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Originally Published IVD Technology March 2005

Tenth Anniversary

Top 10 IVD Products and Technologies

The following list presents 10 of the top IVD products and technologies that IVD manufacturers have released or further developed during the past 10 years. This list is based on responses generated from a survey taken by IVD Technology’s editorial advisory board and reader board members. In this survey, the board members were asked to state what they thought were the most important IVD products and technologies that have had the greatest influence on the IVD industry during the past 10 years. Of their responses, the following IVD products and technologies represent the ones that were most frequently mentioned by the board members.

Cardiovascular assays

The NT-proBNP test by Dade Behring Inc. (Deerfield, IL).

Troponin assays have become the gold standard marker for acute myocardial infarction diagnosis and for risk stratification in acute coronary syndromes. The introduction of high-sensitivity C-reactive protein (hsCRP) assays has significantly increased the understanding of the role of inflammation in cardiovascular disease. The hsCRP assays have also improved clinicians’ abilities to assess an individual’s risk of future cardiovascular disease and target more-appropriate therapies. In addition, the importance of the B-type natriuretic peptide (BNP) assays and their role in ruling out congestive heart failure cannot be overlooked.

Multiplex systems

The GeneXpert system by Cepheid (Sunnyvale, CA).

Multiplexing allows scientists to collect meaningful, trustworthy, and accurate data, with greater quality control than individual tests can provide. By their very nature, separate tests are at risk of having different variables introduced that could compromise the results. In addition, such tests cannot effectively demonstrate what happens in a living system in which each molecule influences the expression, level, and stability of each other. Multiplexing enables multiple proteins, nucleic acids, etc., to be analyzed and measured essentially in their natural state, under controlled conditions in which every individual test is treated exactly the same way.

Her-2/neu tests

The PathVysion test by Vysis Inc. (Downers Grove, IL).

There are two tests for determining Her-2 status: immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). IHC is a protein-based test that is used to determine the total amount of Her-2 protein receptors on the surface of the cell. To do this, the surface of the cell is stained with an antibody. FISH is a gene-based test that measures the number of Her-2 genes in a cell. The FISH test highlights the Her-2 genes inside the cell, making them appear fluorescent so they may be accurately counted.

Noninvasive glucose monitors

The GlucoWatch G2 Biographer by Cygnus Inc. (Redwood City, CA).

One of the new technologies for glucose testing that avoid fingersticks is based on near-infrared spectroscopy. There have been increasing numbers of reports in the scientific literature on the challenges, strengths, and weaknesses of this and other new approaches to testing glucose without fingersticks. FDA has approved one minimally invasive meter and one noninvasive glucose meter. They are used to obtain additional glucose values between fingerstick tests. Both devices require daily calibration using standard fingerstick glucose measurements and remain the subject of continuing studies to find how they are best used as tools for diabetes management.

Microarray systems

The AmpliChip CYP450 by Roche Diagnostics (Indianapolis).

Microarrays have revolutionized the understanding of the molecular features and function of the human genetic system. Microarrays can be designed for analyzing gene expression patterns (which genes are turned on or off in a given tissue or disease state), confirming gene sequences (which molecular building blocks or base pairs are present in a sample, potentially important information for identifying specific variants of an infectious disease), or genotyping (determining which specific genetic variations are present in the individual or infectious agent).

The Hybrid Capture 2 test by Digene Corp. (Gaithersburg, MD).

Nucleic acid amplification tests for STDs

A significant breakthrough in nucleic acid testing for STDs was the development of target and signal amplification methods that improved sensitivity and specificity. Tests based on enzymatic target amplification increase target molecules to levels that can be easily detected using various reporter systems. Signal amplification methods enhance the signal without changing the number of target molecules.

Pap smear tests

Test slide results from the ThinPrep Pap test by Cytyc Corp. (Marlborough, MA).

The significant limitations of the conventional Pap smear include limited sensitivity and a significant proportion of inadequate specimens. Consequently, new technologies, such as liquid-based cytology methods, have been developed to address such limitations. Such tests have proven to be significantly more effective than the conventional Pap smear for detecting cervical abnormalities and have demonstrated a wide range of clinical benefits, including increased disease detection, reduction of equivocal diagnoses, improved specimen adequacy, cost-effectiveness, and the ability to perform additional tests out of the same vial.

Polymerase chain reaction (PCR) technologies

The LightCycler system by Roche Diagnostics (Indianapolis).

The immediate and far-reaching implications of PCR cannot be overstated. Using PCR, scientists can take a specimen containing a minute amount of genetic material, copy a selected region from it over and over, and within hours, generate a sample sufficient to perform a variety of tests. PCR is also very versatile. Many types of samples (e.g., blood, skin cells, saliva, hair) can be analyzed for nucleic acids. The main criterion for any sample used for PCR is that it must contain the DNA strand encompassing the region to be amplified.

Rapid HIV tests

The OraQuick Advance Rapid HIV-1/2 test by OraSure Technologies (Bethlehem, PA).

In November 2002, OraSure (Bethlehem, PA) received FDA approval for the fingerstick whole blood version of its OraQuick Rapid HIV-1 antibody test. This test became the first FDA-approved, rapid point-of-care HIV-1 test available in the United States. In January 2003, FDA approved a waiver under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) for the test, making it available for use by all CLIA-registered labs in the United States. The test then received FDA approval for oral fluid and plasma applications in March 2004.

The Procleix WNV assay being run on the Procleix Tigris system by Gen-Probe Inc. (San Diego).

West Nile Virus (WNV) tests

Nucleic acid testing allows significantly earlier detection of WNV infection than another testing method that uses immunoglobulin (IgM) antibodies. Such testing methods are not suitable for screening donated blood because they require antibodies or viral proteins to reach detectable levels. Newer WNV tests that have been developed facilitate earlier detection by incorporating methods for extracting, amplifying, and detecting low levels of viral RNA. However, nucleic acid tests heighten diagnostic sensitivity, but often at the cost of specificity. Therefore, an appropriate confirmatory test, likely to be based on an IgM testing platform, may be needed.

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