Time-to-response was measured as the time (in weeks) from first dose of study drug to the time of first documentation of response. Response was defined as the participants achieving a PR or CR at any post-baseline response assessment. Per the 2014 NIH Consensus Development Project for Clinical Trials in cGVHD criteria; CR was defined as the resolution of all manifestations in each organ or site and PR was defined as the improvement in at least 1 organ or site without progression in any other organ or site

Best response was defined as the percentage of participants with CR or PR. Response was assessed per the 2014 NIH Consensus Development Project for Clinical Trials in cGVHD criteria; CR was defined as the resolution of all manifestations in each organ or site; PR was defined as the improvement in at least 1 organ or site without progression in any other organ or site. Organ response assessment was performed on 9 individual organs: skin, eyes, mouth, esophagus, upper gastrointestinal (GI), lower GI, liver, lungs, and joints and fascia and is reported in this outcome measure.

Lee cGVHD symptom scale, a patient-reported symptom scale used to measure symptom burden and has 7 subscales (Skin, Eyes and Mouth, Breathing, Eating and Digestion, Muscles and Joints, Energy, and Mental and Emotional) with ratings as follows: 0-Not at all, 1-Slightly, 2-Moderately, 3-Quite a bit, 4-Extremely, with lower values representing better outcome. Score for each subscale was normalized to a score ranged from 0 to 100, where higher score=worse symptoms. An overall Lee cGvHD score was calculated as average of these 7 subscales and it ranged from 0 to 100, where a higher score = worse symptoms. EOT visit was performed within 3 days after the participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication.

Failure-free survival was defined as the time (in months) from first dose of study drug to either the start of another new systemic treatment for cGVHD, relapse of the underlying disease or death. If no such events happened, FFS was censored by last response assessment or long term follow up assessment, whichever was the latest and available. Kaplan-Meier survival method was used for the analysis.

The TTNT was defined as the time (in months) from first treatment to the time of new systemic cGVHD treatment. TTNT was censored by last response assessment or long term follow up assessment, whichever was earlier. Kaplan-Meier survival method was used for the analysis.

Overall survival was defined as the time (in months) from first dose of study drug to the death due to any reason. If there was no death, OS was censored by last visit, last long-term follow-up, or study cut-off date, whichever occurred first. Kaplan-Meier survival method was used for the analysis.

Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. EOT visit was performed within 7 days after the participant's last dose of study drug.

Calcineurin inhibitors included systemic tacrolimus and cyclosporine. Number of participants who took CNI at Baseline and had reduction and discontinuation in CNI use as compared to Baseline during the study are reported in this outcome measure. EOT visit was performed within 7 days after the participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication.

The GSR assessment was performed by asking the participants to rate their disease severity of cGVHD symptoms on a 0 to 10-point numeric rating scale, where score 0 indicated 'not at all severe cGVHD symptoms' and score 10 indicated 'most severe cGVHD symptoms possible'. The response was defined using scores from 9 organs: skin, eyes, mouth, esophagus, upper gastrointestinal (GI) track, lower GI tract, liver, lungs, and joints and fascia plus GSR. End of treatment (EOT) visit was performed within 7 days after participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. Change from Baseline was calculated as GSR score at Baseline minus the lowest GSR score on scheduled visits with possible ranges from -10 to 10. The higher the number means the better improvement in cGVHD symptoms. Only those categories in which at least 1 participant had data were reported.

cGVHD symptom severity was self-reported by participants. Participants were asked to rate their disease symptom severity over the last week on the following questions: skin itching at its worst, moth dryness at its worst, mouth pain at its worst, mouth sensitivity at its worst, main compliant on eyes, symptom severity on eyes. Severity rating was done on a 0 to 10-point numeric rating scare, where score 0 indicated 'not at all severe cGVHD symptoms' and score 10 indicated 'most severe cGVHD symptoms possible'. EOT visit was performed within 7 days after participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. Change from Baseline was calculated as the symptom severity score at Baseline minus the lowest symptom severity score on scheduled visits minuswith possible ranges from -10 to 10. The higher the number means the better improvement in cGVHD symptoms.

The DOR was defined as the time (in weeks) from first documentation of response to the time of first documentation of deterioration from best response (e.g., CR to PR, or PR to LR). LOR included the response status of unchanged (LOR-U), mixed (LOR-M), or progression (LOR-P). Per the 2014 NIH Consensus Development Project for Clinical Trials in cGVHD criteria; CR was defined as the resolution of all manifestations in each organ or site; PR was defined as the improvement in at least 1 organ or site without progression in any other organ or site; LOR-M was defined as CR or PR in at least one organ accompanied by progression in another organ, LOR-U was defined as outcomes that did not meet the criteria for CR, PR, progression or mixed response, LOR-P was defined as progression in at least one organ or site without a response in any other organ or site. Kaplan-Meier was used for the analysis.

Analysis was performed on responder population which included participants who received at least 1 dose of study medication and achieved a PR or CR response at any post-baseline response assessment.

