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D K Chalker

Publications and source records attributed to D K Chalker.

At least 19 recordsLinked to original sources
PubMed2001

A randomized trial of the efficacy of a new micronized formulation versus a standard formulation of isotretinoin in patients with severe recalcitrant nodular acne.

BACKGROUND: Isotretinoin is very frequently the drug of choice for the management of severe recalcitrant nodular acne. Recently, a new micronized and more bioavailable formulation of isotretinoin has been developed that permits once-daily administration in lower doses than usually used with standard isotretinoin (Accutane), regardless of whether it is taken with or without food. OBJECTIVE: Our purpose was to determine whether micronized isotretinoin and standard isotretinoin are clinically equivalent. METHODS: In this multicenter, double-blind, double-dummy study, 600 patients with severe recalcitrant nodular acne were treated with either 0.4 mg/kg of micronized isotretinoin once daily without food (n = 300) or 1.0 mg/kg per day of standard isotretinoin in two divided doses with food (n = 300). Lesion counts were monitored over 20 weeks. RESULTS: Both treatment groups in this well-controlled clinical trial experienced an equivalent reduction in the number of total nodules (facial plus truncal). In addition, an equivalent proportion of patients achieved 90% clearance of the total number of nodules. Both formulations had similar results for other efficacy variables. CONCLUSION: Once-daily use of the micronized and more bioavailable formulation of isotretinoin under fasted conditions is clinically equivalent to the standard twice-daily formulation under fed conditions in the treatment of severe recalcitrant nodular acne.

Acne Vulgaris↗
PubMed2001

Safety of a new micronized formulation of isotretinoin in patients with severe recalcitrant nodular acne: A randomized trial comparing micronized isotretinoin with standard isotretinoin.

BACKGROUND: Isotretinoin is a very effective drug for treating severe recalcitrant nodular acne. A new micronized formulation of isotretinoin has been shown to be clinically equivalent to standard isotretinoin with improved bioavailability and minimal food effect. The safety profile of the micronized formulation has not been described previously. OBJECTIVE: The objective of this article is to report the incidence and intensity of adverse events found in a comparative, double-blind efficacy study that showed clinical equivalence of the new micronized formulation of isotretinoin and the standard isotretinoin formulation (Accutane). METHODS: Six hundred patients with severe recalcitrant nodular acne were treated with micronized isotretinoin (n = 300) under fasted conditions or standard isotretinoin (n = 300) under fed conditions. One cohort received single daily doses of 0.4 mg/kg of micronized isotretinoin without food and the other cohort received 1.0 mg/kg per day of standard isotretinoin in two divided doses with food. Adverse events were monitored during 20 weeks of drug therapy. RESULTS: The proportion of adverse events in most body systems was generally lower in patients receiving micronized isotretinoin than in those receiving standard isotretinoin. CONCLUSION: Micronized isotretinoin appears to have a safety profile similar to that of standard isotretinoin and to carry a lower risk of mucocutaneous events and hypertriglyceridemia.

Acne Vulgaris↗
PubMed1999

Tazarotene gel is safe and effective in the treatment of acne vulgaris: a multicenter, double-blind, vehicle-controlled study.

Retinoids reverse the abnormal pattern of keratinization seen in acne vulgaris. Tazarotene is the first of a novel family of topical receptor-selective acetylenic retinoids. This study evaluates the safety and efficacy of topical tazarotene 0.1% and 0.05% gels, in comparison to vehicle gel, applied once daily for 12 weeks, in the treatment of mild-to-moderate facial acne vulgaris. A total of 446 patients with facial acne vulgaris were enrolled, and 375 patients, ranging in age from 14 to 44 years, were evaluable in this multicenter, double-blind, randomized study. In comparison to vehicle gel, treatment with tazarotene 0.1% gel resulted in significantly greater reductions in noninflammatory and total lesion counts at all follow-up visits, and inflammatory lesion counts at Week 12. Tazarotene 0.05% gel resulted in significantly greater reductions in noninflammatory and total lesion counts than vehicle gel at Weeks 8 and 12. At Week 12, treatment success rates were 68% and 51% for tazarotene 0.1% and 0.05%, respectively (40% for vehicle gel). Tazarotene gel was an effective, safe, and generally well-tolerated therapy for the treatment of acne vulgaris.

