Mark Ling

Effects of administration of a single dose of a humanized monoclonal antibody to CD11a on the immunobiology and clinical activity of psoriasis

BACKGROUND CD11a/CD18 comprise subunits of leukocyte function associated antigen (LFA-1), a T-cell surface molecule important in T-cell activation, T-cell emigration into skin, and cytotoxic T-cell function. OBJECTIVE We explored the immunobiologic and clinical effects of treating moderate to severe psoriasis vulgaris with a single dose of humanized monoclonal antibody against CD11a (hu1124). METHODS This was an open label study with a single dose of hu1124 at doses of 0.03 to 10 mg/kg. Clinical (Psoriasis Area and Severity Index [PASI]) and immunohistologic parameters (epidermal thickness, epidermal and dermal T-cell numbers, and keratinocyte intercellular adhesion molecule 1 [ICAM-1] expression) were followed. RESULTS Treatment with hu1124, at doses higher than 1.0 mg/kg (group III), completely blocks CD11a staining for at least 14 days in both blood and psoriatic plaques. At 0.3 to 1.0 mg/kg, T-cell CD11a staining was completely blocked; however, blockade lasted less than 2 weeks (group II). Only partial saturation of either blood or plaque cellular CD11a was observed at doses of hu1124 between 0.01 and 0.1 mg/kg (group I). This pharmacodynamic response was accompanied by decreased numbers of epidermal and dermal CD3(+) T cells, decreased keratinocyte and blood vessel expression of ICAM-1, and epidermal thinning. Statistically significant drops in PASI compared with baseline were observed in group II patients at weeks 3 and 4 and in group III patients at weeks 2 through 10. No significant drop in PASI score was observed in group 1. Adverse events were mild at doses of 0.3 mg/kg or less and included mild chills, abdominal discomfort, headache, and fever. At a single dose of 0.6 mg/kg or higher, headache was the most common dose-limiting toxicity observed. CONCLUSION Targeting CD11a may improve psoriasis by inhibiting T-cell activation, T-cell emigration into the skin, and cytotoxic T-cell function.

Once-weekly fluconazole (150, 300, or 450 mg) in the treatment of distal subungual onychomycosis of the fingernail.

BACKGROUND Onychomycosis is a prevalent infection of the nail caused primarily by dermatophytes. Fluconazole is active in vitro against the most common pathogens of onychomycosis, penetrates into the nail bed, and is clinically effective in the treatment of a wide variety of superficial fungal infections. OBJECTIVE The purpose of this study was to compare the efficacy and safety of three different doses of fluconazole (150, 300, and 450 mg) given orally once weekly to that of placebo in the treatment of distal subungual onychomycosis of the toenail caused by dermatophytes. METHODS In this multicenter, double-blind study, 362 patients with mycologically confirmed onychomycosis were randomized to treatment with fluconazole, 150, 300, or 450 mg once weekly, or placebo once weekly for a maximum of 12 months. To enter the study, patients were required to have at least 25% involvement of the target nail with at least 2 mm of healthy nail from the nail fold to the proximal onychomycotic border. Patients who were clinically cured or improved at the end of treatment were further evaluated over a 6 month follow-up period. At both the end of therapy and the end of follow-up, clinical success of the target nail was defined as reduction of the affected area to less than 25% or cure. RESULTS At the end of therapy, 86% to 89% of patients in the fluconazole treatment groups were judged clinical successes as defined above compared with 8% of placebo-treated patients. Clinical cure (completely healthy nail) was achieved in 28% to 36% of fluconazole-treated patients compared with 3% of placebo-treated patients. Fluconazole demonstrated mycologic eradication rates of 47% to 62% at the end of therapy compared with 14% for placebo. The rates at the end of follow-up were very similar, indicating that eradication of the dermatophyte was maintained over the 6-month period. All efficacy measures for the fluconazole groups were significantly superior to placebo (p=0.0001); there were no significant differences between the fluconazole groups on these efficacy measures. The clinical relapse rate among cured patients over 6 months of follow-up was low at 4%. Fluconazole was well tolerated at all doses over the 12-month treatment period, with the incidence and severity of adverse events being similar between the fluconazole and placebo treatment groups. Mean time to clinical success in the fluconazole treatment groups was 6 to 7 months. This time frame may be used as a guideline for fluconazole treatment duration. CONCLUSION The results of this study support the use of fluconazole in the treatment of distal subungual onychomycosis of the toenail caused by dermatophytes. Doses between 150 to 450 mg weekly for 6 months were clinically and mycologically effective as well as safe and well tolerated.

