TB Breath- and Cough-testing Assays for TB Diagnosis

By Sophia Georghiou Moderator Emeritus | 29 Mar, 2017

Breath represents an attractive target for the diagnosis of pulmonary TB cases, as breath samples may contain TB bacteria or MTB-specific biomarkers and can be collected through non-invasive procedures. An additional advantage of these technologies includes the ability to diagnose pulmonary TB in HIV-infected adults and children at any level of the health system, as conventional sputum-based diagnostics show lower performance among these patient populations. The ideal breath-testing diagnostics would also differentiate patients confirmed to have active TB from those with other respiratory pathologies.

Numerous technologies with different mechanisms of TB detection in breath samples are now gaining in number (see links/attachments for a few examples). We look forward to seeing the results of early feasibility studies and independent evaluations of these technologies and to discussions surrounding the operational and performance characteristics of these assays, for TB as well as other diseases. We hope this forum will help to learn of new technologies in this field and to review and discuss recent results.

Replies

 

Dennis Camilleri Replied at 10:17 AM, 29 Mar 2017

Dear Sophia

This is an excellent discussion and thanks for starting it. For all of us working on breath analysis for TB, it is good to see that breath-based tests are now on the TB diagnostics "Radar". Thanks to FIND for agreeing to review our TB Breathalyser technology.

For more information on our TB Breathalyser please visit www.rapidbiosensor.com.
I have also uploaded an article which explains the basics of our TB antigen breath test which uses an optical interrogation process to detect the actual TB bacilli present in the cough sample. This is a POC test and it has already been field tested in India and Ethiopia on 1,000 people.

Commercially, investment is required to transfer our Breathalyser and Reader designs into production.

In future, we think that our methods can be adapted to test for other diseases including bacterial pneumonia (sometimes TB is diagnosed as pneumonia) and ultimately we want to look at bio-optical sensor design and methods for the detection of lung cancer.

We remain very positive about the use of breath technology for rapid screening of diseases.

Dennis Camilleri
CEO
Rapid Biosensor Systems Ltd
Babraham Research Campus
Cambridge, UK

Attached resources:

Wemdemagegn Tefera Replied at 1:56 PM, 29 Mar 2017

I am really impressed if this test became in use we safe more time and also solve the problem of patients who can't give sputum. My fear is how much this thing available for developing country? what we detect using this breath test? Do you have a plan giving for free to humaniterian organization?
My second question is, there were RDT for TB diagnosis. Is that still available?

Donald Catanzaro Replied at 12:10 AM, 30 Mar 2017

Hi Dennis,

The Rapid Biosensor website states the Breathalyser has been 'validated' with just under 1000 patients (in five different trials). The site states a 3-center trial was completed in 2013 achieved sensitivity/specificity of >95%.

However, the last published article on Breathalyser was in 2010 (http://bmcinfectdis.biomedcentral.com/articles/10.1186/1471-2334-10-161) and contained data from only 60 subjects with much lower sensitivity/specificity.

Does Rapid Biosensor plan on publishing the results of the five trials?

Aung Phyo Khaing Replied at 12:24 AM, 30 Mar 2017

Breath-test for TB!
Great News!
Finally, it's really available.
We're hoping to get TB-Breath analyzer commercially especially for developing countries as well as high Tb-burden countries like Myanmar.

Aung Phyo Khaing
Senior Laboratory Supervisor (TB)
National TB Control Programme
Myanmar

Dennis Camilleri Replied at 6:57 AM, 30 Mar 2017

Thank you everyone for your replies - much appreciated!

We understand that a successful rapid TB Test for use at the POC must be acceptable to the developing countries. Our optical/electronic/bio TB Breathalyser and Reader costs are very dependent on volume production. The WHO is forecasting millions of TB tests are and will continue to be required for many years and so for the projected WHO volumes, our TB Breathalyser cost is expected to be ca. $5 and our Reader ca.$1,500. These costs are realistic and even lower costs might be achievable with further production scale-up and efficiencies. Our experience for over 35 years is in optical and laser component systems design and manufacture and many of the components we use in our designs are already manufactured in very large volumes for other applications.

Our challenge is in securing volume purchase orders so we can scale-up production and so reduce our product costs and offer very competitive pricing to the End-Users.

We would very much like to discuss how we might be able to provide our TB Tests to charities when the product goes into production after we secure the required funding for this to happen.

We have additional technical papers which describe our field trials in India and Ethiopia which I will upload here. We have not published all the information before because of commercial confidentiality agreements.

Many thanks
Dennis Camilleri
CEO

Attached resources:

SUMIT MITRA Replied at 7:15 AM, 30 Mar 2017

Dear All,

The Truelab microPCR platform from Molbio has been designed for early
identification and quantitative detection of infectious agents in resource
limited settings. We have done extensive work on TB and RIF resistance
diagnosis with both the Govt. of India and FIND.



A recent large multi-centric study by the Indian Council of Medical
Research has shown that the Truenat MTB / RIF ,has excellent sensitivity
and specificity for MTB and RIF detection. Based on this, ICMR is now
working on deploying 100 such battery operated devices for pulmonary TB
detection at smear microscopy centres.



FIND is similarly conducting Indian and global studies for eventual WHO
endorsement.



We already have these devices available commercially in India and they are
typically deployed at small laboratories that, normally, would not be able
to run molecular tests. However, our sample prep and PCR devices that
require minimal training, no additional infrastructure or cold chain, now
empower these centres to provide PCR results in less than an hour. Many of
the laboratories where we do have the system also have the X-pert and LPA -
so we have a lot of comparable data



We believe that this platform will have significant impact in the fight
against TB even at Near Patient Testing (NPT) and POC settings.

Marc Tebruegge Replied at 11:49 AM, 2 Apr 2017

Dear Dennis,

Thank you for posting the abstracts related to additional studies. Importantly, these are not peer-reviewed and summarise currently unpublished work. Also, since these are only brief abstracts they lack the level of detail that would be required to interpret the study findings in a meaningful way.

I agree with Donald that it appears odd that no data related to this test have been published in a peer-reviewed journal since 2010. Notably, that paper reported the sensitivity of the assay to be below 80%.

On a side note, and please do correct me if I am wrong, this is not really a ‘breath test’, but rather a ‘cough test’, which is based on detection of MTB (via Ag85B) in aerosols. This contrasts with other studies that have aimed to detect volatile organic compounds (VOCs) in breath.

https://www.ncbi.nlm.nih.gov/pubmed/18296120

https://www.ncbi.nlm.nih.gov/pubmed/19481976

https://www.ncbi.nlm.nih.gov/pubmed/22647661

https://www.ncbi.nlm.nih.gov/pubmed/24320132

https://www.ncbi.nlm.nih.gov/pubmed/23127779

Madhukar Pai Moderator Replied at 1:36 PM, 2 Apr 2017

Hi All,

As moderators, we are concerned about product developers making claims and raising expectations without adequate, independent validation of products and relevant policy endorsements. We take this opportunity to remind all members that our community is not meant for product promotion or advertising. We ask that members not post any product information or claims regarding the performance of new technologies without accompanying publications.

Thanks

Moderators