Qiagen NV announced the CE product launch of QuantiFERON-TB Gold Plus (QFT-Plus), the fourth generation of the most accurate test for detecting tuberculosis (TB) infections.

QFT-Plus builds on the legacy of QuantiFERON-TB Gold, which was the third-generation version of this important technology that has established itself as a cost-effective tool for TB infection testing with more than 20 million tests distributed worldwide since its initial launch. QFT-Plus, which was recently CE-IVD marked, is now being made available in Europe and other markets and will gradually replace the use of QuantiFERON-TB Gold, which achieved an important milestone with more than $100 million of annual sales in 2014 and becoming one of the largest products within the Qiagen portfolio.

“The launch of QuantiFERON-TB Gold Plus offers important generational improvements in our industry-leading franchise of diagnostics to detect TB infections, especially as public health experts increasingly recognise the importance of diagnosing and treating latent TB infections in the global fight against this often deadly disease,” said Peer M. Schatz, chief executive officer of Qiagen.

QFT-Plus represents a key milestone in the development of diagnostic tests for latent TB infection. For the first time, a diagnostic test offers the ability to capture a much broader picture of an individual’s immune response to TB infection. This technological advancement is critical to advancing the understanding of how the immune system reacts to TB infection, and is expected to set a new standard for future disease management. Among the many new features of QFT-Plus are:

Improved technology that delivers even higher sensitivity (ability to correctly identify those patients with disease) and specificity (ability to correctly identify all patients without disease) in patients at greatest risk for TB infection, particularly individuals co-infected with HIV/TB and other immunocompromised patients.

Advances to support research into the risk stratification of latent TB infections developing into active disease based on the first-time incorporation of CD8+ T cell response data, which provides valuable new information to researchers by measuring a broader range of immune response. Published scientific evidence underlines the future potential of CD8+ T cells in distinguishing active from latent TB, discerning recent vs. old infections, detecting TB in certain risk populations (such as HIV co-infection and young children), as well as assessing response to TB treatment.

Workflow improvements that allow for even more efficient implementation, especially in large-scale TB screening programs. These include a single-tube blood collection option as well as the ongoing use of the unique “assay in collection tube” design that allows for immediate stimulation of the blood sample, which ensures no loss of T cell activity that is critical for obtaining accurate and reliable results.

Further improvements to test reliability, consistency and performance designed to result in fewer indeterminate results and less requirements for retesting.

The launch of QFT-Plus coincides with the early stages of implementing the Post-2015 Global Tuberculosis Strategy, which was developed by the World Health Organization (WHO) and made public in October 2014. The WHO has outlined a 20-year action plan that includes new guidelines that for the first time addresses latent tuberculosis, including that health authorities in more than 100 low-incidence countries screen for people with latent TB infections and provide preventive treatment for those who are infected. Overall, a global pool of 2 billion people (or 1 in 3 people worldwide) is estimated to be infected with Mycobacterium tuberculosis, and up to 10per cent of these patients are expected to develop the active form of this airborne and highly contagious disease during their lifetime.

Leading TB control programs are turning to QuantiFERON-TB Gold to replace the tuberculin skin test (TST) because this modern test’s superior clinical performance and significantly simpler administration improves the cost-effectiveness of TB control programmes and overall healthcare. The QuantiFERON-TB Gold technology is faster, laboratory-based and quality-controlled, and more accurate than the century-old TST testing method. The global rollout of QuantiFERON-TB Gold Plus will even further enhance these significant advantages.

A particularly costly issue of TB control programs relying on skin tests is the high rate of false positives that lead to unnecessary evaluation and treatment. Recent studies show that 20-85per cent of positive TST results are negative in BCG-vaccinated persons tested with QFT. False-positive results require follow-up care such as physical examinations, x-rays and laboratory work, even for patients who turn out to have no TB infection adding unnecessarily to patient risk from unneeded treatment and healthcare expenses. Positive readings provided by QuantiFERON-TB technology, on the other hand, are up to 99per cent accurate.

Screening with QuantiFERON-TB Gold also reduces false-positive readings caused by common environmental mycobacteria exposure and by the Bacille Calmette-Guérin (BCG) vaccination, which children in many countries receive. The WHO post-2015 strategy supports use of the BCG vaccine in high-burden countries, but the TST is especially inaccurate in BCG-vaccinated persons because of cross-reacting antigens. QuantiFERON-TB Gold does not cross-react with the BCG vaccine.

QFT-Plus is the latest product introduction involving the proprietary QuantiFERON technology, which offers a unique and efficient approach to disease detection. QuantiFERON is able to provide objective information on the activity of cell-mediated functions of the immune system by measuring the release of interferon-gamma in response to specific antigens or proteins contained in whole blood samples through a simple, highly automated process. QuantiFERON is in particular unique in its ability to detect presymptomatic infections that cannot be discovered using standard diagnostic technologies. In addition to the TB infection tests, QIAGEN also offers a CE version of QuantiFERON-CMV, a whole blood assay to monitor changes in cell-mediated immunity to cytomegalovirus (CMV), which is the most common and problematic viral infection in solid organ transplant recipients. Additional assays involving QuantiFERON are in development.