Randomized, double-blind, double-dummy, vehicle-controlled study of ingenol mebutate gel 0.025% and 0.05% for actinic keratosis

BACKGROUND There is a need for improved medical approaches to the treatment of actinic keratosis. Ingenol mebutate, a diterpene ester extracted and purified from the plant Euphorbia peplus, is being evaluated as a topical therapy for actinic keratosis. OBJECTIVE Assess the efficacy and safety of ingenol mebutate (formerly PEP005) gel at 3 dosing regimens for the treatment of actinic keratosis. METHODS Patients with non-facial actinic keratoses applied vehicle gel for 3 days, ingenol mebutate gel, 0.025% for 3 days, or ingenol mebutate gel, 0.05% for 2 or 3 days, with an 8-week follow-up period. RESULTS All 3 active treatments were significantly more effective than vehicle at clearing actinic keratosis lesions, with a dose response observed. The partial clearance rate (primary efficacy end point) for patients treated with ingenol mebutate gel ranged from 56.0% to 75.4% compared with 21.7% for vehicle gel (P = .0002 to P < .0001 vs vehicle). The complete clearance rate was also significantly higher (P < or = .0006) for patients in the ingenol mebutate gel treatment groups (range: 40.0% to 54.4%) compared with vehicle (11.7%), as was the baseline clearance rate (range: 42.0% to 57.9% for ingenol mebutate gel compared with 13.3% for vehicle, P < .0001 to .0007 vs vehicle). The median percentage reduction in baseline actinic keratosis lesions for patients treated with ingenol mebutate gel ranged from 75% to 100% compared with 0% for vehicle gel (P < .0001 vs vehicle). Active treatment was well tolerated at all dosages. The mechanism of action of this agent is the localized induction of necrosis followed by a transient inflammatory response, and this was manifested in most patients as transient local skin responses consisting primarily of erythema, flaking/scaling, and crusting. There was no evidence of treatment-related scarring. LIMITATIONS Local skin responses may have suggested active treatment to investigators. CONCLUSIONS Short-course, field-directed therapy with ingenol mebutate gel for actinic keratoses on non-facial sites seems to be effective with a favorable safety profile and potential benefits over topical agents that require a more prolonged course of treatment.

Tazarotene 0.1% gel plus corticosteroid cream in the treatment of plaque psoriasis.

Abstract Background: Topical corticosteroids are often used in the treatment of psoriasis, but long-term use may be associated with serious adverse events such as tachyphylaxis or atrophy of the skin. Tazarotene, a new topical retinoid, has demonstrated significant clinical benefits but can cause mild to moderate local irritation. Objective: We evaluate whether a combination treatment of topical tazarotene and a topical corticosteroid would increase efficacy while reducing the incidence of local adverse events associated with a topical retinoid. Methods: Three hundred patients enrolled in an investigator-masked study were randomly assigned to 1 of 4 treatment groups: tazarotene 0.1% gel in combination with placebo cream, or with a low-, mid-, or high-potency corticosteroid cream, for 12 weeks of treatment and a posttreatment follow-up at week 16. Results: Tazarotene 0.1% gel in combination with a mid- or high-potency corticosteroid, when compared with tazarotene plus placebo cream, achieved significantly greater reductions in scaling, erythema, and overall lesional severity, and a decreased incidence of adverse events. Conclusion: All tazarotene combinations (including tazarotene plus placebo) were highly effective in rapidly reducing the severity of psoriasis. Combining tazarotene with a topical corticosteroid increased efficacy while reducing the incidence of local adverse events. (J Am Acad Dermatol 1998;39:590-6.)

