To Evaluate Safety and Efficacy of Autologous CD19 Chimeric Antigen Receptor (CAR)-T Cells in Relapsed/Refractory B- Non-Hodgkin Lymphoma (B-NHL)

Inclusion Criteria: * Patients with histologically confirmed diagnosed with CD19 positive B cell NHL in accordance with WHO classification * Patients who are refractory to second-line treatment or patients who relapsed after first-line treatment with no available curative options such as autologous or allogeneic haematopoietic stem cell transplantation (HSCT) or relapse within one year of autologous HSCT * At least one measurable lesion according to revised IWG response criteria * Age between ≥13to ≤75 years * Adequate organ function as defined by a creatinine clearance \>40 ml/min, serum alanine transaminase (ALT) \< 5 times the normal value, serum bilirubin \< 3 times the normal value, left ventricular ejection fraction\> 45% * Absolute neutrophil count ≥ 1500/μl, haemoglobin level ≥ 7 g/dl, platelets ≥ 50000/μl. * Life expectancy \>12 weeks * Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2 * Female of childbearing age must have a negative pregnancy test and is on two effective contraception methods * Male patients must use two effective contraception methods Exclusion Criteria: * Active central nervous system (CNS) lymphoma (detected by Imaging study or cerebrospinal fluid (CSF) analysis) * Active cancer(other than NHL) or receiving cancer treatment * Evidence of severe lung, heart (New York Heart Association class III/IV, arrhythmia, heart block, uncontrolled hypertension), liver, or renal failure or severe neurologic disorder * Presence of active autoimmune disease requiring immunosuppressive therapy * Human Immunodeficiency Virus (HIV) positivity * Active Hepatitis B, and Hepatitis C infection * Uncontrolled infection * Pregnant/nursing female. * Receiving autologous or allogeneic stem cell transplant within 12 weeks of enrolment