Itraconazole pulse therapy for onychomycosis and dermatomycoses: an overview

Nd:YAG 1064 nm laser treatment for onychomycosis - is it really effective? A prospective assessment for efficiency and factors contributing to response

Onychomycosis is a highly prevalent and persistent nail disorder primarily caused by dermatophytes. The effectiveness of current topical and systemic antifungals is limited by the extent and severity of the infection, patient demographics and health status, hepatic toxicity, drug interactions and low compliance. Laser therapy is a promising modality for safe and cost-effective removal of mycotic nail. This prospective study assessed the performance of a multi-series long-pulsed Nd:YAG 1064 nm regimen (30-40 J/cm2 , 1 Hz) in the treatment of 213 mycotic nails in 31 patients. Pain and discomfort were scored at each treatment session and mycological and clinical cure rates were determined 3 months after the last treatment session. Patients presented with mostly severe (mean SCIO score: 21.9 ± 8.9), T. rubrum-positive (87.1%) infections. Most (61%) had a family history of onychomycosis and a significant proportion had comorbidities, including hypertension (38.7%), hyperlipidemia (35.5%) and/or diabetes (12.9%). Treatment was well tolerated and there were no reports of nail deformity or burns. By 3 months post-treatment, mycological cure was achieved by 4 (12.9%) and visual improvements were noted for 10 (32.3%) patients, including 3 (9.7%) with moderate to significant improvements. Clinical response correlated with baseline SCIO ≤ 20 (OR: 0.9 [0.13-6.52]), family history of onychomycosis (OR: 0.27 [0.04-1.50]) and comorbidities (OR: 0.44 [0.05-3.74]). In conclusion, Nd:YAG 1064 nm laser is safe and effective for the management of mild-to-moderate onychomycosis in diverse populations. Further studies will be necessary to adjust treatment parameters to patient and nail profiles and to determine the impact of combined laser and topical therapies.

Combatting antifungal resistance: Paradigm shift in the diagnosis and management of onychomycosis and dermatomycosis

Antifungal resistance has become prevalent worldwide. Understanding the factors involved in spread of resistance allows the formulation of strategies to slow resistance development and likewise identify solutions for the treatment of highly recalcitrant fungal infections. To investigate the recent explosion of resistant strains, a literature review was performed focusing on four main areas: mechanisms of resistance to antifungal agents, diagnosis of superficial fungal infections, management, and stewardship. The use of traditional diagnostic tools such as culture, KOH analysis and minimum inhibitory concentration values on treatment were investigated and compared to the newer techniques such as molecular methods including whole genome sequencing, and polymerase chain reaction. The management of terbinafine-resistant strains is discussed. We have emphasized the need for antifungal stewardship including increasing surveillance for resistant infection.

Effect of Different Itraconazole Dosing Regimens on Cure Rates, Treatment Duration, Safety, and Relapse Rates in Adult Patients With Tinea Corporis/Cruris: A Randomized Clinical Trial

Importance

With worldwide emergence of recalcitrant and resistant dermatophytosis, itraconazole is increasingly being used as the first-line drug for treatment of tinea corporis/cruris (TCC). Apparent inadequacy with low doses has led to empirical use of higher doses and antifungal combinations.

Objective

To compare cure rates, treatment durations, safety profiles, and relapse rates of itraconazole 100, 200, and 400 mg/d for the treatment of TCC.

Design, Setting, and Participants

This double-blind randomized clinical trial included adult patients with treatment-naive TCC involving at least 5% body surface area. Patients were recruited from the dermatology outpatient department of a tertiary care hospital in New Delhi, India between March 1, 2020, and August 31, 2021.

Interventions

Patients were randomized to 1 of the 3 treatment groups. Biweekly blinded assessments were performed until cure or treatment failure. Posttreatment follow-up of at least 8 weeks was conducted to detect relapses.

Main Outcome and Measures

Cure rates, treatment durations, safety profiles, and relapse rates were assessed. Secondary outcomes included comparison of rapidity of clinical response and cost-effectiveness between groups.

Results

Of the 149 patients assessed, the mean (SD) age was 34.3 (12.2) years, 69 patients (46.4%) were women, and 80 patients (53.6%) were men. The difference in cure rate between the 100- and 200-mg groups was statistically nonsignificant (hazard ratio [HR], 1.44; 95% CI, 0.91-2.30; P = .12), while the difference between the 100- and 400-mg groups (HR, 2.87; 95% CI, 1.78-4.62; P < .001) and between the 200- and 400-mg groups (HR, 1.99; 95% CI, 1.28-3.09; P = .002) was statistically significant. Mean (SD) treatment durations were statistically significantly different between the 100- and 400-mg groups (7.7 [4.7] weeks vs 5.2 [2.6] weeks; P = .03) and between the 200- and 400-mg groups (7.2 [3.8] weeks vs 5.2 [2.6] weeks; P = .004), but the difference between the 100- and 200-mg groups was not statistically significant. A total of 55 patients (47.4%) relapsed after treatment. Relapse rates were comparable across groups. No patient discontinued treatment due to adverse effects. Treatment with the 200-mg dose incurred a 63% higher cost and 400 mg a 120% higher cost over 100 mg in achieving cure.

