The Preliminary Research On Basic And Clinical Research Of Treating MDR-TB With Clofazimine

Background:Clofazimine, which was found in 1944 during the developing of new anti-tuberculosis drugs, no more research and application on tuberculosis because it has no activity against Mycobacterium tuberculosis in the guinea pigs and monkeys models. Fortunately, it was effect on the research of anti-leprosy bacilli, used in treating leprosy and bird-Mycobacterium disease for many years. There was few report on the research of anti-tuberculosis activity with Clofazimine. Because it is very difficult to treat the MDR-TB and XDR-TB in the world especially in China, we carried out the basic and clinical studies on the tuberculosis of Clofazimine, the object is to estimate the activity of anti-tuberculosis and supply the base to clinical application, which will be an anti-tuberculosis drug especially to the drug-resistant TB.Object:We observed the in vitro activity against Mycobacterium tuberculosis standard strain and Mycobacterium tuberculosis clinical resistant strains, and the effect in vivo in mice TB models treated with Clofazimine. The tissue distribution of Clofazimine and the effect of Isoniazid,Pyrazinamide to the tissue distribution of it. We adopted the method of self-control to estimate the efficacy and safety of Clofazimine combined with other anti-tuberculosis drugs in treating the MDR-TB, and help the clinical application of Clofazimine to treat the drug resistant TB.Method:1. Apply the microplate Alamar Blue method to determine the MIC of Clofazimine to standard strains of mycobacterium tuberculosis and 30 clinical isolates of MDR mycobacterium tuberculosis. Design tuberculosis mice model infected with H37RV 1×105CFU through vein, administer Clofazimine 20mg/kg(CLF-1) 5 times a week; 10 mg/kg(CLF-2) 5 times a\week and 20 mg/kg (CLF-3) 2 times a week; after 30 days we achieved the viable count to evaluate the anti-TB activity of Clofazimine in mice, and estimate the effect on the tuberculosis model mice which infected the clinical isolates of drug resistant mycobacterium tuberculosis were treated with Clofazimine and combined chemotherapy for 60 days.2. Study the tissue distribution of Clofazimine and the effect by isoniazid,pyrazinamide which administration one time in BALB/C mice, after administration 1h,5h,24h, blood from infraorbital or eyeball extraction. Determined the concentration of liver, kidney, spleen, lungs, fat, etc using by HPLC.3. Preliminary study on MDR-TB treated with Clofazimine. We choose the multi-drug resistant TB patients, signed informed consent voluntarily, aged from 18 to 65 years, and adopt the 24-month own control clinical trials. Based on the sensitivity test results, We select 5-7 kinds of drugs to strengthen period for 6 months and consolidation period for 24 months including Clofazimine (Cfm), Protionamide (Pto), Sodium Aminosalicylate (PAS), Levofloxacin (Lfx), Clarithromycin (Clr ), Amikacin (Am) and sensitive drugs , to observe the efficacy and safety of the treatment to MDR-TB .Results:1.The MIC of Clofazimine to Mycobacterium tuberculosis H37Rv was 0.12 ug / ml, The range of MIC to multi-drug resistant Mycobacterium TB was 0.12-1.96μg / ml.2.In the TB mice model infected with standard strains showed: Clofazimine has less anti-TB activity than Isoniazid, but it can reduce 1.8 ~ 2.9 Log 10 CFU of Mycobacterium tuberculosis in lungs, 1.5 ~ 2.5 Log 10 CFU in spleen, which has good anti-tuberculosis activity in vivo.3. In the mice model infected with resistant strain showed: after 2 months treatment, Clofazimine can reduce 2.32 Log 10 CFU of the viable count in lung, and 3.9 Log 10 CFU with 5 kinds of drugs combined chemotherapy.4.The order of tissue distribution in mice about Clofazimine is fat, spleen, kidney, liver, lung, and other organizations, Isoniazid and Pyrazinamide can improve the concentration of Clofazimine in lung tissue, after 2 months treatment with Clofazimine it is still not complete elimination in the followed 2 months. 5.In the 9th multi-drug resistant TB patients treated with Clofazimine, the course of treatment is from 3 months to 10 months, 3 of them has sputum negative after 3 months, while focus of infection were absorbed. All of them have different degrees of improvement in the clinical symptoms. Determination of plasma display larger differences individually, which has no close relationship with the effect. The main side effect is pigmentation in the face, hair and exposed skin of limbs.Conclusion:1.Clofazimine has good anti- Mycobacterium TB activity in vitro and in vivo, against the sensitive and drug-resistance TB.2.The distribution of Clofazimine is higher in fat, spleen, kidney, liver, lungs and other organization, Isoniazid and Pyrazinamide can improve the concentration of Clofazimine in lung tissue. The main reason of skin pigmentation is Clofazimine eliminated from the organization after a longer period of time since withdrawal.3.Clofazimine may be effective to the drug-resistant TB, but there is few case, we will need a large samples of clinical control study.