When treating patients with vitiligo, what is your minimum trial duration before declaring topical ruxolitinib a failure?

Trial of 3 months, and always advise ambient sunlight (between 7- 9 a.m., 10-15 min) if possible. There is evidence of enhanced improvement when combining NBUVB + Rux. Before initiating treatment, I also let the patient know facial vitiligo responds best to topical ruxolitinib.