Conclusions and Relevance

In this randomized clinical trial, high overall efficacy was observed among the 3 itraconazole doses for treatment of TCC, but with prolonged treatment durations and considerable relapse rates. Treatment with the 200- and 100-mg doses did not differ significantly in efficacy or treatment durations, while 400 mg scored over the other 2 on these outcomes. Considerable additional cost is incurred in achieving cure with the 200- and 400-mg doses.

Trial Registration

Clinical Trials Registry of India Identifier: CTRI/2020/03/024326.

Parameters that determine dissolution and efficacy of itraconazole and its relevance to recalcitrant dermatophytoses

INTRODUCTION

Recalcitrant dermatophytoses is on the rise. Though myriad factors contribute to recalcitrance including terbinafine resistance, itraconazole largely remains sensitive. However, there are increasing instances of patients not responding adequately to itraconazole despite low MICs, probably due to issues plaguing the pelletization process, resulting in suboptimal quality. Data on this topic was searched on pubmed using the search items: itraconazole, MIC, MFC, quality, assay, pharmacokinetics, pharmacodynamics, dermatophytoses, and recalcitrance. Areas covered: A detailed analysis of the manufacturing process of itraconazole with emphasis on pelletization and parameters affecting the dissolution and bioavailability is presented. Important formulation factors including drug-polymer ratio, polymer type, coating thickness, bead size, and number are discussed. Also covered is the rationale of dosimetry of itraconazole in dermatophytoses based on the skin pharmacokinetics and MIC of the organism. Expert opinion: The process of pelletization has multiple components aiming to achieve maximum dissolution of the drug. Variations in the process, pellet quality, number, and polymer determine absorption. Morphometric analysis of pellets is a simple method to quantify quality of the drug. Once the process has been standardized, dosimetry depends on the route of secretion and site of infection, accounting for the variation of doses from 100 mg to 400 mg/day.

An exploration of the optimum dosage and number of cycles of itraconazole pulse therapy for severe onychomycosis

Although standard itraconazole pulse therapy is a well-established regimen for toenail onychomycosis, the cure rate for onychomycosis remains low. To evaluate the efficacy and safety of different cycles of itraconazole pulse therapy, determine the optimal dosage and number of cycles for onychomycosis. A total of 90 outpatients of our hospital with onychomycosis were randomised into three treatment groups: (1) standard itraconazole pulse therapy (200 mg twice per day, 1 week each month for three pulses); (2) long-term pulse therapy (200 mg twice per day, 1 week each month for six pulses); (3) low-dose and long-term pulse therapy (200 mg/d, 1 week per month for six pulses) and were followed up for 15 months. Of the initial patients, the trial was completed by 81 patients. The complete cure rates were 32.43% for three cycles and 75% for six cycles (P < .001). For six cycles, despite the administration of half-dose for patients weighing no more than 55 kg, there was no statistical difference in the complete cure rate (P = .862). Long-term therapy is effective and safe for the treatment of toenail onychomycosis. For patients weighing no more than 55 kg, long-term half-dose itraconazole pulse therapy is recommended .

Acral manifestations of fungal infections

Fungal infections, which are named according to the body site involved, can affect any skin area, the fingernails, or the toenails. Numerous fungal agents are responsible for both superficial and deep fungal diseases. Dermatophytes and Candida spp are the most common causative organisms on the surface of the hands, feet, and nails of patients with superficial fungal diseases; however, although deep fungal infections of the skin are less common compared with superficial fungal diseases, their incidence is increasing worldwide due to cross-border travel. Most superficial fungal diseases are diagnosed clinically, but sometimes direct microscopic examination with potassium hydroxide and fungal culture may be necessary for diagnosis, especially in patients suspected of having tinea incognito. In cases of superficial fungal infections except for onychomycosis and tinea incognito, topical treatments are usually sufficient and effective, but systemic treatments may be required in recalcitrant cases. Deep fungal diseases may resemble each other clinically; therefore, the organism must be identified with laboratory methods and should be treated for a long period. We review the most important clinical, diagnostic, and therapeutic aspects of fungal diseases. This paper covers fungal problems encountered both in hospitals and in general practice.

VT-1161 dosed once daily or once weekly exhibits potent efficacy in treatment of dermatophytosis in a guinea pig model

Current therapies used to treat dermatophytoses such as onychomycosis are effective but display room for improvement in efficacy, safety, and convenience of dosing. We report here that the investigational agent VT-1161 displays potent in vitro antifungal activity against dermatophytes, with MIC values in the range of ≤0.016 to 0.5 μg/ml. In pharmacokinetic studies supporting testing in a guinea pig model of dermatophytosis, VT-1161 plasma concentrations following single oral doses were dose proportional and persisted at or above the MIC values for at least 48 h, indicating potential in vivo efficacy with once-daily and possibly once-weekly dosing. Subsequently, in a guinea pig dermatophytosis model utilizing Trichophyton mentagrophytes and at oral doses of 5, 10, or 25 mg/kg of body weight once daily or 70 mg/kg once weekly, VT-1161 was statistically superior to untreated controls in fungal burden reduction (P < 0.001) and improvement in clinical scores (P < 0.001). The efficacy profile of VT-1161 was equivalent to those for doses and regimens of itraconazole and terbinafine except that VT-1161 was superior to itraconazole when each drug was dosed once weekly (P < 0.05). VT-1161 was distributed into skin and hair, with plasma and tissue concentrations in all treatment and regimen groups ranging from 0.8 to 40 μg/ml (or μg/g), at or above the MIC against the isolate used in the model (0.5 μg/ml). These data strongly support the clinical development of VT-1161 for the oral treatment of onychomycosis using either once-daily or once-weekly dosing regimens.

