The purpose of the study is to compare the efficacy and tolerability of budesonide 3 mg effervescent tablet (9 mg/day) compared to placebo for the treatment of patients with resistant oral cGvHD.

Inclusion Criteria:

• Karnofsky >= 70
• Oral chronic GvHD after allogeneic haematopoietic stem cell transplantation
• Oral cGvHD of erosive and/or ulcerative type
• NIH scale >= 3
• Resistant oral cGvHD with no oral response to conventional primary treatment

Exclusion Criteria:

• Uncertain diagnosis of resistant oral cGvHD
• Symptomatic oral cGvHD of hyperkeratotic type solely
• Current active oral bacterial, viral, or fungal infection
• Unwilling to forego concurrent treatment for mucosal lesions and/or related oral pain
• Requiring addition of new systemic therapy including steroids, or radiation therapy
• Local intestinal infection
• Abnormal hepatic function or liver cirrhosis
• If careful medical monitoring is not ensured: tuberculosis, cardiovascular disease, diabetes mellitus, osteoporosis, active peptic ulcer disease, glaucoma, cataract, infection
• Second line treatment of oral cGvHD with topical steroids