Immunotherapy with Mycobacterium vaccae in patients with newly diagnosed pulmonary tuberculosis: a randomised controlled trial. Durban Immunotherapy Trial Group.
BACKGROUND
Mycobacterium vaccae, an environmental saprophyte, has immunogenic properties that enhance the host immune response. Immunotherapy with M. vaccae has been suggested to shorten short-course antituberculosis chemotherapy. We tested the hypothesis that the addition of M. vaccae to standard short-course antituberculosis chemotherapy would decrease the time to achieve a negative sputum culture.


METHODS
Patients with newly diagnosed tuberculosis were randomly assigned an injection of saline (placebo) or M. vaccae on day 8. All patients received antituberculosis chemotherapy with rifampicin, isoniazid, pyrazinamide, and ethambutol. Sputum samples were checked by microscopy and culture every week for the first 8 weeks and monthly until the end of chemotherapy at 6 months. The primary outcome was the time to a negative sputum culture in the first 8 weeks. Intention-to-treat analysis was used and time to sputum clearance was assessed by log-rank test and Cox's proportional-hazards regression.


RESULTS
172 patients received M. vaccae and 175 patients received placebo. At 8 weeks, 70 patients in the M. vaccae group and 65 patients in the placebo group had a negative culture; there was no difference between groups in the time to a negative culture (p=0.83). There was no interaction between HIV status and treatment.


CONCLUSIONS
M. vaccae immunotherapy has no benefit when added to standard antituberculosis chemotherapy.
D017088:AIDS-Related Opportunistic Infections / Q000188:drug therapy / Q000401:mortality / Q000628:therapy; D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D005260:Female; D006679:HIV Seropositivity / Q000150:complications; D006801:Humans; D007167:Immunotherapy; D008297:Male; D009161:Mycobacterium / Q000276:immunology*; D016016:Proportional Hazards Models; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy / Q000401:mortality / Q000628:therapy*
D000995:Antitubercular Agents