Presentation on theme: "Angela M. Starks, Ph.D. Microbiologist, Laboratory Capacity Team Laboratory Branch, Division of Tuberculosis Elimination CTCA Conference April 28, 2011."— Presentation transcript:
Angela M. Starks, Ph.D. Microbiologist, Laboratory Capacity Team Laboratory Branch, Division of Tuberculosis Elimination CTCA Conference April 28, 2011 National Perspective on Molecular Diagnostics for TB National Center for HIV/AIDS, Viral Hepatitis, STD & TB Prevention Place Descriptor Here
Eliminate U.S. Tuberculosis Find and treat latent M. tuberculosis infection Interrupt transmission Reduce diagnostic delay Provide prompt effective treatment Investigate recent transmission, using outbreak investigation and genotyping Global engagement 1999 Plan* directs us “to improve laboratory capacity for identifying mycobacterial species and conducting real-time drug susceptibility testing” 2 *Tuberculosis Elimination Revisited
3 Recommendations for Diagnostic Laboratory* Accurate, reliable, and prompt laboratory services, coordinated with providers Laboratory capacity must be rapidly enhanced, both in the United States and worldwide Laboratory methods and reporting, especially for susceptibility to second-line drugs, should be standardized through expert consensus Rapid tests of newer molecular methods must be evaluated promptly to determine their feasibility *Original language modified to fit the slide Click here
Selected 2009 Federal TB Task Force Recommendations* Objective 6.1. Improve ability of laboratories to identify and report drug-resistant M. tuberculosis Encourage use of state-of-the-art rapid tests through focused funding Develop bank isolates for proficiency testing and research Objective 8.1 Develop strategies for expedited evaluation and implementation of new rapid methods for laboratory confirmation of tuberculosis and identification of drug-resistance Expand genomic characterization to discover new markers of second-line drugs resistance Evaluate and deploy rapid culture-based and molecular drug-susceptibility testing methods Discuss with FDA criteria required for approval of new tests 4 *Original language modified to better fit the slide
Use of Molecular Diagnostics for TB Three areas in laboratory workflow Direct Detection of Mycobacterium tuberculosis complex (MTBC) in a clinical specimen by nucleic acid amplification (NAA) testing Are MTBC bacilli detected? Are mutations associated with drug resistance present? Identification of acid-fast bacilli from a positive culture Are MTBC bacilli detected? If not MTBC, are common nontuberculous mycobacteria isolated? Rapid detection of resistance associated mutations in isolate from a positive culture Is the MTBC isolate potentially multi-drug resistant (MDR)? Are mutations associated with resistance to second-line drugs present?
What nucleic acid amplification tests are being used for direct detection? FDA-approved for use with respiratory specimens Amplified M. tuberculosis Direct Test® (MTD): Gen-Probe, Inc. Non-FDA approved commercial tests Hain Lifesciences Line Probe Assay GenoType ® Mycobacteria Direct GenoType MTB-DRplus Innogenetics InnoLipa Assay INNO-LiPA Rif. TB Cepheid GeneXpert ® MTB/RIF assay Laboratory developed tests (e.g., real-time PCR assays including molecular beacons) Off-label use of FDA-approved tests
Methods for NAA Testing Used in Public Health Laboratories, 2009 PHLs awarded funds through DTBE Cooperative Agreement
FDA Regulatory Considerations Molecular diagnostics are defined as in vitro diagnostic devices (IVD) IVD are defined as an “instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related article…intended for use in the diagnosis of disease or other conditions, or in the cure, treatment, or prevention of disease, in man” (section 321 (h) Federal Food, Drug, and Cosmetic Act)
FDA Regulatory Considerations (2) IVD are classified into one of three regulatory classes (Class I, II, or III) based on the level of control needed to ensure safety and effectiveness of the device Risk or consequence of a false result a determining factor for classification Commercial distribution of IVD for diagnostic use requires FDA approval (Class III) or FDA clearance (Class I, II) Device classification dictates the type of regulatory submission required Premarket notification 510 (k)—FDA cleared Premarket approval (PMA)—FDA approved Burd,. Validation of Laboratory-Developed Molecular Assays for Infectious Diseases. 2010. Clinical Microbiology Reviews. 550-576.
Regulatory Process for Molecular TB Diagnostics IVD for the detection of M. tuberculosis or mutations associated with drug resistance from a clinical specimen are classified as class III (1994) At the time, h ighest risk classification based on health threat of false- negative and risk to patient or community “Devices are usually those that support or sustain human life, are of substantial importance in preventing impairment of human health, or which present a potential, unreasonable risk of illness or injury” (section 513(a)(1)(C) of the Federal Food, Drug, or Cosmetic Act) Class III devices require PMA o Includes a scientific evaluation of data demonstrating reasonable assurance of safety and effectiveness o Inspection of manufacturer for good manufacturing practices Burd,. Validation of Laboratory-Developed Molecular Assays for Infectious Diseases. 2010. Clinical Microbiology Reviews. 550-576.