Acne Vulgaris↗
PubMed1997

Clinical efficacy and safety comparison of adapalene gel and tretinoin gel in the treatment of acne vulgaris: Europe and U.S. multicenter trials.

BACKGROUND: Adapalene is a new chemical entity that exhibits tretinoin-like activities in the terminal differentiation process. OBJECTIVE: We evaluated a dose range effect of two concentrations of adapalene gel as acne treatment and compared adapalene 0.1% gel with tretinoin 0.025% gel in the treatment of acne patients in two large multicenter studies. METHODS: Multicenter, investigator-masked, parallel group studies including 89 acne patients in the dose range study and 591 patients in the concurrent controlled studies were conducted. RESULTS: Adapalene gel 0.1% was significantly more effective in treating acne lesions than 0.03% adapalene gel. Adapalene gel 0.1% was significantly more effective than 0.025% or tretinoin gel in one study and of the same effectiveness in the other study. Adapalene gel was always better tolerated than tretinoin gel. CONCLUSION: Adapalene 0.1% gel is a safe and effective treatment of acne vulgaris.

Adapalene↗
PubMed1997

Treatment of acne with a combination clindamycin/benzoyl peroxide gel compared with clindamycin gel, benzoyl peroxide gel and vehicle gel: combined results of two double-blind investigations.

BACKGROUND: It has previously been shown that a combination of erythromycin and benzoyl peroxide is superior to either ingredient when used alone in the treatment of acne. A clindamycin/benzoyl peroxide combination gel might have an advantage over erythromycin/benzoyl peroxide gel because the former does not require refrigeration after it is dispensed. OBJECTIVE: Our purpose was to determine the efficacy and safety of a combination clindamycin/benzoyl peroxide gel when compared with benzoyl peroxide, clindamycin, or vehicle gels. METHODS: In two double-blind, randomized, parallel, vehicle-controlled trials, patients were treated for 11 weeks with once-nightly application of one of the above preparations. Evaluations were performed at 2, 5, 8, and 11 weeks and included lesion counts and assessment of global responses and irritant effects. RESULTS: A total of 334 patients completed the study. All three active preparations were significantly superior to the vehicle in global improvement and in reducing inflammatory lesions and noninflammatory lesions. The combination gel was significantly superior to the two individual agents in global improvement and reduction of inflammatory lesions and also to the clindamycin gel in reducing noninflammatory lesions. There was no significant difference in tolerance to the active gels versus the vehicle gel. CONCLUSION: In the treatment of acne, topical clindamycin/benzoyl peroxide combination gel is well tolerated and superior to either individual ingredient.

Acne Vulgaris↗
PubMed1996

Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. Nutritional Prevention of Cancer Study Group.

OBJECTIVE: To determine whether a nutritional supplement of selenium will decrease the incidence of cancer. DESIGN: A multicenter, double-blind, randomized, placebo-controlled cancer prevention trial. SETTING: Seven dermatology clinics in the eastern United States. PATIENTS: A total of 1312 patients (mean age, 63 years; range, 18-80 years) with a history of basal cell or squamous cell carcinomas of the skin were randomized from 1983 through 1991. Patients were treated for a mean (SD) of 4.5 (2.8) years and had a total follow-up of 6.4 (2.0) years. INTERVENTIONS: Oral administration of 200 microg of selenium per day or placebo. MAIN OUTCOME MEASURES: The primary end points for the trial were the incidences of basal and squamous cell carcinomas of the skin. The secondary end points, established in 1990, were all-cause mortality and total cancer mortality, total cancer incidence, and the incidences of lung, prostate, and colorectal cancers. RESULTS: After a total follow-up of 8271 person-years, selenium treatment did not significantly affect the incidence of basal cell or squamous cell skin cancer. There were 377 new cases of basal cell skin cancer among patients in the selenium group and 350 cases among the control group (relative risk [RR], 1.10; 95% confidence interval [CI], 0.95-1.28), and 218 new squamous cell skin cancers in the selenium group and 190 cases among the controls (RR, 1.14; 95% CI, 0.93-1.39). Analysis of secondary end points revealed that, compared with controls, patients treated with selenium had a nonsignificant reduction in all-cause mortality (108 deaths in the selenium group and 129 deaths in the control group [RR; 0.83; 95% CI, 0.63-1.08]) and significant reductions in total cancer mortality (29 deaths in the selenium treatment group and 57 deaths in controls [RR, 0.50; 95% CI, 0.31-0.80]), total cancer incidence (77 cancers in the selenium group and 119 in controls [RR, 0.63; 95% CI, 0.47-0.85]), and incidences of lung, colorectal, and prostate cancers. Primarily because of the apparent reductions in total cancer mortality and total cancer incidence in the selenium group, the blinded phase of the trial was stopped early. No cases of selenium toxicity occurred. CONCLUSIONS: Selenium treatment did not protect against development of basal or squamous cell carcinomas of the skin. However, results from secondary end-point analyses support the hypothesis that supplemental selenium may reduce the incidence of, and mortality from, carcinomas of several sites. These effects of selenium require confirmation in an independent trial of appropriate design before new public health recommendations regarding selenium supplementation can be made

