Vitiligo May Be Associated With Pembrolizumab Treatment Outcome

Vitiligo, a clinically visible immune-related adverse event of the skin that reacts against melanocytes, may be associated with tumor response in patients with metastatic melanoma treated with pembrolizumab, a new study published online ahead of print in JAMA Dermatology has shown.¹

Although it has been hypothesized that vitiligo is associated with tumor response in patients with melanoma who undergo immunotherapy, the evidence has been controversial.

Therefore, researchers at Gustave Roussy Institute in France sought to prospectively assess the appearance of the autoimmune skin disorder in patients receiving pembrolizumab.

The researchers identified 67 patients with metastatic melanoma who had received pembrolizumab as part of a phase 1 study at their institution and screened them for the emergence of vitiligo. Of those, 17 developed vitiligo during treatment and 50 did not.

Results showed that objective response rate was 71% in the vitiligo group and 28% in the group that did not develop vitiligo (P = .002).

Of those with vitiligo, 3 achieved a complete response, 9 achieved a partial response, 3 had stable disease, and 2 had experienced disease progression at the time of final follow-up. With a median follow-up of 441 days, all patients who had developed vitiligo were alive at the time of analysis.

“Better understanding of immunity against melanocytes in melanoma, which clinically manifest as vitiligo, might contribute to the identification of other targets for immunotherapy against melanoma,” the authors concluded.

Reference

1. Hua C, Boussemart L, Mateus C, et al. Association of vitiligo with tumor response in patients with metastatic melanoma treated with pembrolizumab [published online ahead of print October 21, 2015]. JAMA Dermatol. doi: 10.1001/jamadermatol.2015.2707.