Itraconazole (Sporanox®) in superficial and systemic fungal infections

Itraconazole (Sporanox) is a triazole antifungal agent with a broad activity spectrum and favorable pharmacokinetic and safety profiles. Numerous clinical trials have established the efficacy and safety of itraconazole in the treatment of superficial fungal infections. In this field, full exploitation of its pharmacokinetics in keratinized tissues has led to the development of intermittent (pulse) treatment regimens that allow similar efficacy with lower overall drug exposure as well as a reduction in treatment costs. The additional anti-inflammatory action of itraconazole also makes it suitable for application in difficult-to-treat inflammatory skin disorders, such as seborrheic dermatitis. Recently, a new oral liquid formulation and an intravenous formulation have been developed, extending the therapeutic application of itraconazole to systemic fungal infections. Due to its broad activity spectrum and excellent tolerability, itraconazole is a valuable addition to the antifungal armamentarium used for prophylactic and empiric treatment in immunocompromised hosts.

Two novel itraconazole pulse therapies for onychomycosis: A 2‐year follow‐up

BACKGROUND

Itraconazole given in pulse therapy has become popular for onychomycosis treatment since it results in less plasma exposure to the drug while maintaining an effective drug concentration in the nail plate and also increasing patient compliance.

OBJECTIVE

The current study aims to evaluate two different regimens of itraconazole for toenail onychomycosis, looking at both the immediate post-therapy cure rate and the relapse rate after 2 years.

METHODS

Two groups of 52 patients each were given either 'standard' oral itraconazole pulse therapy for 3 months (200 mg x 2/day for 1 week/month) followed by an additional single course (200 mg/day for 7 days) after 3 months (regimen A) or 'modified' (6-week interval) itraconazole pulse therapy x3 followed by an additional single course (200 mg x 2/day for 7 days) after 3 months. All patients were followed-up for 24 months from the beginning of treatment.

RESULTS

Regimen A: 37 patients were available for examination after 24 months, of whom 22 patients (59.5%) had total cure and two patients (5.5%) had marked improvement. Regimen B: 38 patients were available for examination after 24 months, of whom 29 patients (76.3%) had total cure and three patients (7.9%) had marked improvement. There were no statistical differences in cure rates between the two groups at the end of treatment, after 12 months and after 24 months. None of the patients (in both treatment groups) who had total cure at the end of the treatment period had onychomycosis recurrence after 12 or 24 months.

CONCLUSION

The results at the end of the 24-month period are encouraging, where 64.9% (regimen A) and 84.2% (regimen B) of the patients had total cure or marked improvement in their toenail condition. Therefore, those two regimens are acceptable alternatives to the current treatment regimen.

Onychomycosis caused by Fusarium sp in Sri Lanka: prevalence, clinical features and response to itraconazole pulse therapy in six cases

OBJECTIVES

The aims of our study were to ascertain the proportion of Fusarium onychomycosis among patients with suspected onychomycosis, to record clinical features and to assess the efficacy of itraconazole pulse therapy in treatment.

METHODS

Six patients with positive isolates of Fusarium sp were treated in an open, prospective manner with itraconazole: two pulses for fingernails and three pulses for toenails. Significant growth of Fusarium sp was considered when both microscopy of direct mounts in KOH and culture were positive for mold. Efficacy parameters were mycological cure and clinical cure. Mycological cure was negative direct microscopy (KOH) and culture. Clinical cure was complete absence of signs of onychomycosis.

RESULTS

Prevalence of Fusarium onychomycosis was 6.25% (8/128). Three women and three men were studied. All had bilateral big toenails involved which were of the distal and lateral onychomycosis. Three of them had associated fingernail onychomycosis with periungual inflammation. All our patients were immunocompetent. At month 12 from the start of treatment, mycological cure was 100% while only three out of five patients showed normal nail growth and clinical cure. There were no significant clinical or laboratory adverse effects.

CONCLUSIONS

Our data reconfirmed that Fusarium nail infections are difficult to eradicate. Since the therapeutic reservoir in toenails is 11 months, these patients should be followed up for a total of 12 months before coming to the final conclusion.

