New research suggests potential for additional clinical utility of QIAGEN’s QuantiFERON-TB Gold Plus
Apr 12 2017

New research suggests potential for additional clinical utility of QIAGEN’s QuantiFERON-TB Gold Plus

Findings indicate increased specificity in low-risk populations and potential for monitoring tuberculosis treatment

Hilden, Germany, and Germantown, Maryland, April 12, 2017 – QIAGEN N.V. (NASDAQ: QGEN; Frankfurt Prime Standard: QIA) today announced that two peer-reviewed studies indicate the potential additional clinical value for QuantiFERON-TB® Gold Plus (QFT-Plus®), the fourth-generation test using enhanced QuantiFERON technology to detect latent tuberculosis (TB) infection. Both studies focus on potential benefits of novel CD8+ T-cell stimulating antigens contained in QFT-Plus. A study at the Stanford University School of Medicine is the first publication describing the performance of QFT-Plus in healthcare workers, while a study at Japan’s National Hospital Organization Hokkaido Medical Center provides the first evidence for QFT-Plus as a potential monitoring aid during treatment of active TB. 

“These studies add to a growing body of clinical evidence on QuantiFERON-TB Plus, suggesting added utility for our novel CD8+ T-cell technology. We have introduced QFT-Plus in more than 60 markets since 2015 to aid in tuberculosis control by screening at-risk populations for latent TB infection,” said Dr. Masae Kawamura, Senior Director, TB Medical and Scientific Affairs, at QIAGEN. “The unique ability of QFT-Plus to measure CD8+ immune response has led the World Health Organization to suggest that the new test offers potential for identifying patients at greater risk of progressing to active TB. A number of clinical studies are underway to explore broader applications based on the CD8+ capability, although regulatory approvals to date focus on the effectiveness of QFT-Plus in detecting latent TB infection.”

As the world’s leading interferon gamma release assay (IGRA), QuantiFERON technology is a faster, less labor-intensive and more accurate latent TB test compared to the century-old tuberculin skin test. QuantiFERON-TB® Gold (QFT®), the third-generation assay, measures the immune response with antigens that primarily elicit a CD4+ T-cell response. A positive result indicates infection, and guidelines recommend treatment of latent TB to prevent progression to active disease. QuantiFERON-TB Gold Plus, the fourth generation, builds on this foundation by adding proprietary CD8+ antigens, as well as workflow improvements.

In the Stanford study, published by the Journal of Clinical Microbiology, researchers screened 989 U.S. healthcare workers (HCWs) at low risk for tuberculosis infection with both QFT-Plus and QFT. Comparing results showed agreement of 95.6% between the two tests. Researchers found they could reduce the positivity rate in risk-free HCWs population by applying a “conservative” reading where only a positive QFT-Plus result in both antigen tubes counted as a positive, thereby utilizing a positive immune response to both the CD4+ and CD8+ antigens to confirm a positive result. The authors say that using QFT-Plus with a double-positive interpretation strategy could increase specificity in screening low-risk healthcare workers, limiting unnecessary follow-up treatment and reducing costs of TB management.

In the Japanese study, a research letter published by the European Respiratory Journal, the Hokkaido Medical Center in Sapporo used QuantiFERON-TB Plus to assess 38 patients being treated for active pulmonary TB. They were tested at the start of their tuberculosis treatment, and after three and six months. Using QFT-Plus, the researchers compared measurements of the patients’ CD4+ (TB1 antigen tube) and CD8+ (TB2-TB1 antigen tubes) responses and found that both declined significantly in the first three months. Between three and six months, the CD8+ response was more effective at measuring further containment of the infection. The researchers suggest the potential use of QFT-Plus to monitor the ongoing progress of TB treatment.

Tuberculosis is a contagious bacterial infection spread primarily through the air, such as by coughing from patients with the active pulmonary form of TB. About 10.4 million new cases of active TB disease and 1.8 million deaths were reported by the World Health Organization for 2015. About one-third of people worldwide have latent TB infection, in which the bacterium infects a person but does not cause symptoms. About 5-10% of those individuals with latent TB, if untreated, will progress to active disease – so screening and treatment for latent infection play a growing role in global tuberculosis control efforts.

QIAGEN partners with governments and health organizations around the world to fight tuberculosis and continues to develop innovative new technologies. Use of QuantiFERON-TB screening solutions continues to grow rapidly, with a total of more than 30 million tests conducted so far. QFT-Plus is approved with CE-IVD marking in Europe and has been submitted to the U.S. Food and Drug Administration (currently available for research use only in the United States). To learn more about QFT and QFT-Plus, please visit



QIAGEN N.V., a Netherlands-based holding company, is the leading global provider of Sample to Insight solutions that enable customers to gain valuable molecular insights from samples containing the building blocks of life. Our sample technologies isolate and process DNA, RNA and proteins from blood, tissue and other materials. Assay technologies make these biomolecules visible and ready for analysis. Bioinformatics software and knowledge bases interpret data to report relevant, actionable insights. Automation solutions tie these together in seamless and cost-effective workflows. QIAGEN provides solutions to more than 500,000 customers around the world in Molecular Diagnostics (human healthcare), Applied Testing (forensics, veterinary testing and food safety), Pharma (pharma and biotech companies) and Academia (life sciences research). As of December 31, 2016, QIAGEN employed approximately 4,700 people in over 35 locations worldwide. Further information can be found at

Certain statements contained in this press release may be considered forward-looking statements within the meaning of Section 27A of the U.S. Securities Act of 1933, as amended, and Section 21E of the U.S. Securities Exchange Act of 1934, as amended. To the extent that any of the statements contained herein relating to QIAGEN's products, collaborations markets, strategy or operating results, including without limitation its expected adjusted net sales and adjusted diluted earnings results, are forward-looking, such statements are based on current expectations and assumptions that involve a number of uncertainties and risks. Such uncertainties and risks include, but are not limited to, risks associated with management of growth and international operations (including the effects of currency fluctuations, regulatory processes and dependence on logistics), variability of operating results and allocations between customer classes, the commercial development of markets for our products to customers in academia, pharma, applied testing and molecular diagnostics; changing relationships with customers, suppliers and strategic partners; competition; rapid or unexpected changes in technologies; fluctuations in demand for QIAGEN's products (including fluctuations due to general economic conditions, the level and timing of customers' funding, budgets and other factors); our ability to obtain regulatory approval of our products; difficulties in successfully adapting QIAGEN's products to integrated solutions and producing such products; the ability of QIAGEN to identify and develop new products and to differentiate and protect our products from competitors' products; market acceptance of QIAGEN's new products and the integration of acquired technologies and businesses. For further information, please refer to the discussions in reports that QIAGEN has filed with, or furnished to, the U.S. Securities and Exchange Commission (SEC).


Share this page