Hair Depigmentation As an Indicator of Durable Response to CTLA-4 Therapy.

8571 Background: Treatment with CTLA-4 monoclonal antibodies for metastatic melanoma has been known to induce immunologically related adverse events. It is unclear if these events correlate with clinical responses. We report here, for the first time, the occurrence of hair depigmentation following therapy with CTLA-4 monoclonal antibodies that correlate with durable clinical responses. No non-responders developed any hair depigmentation. Methods: Patients (pts) enrolled onto 2 clinical trials at NYU using either ipilimumab (ipi) or tremelimumab (treme) for metastatic melanoma were evaluated. 43 pts were accrued (33-ipi and 10-treme). 11 pts achieved long-term, durable responses (3 complete responses and 8 partial responses) lasting over a median of 24 months. 5F:6M Age range: 37-78. All had normal baseline LDH levels. Results: Six pts developed sudden hair depigmentation starting with the eyebrows. Median time to depigmentation was 10 months. All 6 pts have continued to have either complete depigmentation...