Candonilimab and ATRA Acid for Prevention of Oral Cancer Recurrence in Patients With OPL

Inclusion Criteria:

1. Age: ≥18 years old.

2. Patients with a history of oral potentially malignant disorders and still presentingany of the following potential malignant manifestations upon oral examination: (1)oral mucosal leukoplakia, (2) oral mucosal morphological changes (thickening,proliferation, etc.), (3) gingival atrophy, dark red gums, (4) oral mucosal ulcers, (5) white tongue coating changes, (6) oral mucosal erythema, blood blisters, etc.

3. History of one occurrence of invasive oral cancer/carcinoma in situ, and haveundergone curative treatment.

4. Eastern Cooperative Oncology Group Performance Status (ECOG PS) score of 0-1.

5. Adequate function of important organs and bone marrow:

6. Hematology parameters: absolute neutrophil count (ANC) ≥ 1.5×10^9/L, plateletcount (PLT) ≥ 100×10^9/L, hemoglobin (HGB) ≥ 8g/dL.

7. Liver function: total bilirubin (TBIL) ≤ 1.5×upper limit of normal (ULN),alanine aminotransferase (ALT) and/or aspartate transferase (AST) ≤ 2.5×ULN.

8. Renal function: serum creatinine (Cr) ≤ 1.5×ULN.

9. Written informed consent and willingness to comply with the protocol procedures andvisits.

Exclusion Criteria:

1. Patients who require adjuvant treatment such as radiation therapy or chemotherapyaccording to the assessment based on the malignant tumor treatment guidelines afterthe most recent oral cancer surgery (at least meeting any of the following criteria:T3-4, N2-3, DOI > 5mm, positive surgical margins/ < 5mm).

2. Patients who have undergone a major surgery or have unhealed wounds, ulcers, orfractures within 4 weeks before the first dose of study treatment.

3. Patients who received the last dose of radiotherapy or last dose of anti-tumortreatment (chemotherapy, targeted therapy, or tumor embolization, etc.) within 4weeks before the first dose of study treatment.

4. History of exposure to any anti-PD-1, anti-PD-L1, anti-PD-L2, or anti-CTLA-4antibodies.

5. Concurrent participation in another interventional clinical study, unlessparticipating in an observational (non-interventional) clinical study or in thefollow-up phase of an interventional study.

6. Use of any investigational drug within 4 weeks before the first dose of studytreatment.

7. Use of immunosuppressive medication within 4 weeks before the first dose of studytreatment, excluding intranasal, inhaled, or topical corticosteroids or systemiccorticosteroids at physiologic doses (≤ 10 mg/day prednisone or equivalent dose ofother corticosteroids).

8. Vaccination with live attenuated vaccines within 4 weeks before the first dose ofstudy treatment or planned administration during the study.

9. Active, known, or suspected autoimmune diseases or medical history of such diseaseswithin the past 2 years (excluding vitiligo, psoriasis, alopecia, or Grave's diseasethat do not require systemic treatment within the past 2 years, well-controlledhypothyroidism requiring thyroid hormone replacement, and type 1 diabetes mellitusrequiring insulin replacement therapy).

10. Confirmed immunodeficiency disease.

11. History of allogeneic organ transplantation (excluding corneal transplantation) orallogeneic hematopoietic stem cell transplantation.

12. Known allergy to any monoclonal antibody component.

13. Uncontrolled severe diseases.

14. Coexistence of other malignancies, except for:

15. Cured malignancy (e.g., papillary thyroid carcinoma).

16. Non-melanoma skin cancer or malignancy resembling melanoma with no evidence ofdisease recurrence after adequate treatment.

17. Carcinoma in situ with no evidence of disease recurrence after adequatetreatment.

18. Pregnant or lactating patients. 5.4 Exclusion and Withdrawal Criteria.