Backline Treatment of Advanced Hepatocellular Carcinoma With Palbociclib

Inclusion Criteria: 1. Patients aged ≥18 years and ≤75 years; 2. ECOG score 0\~2; 3. Patients with histologically or cytologically confirmed unresectable advanced hepatocellular carcinoma; 4. Patients who have failed or are intolerant of at least second-line treatment; 5. Expected survival ≥ 3 months; 6. An evaluable lesion within 21 days prior to enrollment according to RECIST 1.1 criteria; 7. Barcelona Clinical Liver Cancer Staging (BCLC staging) stage B or C and not suitable for surgical or local treatment, or progression after surgery or local treatment; 8. Child-Pugh Liver Function Class: Grade A or B (≤7 points); 9. HBV DNA quantification must be \<500IU/ml or 2500 copies/ml and receive at least 2 weeks of anti-HBV treatment before study entry; HCVRNA quantification-positive patients must have completed antiviral treatment at least 1 month before study entry; 10. CNS metastases without clinical symptoms or with clinical symptoms controlled and stabilized for ≥4 weeks after treatment： (1) Routine blood tests should meet the following criteria: ANC ≥1.0×109/L; PLT ≥50×109/L; Hb ≥80 g/L; (2) Biochemical tests must meet the following criteria: TBIL ≤ 3 times the upper limit of normal (ULN); ALT and AST ≤ 5 times the upper limit of normal (ULN); serum creatinine ≤ 1.5 × ULN or creatinine clearance rate \> 50 ml/min (Cockcroft-Gault formula); (3) Coagulation examination criteria to be met: prothrombin time (PT) ≤ 1.5 x ULN, activated partial thromboplastin kinase time (aPTT) ≤ 1.5 x ULN; (4) Cardiac ultrasound and echocardiography: left ventricular ejection fraction (LVEF ≥ 55%), ECG QTc \< 450ms (men), QTc \< 470ms (women); 13. Patients who agree to abstain from sex or use an effective method of contraception for the duration of treatment and for at least 7 months after the last dose of study treatment; 14. Signed informed consent. Exclusion Criteria: 1. Prior treatment with any CDK4/6 inhibitor drug; 2. Patient has received antitumor therapy in another clinical trial within 4 weeks prior to enrollment; 3. Patient has undergone a major surgical operation within 4 weeks prior to enrollment or the patient has not fully recovered from such surgical operation; 4. Severe cardiac disease or discomfort; 5. Hepatitis B combined with Hepatitis C or Hepatitis D infection; 6. Patient is allergic to the components of the drug perphenazine or its excipients; 7. Other malignant tumors within 5 years (except cured basal cell carcinoma of the skin, carcinoma in situ of the prostate and carcinoma in situ of the cervix); 8. Those with multiple factors affecting the oral administration of drugs (e.g. inability to swallow, post gastrointestinal resection, chronic diarrhea and intestinal obstruction, etc.); 9. Pregnant or breastfeeding female patients, female patients of childbearing potential with a positive baseline pregnancy test, or patients of childbearing potential who are unwilling to use effective contraception throughout the trial period and for 7 months after the final study dose; 10. Severe concomitant disease or other co-morbidities that would interfere with planned therapy, or any other condition that, in the opinion of the investigator, makes the patient unsuitable for participation in this study.