomitant medications. Terbinafine and itraconazole have been investigated for the treatment of onychomycosis in diabetic patients and have been shown to have efficacy and safety profiles comparable to those in the nondiabetic population. Data from clinical trials and postmarketing surveillance suggest that drug interactions resulting in hypoglycemia may not be an important issue when itraconazole and terbinafine are used to treat diabetic patients receiving concomitant hypoglycemic medications. Patient advice and education in improved foot care are an integral part of onychomycosis management, and help achieve long-term cure and reduce the complications of diabetic foot.

Update on terbinafine with a focus on dermatophytoses

Since terbinafine was introduced on the world market 17 years ago, it has become the leading antifungal for the treatment of superficial fungal infections, aided by unique pharmacologic and microbiologic profiles. This article reviews mode of action, antimycotic spectrum and disposition profile of terbinafine. It examines the data, accumulated over 15 years, on the comparative efficacy of terbinafine (vs griseofulvin, itraconazole, fluconazole) in the management of the infections for which it is primarily indicated (eg, dermatophytoses) and provides a brief discussion on its use for the treatment of non-dermatophyte infections. Finally, the available data on the newest topical and systemic formulations are introduced.

A new concept in the topical treatment of onychomycosis with cyanoacrylate, undecylenic acid, and hydroquinone

The authors report a pilot study of a new approach for the topical treatment of onychomycosis using physiologic principles of fungal growth and serial debridement. In total, 154 patients were studied for 1 year with mild, moderate, and severe nail disease. Negative mycologic cultures in these 3 groups were 100%, 65%, and 35%, respectively. All patients reported subjective improvement in the first 3 months.

Validity of self-reported nail counts in patients with onychomycosis: A retrospective pilot analysis

BACKGROUND

Onychomycosis (fungal infection of the toenails or fingernails) is common, affecting up to 8% of the general population. Telephone and mailed surveys conducted to study this disease are usually completed via patient self-report. The validity of the counts of diseased nails reported by the patients participating in these surveys has not been established.

OBJECTIVE

The aim of this study was to assess the interrater agreement between patient and health care professional (HCP) counts of affected nails in patients with onychomycosis.

METHODS

Patient and HCP counts of infected toenails and fingernails corresponding to a total of 567 patients originating from 3 different clinical trials were retrospectively analyzed. All these patients were initially classified as mycologically positive for toenail onychomycosis, and all 3 trials used identical self-administered questions regarding counts of infected toenails and fingernails. The level of agreement between patient versus HCP counts of infected toenails and fingernails (based on collapsed and uncollapsed counts) was measured using the quadratically weighted kappa statistic.

RESULTS

Thirty-eight percent (213/554, 95% confidence interval [CI] = 35% to 43%) of the 554 patients with self-reported and HCP counts of infected toenails had exact agreement; for these 554 patients, quadratically weighted kappa = 0.47 (95% CI: 0.40 to 0.54). The highest agreement rates-79, 62, and 50%-correspond to the patients with HCP counts of affected toenails equaling 1, 2, and 10, respectively; that is, HCP counts at the extremes. The agreement rates ranged from 3% to 31% for the remaining patients with HCP counts between 3 and 9. Patients tended to undercount affected toenails, irrespective of the number of affected toenails counted by HCPs. No statistically significant association was found between agreement rates and whether or not the patients had been previously treated for toenail onychomycosis (P = .91). A marginally nonsignificant association of increasing agreement rates with increasing disease duration was observed (P = .06). Among the patients who reported one or more affected fingernails (n = 122), percent agreement was similar to that of toenails (41%, 95% CI: 33.0 to 50.0%).

LIMITATIONS

This pilot study is limited by its retrospective design, its homogeneous group of patients (predominantly white, male veterans), and the fact that information on intraobserver and interobserver reliability was not obtained from all of the 3 clinical trials, the sources for this analysis.

