⁃ All patients must meet all the following criteria:

• Must be informed of the investigational nature of this study and must provide written informed consent

• Age ≥18 years, male or female

• Non-muscle invasive transitional cell carcinoma of the bladder is histologically confirmed by Independent Pathology Review Committee (IPRC). Diagnosis and classification of intermediate-risk NMIBC is according to 2014 CUA Guideline of Diagnosis and Treatment of Urological Diseases in China:

⁃ Low-risk: Primary, solitary, TaGl (PUNLMP, low-grade urothelial carcinoma), \<3cm, no CIS. (Note: the above conditions must be met at the same time as a low-risk NMIBC) Intermediate-risk: All tumours not defined in the two adjacent categories (between the category of low and high risk) High-risk: Any of the following: ① T1 tumour; ②G3(high-grade urothelial carcinoma) tumour;③carcinoma in situ (CIS); ④ Multiple, recurrent and large (\> 3 cm) TaG1G2(low-grade urothelial carcinoma) tumours (all features must be present)

⁃ • No visible tumor after transurethral resection of bladder tumor (TURBT) on tumor lesion. Some requirements about Re-TURBT are as follows: It is recommended to conduct the secondary TURBT under following situations: incomplete first TURBT; no muscle tissue found in the first TURBT specimen, except Ta G1 (low grade) tumor and CIS only.

⁃ The secondary TURBT is recommended 2-6 weeks, but better at 4 weeks, after the first TURBT.

⁃ For subjects undergoing secondary TURBT, they will be enrolled after the second TURBT

• Subjects who never received intravesical instillation (including BCG or intravesical chemotherapy) prior to enrollment, except single, immediate, post-operative intravesical chemotherapy.

• Willing to provide pathological tissue specimen for assessment

• ECOG PS ≤ 1

• Patients, who have not received blood transfusion or colony-stimulating factor treatment within 14 days before the examination, must have normal organ and marrow function within 42 days of study entry (according to normal range in clinical site).

⁃ Absolute neutrophil count \>1.5×109/L Platelets \> 100 ×109/L Hemoglobin \> 9.0 g/dL Alkaline phosphatase \< 2.5 ULN GFR (Cockcroft-Gault formula calculated) ≥ 50 mL/min Total bilirubin, alanine aminotransferase or aspartate aminotransferase\< 1.5 ULN INR \<1.5, except for subjects receiving anticoagulation therapy

• Female should be either surgically sterilized or menopause or agree to use effective contraceptive measures during treatment. Women of reproductive age must have a negative result of pregnancy test during the screening period (pregnancy test will be not required if one of the following situations exists: the subject has undergone sterilization such as hysterectomy and/or bilateral oophorectomy, has no menstruation for 12 months and been diagnosed as menopause based on factors such as age). However, pregnancy tests are required for patients with bilateral fallopian tube ligation.

• Male subjects should be either surgically sterilized or agreed to use effective contraceptive measures. From signing the informed consent, subjects must take continuous measures until 3 months after the end of the treatment of trial. The definition of effective contraceptive measures will be based on the principal investigator(PI) or appointed delegate.

• Expected life expectancy is more than 48 months