——美国FDA批准允许第一个在美国同时检测结核菌和耐抗生素利福平上市
2013年7月25日美国食品药品监督管理局(FDA)允许Xpert MTB/RIF分析上市，第一个被FDA审评可同时检验引起结核(TB)的细菌和测定细菌是否含对治疗TB重要抗生素利福平[rifampin]耐药的检验。
这个新检验比FDA以前批准进行检测结核细菌的试验复杂性较低。检验结果包括检验TB细菌和细菌是否耐药在约2个小时就可得到结果。传统方法检验耐药TB通常需要三个月。
FDA设备和放射学中心的体外诊断和辐射卫生室主任Alberto Gutierrez，Ph.D.说：“较不复杂的检验如Xpert MTB/RIF分析可在更不同情况下使用”，“早期和迅速检验耐利福平TB可能有助于遏制耐药结核病的蔓延，一个重大的公共卫生威胁。”
TB是属于一组已知为结核分枝杆菌复合物细菌所致，这种细菌通常攻击肺。不是每一个被结核分枝杆菌感染的个体发生活动性结核，而只有活动性结核的人们可以传播至其他人。免疫系统减弱那些人是处在一旦感染细菌更高危发生结核，而如果不治疗结核可致命。世界范围有HIV艾滋人们结核是主导杀手。
结核病的常见体征和症状包括厉害的咳嗽持续三周或更长胸痛咳血，软弱和疲乏和体重减轻。
美国疾病预防和控制中心[CDC]消除结核部主任RADM Kenneth G. Castro，M.D.说：“新工具，包括迅速和准确诊断检验，在对结核病斗争进展中是至关重要的，”“早期诊断和有效治疗对药物敏感和耐药两者病例，为改善患者健康，预防疾病播散至其他人，乃至最终实现在美国消灭结核的目标都是重要的”。  
FDA通过从头[de novo]分类过程评审，一种对实质上不等同于早已合法销售的低-至中度-风险医学设备的监管途径。Xpert MTB/RIF 分析通过分类过程。
制造商提交支持从头申请，包括与确证的检验方法比较评估检验鉴定结核细菌和利福平耐药细菌株的准确性。
Xpert MTB/RIF分析由总部在加州的Cepheid of Sunnyvale制造和上市。
Xpert MTB/RIF
Automated nucleic acid amplification test (NAAT)
Product name: Xpert® MTB/RIF
Manufacturing partner: Cepheid
Stage of Development: Endorsed by WHO (2010). FIND and partners will continue extended demonstration projects and begin collecting evidence for scale up.
Level of the Health system: Peripheral laboratory, at district and sub-district level (intended for use in secure facilities with a reliable source of electricity)
Rationale: Molecular amplification is a proven technology for the detection of Mycobacterium tuberculosis. Current test methods, however, are too complex for routine widespread implementation in developing countries. Sample processing and DNA extraction adds significantly to this complexity.
The objective of this project was to develop and validate a fully-automated system that has the potential to revolutionize TB case detection by dramatically reducing the time for detection, maximizing ease of use, replacing culture methods and delivering additional data on drug sensitivity. Molecular detection of rifampicin resistance could speed targeted treatment and other measures for controlling MDR-TB.
Product description
The Xpert MTB/RIF is a self-contained and cartridge-based technological platform that integrates sputum processing, DNA extraction and amplification, TB and MDR-TB diagnosis. It has similar sensitivity to culture, targets Mycobacterium tuberculosis specifically and enables simultaneous detection of rifampicin resistance via the rpoB gene.
Training requirements are generally 1-2 days, and the 1-step external sample preparation is extremely simple. The closed system ensures that there is no risk of contamination and no requirement for bio-safety facilities. Test results can be obtained in just 90 minutes.
Assay procedure for the MTB/RIF test
Evaluation and demonstration
We assessed the performance of Xpert MTB/RIF in 1730 patients with suspected drug-sensitive or multidrug-resistant pulmonary TB in Peru, Azerbaijan, South Africa and India. Among culture-positive patients, a single, direct Xpert MTB/RIF test identified 98.2% of patients with smear-positive TB and 72.5% with smear-negative TB. The test was specific in 99.2% of patients without TB. Among patients with smear-negative, culture-positive TB, the addition of a second Xpert MTB/RIF test increased sensitivity by 90.2%.
As compared with phenotypic drug-susceptibility testing, Xpert MTB/RIF testing correctly identified 97.6% of patients with rifampin-resistant bacteria and 98.1% with rifampin-sensitive bacteria.
Over the course of 2009 and 2010, FIND, in partnership with Cepheid:
•finished a multi-centre evaluation trial and trial report for Xpert® MTB/RIF technology;
•concluded the CE-Mark technical file and registration;
•established the joint logistics team for the demonstration phase of the project;
•started the demonstration phase activities;
•completed the customer support plan; and
•submitted the required documentation to the WHO Scientific and Technical Advisory Group (WHO-STAG) in September 2010.
In December 2010, WHO endorsed Xpert MTB/RIF technology and released a roadmap to guide its rapid adoption in endemic countries.