CONCLUSIONS

Patients tend to undercount affected nails as compared to HCPs. Reliance on self-reported counts in epidemiological surveys may lead to an inaccurate, underestimate of disease severity.

The safety of oral antifungal treatments for superficial dermatophytosis and onychomycosis: a meta-analysis

PURPOSE

We estimated the absolute risks of treatment termination and incidence of adverse liver outcomes among all commonly used oral antifungal treatments for superficial dermatophytosis and onychomycosis.

METHODS

MEDLINE, EMBASE, and Cochrane Library were searched to identify randomized and nonrandomized controlled trials, case series, and cohort studies published before December 31, 2005. Two reviewers independently applied selection criteria, performed quality assessment, and extracted data. Treatment arms with the same regimen in terms of drug, type (continuous or intermittent), and dosage were combined to estimate the risk of an outcome of interest.

RESULTS

We identified 122 studies with approximately 20,000 enrolled patients for planned comparison. The pooled risks (95% confidence intervals) of treatment discontinuation resulting from adverse reactions for continuous therapy were 3.44% (95% confidence interval [CI], 2.28%-4.61%) for terbinafine 250 mg/day; 1.96% (95% CI, 0.35%-3.57%) for itraconazole 100 mg/day; 4.21% (95% CI, 2.33%-6.09%) for itraconazole 200 mg/day; and 1.51% (95% CI, 0%-4.01%) for fluconazole 50 mg/day. For intermittent therapy, the pooled risks were as follows: pulse terbinafine: 2.09% (95% CI, 0%-4.42%); pulse itraconazole: 2.58% (95% CI, 1.15%-4.01%); intermittent fluconazole 150 mg/week: 1.98% (95% CI, 0.05%-3.92%); and intermittent fluconazole 300 to 450 mg/week: 5.76% (95% CI, 2.42%-9.10%). The risk of liver injury requiring termination of treatment ranged from 0.11% (continuous itraconazole 100 mg/day) to 1.22% (continuous fluconazole 50 mg/day). The risk of having asymptomatic elevation of serum transaminase but not requiring treatment discontinuation was less than 2.0% for all treatment regimens evaluated.

CONCLUSION

Oral antifungal therapy against superficial dermatophytosis and onychomycosis, including intermittent and continuous terbinafine, itraconazole, and fluconazole, was associated with a low incidence of adverse events in an immunocompetent population.

Reliability of self-reported willingness-to-pay and annual income in patients treated for toenail onychomycosis

BACKGROUND

Willingness-to-pay (WTP) is a health economics measure that has recently been used for skin diseases to evaluate patients' quality of life. However, the reliability of this measure has not been investigated in the dermatology literature and is essential in validating its use in health services research.

OBJECTIVES

This study evaluated the test-retest reliability of self-reported annual income and WTP, a health economics measure of disease impact, in patients with toenail onychomycosis.

METHODS

Forty-six patients enrolled in a randomized clinical trial comparing two different dosing regimens of terbinafine completed a self-administered questionnaire at baseline and 1 month later. The questionnaire asked: (i) how much patients would be willing to pay for a theoretical treatment with a cure rate of 85% for their current onychomycosis (10 categories: $0-50, $51-100, to > $800); and (ii) annual income (10 categories: $0-10,000 to > $200,000).

RESULTS

Forty-four patients reported WTP at both visits, and 55% reported the same WTP. The quadratic-weighted (Fleiss-Cohen) kappa statistic indicated moderate agreement (kappa = 0.50, 95% confidence interval, CI 0.24-0.75, P < 0.01) as did the Spearman rank-order correlation coefficient (r(s) = 0.57, P < 0.01; median difference = 0, P = 0.50). Strong agreement was shown among the 42 patients who reported income at both visits; 71% reported the same annual income category (kappa = 0.72, 95% CI 0.47-0.96, P < 0.01; r(s) = 0.68, P < 0.01; median difference = 0, P = 0.77). Age, disease severity and duration, previous therapy, self-reported annual income, and medication side-effects were not statistically associated with the reliability of WTP.

