Alcedo Karel P, Thanigachalam Saisathya, Naser Saleh A
Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL USA.
Gut Pathog. 2016 Jun 14;8:32. doi: 10.1186/s13099-016-0115-3. eCollection 2016.
Mycobacterium avium subspecies paratuberculosis (MAP) has been implicated as an etiological agent of Crohn's disease (CD), a debilitating chronic inflammatory bowel disease. Clarithromycin (CLA), clofazimine (CLO), rifabutin (RIF) and other antibiotics have been used individually or in combinations with other drugs to treat mycobacterial diseases including CD. The treatment has varied by regimen, dosage, and duration, resulting in conflicting outcomes and additional suffering to the patients. RHB-104, a drug formula with active ingredients composed of (63.3 %) CLA, (6.7 %) CLO, and (30 %) RIF, has been recently subjected to investigation in an FDA approved Phase III clinical trial to treat patients with moderate to severe CD. In this study, we determined the efficacy of RHB-104 active ingredients against MAP strains isolated from the blood, tissue, and milk of CD patients. Based on fluorescence quenching technology using the Bactec MGIT Para-TB medium, we determined the minimum inhibitory concentration (MIC) of CLA, CLO, RIF individually and in dual and triple combinations against 16 MAP clinical strains and 19 other mycobacteria.
The MIC of all drugs against 35 different mycobacteria ranged between 0.25-20 μg/mL. However, the MIC of RHB-104 active ingredients regimen was the lowest at 0.25-10 μg/mL compared to the MIC of the other drugs at 0.5-20 μg/mL. The components of RHB-104 active ingredients at their individual concentrations or in dual combinations were not effective against all microorganisms compared to the triple combinations at MIC level. The MIC of CLA-CLO, CLA-RIF, and CLO-RIF regimens ranged between 0.5-1.25 μg/mL compared to 0.25 μg/mL of bactericidal effect of the triple combination.
The data clearly demonstrated that lower concentrations of the triple combination of RHB-104 active ingredients provided synergistic anti-MAP growth activity compared to individual or dual combinations of the drugs. Consequently, this is favorable and should lead to tolerable dosage that is desirable for long-term treatment of CD and Mycobacterium avium complex disease.
鸟分枝杆菌副结核亚种（MAP）被认为是克罗恩病（CD）的病原体，CD是一种使人衰弱的慢性炎症性肠病。克拉霉素（CLA）、氯法齐明（CLO）、利福布汀（RIF）和其他抗生素已被单独使用或与其他药物联合用于治疗包括CD在内的分枝杆菌病。治疗方案在用药方法、剂量和疗程方面各不相同，导致结果相互矛盾，给患者带来更多痛苦。RHB - 104是一种药物配方，其活性成分由（63.3%）CLA、（6.7%）CLO和（30%）RIF组成，最近已在一项FDA批准的III期临床试验中用于治疗中度至重度CD患者。在本研究中，我们测定了RHB - 104活性成分对从CD患者血液、组织和乳汁中分离出的MAP菌株的疗效。基于使用Bactec MGIT Para - TB培养基的荧光猝灭技术，我们测定了CLA、CLO、RIF单独以及两两和三联组合对16株MAP临床菌株和19株其他分枝杆菌的最低抑菌浓度（MIC）。
所有药物对35种不同分枝杆菌的MIC范围在0.25 - 20μg/mL之间。然而，与其他药物的MIC为0.5 - 20μg/mL相比，RHB - 104活性成分方案的MIC最低，为0.25 - 10μg/mL。与MIC水平的三联组合相比，RHB - 104活性成分单独浓度或两两组合时对所有微生物均无效。CLA - CLO、CLA - RIF和CLO - RIF方案的MIC范围在0.5 - 1.25μg/mL之间，而三联组合的杀菌效果MIC为0.25μg/mL。
数据清楚地表明，与药物的单独或两两组合相比，较低浓度的RHB - 104活性成分三联组合具有协同抗MAP生长活性。因此，这是有利的，应该会产生可耐受的剂量，这对于CD和鸟分枝杆菌复合群疾病的长期治疗是理想的。