Acitretin: Optimal dosing strategies

Acitretin is an oral synthetic retinoid effective in the treatment of psoriasis. As monotherapy, acitretin has been shown to be most effective in treating pustular and erythrodermic types of the disease. Monotherapy with acitretin for plaque-type psoriasis is often less successful; however, its use in combination with other therapies is highly effective in treating this form of the disease. Dose-response studies have established the effective dose range of acitretin as well as the dose-dependence of its side effects. Because both efficacy and side effects can vary substantially among individual patients, proper dosing of acitretin requires a balance between optimizing response and minimizing toxicity for each patient. Optimal dosing for individual patients may be achieved through a dose-escalation strategy involving initiation of therapy at low doses (10 to 25 mg/day) and, if necessary, gradually increasing the dose as tolerated until optimal response is achieved.

Once-weekly fluconazole (450 mg) for 4, 6, or 9 months of treatment for distal subungual onychomycosis of the toenail

BACKGROUND Fluconazole is a bis-triazole antifungal agent approved for the treatment of oropharyngeal, esophageal, and vaginal candidiasis, serious systemic candidal infections, and cryptococcal meningitis. OBJECTIVE The purpose of this study was to evaluate three different durations of once-weekly fluconazole for the treatment of onychomycosis of the toenail caused by dermatophytes. METHODS In a multicenter, randomized, double-blind, parallel, placebo-controlled trial, 384 patients with distal subungual onychomycosis of the toenail received fluconazole, 450 mg once weekly, or placebo for 4, 6, or 9 months. For inclusion, patients were required to have mycologically confirmed distal subungual onychomycosis of the toenail with a large toenail at least 25% clinically affected but having at least 2 mm of healthy nail between the nail fold and the proximal onychomycotic border. Efficacy was assessed by clinical and mycologic (microscopic and microbiologic) measures at screening, at every treatment visit starting at month 3, and at months 2, 4, and 6 after therapy. Observed or volunteered adverse events were recorded and classified at all visits. RESULTS At the end of treatment, very significantly superior clinical and mycologic results were achieved in all fluconazole groups compared with placebo (p=0.0001). This superiority was largely maintained over 6 months of follow-up. The clinical and mycologic responses of the 9-month treatment duration were significantly superior to the 4- and 6-month durations. Similar percentages of patients in the fluconazole and placebo groups reported adverse experiences for all three durations of the study. CONCLUSION Results of this study support the efficacy and safety of fluconazole in the treatment of distal subungual onychomycosis of the toenail.

A randomized study of the safety, absorption and efficacy of pimecrolimus cream 1% applied twice or four times daily in patients with atopic dermatitis

Background: Pimecrolimus cream 1% (Elidel®), a non‐steroid inhibitor of inflammatory cytokines, is effective in the treatment of atopic dermatitis, without corticosteroid‐related side effects such as skin atrophy. It is indicated for twice‐daily application. More frequent applications might be expected either to enhance efficacy or increase toxicity. This study compared the safety, efficacy and systemic absorption of pimecrolimus administered twice daily (recommended dose) and four times daily early in the treatment of patients with moderate to severe atopic dermatitis. Methods: Adolescent and adult patients with moderate to severe atopic dermatitis were randomly assigned to a twice daily (BID) treatment group (n = 24) or a four times daily (QID) group (n = 25). During days 1–7, patients in the QID group applied pimecrolimus four times daily, and patients in the BID group applied pimecrolimus twice daily plus vehicle equivalent twice daily. During days 8–21, all patients were required to use pimecrolimus twice daily and had the option to use up to two further daily treatments (pimecrolimus in the QID group and vehicle equivalent in the BID group). Blood sampling occurred 2, 4, and 6 hours after the first morning application on days 1 and 5 and then prior to the first morning application on days 8 and 15, and any time on day 22. Results: Only 3 (12%) QID patients and 4 (17%) BID patients reported adverse events (primarily mild, transient application‐site burning) with no significant difference between treatment groups in the frequency, type, or severity of adverse events. The median daily number of applications in the QID group during days 8–21 when two additional doses were optional remained at four. Pimecrolimus blood levels from a subgroup of 22 patients showed no difference in systemic exposure between the two dosing regimens. All but three (one in the QID group, two in the BID group) patients had blood levels below the limit of quantification; the highest single blood level of pimecrolimus measured in any patient was 1.37 ng/ml (QID group). Both the QID and BID regimens improved the signs and symptoms of atopic dermatitis similarly as measured by improvements in pruritus severity score, Investigators Global Assessment, Eczema Area and Severity Index, percentage of body surface area affected, and patients self‐assessment of disease control. Conclusions: The data suggest that increasing pimecrolimus application from twice daily to four times daily to treat moderate to severe atopic dermatitis for up to 3 weeks does not alter the safety profile nor does it increase the efficacy of treatment. Systemic absorption of pimecrolimus applied BID and QID is minimal and is not different between dosing regimens. Patients and physicians familiar with the potential hazards of overuse of topical corticosteroids should be reassured that if pimecrolimus is applied at twice the recommended BID dose for short periods of time, there is no effect on safety, tolerability, or systemic absorption.

