Application of PD-1 Inhibitors Combined With Tenofovir, Chidamide and Lenalidomide in the Treatment of EBV-associated Diseases.

• PD-1 Inhibitor Combined with Tenofovir, Chidamide, and Lenalidomide for the Treatment of EBV Infectious Diseases. (Drug): This study involves a four-drug combination regimen consisting of a PD-1 inhibitor, tenofovir, chidamide, and lenalidomide for the treatment of EBV Infectious diseases, aiming to inhibit viral replication and restore immune function through multiple mechanisms. The intervention includes not only pharmacological treatment but also pre-treatment assessments (such as EBV-DNA load, immune status, cardiac and renal function), efficacy monitoring during treatment (e.g., ORR, changes in EBV-DNA), and post-treatment follow-up for safety and survival outcomes (including OS, PFS, and adverse events), in order to comprehensively evaluate the clinical value and feasibility of this combination therapy.

Primary outcomes

• Overall Response Rate (ORR), including Complete Response (CR) and Partial Response (PR), based on EBV-DNA levels. [After 3 months of treatment according to the study protocol, a comprehensive efficacy assessment will be conducted. Patients achieving CR or PR will continue treatment, while those with SD or PD will be withdrawn from the study.]

Secondary outcomes

• 24-month overall survival rate of EBV-infected diseases. [From first dose until death from any cause (assessed at 24 months）]: Proportion of patients alive at 24 months after initiation of tirelizumab combination therapy.
• 24-month progression-free survival rate of EBV-infected diseases. [From first dose until first documented progression or death (assessed at 24 months)]: The proportion of patients with no disease progression at 24 months based on EBV DNA results.

Sex: All, ages: 0 Years to 75 Years

Inclusion Criteria:

1. Diagnosed with EBV infectious diseases, including infectious mononucleosis, chronic active EBV infection, or other EBV infectious diseases;
2. EBV DNA ≥ 10⁴ copies/mL in whole blood or plasma;
3. Age ≤ 75 years with ECOG performance status ≤ 2;
4. Estimated life expectancy over 3 months;
5. Patients must be able to undergo follow-up. They should understand the nature of their disease and voluntarily agree to participate in this study for treatment and follow-up.

Exclusion Criteria:

1. Patients with impaired liver or kidney function, specifically defined as serum direct bilirubin, indirect bilirubin, and/or ALT, AST, or serum creatinine >2 times the upper limit of normal (ULN), unless such abnormalities are attributed to lymphoma;
2. Patients with bone marrow failure, defined as absolute neutrophil count (ANC) <1.5×10⁹/L or platelets <75×10⁹/L;
3. Patients who have experienced grade III or higher neurotoxicity within the past 2 weeks;
4. Patients with chronic heart failure classified as NYHA class III or IV, or left ventricular ejection fraction (LVEF) <50%, or those with a history of the following cardiac events within the past 6 months: acute coronary syndrome, acute heart failure (NYHA class III or IV), or significant ventricular arrhythmias (sustained ventricular tachycardia, ventricular fibrillation, or resuscitated sudden cardiac arrest);
5. Patients with AIDS, syphilis, or active hepatitis B (HBV DNA >1×10⁴ copies/mL) or hepatitis C infection;
6. Patients with coexisting hematologic disorders (e.g., hemophilia, myelofibrosis) deemed unsuitable for inclusion by the investigator;
7. Patients with severe concurrent infections;
8. Patients who have undergone grade II or higher surgery within 3 weeks prior to treatment;
9. Patients with substance abuse, medical, psychological, or social conditions that may interfere with study participation or the evaluation of study outcomes;
10. Patients deemed unsuitable for enrollment by the investigator;
11. Patients with known hypersensitivity to components of the investigational drug.