The significance of itraconazole for treatment of fungal infections of skin, nails and mucous membranes

Itraconazole is an antifungal drug from the triazole group with distinct in vitro activity against dermatophytes, yeasts and some molds. Itraconazole has a primarily fungistatic activity. Itraconazole accumulates in the stratum corneum and in nail material due to its high affinity to keratin, as well as in sebum and vaginal mucosa. Together with terbinafine and fluconazole, itraconazole belongs to the modern highly effective systemic antifungal drugs with a favorable risk-benefit ratio and for this reason is a preferred therapy option for fungal infections of skin, nails and mucous membranes. Compared to terbinafine in the treatment of fingernail and toenail fungal infections, itraconazole offers the advantage of a broad antifungal spectrum and better effectiveness against onychomycosis caused by yeasts yet appears inferior with regard to the more common dermatophyte infections. Itraconazole constitutes an important therapy option, along with fluconazole, terbinafine, ketoconazole and griseofulvin, for the treatment of dermatophyte infections of glabrous skin (tinea pedis, tinea manuum, tinea corporis and tinea cruris) in adults following unsuccessful topical therapy. In the oral therapy of tinea capitis, itraconazole plays an especially important role, in particular for disease caused by Microsporum canis (for children, however, only off-label use is feasible currently). In the treatment of oropharyngeal candidiasis, candidiasis of the skin and vulvovaginal candidiasis, itraconazole and fluconazole are the preferred treatment options in cases in which topical therapy has proven unsuccessful.

Advances in topical and systemic antifungals

Topical antifungal agents are generally used for the treatment of superficial fungal infections unless the infection is widespread, involves an extensive area, or is resistant to initial therapy. Systemic antifungals are often reserved for the treatment of onychomycosis, tinea capitis, superficial and systemic candidiasis, and prophylaxis and treatment of invasive fungal infections. With the development of resistant fungi strains and the increased incidence of life-threatening invasive fungal infections in immunocompromised patients, some previously effective traditional antifungal agents are subject to limitations including multidrug interactions, severe adverse effects, and their fungistatic mechanism of actions. Several new antifungal agents have demonstrated significant therapeutic benefits and have broadened clinicians' choices in the treatment of superficial and systemic invasive fungal infections.

Onychomycosis: diagnosis and definition of cure

Until now, there has been no agreement on criteria defining resolution of onychomycosis. Most published reports use clinical and mycological cure, which comprises a completely normal-appearing nail plate, and negative nail culture and microscopy results, as the end point for defining success of therapeutic intervention. Reported here is the definition of onychomycosis, which delineates both primary and secondary criteria for diagnosis of onychomycosis and identifies clinical and laboratory parameters to define a resolved fungal nail infection. Onychomycosis cure is defined by the absence of clinical signs or the presence of negative nail culture and/or microscopy results with one or more of the following minor clinical signs: (1) minimal distal subungual hyperkeratosis; and (2) nail-plate thickening. Clinical signs indicative of persistent onychomycosis at the end of the observation period include (1) white/yellow or orange/brown streaks or patches in or beneath the nail plate; and (2) lateral onycholysis with subungual debris. Although nail appearance will usually continue to improve after cessation of therapy, the nails may have a persistent abnormal appearance even in cases where treatment has been effective.

Pulse itraconazole 400 mg daily in the treatment of chromoblastomycosis

Pulse itraconazole is effective in the treatment of chromoblastomycosis caused by Fonsecaea pedrosoi. Six patients, mean 62.3 years (range 45-79), mean duration 103 months (range 4 months to 30 years), were included in this study. F. pedrosoi was the only isolated organism. Four patients (66.7%) were cured by 12 months. Two patients (33.3%) failed to respond fully to treatment; however, one patient whose culture remained positive showed > 50% improvement at the end of study. Data showed that duration and severity were not predictive of treatment response. No side-effects were noted. Treatment should be continued until absence of organisms is proven by histology and tissue culture. Pulse regimen is more economical with better compliance than the conventional continuous 200-400 mg daily regimen, although optimum treatment duration depends on individual cases.

Dermatophytosis: the management of fungal infections

Dermatophytosis is an infection of the hair, skin, or nails caused by a dermatophyte, which is most commonly of the Trichophyton genus and less commonly of the Microsporum or Epidermophyton genera. Tinea capitis, tinea pedis, and onychomycosis are common dermatologic diseases that may result from such an infection. The treatment of fungal infections caused by a dermatophyte has been successful when treated with oral or topical antifungal agents. Terbinafine, itraconazole, and fluconazole are oral antimycotics that are effective in the treatment of superficial mycoses, although, depending on the severity of the infection, a topical antifungal may be sufficient.

Current use of anti-infectives in dermatology

Dermatologic diseases encompass a broad category of pathologic situations. Infection remains a significant aspect of the pathology faced in patient encounters, and it is natural to expect that anti-infectives play a major element in the armamentarium utilized by dermatologists. Aside from the treatment of the classic bacterial and fungal infections, there are now new uses for antiviral agents to help suppress recurrent disease, such as herpes simplex. There is also the novel approach of using anti-infectives, or agents that have been thought to have antimicrobial activity, to treat inflammatory diseases. This review describes anti-infectives, beginning with common antibiotics used to treat bacterial infections. The discussion will then cover the current use of antivirals. Finally, the description of antifungals will be separated, starting with the oral agents and ending with the topical antimycotics. The use of anti-infectives in tropical dermatology has been purposefully left out, and perhaps should be the subject of a separate review. Cutaneous bacterial infections consist chiefly of those microorganisms that colonize the skin, such as species of staphylococcus and streptococcus. Propionibacterium acnes and certain other anaerobes can be involved in folliculitis, pyodermas and in chronic conditions such as hidradenitis suppurativa.