Adult↗
PubMed1996

A comparison of the efficacy and safety of adapalene gel 0.1% and tretinoin gel 0.025% in the treatment of acne vulgaris: a multicenter trial.

BACKGROUND: Adapalene is a new synthetic retinoid analogue developed for the topical treatment of acne vulgaris. OBJECTIVE: The study was designed to compare the efficacy and safety and adapalene gel 0.1% with tretinoin gel 0.025% in the treatment of grade II to II facial acne vulgaris. METHODS: Three hundred twenty-three patients were enrolled in this investigator-masked, randomized, parallel group, multicenter trial. Patients applied the test materials to the entire facial area daily, for a period of 12 weeks. Efficacy and cutaneous tolerance were assessed at baseline and weeks 2,4,8, and 12. Efficacy was determined by investigator counts of noninflammatory open and closed comedones, and inflammatory papules and pustules, as well as global improvement. Cutaneous tolerance was evaluated by erythema, scaling, and dryness, along with burning and pruritus. RESULTS: Staring at weeks 2 and 4, adapalene gel produced numerically greater lesion reductions than did tretinoin gel for all lesion types. At week 12, the mean percent reduction in the different lesion counts was as follow: 49% versus 37% for total lesions (p<0.01); 46% versus 33% for noninflammatory lesions (p=0.02); 48% versus 38% for inflammatory lesions (p=0.06) in adapalene and tretinoin gel treatment groups, respectively. Cutaneous side effects were limited to a mild "retinoid dermatitis" occurring in both treatment groups; however, patients treated with adapalene gel tolerated this therapy significantly better than those treated with tretinoin gel. Laboratory test evaluations (hematology, blood chemistries, urinalysis) were performed in 54 patients before and after 3 months of treatment. No clinically significant changes were observed. CONCLUSION: Adapalene gel 0.1% applied once daily was significantly more effective in reducing acne lesions and was better tolerated than tretinoin gel 0.025% in the treatment of acne vulgaris.

Acne Vulgaris↗
PubMed1995

Topical nicotinamide compared with clindamycin gel in the treatment of inflammatory acne vulgaris.

BACKGROUND: Systemic and topical antimicrobials are effective in the treatment of inflammatory acne vulgaris; however, widespread use of these agents is becoming increasingly associated with the emergence of resistant pathogens raising concerns about microorganism resistance and highlighting the need for alternative nonantimicrobial agents for the treatment of acne. Nicotinamide gel provides potent antiinflammatory activity without the risk of inducing bacterial resistance. METHODS: In our double-blind investigation, the safety and efficacy of topically applied 4% nicotinamide gel was compared to 1% clindamycin gel for the treatment of moderate inflammatory acne vulgaris. Seventy-six patients were randomly assigned to apply either 4% nicotinamide gel (n = 38) or 1% clindamycin gel (n = 38) twice daily for 8 weeks. Efficacy was evaluated at 4 and 8 weeks using a Physician's Global Evaluation, Acne Lesion Counts, and an Acne Severity Rating. RESULTS: After 8 weeks, both treatments produced comparable (P = 0.19) beneficial results in the Physician's Global Evaluation of Inflammatory Acne; 82% of the patients treated with nicotinamide gel and 68% treated with clindamycin gel were improved. Both treatments produced statistically similar reductions in acne lesions (papules/pustules; -60%, nicotinamide vs. -43%, clindamycin, P = 0.168), and acne severity (-52% nicotinamide group vs. -38% clindamycin group, P = 0.161). CONCLUSIONS: These data demonstrate that 4% nicotinamide gel is of comparable efficacy to 1% clindamycin gel in the treatment of acne vulgaris. Because topical clindamycin, like other antimicrobials, is associated with emergence of resistant microorganisms, nicotinamide gel is a desirable alternative treatment for acne vulgaris.

