ORR according to NIH cGVHD 2015 response criteria using blinded and investigator assessments at week 28 by severity. LOCF data are reported for the ITT population (n = 53) for patients with moderate cGVHD using blinded (A) and investigator (B) assessments and severe cGVHD using blinded (C) and investigator (D) assessments. Percentages are based on the number of patients treated in the relevant treatment group with no missing responses. Error bars represent 95% CI calculated using the exact method of binomial distribution. Fisher’s exact test was used to compare the ORRs between patients treated with SoC+ECP compared with SoC; blinded assessments in moderate cGVHD patients, P = .234; and severe cGVHD patients, P > .999; investigator assessments in moderate cGVHD patients, P > .999; and severe cGVHD patients, P = .198.