The Efficacy of CAPCT in Patients With PTCL

• Chidamide (Drug): Chidamide tablets,：Oral administration at a dose of 20 mg (4 tablets) per intake, twice weekly, with an interval of no less than 3 days between the two doses .
• Azacitidine (AZA) (Drug): Subcutaneous injection at a dose of 100 mg/day on Days 1-7
• Prednisone (Drug): Oral administration at a dose of 20 mg/day, taken after breakfast.
• Cyclophosphamide (Drug): Oral administration at a dose of 50 mg/day, taken after lunch.
• Thalidomide (100mg) (Drug): Oral administration at a dose of 100 mg/day, taken before bedtime.

Primary outcomes

• Objective Response Rate（ORR） [Up to 2 years]: The proportion of patients who achieve a CR 、CRu and PR

Secondary outcomes

• Duration of Response（DoR） [Up to 2 years]: The time from the first documented objective response (CR or PR) to the first documented disease progression or death from any cause.
• Progression-Free Survival（PFS） [From treatment to the end of treatment at 12months]: The time from the start of treatment to the first documented disease progression or death from any cause, whichever occurs first.
• Overall Survival（OS） [From treatment to the end of treatment at 24 months]: The time from the start of treatment to death from any cause.
• Adverse Event [From enrollment to the end of treatment at 24 months]: AEs

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* 1\. Patients with histopathologically confirmed peripheral T-cell lymphoma (PTCL), with exclusion of NK/T-cell lymphoma.
* 2\. Patients who are treatment-naïve or have relapsed/refractory disease.
* 3\. Patients who are intolerant to standard chemotherapy regimens for various reasons, including those aged ≥75 years, or those aged <75 years but deemed by the investigator to be unsuitable for or unable to tolerate chemotherapy.
* 4\. Patients aged ≥18 years, male or female.
* 5\. Eastern Cooperative Oncology Group (ECOG) performance status score of 0-3.
* 6\. Absolute neutrophil count ≥1.5×10⁹/L, platelet count ≥50×10⁹/L, and hemoglobin ≥70 g/L.
* 7\. Estimated life expectancy ≥3 months.
* 8\. Voluntary signing of written informed consent.

Exclusion Criteria:

* 1\. Pregnant or lactating women, or fertile patients of childbearing potential who are unwilling to adopt contraceptive measures.
* 2\. Patients with chronic heart failure of New York Heart Association (NYHA) functional class III or IV; or those with a history of any of the following cardiac conditions within 6 months: acute coronary syndrome; acute heart failure (NYHA functional class III or IV); or significant ventricular arrhythmias (sustained ventricular tachycardia, ventricular fibrillation, or sudden cardiac death after resuscitation).
* 3\. Hepatic dysfunction (total bilirubin >1.5× the upper limit of normal \[ULN\]; alanine aminotransferase \[ALT\] and aspartate aminotransferase \[AST\] >2.0× ULN, or >5× ULN in patients with hepatic involvement); or renal dysfunction (serum creatinine >1.5× ULN).
* 4\. Confirmed central nervous system (CNS) involvement by lymphoma.
* 5\. Receipt of prior myelosuppressive symptomatic treatment within 7 days before enrollment.
* 6\. Active hemorrhage/bleeding.
* 7\. Patients with acquired immunodeficiency syndrome (AIDS), syphilis, or active hepatitis B (HBV DNA >1×10⁵ copies/mL) or hepatitis C.
* 8\. Receipt of grade II or higher surgery within 3 weeks prior to treatment.
* 9\. Psychiatric disorders or inability to provide informed consent.
* 10\. Patients deemed by the investigator to be unsuitable for participation in this trial.
* 11\. Known allergy to any component of the investigational drug.