Pharmacotherapy of onychomycosis

Fungal infections of the nails are frequent in some segments of the population. Dermatophytes, yeasts and moulds are potential pathogens. A series of antifungal treatments are available to the clinician, differing by both their mechanistic nature and mode of administration. The pharmacodynamic and pharmacokinetic properties of each antifungal agent are distinct. This review focuses on the characteristics of amorolfine, bifonazole, ciclopirox, fluconazole, griseofulvin, itraconazole, ketoconazole, ravuconazole, R126638 and terbinafine. Single drug treatments and combined therapies are presented. None of the current drug regimens have demonstrated reliable efficacy against all cases of onychomycosis. Treatment failures, relapses and reinfections remain stubborn problems in the management of onychomycosis.

Treatments of tinea pedis

The severity of tinea pedis infection determines the course of treatment required. Mild infections may be resolved using a topical agent. More severe presentations (eg, dermatophytosis complex) may require treatment that eliminates the bacterial and fungal infection. Some topical monotherapies may exhibit both antifungal and antibacterial activity. In other instances, it may be necessary to combine an antifungal agent with an antibacterial agent. If inflammation is present, an agent with known anti-inflammatory action may need to be used. The chronic presentation of tinea pedis (dry type) sometimes does not respond well to topical therapy. In such instances, systemic antifungal therapy is required to ensure that adequate concentrations of the therapeutic agent are present at the site of infection.

Itraconazole versus terbinafine in the management of onychomycosis: an overview

Ever since the introduction of itraconazole and terbinafine in the management of onychomycosis, there has been a revival of interest in the latter. In order to comprehend the intricate emerging scenario, an endeavor has been made to form a distinct outline in the shape of an overview on several of their facets. The review, therefore, envisages forming and facilitating instant decision-making.

Alternate week and combination itraconazole and terbinafine therapy for chromoblastomycosis caused by Fonsecaea pedrosoi in Brazil

Patients with long-standing chromoblastomycosis may respond poorly to standard treatments such as amphotericin B, oral antifungals, surgical measures or thermotherapy. The objective of this study was to determine the potential of alternate week and combination therapy with itraconazole and terbinafine in the treatment of poorly responsive, or non-responsive, chromoblastomycosis. Four patients with longstanding chromoblastomycosis (8-23 years) caused by Fonsecaea pedrosoi had responded poorly to standard therapies including monotherapy with the oral antifungal agents. In order to try and improve the response to oral itraconazole and terbinafine, alternate week or combination therapy with itraconazole and terbinafine was initiated. Bloodwork including complete blood count and liver function tests were performed every 3-8 weeks to ensure patient safety. Reduction or resolution of lesions of chromoblastomycosis was noted with alternate week or combination treatment using oral itraconazole and terbinafine. Three of four patients experienced no clinical side-effects; the third reported mild, transient gastric discomfort which responded to antacids. Bloodwork generally remained within normal limits throughout the entire course of treatment with no clinically significant changes. The combination therapy was considered effective in treating the poorly responsive chromoblastomycosis of all four patients. Some success with alternative week therapy was also noted in one patient. The favorable response and lack of significant adverse effects suggests that these regimens may be an option for some patients with chromoblastomycosis.

Efficacy of itraconazole as a combined continuous/pulse therapy in feline dermatophytosis: preliminary results in nine cases

This study evaluated the efficacy of itraconazole as a combined continuous/pulse therapy for feline dermatophytosis. Nine cats with dermatophytosis caused by Microsporum canis were treated with itraconazole at 10 mg kg(-1) orally once daily for 28 days and then on an alternate week regimen (1 week off, 1 week on) at the same dosage. Cats were re-evaluated by physical examination and fungal culture at days 28, 42, 56 and 70 if necessary. Treatment was stopped when two consecutive negative fungal cultures were obtained. Eight cats were cured after 56 days, with two negative cultures obtained at days 28 and 42. In one case, a positive culture was obtained at day 28, but negative cultures were achieved at days 42 and 56. This protocol appears to be effective in the treatment of feline dermatophytosis, although these preliminary results should be confirmed by a controlled study.

Intermittent low dose itraconazole treatment for onychomycosis--long term follow-up

Eighty-seven patients with toenail onychomycosis were treated with intermittent low-dose itraconazole, 200 mg day(-1) for one week every four weeks; this regimen was repeated six times. A total of 77 patients (88.5%) showed microscopical and cultural cure after 6 months of treatment. A three-year follow-up showed a relapse rate of 6.5% occurring only during the first year after treatment.

