Safety and Efficacy of Blocking IL-4 With Pascolizumab in Patients Receiving Standard Therapy for Pulmonary Tuberculosis

Inclusion Criteria: 1. Aged 21 -75 years of age 2. Male or female: females eligible only if not of childbearing potential or agree to remain abstinent or use an appropriate contraceptive method during the study. 3. Confirmed pulmonary TB by smear microscopy and Gene Xpert™ 4. Absence of rifampicin resistance on molecular probe (Gene Xpert™) 5. Estimated to be able to produce at least 5ml of sputum per 24 hour period. 6. No previous history of anti-TB therapy for active disease (treatment for latent disease acceptable). 7. Willing to comply with the study visits and procedures 8. Willing and able to provide written informed consent Exclusion Criteria: 1. More than 28 days of standard anti-TB chemotherapy at the time of randomization. 2. Disseminated TB (lymphadenopathy is acceptable) 3. Underlying serious chronic diseases such as those of the liver, kidney disease, blood disorders and Type I diabetes (controlled Type II diabetes is acceptable) or any significant organ dysfunction. 4. History of myocardial infarction, congestive heart failure or arrhythmia within 6 months of screening 5. History or evidence of chronic alcohol consumption or drug abuse 6. Current autoimmune disease or history of autoimmune disease. 7. Known or suspected hypersensitivity to any component of the trial medication (sodium phosphate, sodium chloride, glycine, sucrose, polysorbate 80) 8. Chronic use of an immunosuppressant 9. Treatment with any monoclonal antibody within 6 months of randomization 10. Vaccination within the 6 weeks prior to randomization (patients who have received influenza vaccination can enroll at 2 weeks following vaccination). 11. Seropositive for human immunodeficiency virus-1 or 2; hepatitis B surface antigen (HBsAg) or hepatitis C virus (HCV) antibodies at screening 12. Creatinine \> 1.4 times upper limit of normal or ALT greater than 2.5 times upper limit of normal on screening blood tests 13. QTc \>450 msec on ECG performed at screening 14. Women who are currently pregnant or breastfeeding 15. Any other significant condition that would, in the opinion of the investigator, compromise the patient's safety or outcome in the trial. 16. Participation in other clinical intervention trial or research protocol (Participation in other studies that do not involve an intervention may be allowed, but this must be discussed and approved by Chief Investigator )