This is a multicenter prospective single arm phase II study. The purpose of this study is to evaluate the safety and efficiency of azacytidine combined with chidamide in the treatment of relapsed/refractory angioimmunoblastic T-cell lymphoma.

Azacytidine was given subcutaneously at a dose of 75 mg/m2 on days 1-7. Chidamide was an oral tablet which was administered 20mg twice weekly. This regimen was repeated every 28 days. Treatment was given until disease progression, unacceptable toxicity, or patient/investigator discretion.

Inclusion Criteria:

• Pathologically confirmed angioimmunoblastic T-cell lymphoma according World Health Organization (WHO) classification;
• Age≥18years;
• ECOG≤2;
• Patients received at least one systemic treatment previously and achieved no remission or relapsed after first-line treatment;
• Adequate bone marrow hematopoietic function: ANC>1.5 × 109/L，HGB>90g/L，PLT>80 × 109/L;
• Adequate organ function: ALT≤3 times ULN, TBil≤1.5 times ULN, SCr≥50ml/min/m2, cardiac function grade 0-2 (NYHA);

Exclusion Criteria:

• Active or uncontrolled infections requiring systemic treatment within 14 days before enrollment;
• Any instability of systemic disease, including but not limited to severe cardiac, liver, kidney, or metabolic disease need therapy;
• Pregnant or lactating women;