Cellestis Receives FDA Approval For Blood Test For Detecting Tuberculosis
Physicians & TB controllers around the country can now quickly and accurately detect M. tuberculosis infection with today's U.S. Food and Drug Administration (FDA) approval of QuantiFERON-TB Gold In-Tube (QFT). This blood test detects cellular immune responses to proteins specifically associated with tuberculosis (TB) infection. It replaces the original QuantiFERON-TB Gold, and offers the same specificity and accuracy advantages. In addition, the new In-Tube format, already widely used in Europe and Asia, simplifies testing and fits with existing laboratory equipment, giving convenient TB testing from Kalispell to Key West. Both tests replace the 100-year-old tuberculin skin test (TST).
CEO of Cellestis, Dr Tony Radford, comments, "With the In-Tube system, the blood incubation requires virtually no labor and no set-up time. It makes a QFT test as simple as a routine antibody test and extends the availability of QFT testing by streamlining logistics to allow the initial incubation process to be done almost anywhere. The FDA approval now permits our U.S. customers to enjoy the cost-savings, and quality result of In-Tube, as well as a better process fit with hospitals and labs."
The TST, which involves a crude tuberculosis extract injected into the skin, is over 100 years old. Despite its limitations, it is widely used for detecting TB infection. Significantly, the TST is often confounded in persons vaccinated with Bacillus Calmette-Guerin (BCG) (TB vaccination), as well as those exposed to some environmental bacteria, giving many people a false- positive TST results. The TST has poor reproducibility and requires two patient encounters; one to inject the subject and a second, 2-3 days later, to read the inflammation it may produce. Measuring the inflammation requires trained medical personnel but is still highly subjective, and is notorious for inaccuracy. This leads to poor use of valuable medical resources, and the need for a second clinic visit means many people fail to have their TST read.
QFT is supported by data from over 100 clinical publications, requires a single blood test, and gives objective and reproducible results. The In-tube format simplifies testing logistics, enabling remote location blood collection. It measures immune responses to peptides that simulate M. tuberculosis proteins, which are not present in the BCG vaccine or most non- tuberculosis mycobacteria. Thus, QFT is 99% specific and a positive test result is strongly predictive of true infection with M. tuberculosis. As people suspected of TB infection are normally recommended for TB therapy, which carries risks of liver toxicity and nerve damage, use of the highly specific QFT test will reduce unnecessary therapy and overtreatment, therefore having significant medical benefit.
QFT provides a new standard for TB control and gives the US TB control community an effective, reliable and accurate screening method. In addition, QFT yields dramatic cost savings in medical staff time and by eliminating the common false-positive results of the TST. For TB control programs across the nation, QFT can relieve the medical, logistic, administrative and cost burden associated with TB testing compliance.