Itraconazole pulse therapy for the treatment of Candida onychomycosis

In this open label, multicentre trial, 44 patients with clinical and mycological evidence of Candida onychomycosis were treated with itraconazole pulse therapy. Onychomycosis of the toes alone and concomitant disease involving the fingers and toes was treated with three pulses, and onychomycosis of the fingers alone with two pulses. Final evaluation for patients with finger and toe onychomycosis was at 6-9 months and 9-12 months, respectively. There were 29 patients with toe onychomycosis (C. albicans, 27; C. glabrata, one; Candida species, one), 12 patients with finger onychomycosis (C. albicans, two; C. glabrata, one) and three patients had combined toe and finger onychomycosis (C. albicans, two; C. guillermondii, one). In the patients with toe onychomycosis mycological cure was observed in 29 of 32 patients (90.6%). There was complete cure [mycological cure (negative culture and KOH at endpoint evaluation) with clinical cure] or marked improvement (mycological cure with 75% or greater decrease in area of involvement of target nail compared with pretherapy) in 24 of 32 patients (75.0%). All 12 patients with finger onychomycosis alone due to Candida species achieved a mycological cure (100%). In this group of patients complete cure or marked improvement was observed in 11 of 12 patients (91.7%). Itraconazole pulse therapy was well tolerated and no serious adverse events were reported in the patients treated with this triazole. In conclusion, itraconazole pulse therapy is an effective and safe treatment for both finger and toe onychomycosis associated with Candida.

Single-blind, randomized, prospective study of sequential itraconazole and terbinafine pulse compared with terbinafine pulse for the treatment of toenail onychomycosis

OBJECTIVE

Efficacy and safety of sequential pulse therapy with itraconazole and terbinafine were compared with pulse terbinafine alone in the treatment of toenail onychomycosis.

METHODS

This was a 72-week prospective, single-blind, randomized, multicenter, comparative, parallel group, nonindustry-sponsored trial. A total of 190 patients were recruited from 3 outpatient dermatology offices in North America. Patients were at least 18 years old and had a clinical and mycologic diagnosis of dermatophyte toenail onychomycosis. Patients were randomly assigned to receive sequential pulse therapy (IIT) with 2 pulses of itraconazole followed by 1 or 2 pulses of terbinafine (itraconazole pulse is 200 mg twice daily for 1 week and terbinafine pulse is 250 mg twice daily for 1 week) versus 3 or 4 pulses of terbinafine (TTT). Main outcome measures at week 72 evaluated mycologic cure rate (negative light microscopy and culture), clinical cure (nail appears completely or totally normal), complete cure (clinical and mycologic cure), and effective therapy (mycologic cure and clinical response with at least 5 mm of new, uninvolved nail growth).

RESULTS

At week 72, in the IIT versus TTT groups, the mycologic cure rate was 54 of 75 (72.0%) versus 44 of 90 (48.9%), clinical cure rate was 42 of 75 (56.0%) versus 35 of 90 (38.9%), effective therapy 49 of 75 (65.3%) versus 41 of 90 (45.6%), and complete cure 39 of 75 (52.0%) versus 29 of 90 (32.2%), respectively. Both regimens were well tolerated with no new adverse effects being identified. The rate of permanent discontinuation of therapy because of adverse effects was 2 of 81 (2.5%) with IIT and 2 of 95 (2.1%) with TTT. Each of the adverse effects normalized over time. The number of patients who reported an adverse effect in the 2 groups was 12 of 81 (14.8%) versus 22 of 95 (23.2%), respectively. All these adverse effects were reversible and mild to moderate in severity.

CONCLUSION

Sequential pulse therapy with itraconazole and terbinafine is effective and safe for the treatment of dermatophyte toenail onychomycosis.

Pharmacoeconomic analysis of ciclopirox nail lacquer solution 8% and the new oral antifungal agents used to treat dermatophyte toe onychomycosis in the United States

BACKGROUND

Recently a novel topical nail lacquer, ciclopirox solution 8%, has been approved for the treatment of onychomycosis.

OBJECTIVE

This was undertaken to determine the most cost-effective treatment for the treatment of dermatophyte onychomycosis of the toes in the United States in 2000.

METHODS

The nature of the problem was defined. The drug comparators were ciclopirox nail lacquer, terbinafine, itraconazole (pulse), itraconazole (continuous), fluconazole, and griseofulvin. A decision analytic model that reflected the manner in which pedal tinea unguium is managed was produced. Studies that have evaluated the efficacy of the nail lacquer and the oral antifungal agents for this indication were identified. Appropriate studies were used in a meta-analysis to determine the mycologic and clinical response rates when the drug comparators are used for the treatment for toe dermatophyte onychomycosis. For each drug comparator a cost of regimen analysis was carried out. This is the sum of the drug acquisition cost, the cost of medical management, and the cost of managing adverse effects. Next, the expected cost of management was calculated, disease free days were determined, and a sensitivity analysis was conducted.

