Louise Gagnon is a medical writer and editor based in Oakville, Ontario, Canada.
Topical immunomodulators are effective in managing pediatric vitiligo over six months, with no serious adverse events observed, one study has found. More extended treatment will provide a better sense of efficacy with these therapies in the longer term.
Montreal - Both clobetasol propionate and tacrolimus are effective in treating vitiligo in the pediatric setting, according to an investigator-initiated study presented here at the annual meeting of the Canadian Dermatology Association.
Vitiligo is an acquired autoimmune condition characterized by a progressive disappearance of melanocytes resulting in depigmentation of the skin and the hair, says Nhung Ho, M.D., a pediatric dermatologist at the Hospital for Sick Children in Toronto, Ontario, Canada.
The incidence of the condition is 1 percent to 4 percent. About half of the patients have onset of disease before the age of 20, and 25 percent have onset of the disease before the age of 10.
The pathogenesis of the condition remains unknown, Dr. Ho says, but the theory that the condition is autoimmune in nature is widely accepted.
Some retrospective research published last year demonstrated efficacy with corticosteroids to treat the condition, but local side effects occurred with their continual use, according to Dr. Ho, assistant professor at the University of Toronto, Toronto. The data from that study suggested more intermittent treatment with corticosteroids would be more likely to forestall the onset of local side effects.
Dr. Ho tells Dermatology Times that both clobetasol proportionate 0.05 percent and tacrolimus 0.1 percent have been shown to be effective and safe in treating vitiligo, but specific research in the pediatric population has not been conducted to support which is the safer and more effective choice.
Current therapy used at the Hospital for Sick Children for children with vitiligo involves the use of clobetasol proportionate 0.05 percent being applied for six to eight weeks in an on-and-off cycle, with tacrolimus 0.1 percent being used on the face, Dr. Ho says.
"The objective of our clinical study was to compare the efficacy of the treatment with placebo," she says.
The prospective, randomized, double-blinded, placebo-controlled study saw 100 children randomized to one of three groups for six months. Patients in the study, ages 2 to 16, with less than 20 percent body surface area of vitiligo were recruited from two different sites. There was a washout period of at least four weeks.
Patients were excluded from the study if they showed signs of infection stemming from the application of therapy.
Patients were randomized to either clobetasol propionate 0.05 percent ointment for two months on and two months off (33); tacrolimus 0.1 percent ointment (34); or six months of placebo (33). Patients were further stratified to "face" and "nonface" groups, Dr. Ho says.
Investigators defined successful repigmentation as greater than 50 percent improvement. They measured improvement through photographs captured at the study entry, two months, four months and six months.
Researchers found equal rates of efficacy between the clobetasol propionate arm (58 percent) and the tacrolimus arm (58 percent) in the facial group, with the difference not being statistically significant.
When comparing the nonfacial group, 39 percent of the clobetasol propionate arm responded successfully versus 23 percent of patients receiving tacrolimus therapy, p=0.30.
"The response with clobetasol appeared to be equivalent between facial and nonfacial lesions," Dr. Ho says.
"We saw with tacrolimus, however, that the facial lesions seem to be responding much better (than nonfacial lesions)," she says.
Moreover, investigators found statistically significant differences in response between patients receiving clobetasol proprionate and patients receiving tacrolimus versus placebo, p<0.0001 and p=0.0004, respectively.
Investigators observed the most common pattern of repigmentation was diffuse in the clobetasol propionate arm, while it was diffuse and mixed in the tacrolimus arm.
About a quarter of patients on placebo did respond to therapy (24 percent). Specifically, five out of 29 patients had less than 50 percent repigmentation, and two patients had more than 50 percent repigmentation. This represents an incidence of 2.4 percent of spontaneous repigmentation, which is higher than 1.3 percent reported in the literature, according to Dr. Ho.
The therapies were well-tolerated with some transient erythema observed, but no atrophy was noted, Dr. Ho says.
This study shows that topical immunomodulators, in particular tacrolimus, are safe therapy in localized vitiligo in children, with the efficacy comparable to topical potency corticosteroids. Perhaps double-blinded, placebo-controlled studies of a longer duration will lead to a more conclusive efficacy rate, Dr. Ho says.
Clinicians continue to search for new practical therapies with greater efficacy, while preserving maximum safety.
Disclosure: Dr. Ho reports no relevant financial interests.