Pharmacokinetics of three once-weekly dosages of fluconazole (150, 300, or 450 mg) in distal subungual onychomycosis of the fingernail ☆ ☆☆

BACKGROUND Fluconazole has proven to be safe and effective for a variety of superficial and systemic fungal infections. Preliminary analysis of extensive Phase III studies suggests that it is very effective for the treatment of onychomycosis. Its pharmacokinetic properties, including low molecular weight and high water-solubility, suggest a unique ability to penetrate the nail. This feature is likely to account in part for fluconazoles effectiveness in the treatment of onychomycosis. OBJECTIVE Determinations of plasma and fingernail concentrations of fluconazole were performed as part of a larger study comparing the safety and efficacy of once-weekly fluconazole (150, 300, and 450 mg) to placebo in the treatment of distal subungual onychomycosis of the fingernails caused by dermatophytes. The relationship between fluconazole concentrations and efficacy was also examined. METHODS Pharmacokinetic studies were performed by means of plasma and fingernail samples from 133 patients, a subset of 349 patients participating in a double-blind, placebo-controlled clinical trial of fluconazole administered in once-weekly doses of 150, 300, or 450 mg until cure of onychomycosis or for a maximum of 9 months. Blood and fingernail samples for pharmacokinetic analysis were taken at baseline, at week 2, and at monthly intervals during the treatment phase of the study. Patients considered clinically cured or improved also participated in a 6-month follow-up study. During this phase, patients were monitored and samples taken every 2 months. RESULTS Significant amounts of fluconazole were detected in the earliest fingernail samples taken (after 2 weeks of treatment). After two weekly doses, 30% to 33% of steady-state concentrations had been achieved in healthy nails and 22% to 29% in affected nails. Steady state was achieved in 3 to 5 months. Fluconazole concentration in nails as well as plasma followed dose-proportional pharmacokinetics. Nail:plasma ratios in affected nails were 0.4 to 0.6 at 2 weeks and 1.7 to 1.8 at 6 months. Fluconazole concentrations fell slowly after drug discontinuation and were still detectable 4 months after end of treatment. A statistically significant correlation was found between steady-state concentration and clinical and global outcomes. CONCLUSION Fluconazole rapidly penetrates the fingernail, where it is retained at detectable levels for at least 4 months after drug discontinuation. A significant correlation exists between fluconazole concentration in the fingernails and clinical and global outcomes.

Therapy of genital human papillomavirus infections. Part I: Indications for and justification of therapy

Genital human papillomavirus (HPV) infections are an increasingly important subject for physicians treating mucocutaneous diseases. Explosive progress in molecular biology has deepened our understanding of HPV, while simultaneously introducing confusion into the management of these infections: what was dogma just a few years ago is often now fallacy. As a result, the clinical practitioner is confronted with a maze of choices with little consensus to guide him/herself. Perhaps the only reliable rule is that todays opinions will be disproved in the future. Nevertheless, it is important to review the available information carefully and critically. A detailed discussion of the biology, epidemiology, clinical manifestations, and diagnosis of HPV infection will be discussed in part II of this review (in press). In this series of two articles, I will concentrate on the rationale behind treatment of HPV infection, followed by a detailed assessment of the methods available to treat such infections.