RESULTS

For each comparator the meta-analytic average mycologic cure (MC) rate and clinical response (CR) rates were: ciclopirox nail lacquer (MC: 52.6 +/- 4.2%, CR: 52.4 +/- 9.0%), griseofulvin (MC: 41.1 +/- 20.4%, CR: 33.7 +/- 14.1%), itraconazole (continuous) (MC: 66.3 +/- 4.2%, CR: 70.3 +/- 4.2%), itraconazole (pulse) (MC: 70.8 +/- 5.7%, CR: 73.6 +/- 4.6%), terbinafine (MC: 77.2 +/- 4.0%, CR: 75.3 +/- 2.9%), and fluconazole (MC: 65.6 +/- 7.1%, CR: 66.5 +/- 11.7%). The cost of regimen for the drug comparators was: ciclopirox nail lacquer $325.2, griseofulvin $1413.1, itraconazole (continuous) $1410.2, itraconazole (pulse) $811.7, terbinafine $890.1, and fluconazole $966.8. The cost/mycologic cure rate and expected cost/expected symptom free day were, ciclopirox nail lacquer ($618.2, 1.69), griseofulvin $3438.2, 5.3), itraconazole (continuous) ($2126.9, 3.52), itraconazole (pulse) ($1146.4, 2.01), terbinafine ($1153.0, 2.14), and fluconazole ($1473.7, 2.10). The relative cost-effectiveness was ciclopirox nail lacquer 1.00, itraconazole (pulse) 1.19, fluconazole 1.24, terbinafine 1.27, itraconazole (continuous) 2.08, and griseofulvin 3.13. Sensitivity analysis indicated that ciclopirox nail lacquer was a cost effective alternative compared with the oral regimens of terbinafine, itraconazole (continuous), and griseofulvin when clinical response rate was used as the primary efficacy parameter.

CONCLUSION

Ciclopirox nail lacquer solution 8% is a recent addition to the armamentarium of therapies available to the physician and patient for the treatment of onychomycosis. The nail lacquer is a cost effective agent compared with the oral antifungal therapies, terbinafine, itraconazole, fluconazole, and griseofulvin.

Current Management of Onychomycosis and Dermatomycoses

Three newer oral antifungal agents, itraconazole, terbinafine and fluconazole, have revolutionized treatment of superficial mycoses. The tissue pharmacokinetics of itraconazole and terbinafine allow much shorter courses of therapy- with higher efficacy-in the treatment of onychomycosis, compared to other oral agents. Itraconazole pulse dosing and terbinafine daily dosing have shown comparable efficacy against dermatophyte onychomycosis; similar itraconazole regimens have been effective against nondermatophyte infections. Refractory clinical patterns of nail disease appear to be more responsive to oral antifungal therapy when combined with adjunctive therapy, such as debridement. These agents are effective against cutaneous dermatophytosis, with shorter treatment regimens. Tinea versicolor may be treated with a single-dose, intermittent, or daily regimen of an oral azole agent, depending on the drug selected. These newer oral antifungal agents have been proven effective against tinea capitis; effective regimens are shorter than those for griseofulvin. The safety profile of these newer agents has been very favorable.

Onychomycosis in the elderly

Onychomycosis is found more frequently in the elderly, and in more males than females. Onychomycosis of the toes is usually caused by dermatophytes, most commonly Trichophyton rubrum and T. mentagrophytes. The most common clinical presentations are distal and lateral subungual onychomycosis (which usually affects the great/first toe) and white superficial onychomycosis (which generally involves the third/fourth toes). Only about 50% of all abnormal-appearing nails are due to onychomycosis. In the remainder, trauma to the nail, psoriasis and conditions such as lichen planus should be considered in the differential diagnosis. Therefore, the clinical impression of onychomycosis should be confirmed by mycological examination, whenever possible. The management of onychomycosis may include no therapy, palliative treatment with mechanical or chemical debridement, topical antifungal therapy, oral antifungal agents or a combination of treatment modalities. In the US, the only new oral agents approved for treatment of onychomycosis are terbinafine and itraconazole. Fluconazole is approved for onychomycosis in some other countries. Ciclopirox nail lacquer has recently been approved in the US for the treatment of onychomycosis. In some other countries topical agents such as amorolfine are also used. Griseofulvin and ketoconazole are no longer preferred for the treatment of onychomycosis. The new oral antifungal agents are effective and well tolerated in the elderly. Patient selection should be based on the history (including systems review and medication record), examination and baseline monitoring, if indicated. Laboratory monitoring during therapy for onychomycosis varies among physicians. A combination of removal of the diseased nail plate or local measures and oral antifungal therapy may be optimal in certain instances, e.g. when lateral onychomycosis or dermatophytoma are present. For dermatophyte toe onychomycosis the recommended duration of therapy with terbinafine is 250 mg/day for 12 weeks. For itraconazole (pulse) the regimen is 200 mg twice daily for 1 week on, 3 weeks off, repeated for 3 consecutive pulses and with fluconazole the regimen is 150 to 300 mg once weekly given for a usual range of 6 to 12 months or until the nail plate has grown out. In some instances, if extra therapy is required, one suggestion is that 4 weeks of terbinafine or an extra pulse of itraconazole are given between months 6 and 9 from the start of therapy. Once cure has been achieved, it is important to counsel patients on the strategies of reducing recurrence of disease.

