This study suggested that hydrogen has a potential as an effective and safe therapeutic agent on cGVHD.

The investigators will evaluate clinical response rate, time to treatment Failure (TTF), overall survival (OS), and toxicity in cGVHD patients.

Inclusion Criteria:

• Written informed consent
• Male
• not pregnant female
• patients <65 years old
• Diagnosis of cGVHD steroid refractory (no response after Prednisone ≥1mg/kg ) or steroid-dependent cGVHD (had an initial response followed by a cGVHD flare upon steroid taper)
• Patient intolerant to steroid therapy

Exclusion Criteria:

• Patients with stable disease, not well controlled by the current treatment
• Pregnancy
• HIV positive
• Severe liver or renal impairment: serum creatinine >2.5 mg/dl; serum bilirubin>2.5 mg/dl (without evidence of hepatic cGVHD)
• Uncontrolled malignancies including the persistence of the underlying malignancy before the Allogeneic Transplantation and the relapse of hematopoietic malignancy
• Any other investigational agents administered within last four weeks
• Cardiac insufficiency (>grade II, New York Heart Association classification)
• Inability to comply with medical therapy or follow-up