Acne Vulgaris↗
PubMed1990

Acne fulminans.

The pathogenesis of acne fulminans remains obscure despite extensive investigations discussed in this review, but evidence points toward an immune mediated phenomenon (eg, hypergammaglobulinemia, depressed complement, circulating immune complexes, hematuria, lytic bone lesions, or inflammatory myositis). Whether acne fulminans begins as an autoimmune process de novo, or whether the process is somehow triggered by minimal inflammation in susceptible individuals remains to be elucidated. Acne fulminans is a rare, disfiguring, and disabling disease. It is associated with many problems, including abnormalities revealed in the laboratory or on roentgenogram. We have reviewed past and present therapies. In conclusion, we emphasize the importance of early diagnosis and treatment to decrease the significant morbidity of acne fulminans.

Acne Vulgaris↗
PubMed1989

The use of live pigs in the surgical training of dermatology residents.

Refining of surgical skills requires instruction, manual repetition, and observation of results. This study demonstrates that while many dermatology residents use pig's feet or synthetic models of skin for practice, few use live animals. We describe the benefits and mechanics of utilizing anesthetized pigs for cutaneous surgical training.

Animals↗
PubMed1987

Efficacy of topical isotretinoin 0.05% gel in acne vulgaris: results of a multicenter, double-blind investigation.

Two hundred sixty-eight patients with mild to moderate acne vulgaris completed a multicenter, double-blind, controlled study comparing isotretinoin 0.05% gel with its vehicle. Patients were treated twice daily for up to 14 weeks. Efficacy was measured by counting facial inflammatory and noninflammatory lesions and by grading acne severity initially and at 2- to 3-week intervals throughout the study. The isotretinoin 0.05% gel proved to be statistically more effective than vehicle in reducing inflammatory lesions after 5 weeks and in reducing noninflammatory lesions and acne severity grade after 8 weeks. Except for two patients who dropped out because of irritation, isotretinoin 0.05% gel was well tolerated.

Acne Vulgaris↗
PubMed1987

Use of gloves among dermatologists.

Despite evidence that rubber or latex surgeon's gloves appear to prevent or reduce the transmission of hepatitis B virus, physicians continue to perform surgical procedures without wearing gloves. Surveys regarding glove usage among members of the American Academy of Dermatology revealed that a majority of those responding do not regularly wear gloves while performing basic dermatologic procedures, such as shave and punch biopsies and curettage and desiccation. Others are still not wearing gloves regularly while performing excisional surgery, hair transplants, and dermabrasion procedures.

Dermatologic Surgical Procedures↗
PubMed1987

Hyperkeratosis lenticularis perstans (Flegel's disease). Case report and literature review.

A case of Flegel's disease, or hyperkeratosis lenticularis perstans, is reported. This rare chronic disorder is characterized by asymptomatic hyperkeratotic papules, usually located on the lower extremities. Most reported cases have been from Europe. We report a case of hyperkeratosis lenticularis perstans from our institution that was treated successfully with topical 5-fluorouracil.

Administration, Cutaneous↗
PubMed1985

An evaluation of a 2% erythromycin ointment in the topical therapy of acne vulgaris.

Two hundred eight patients completed a 12-week, multicenter, double-blind, controlled study comparing a 2% erythromycin ointment to its vehicle. Patients were evaluated by inflammatory lesion counts and Cook acne severity grade at the initial visit and at weeks 2, 4, 8, 10, and 12. The 2% erythromycin ointment proved to be statistically more effective than the vehicle in reducing lesion counts and acne severity grade at weeks 4, 8, 10, and 12. The ointment caused few side effects and was well tolerated by most patients.

Acne Vulgaris↗