New York, June 25 (IANS): A drug used for treating rheumatoid arthritis has restored skin colour in a female patient suffering from vitiligo -- a common, skin condition where portion of skin loses its pigmentation or colour, says a new study.

"It is a first, and it could revolutionise treatment of an awful disease," said principal investigator of the research Brett King, assistant professor of dermatology Yale School of Medicine in the US.

Treatment with the drug tofacitinib nearly removed the white spots on her face and hands without causing any side effects, the findings showed.

The study offers hope to millions of people suffering from from the disfiguring condition best known as the disease that plagued late pop star Michael Jackson.

"This may be a huge step forward in the treatment of patients with this condition," King said.

Current vitiligo treatments, such as steroid creams and light therapy, are not reliably effective in reversing the disease. For the study, the researchers administered tofacitinib to a 53-year-old patient with prominent white spots covering her face, hands, and body.

For more than a year prior to taking tofacitinib, the numbers of these white spots had been increasing.

Within two months of treatment, the patient experienced partial repigmentation on her face, arms, and hands -- the areas that concerned her most. After five months, the white spots on her face and hands were nearly gone, with only a few spots remaining on other parts of her body.

Notably, tofacitinib caused no adverse side effects during the course of treatment, the study noted.

"The results could represent a breakthrough in vitiligo treatment," the researchers said.

"While it is one case, we anticipated the successful treatment of this patient based on our current understanding of the disease and how the drug works," King added.

King said further research would be necessary to confirm the drug's safety and efficacy.

The finding was published in JAMA Dermatology.