mRSS, an accepted clinical measure of the skin thickness (fibrosis). Investigator physicians or qualified medical personnel assessed the thickening of skin in 17 skin sites including fingers, hands, forearms, arms, feet, legs and thighs, face, chest and abdomen. Each skin site was rated on a 0-3 scale; where 0 = normal skin, 1 = mild thickness, 2 = moderate thickness and 3 = severe thickness. Total mRSS ranged from 0 (no thickening) to 51 (severe thickening in all 17 areas), where higher score indicated more severity of skin thickening/worst outcome.