Entinostat & Chemotherapy for Locally Advanced or Metastatic Bladder Cancer

Inclusion Criteria: * Histopathologic confirmed unresectable advanced or metastatic bladder cancer, except for those with squamous differentiation, glandular differentiation or both; * Failure of first-line treatment; * There is at least one measurable lesion according to RECIST 1.1; * Archived tumor tissue samples or tumor biopsies must be provided; * ECOG score of 0-1 an an estimated survival of at least 6 months; * Adequate organ function; * Patients voluntarily participated in this study, signed the informed consent form, and had good compliance; * Women with fertility must consent to contraception during the study and for 6 months after the last dose of study drug. Exclusion Criteria: * Patients who received platinum-based chemotherapy after failure of first-line treatment; * Patients who received platinum-based chemotherapy withnin a 24 month before this trial; * Those who have received other anti-tumor treatment or participated in other clinical studies within 4 weeks before the start of the study, or have not recovered from the last toxicity (except grade 2 hair loss and grade 1 neurotoxicity); * Concomitant disease such as uncontrolled hypertension or diabetes, renal inadequacy, myocardial infarction, severe angina; * Female subjects who are pregnant, breastfeeding or planning to become pregnant during the study; * Patients with serious physical or mental illnesses.