• Objective:This study aims to assess the efficacy and safety of Chidamide as a monotherapy maintenance treatment for patients with newly diagnosed peripheral T-cell lymphoma (PTCL) who have achieved remission or stable disease after initial brentuximab vedotin (BV) plus cyclophosphamide, doxorubicin and prednisone (CHP)treatment, excluding ALK+ anaplastic large-cell lymphoma (ALCL).
• Design: The study is a prospective, single-center, open-label clinical trial.
• Treatment:Eligible patients will receive Chidamide tablets at a dosage of 20 mg (4 tablets) twice weekly. Treatment cycles are 4 weeks long and will continue until disease progression, unacceptable toxicity, patient withdrawal, investigator decision to discontinue, loss to follow-up, death, or study termination.
• Endpoints:The primary endpoint is the 2-year progression-free survival (PFS). Secondary endpoints include the overall response rate (ORR), overall survival (OS), and safety indicators.
• Rationale:The study seeks to provide a basis for the dosing regimen of Chidamide and contribute to the development of effective maintenance treatment strategies for PTCL patients.

Inclusion Criteria:

1. According to the WHO 2016 diagnostic criteria, the histological diagnosis is confirmed as CD30+ peripheral T-cell lymphoma (PTCL), including peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), angioimmunoblastic T-cell lymphoma (AITL), anaplastic large cell lymphoma (ALK- ALCL), enteropathy-associated T-cell lymphoma (EATL), and other pathological subtypes (excluding extranodal NK/T-cell lymphoma, nasal type [NKTCL]). Patients with newly diagnosed PTCL (excluding ALK+ ALCL), who have completed 6 cycles of first-line treatment regimens (including various first-line induction chemotherapy regimens, targeted drugs, other treatment plans, and various combined therapies, etc.; with or without the inclusion of Chidamide) and have achieved complete remission (CR), and are not suitable for or do not consider undergoing autologous hematopoietic stem cell transplantation. Within 12 weeks from the first day of the last cycle of their first-line treatment regimen, they start to receive the medication plan of this study.
2. Age ≥18 years, male or female is not limited;
3. ECOG performance status score 0-3;
4. Neutrophils ≥1.5×10^9/L, platelets ≥80×10^9/L, hemoglobin ≥90g/L;
5. Expected survival time ≥3 months;
6. Voluntarily sign a written informed consent form.

Exclusion Criteria:

1. Pregnant or lactating women and women of childbearing age who are unwilling to adopt contraceptive measures;
2. Patients with a history of clinically significant prolongation of the QTc interval (males > 450ms, females > 470ms), ventricular tachycardia (VT), atrial fibrillation (AF), cardiac conduction block, myocardial infarction within the past year, congestive heart failure (CHF), and patients with symptomatic coronary artery disease requiring medication;
3. Patients who have undergone organ transplantation;
4. Patients who have received symptomatic treatment for previous bone marrow toxicity within 7 days prior to enrollment;
5. Patients with active bleeding;
6. Patients with a history of thrombosis, embolism, cerebral hemorrhage, cerebral infarction, or other related diseases;
7. Patients with active infection or those who have had persistent fever within 14 days prior to enrollment;
8. Patients who have undergone major organ surgery within the past 6 weeks;
9. Patients with abnormal liver function (total bilirubin > 1.5 times the normal value, ALT/AST > 2.5 times the normal value, or in liver-infiltrated patients ALT/AST > 5 times the normal value), and abnormal kidney function (serum creatinine > 1.5 times the normal value);
10. Patients with mental disorders/those who are unable to give informed consent;
11. Patients with drug abuse or chronic alcoholism that affects the evaluation of the trial results;
12. Patients with lymphoma involving the central nervous system;
13. Patients deemed by the investigator to be unsuitable for participation in this study.