CONCLUSIONS

WTP and annual income demonstrated moderate and strong test-retest reliability, respectively. Self-reported WTP can serve as a reliable measure for future health economics research on onychomycosis.

Distribution of toenail dystrophy predicts histologic diagnosis of onychomycosis

BACKGROUND

Onychomycosis (OM) affects up to 10% of the general population and is associated with functional impairment. Clinically, OM can mimic nail psoriasis, trauma, lichen planus, oncyhogryphosis, and other disorders. Laboratory methods for diagnosing OM vary in accuracy and predictive value. Clinical clues to OM would help guide laboratory testing and decrease improper empiric antifungal therapy.

OBJECTIVE

The goal of this study was to determine whether particular distribution patterns of toenail dystrophy are associated with fungal infection of the nail.

METHODS

We retrospectively reviewed toenail clippings submitted over a 5-year period to our pathology department for periodic acid-Schiff (PAS) staining for diagnosis of OM.

RESULTS

Specimens from a total of 311 patients (130 men, 181 women; mean age: 48.3 yrs; range: 19-97 yrs) were included. Overall, 150 specimens (48.2%) were histologically positive for OM. OM was significantly more likely to be diagnosed in men (P < .01), in persons over the age of 64 (P < .02), and in the context of tinea pedis (P < .001). Involvement of the third (41/65; 63.1%) or fifth (27/41; 65.9%) toenails of either foot significantly correlated with OM (P < .025). Dystrophy of the great toenail was seen in 257/311 (82.6%) and was associated with OM in about half of cases (128/257; 49.8%). Dystrophy of first and fifth nails on the same foot was predictive of OM (23/32; P < .01). Unilateral dystrophy correlated positively with OM (79/142; 55.6%; P < .02), with a stronger correlation when 2 or more nails were dystrophic (33/42; P < .001). Dystrophy of the second or fourth nails, a single nail, or all 10 nails did not support or contradict of OM. Female gender was a negative predictor for OM (P < .001).

LIMITATIONS

Potassium hydroxide and culture results were not available to correlate with histology. PAS staining of nail clippings has inherent diagnostic limitations.

CONCLUSIONS

Dystrophy of the third or fifth toenails, of the first and fifth nails on the same foot, unilateral dystrophy, male gender, an age over 64, and the presence of tinea pedis are all independent predictive factors of OM. Presence of these patterns of dystrophy may help to clinically distinguish OM and guide laboratory testing.

Costs and quality of life in patients with moderate to severe plaque-type psoriasis in Germany: A multi-center study

BACKGROUND

This study evaluated costs, disease severity and health-related quality of life (QoL) in patients with moderate to severe plaque-type psoriasis.

PATIENTS AND METHODS

Patients with a 'psoriasis area and severity index' (PASI) > 12 and/or a body surface area (BSA) > 10 were enrolled in dermatological practices and hospital outpatient departments (n = 184) and the total costs of illness generated during the last 12 months were retrospectively calculated. QoL was assessed using the SF-36 and the DLQI. Participants were stratified into three subgroups according to the treatment received during the 1 year documentation period; a) patients without and b) patients with phototherapy or standard systemic therapy, and c) patients who had failed, were intolerant or had contraindications to at least two standard systemic therapies. The study was performed before biologics became available for the treatment of psoriasis in Germany.

RESULTS

Included patients had severe skin symptoms (mean PASI 18.2) and a highly impaired QoL (mean DLQI 10.6). Total annual costs amounted to euro 6,709. Patients belonging to subgroup C had the most severe skin symptoms (mean PASI 22.2), the lowest QoL (mean DLQI 12.6), the highest hospitalization rate and largest loss of productivity. These patients produced the highest total costs of 8.831 euro/y.

CONCLUSIONS

Patients who cannot (or can no longer) be adequately managed with standard treatments are characterized by high disease activity, high costs and reduced QoL. Improved treatment options particularly for these patients are medically necessary and appear economically sensible.