New Tests for Rapid Identification of M. tuberculosis and Detection of Resistance–associated Mutations August 2009, proposed to DTBE Laboratory Branch External Peer Review Panel, to partner with industry and engage FDA to develop strategies to expedite evaluation and implementation of promising technologies June 2010, “Advancing the Development of Diagnostic Tests and Biomarkers for Tuberculosis,” a public workshop jointly sponsored by CDC, FDA, and NIH 11
CDC participating in an inter-agency discussion around risk mitigation of new diagnostic assays for TB June 28–30, Workshop on “Tuberculosis and HIV Diagnostics in Adult and Pediatric Populations” June 29, public meeting of the Microbiology Devices Panel of the Medical Devices Advisory Committee will discuss and make recommendations regarding possible reclassification Federal Register notification March 16, 2011 Federal Register notification March 16, 2011 12 New Tests for Rapid Identification of M. tuberculosis and Detection of Resistance–associated Mutations (2)
CDC Role in Improving the Capability of Laboratories to Identify and Report Drug-resistant M. tuberculosis Yearly, CDC provides 7.6 million USD through cooperative agreements for laboratory enhancement to 64 jurisdictions Provide isolates through MPEP for DST proficiency testing Provide DNA for validation of molecular assays for detection of drug-resistance One-time, DTBE distribution of 3 million USD to PHLs through Association of Public Health Laboratories supplement for programmatic intervention to increase patient access to molecular diagnostics, FY2010 13
Changes in Methodology as Described in APHL Funding Requests
Cepheid GeneXpert® System and MTB/RIF Assay Research and development was public-private investment USG (DoD, NIH—initial platform development focused on detection of anthrax) Foundation for Innovative Diagnostics (Gates funded) University of Medicine and Dentistry of New Jersey Cepheid Fully integrated sample preparation, amplification, and detection for real-time results in 2 hours Received European Union CE* marking Recently endorsed by WHO based in part on scientific review, using GRADE system * "Conformite Européenne” 15
WHO Recommendations * Xpert MTB/RIF should be used as the initial diagnostic test in individuals suspected of having MDR TB or HIV-associated TB (Strong recommendation) Xpert MTB/RIF may be considered as a follow-on test to microscopy in settings where MDR TB or HIV is of lesser concern, especially in further testing of smear-negative specimens (Conditional recommendation acknowledging major resource implications) * Policy Guidance on Xpert MTB/RIF for rapid diagnosis of tuberculosis and multidrug- resistant tuberculosis. Geneva, World Health Organization, 2011 (in press)in press 16
CDC Response to Xpert MTB/RIF Increasingly broad USG involvement, including USAID and PEPFAR, in the implementation and evaluation in high burden countries Advising WHO Collaboration in PMA Study DTBE’s Clinical Research Branch TB Trials Consortium DTBE’s Laboratory Branch NIH and its AIDS Clinical Trials Group Exploring CDC-sponsored Investigational Device Exemption-based operational study of Xpert MTB/RIF U.S. implementation Assessing impact of molecular diagnosis on National TB Surveillance System 17
Programmatic Support, Molecular Detection of Drug Resistance (MDDR) DTBE Laboratory Branch implemented in September 2009 (CLIA compliant) Clinical service to domestic TB control programs and clinicians Rapid confirmation of RMP-resistant and MDR TB Laboratory testing data available about second-line drug resistance New technologies may fill the role in the future but demand exists now DNA sequencing, ABI 3130xl
MDDR Service, Phase II Provide rapid direct detection of drug resistance to rifampin and isoniazid from patient specimens Pyrosequencing–based assay is currently being validated Processed sediments provided by state public health laboratories for validation study (de-identified remnants) Proposed start date, summer of 2011 22
Additional Programmatic Support Dear colleague letter sent to public health laboratory and TB control programs February 2011 Brief technical guidance recommending continued provision of conventional DST along with molecular testing Rapid molecular assays are supplemental not a replacement test Encouraged consideration of additional molecular testing (e.g., MDDR) when molecular assay indicates resistance to rifampin Encouraged rapid communication of preliminary molecular results APHL collaboration to target generalized strengthening of the national tuberculosis laboratory system Regional trainings to include laboratorians from all sectors, TB control, and clinicians Core curriculum to provide continued education of laboratory workforce
Summary Issues Imperative for advancing new diagnostic tools CDC programmatic support through cooperative agreements, supplements, partnership, and MDDR service Xpert MTB/RIF CDC, TBTC and DTBE Laboratory Branch participation in PMA study along with NIH, ACTG CDC operational study (no funds, consent) Risk mitigation, public meeting June 29 Related issues for other diagnostic tests 24
For more information please contact Centers for Disease Control and Prevention 1600 Clifton Road NE, Atlanta, GA 30333 Telephone, 1-800-CDC-INFO (232-4636)/TTY: 1-888-232-6348 E-mail: firstname.lastname@example.org Web: www.cdc.gov The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. Acknowledgements Michael Iademarco, MD, MPH Tracy Dalton, PhD Beverly Metchock, DrPH, D(ABMM) Mitch Yakrus, MS Texas, Maryland, Florida, and Alabama public health laboratories National Center for HIV/AIDS, Viral Hepatitis, STD & TB Prevention Place Descriptor Here