Onychomycosis. Treatment, quality of life, and economic issues

Onychomycosis is a public health concern because of its high worldwide incidence and prevalence, and its potential for spread of fungal elements to others, as well as complications such as cellulitis, bacterial infection, pain, and extensive dermatophytic infections. The incidence of onychomycosis has been increasing, particularly in individuals over 60 years of age, patients with HIV infection, and patients with diabetes mellitus. Onychomycosis may impact upon physical, functional, psychosocial, and emotional aspects of life. Difficulty walking, wearing shoes, and embarrassment are common complaints. Quantification of such quality-of-life changes are significant to clinical practice in that many factors can affect overall patient health. In light of the potential clinical implications on physical and mental health, onychomycosis should be considered a medical condition that deserves rigorous clinical management. Onychomycosis can be treated effectively and with comparative safety with the new generation of oral antifungal agents (itraconazole, fluconazole and terbinafine). Significantly improved pharmacokinetic and pharmacodynamic profiles permit markedly reduced duration of administration, individual drug exposure, and ultimately enhanced patient compliance and satisfaction with therapy. In addition, a number of pharmacoeconomic studies have documented the cost effectiveness of these newer agents compared with both traditional pharmacologic treatment and topical therapies. The currency figures quoted are 1997 values. With regard to continuous oral antifungal regimens, terbinafine therapy has been found to be most cost effective in the treatment of toenail onychomycosis, with a drug acquisition cost of $US522.50. However, improved safety, tolerability, efficacy and cost effectiveness have been documented with itraconazole intermittent, pulse regimens. With itraconazole pulse therapy, the drug acquisition cost decreases to $US488.90. Additionally, the total cost of medical management is less for itraconazole therapy compared with that of terbinafine ($US261.00 vs $US306.00). Because sensitivity analyses for itraconazole and terbinafine have been found to be somewhat comparable in terms of mycological cure, clinical response, and relapse rates, other variables such as safety and efficacy profiles, and patient attitudes and expectations toward therapy need to be considered when formulating an onychomycosis pharmacologic treatment plan. The drug aquisition cost of fluconazole given as a 300 mg dose once weekly for 6 months is $US562.76 and given as a 150 mg dose once weekly (for 6 months) $US281.38.

Itraconazole

Itraconazole is a broad spectrum triazole antifungal agent. It has favourable pharmacodynamic and pharmacokinetic profiles and is available as both oral and i.v. formulations. Over the last two decades, clinical and animal infection studies have demonstrated the efficacy of itraconazole in a wide range of superficial fungal infections including difficult-to-treat dermatophytoses and onychomycoses. Furthermore, shortened treatment regimens have proven to be effective, ranging from 1-day treatment for vaginal candidosis to 1-week pulse therapy per month, for 2-4 months, in onychomycosis and follicular dermatophytosis. Clinical experience with itraconazole in the treatment of deep mycoses is less comprehensive. However, results in systemic candidosis, sporotrichosis, blastomycosis, paracoccidioiodomycosis, certain types of histoplasmosis and aspergillosis are extremely encouraging. Itraconazole is less effective in the treatment of chromomycosis and coccidioidomycosis. Nevertheless, considering the refractory nature of these diseases, itraconazole has proven to be a valuable addition to the antifungal drugs currently available for treatment. Itraconazole has been well-tolerated with doses of up to 400 mg/day being generally free of serious adverse effects. However, a potential for drug interactions exists, mediated through the cytochrome P450 enzyme 3A4 system, which should be considered when itraconazole is used as part of a multi-drug regimen.

A risk-benefit assessment of the newer oral antifungal agents used to treat onychomycosis

The newer antifungal agents itraconazole, terbinafine and fluconazole have become available to treat onychomycosis over the last 10 years. During this time period these agents have superseded griseofulvin as the agent of choice for onychomycosis. Unlike griseofulvin, the new agents have a broad spectrum of action that includes dermatophytes, Candida species and nondermatophyte moulds. Each of the 3 oral antifungal agents, terbinafine, itraconazole and fluconazole, is effective against dermatophytes with relatively fewer data being available for the treatment of Candida species and nondermatophyte moulds. Itraconazole is effective against Candida onychomycosis. Terbinafine may be more effective against C. parapsilosis compared with C. albicans; furthermore with Candida species a higher dose of terbinafine or a longer duration of therapy may be required compared with the regimen for dermatophytes. The least amount of experience in treating onychomycosis is with fluconazole. Griseofulvin is not effective against Candida species or the nondermatophyte moulds. The main use of griseo-fulvin currently is to treat tinea capitis. Ketoconazole may be used by some to treat tinea versicolor with the dosage regimens being short and requiring the use of only a few doses. The preferred regimens for the 3 oral antimycotic agents are as follows: itraconazole - pulse therapy with the drug being administered for 1 week with 3 weeks off treatment between successive pulses; terbinafine - continuous once daily therapy; and fluconazole - once weekly treatment. The regimen for the treatment of dermatophyte onychomycosis is: itraconazole - 200mg twice daily for I week per month x 3 pulses; terbinafine - 250 mg/day for 12 weeks; or, fluconazole - 150 mg/wk until the abnormal-appearing nail plate has grown out, typically over a period of 9 to 18 months. For the 3 oral antifungal agents the more common adverse reactions pertain to the following systems, gastrointestinal (for example, nausea, gastrointestinal distress, diarrhoea, abdominal pain), cutaneous eruption, and CNS (for example, headache and malaise). Each of the new antifungal agents is more cost-effective than griseofulvin for the treatment of onychomycosis and is associated with high compliance, in part because of the shorter duration of therapy. The newer antifungal agents are generally well tolerated with drug interactions that are usually predictable.