Systemic antifungal agents: an update of established and new therapies

Terbinafine is the drug of choice for dermatophyte onychomycosis. Adjunct therapies, such as topical agents or surgical approaches, may improve outcomes in patients who have risk factors for incomplete response or recurrence. Despite many studies of newer antifungal agents for tinea capitis, griseofulvin (20 mg/kg/d) remains the gold standard. Terbinafine (> or = 6 mg/kg/d) and fluconazole (8 mg/kg once weekly) have yet to demonstrate comparable efficacy in large-scale RCTs. The current role of second-generation triazoles and echinocandins is for treatment of invasive candidiasis and invasive aspergillosis in patients who are critically ill and immunocompromised. Strengths of the newer triazoles include increased activity against resistant and emerging pathogens, convenience of oral formulations, and in vivo activity against subcutaneous mycoses, in particular eumycotic mycetoma. Their metabolism via cytochrome P450 isoenzymes increases the risk for significant drug interactions, and their established mechanism of action may lead to development of resistant pathogens. The echinocandins inhibit fungal cell wall synthesis, a novel therapeutic target; thus, they are effective against azole-resistant species. Their metabolism is independent of hepatic cytochrome P450 enzymes, minimizing drug interactions. They are available only as i.v. formulations.

Onychomycosis in the Elderly

The prevalence of onychomycosis is nearly 20% in patients aged >60 years. In North America, 90% of toenail onychomycosis is caused by dermatophytes (Trichophyton species). Distal-lateral subungual onychomycosis is the most common clinical presentation. The potassium hydroxide test is the most cost-effective diagnostic method. Although nail clipping for histology using periodic acid-Schiff stain is more sensitive, it is much more expensive. Elderly patients have specific risk factors for poor response to therapy for onychomycosis, including frequent nail dystrophy, slow growth of nails and increased prevalence of peripheral vascular disease and diabetes mellitus. Elderly people with diabetes should be treated for onychomycosis to prevent secondary bacterial infections and subsequent complications. Terbinafine is the drug of choice for dermatophyte onychomycosis, with greater mycological cure rates, less serious and fewer drug interactions, and a lower cost than continuous itraconazole therapy. Adjunct debridement may improve the clinical and complete cure rates compared with terbinafine alone. Common adverse effects of terbinafine in the elderly include nausea, sinusitis, arthralgia and hypercholesterolaemia. For onychomycosis caused by Candida or nondermatophyte moulds, there is no superior systemic therapy. In general, topical nail lacquers, amorolfine and ciclopirox are not practical for elderly patients because of the recommended frequency of application, periodic routine debridement of affected nails and long duration of therapy. However, nail lacquers may be a good option as monotherapy for patients with superficial white onychomycosis or in combination with systemic antifungal therapy for patients with predisposing factors for poor response or recurrence.

Toenail onychomycosis: current and future treatment options

Onychomycosis is a common disease affecting as much as 8% of the general population. Treatment of onychomycosis is challenging, complicated by low cure rates and relatively high relapse rates. This paper reviews the efficacy of current oral, topical, and surgical treatment options. Currently, the treatment of choice for toenail onychomycosis is oral terbinafine because of its high efficacy, low relapse rates, and cost-effectiveness. Oral itraconazole or fluconazole could be considered for infections caused by Candida. Topical therapies may be a useful adjunct to these systemic therapies, but are less effective when used alone. More research is needed to determine the best measures for preventing reinfection.

Dystrophic onychomycosis due to Microsporum gypseum

A case of onychomycosis with nail dystrophy due to Microsporum gypseum in a healthy 35-year-old woman is described. The infection had a 2-year history, occurring in the site of a nail trauma sustained in a fall from a horse. Diagnosis was based on mycological examination (direct microscope observation and culture). Clinical and mycological recovery was achieved after local treatment with ciclopiroxolamine nail solution and pulsed systemic terbinafine therapy.