Time-to-response was measured as the time (in weeks) from first dose of study drug to the time of first documentation of response. Response was defined as the participants achieving a PR or CR at any post-baseline response assessment. Per the 2014 NIH Consensus Development Project for Clinical Trials in cGVHD criteria; CR was defined as the resolution of all manifestations in each organ or site and PR was defined as the improvement in at least 1 organ or site without progression in any other organ or site

Analysis was performed on responder population.

Best response was defined as the percentage of participants with CR or PR. Response was assessed per the 2014 NIH Consensus Development Project for Clinical Trials in cGVHD criteria; CR was defined as the resolution of all manifestations in each organ or site; PR was defined as the improvement in at least 1 organ or site without progression in any other organ or site. Organ response assessment was performed on 9 individual organs: skin, eyes, mouth, esophagus, upper gastrointestinal (GI), lower GI, liver, lungs, and joints and fascia and is reported in this outcome measure.

Participants received belumosudil 200 mg orally QD in each 28-day treatment cycle until disease progression, unacceptable toxicity, or death whichever occurred first. The number of participants analyzed is the number of patients with abnormalities in each organ.

Lee cGVHD symptom scale, a patient-reported symptom scale used to measure symptom burden and has 7 subscales (Skin, Eyes and Mouth, Breathing, Eating and Digestion, Muscles and Joints, Energy, and Mental and Emotional) with ratings as follows: 0-Not at all, 1-Slightly, 2-Moderately, 3-Quite a bit, 4-Extremely, with lower values representing better outcome. Score for each subscale was normalized to a score ranged from 0 to 100, where higher score=worse symptoms. An overall Lee cGvHD score was calculated as average of these 7 subscales and it ranged from 0 to 100, where a higher score = worse symptoms. EOT visit was performed within 3 days after the participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication.

Analysis was performed on mITT population.

Failure-free survival was defined as the time (in months) from first dose of study drug to either the start of another new systemic treatment for cGVHD, relapse of the underlying disease or death. If no such events happened, FFS was censored by last response assessment or long term follow up assessment, whichever was the latest and available. Kaplan-Meier survival method was used for the analysis.

Participants received belumosudil 200 mg orally QD in each 28-day treatment cycle until disease progression, unacceptable toxicity, or death whichever occurred first

The TTNT was defined as the time (in months) from first treatment to the time of new systemic cGVHD treatment. TTNT was censored by last response assessment or long term follow up assessment, whichever was earlier. Kaplan-Meier survival method was used for the analysis.

Participants received belumosudil 200 mg orally QD in each 28-day treatment cycle until disease progression, unacceptable toxicity, or death whichever occurred first.

Overall survival was defined as the time (in months) from first dose of study drug to the death due to any reason. If there was no death, OS was censored by last visit, last long-term follow-up, or study cut-off date, whichever occurred first. Kaplan-Meier survival method was used for the analysis.

Participants received belumosudil 200 mg orally QD in each 28-day treatment cycle until disease progression, unacceptable toxicity, or death whichever occurred first.

Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. EOT visit was performed within 7 days after the participant's last dose of study drug.

Participants received belumosudil 200 mg orally QD in each 28-day treatment cycle until disease progression, unacceptable toxicity, or death whichever occurred first.

Calcineurin inhibitors included systemic tacrolimus and cyclosporine. Number of participants who took CNI at Baseline and had reduction and discontinuation in CNI use as compared to Baseline during the study are reported in this outcome measure. EOT visit was performed within 7 days after the participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication.

Number of participants who took CNI at Baseline.

The GSR assessment was performed by asking the participants to rate their disease severity of cGVHD symptoms on a 0 to 10-point numeric rating scale, where score 0 indicated 'not at all severe cGVHD symptoms' and score 10 indicated 'most severe cGVHD symptoms possible'. The response was defined using scores from 9 organs: skin, eyes, mouth, esophagus, upper gastrointestinal (GI) track, lower GI tract, liver, lungs, and joints and fascia plus GSR. End of treatment (EOT) visit was performed within 7 days after participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. Change from Baseline was calculated as GSR score at Baseline minus the lowest GSR score on scheduled visits with possible ranges from -10 to 10. The higher the number means the better improvement in cGVHD symptoms. Only those categories in which at least 1 participant had data were reported.

Analysis was performed on mITT population.

cGVHD symptom severity was self-reported by participants. Participants were asked to rate their disease symptom severity over the last week on the following questions: skin itching at its worst, moth dryness at its worst, mouth pain at its worst, mouth sensitivity at its worst, main compliant on eyes, symptom severity on eyes. Severity rating was done on a 0 to 10-point numeric rating scare, where score 0 indicated 'not at all severe cGVHD symptoms' and score 10 indicated 'most severe cGVHD symptoms possible'. EOT visit was performed within 7 days after participant's last dose of study drug. Baseline value was defined as valid and last non-missing value obtained within 28 days prior to participant receiving first study medication. Change from Baseline was calculated as the symptom severity score at Baseline minus the lowest symptom severity score on scheduled visits minuswith possible ranges from -10 to 10. The higher the number means the better improvement in cGVHD symptoms.

Analysis was performed on mITT population.