Introduction and Background of the Project

Introduction

Tuberculosis (TB) remains one of the leading infectious diseases in the world, having caused 1.4 million deaths (including 208 000 with HIV) in 2019. In the absence of a simple, cost effective and reliable rapid diagnostic test (RDT) around 30% of the annual 10 million new TB cases remained undiagnosed. This is primarily due to the lack of a non-sputum based rapid diagnostic test for the detection of TB biomarker in the biological sample like urine.

The rapid diagnostic test co-developed by Asahi Kasei Corporation (Japan) and Biopromic (Sweden) detects picogram amount of Lipoarabinomannan (LAM) TB biomarker in the urine of TB patients irrespective of HIV infection in timely manner with high accuracy.

Project objective

The main objective is to validate a Rapid Diagnostic Test which is currently developed by Asahi Kasei and Biopromic for diagnosis of tuberculosis in TB patients irrespective of HIV status. Moreover, the test should meet the WHO TPP criteria.

Project design

Asahi Kasei´s and Biopromic´s RDT test will be evaluated by analysis of more than 1000 well-characterized clinical samples collected from South Africa and Uganda to determine the accuracy of the test.

How can your partnership (project) address global health challenges?

The inability to diagnose tuberculosis rapidly is a major cause of prolonged sickness and death. Early detection of TB cases and treatment is the key to stop TB spreading.    

The Asahi Kasei´s and Biopromic´s test will provide affordable, simple and accurate diagnostic tests that allows the medical staff to perform the test on site without the need of centralized lab seething.

What sort of innovation are you bringing in your project?

The only available non-sputum test in the market has not enough sensitivity to be used as a reliable test for diagnosis of TB patients especially in the TB population without HIV infection. The Asahi Kasei´s and Biopromic´s RDT test will apply a novel proprietary technology regarding sample preparation and labeling particles that allows LAM TB biomarker detection at lower picogram level, which is 100 times higher than the only test available so far.

Role and Responsibility of Each Partner

Biopromic will be responsible for the production of specific monoclonal antibodies, purified biomarker and reagents for the enrichment of the LAM biomarker at large scale that requires for generation of a substantial numbers of RDT test to perform the evaluation studies. Biopromic will also be responsible for the collection of the clinical samples in coordination with the sites in Africa. Asahi Kasei will be responsible for generation and optimization of the RDT test.

Final Report

1. Project objective

Current diagnostic tests for tuberculosis are not adequate, tedious, and expensive. In addition, they employ sputum samples as matrix leaving behinds HIV/TB coinfected people and children who cannot generate sputum for analysis. Moreover, sputum-based test cannot diagnose patient with extrapulmonary tuberculosis (tuberculosis outside lungs) which account for 17% of the total Tb patients, or 40-60% of TB patient coinfected with HIV.

In our project, we have developed a non-sputum (urine) based lateral flow assay (LFA) for the diagnosis of active tuberculosis in all TB patients’ categories irrespective of the site of infection i.e., pulmonary and extrapulmonary tuberculosis in children and adults with and without HIV coinfection. The test is a simple lateral flow device like the known pregnancy test that generate results in less than one hour and at a low cost.

2. Project design

During this project, several LAM (tuberculosis biomarker) specific antibodies were generated and used to establish several LFA prototypes with high sensitivity. Urine collected from tuberculosis suspect individuals processed by a simple means and then applied on the LFA device. Presence of LAM in the urine samples results in a distinct colored band on the LFA device as an indicative of active tuberculosis.

3. Results, lessons learned

In this project, we analyzed 1080 well-characterized urine samples collected from 5 high tuberculosis endemic areas in South Africa and Uganda. For the sake of comparison, the urine samples were tested in parallel with Alere/Abbott LAM test, the only test endorsed by WHO for the diagnosis of active TB in HIV infected people. Our test showed 38% higher sensitivity than the Alere LAM test in HIV+ infected TB patients (73% compared to 35%). The sensitivity of the Alere TB LAM test in HIV negative is very poor ranging from 0-16%. The sensitivity of our test in HIV negative TB patients was 57% which means 41% higher sensitivity than Alere LAM test.

Another test under development is Fujifilm TB LAM test. Since this test is not available in the market, we haven’t been able to perform head-to-head comparison.

However, in a small cohort consisting of 22 patients in South African, the Fujifilm LAM test was compared with our (Biopromic and Asahi Kasei test). The sensitivity of our test was 50% higher than Fujifilm LAM test (75% versus 25%) in tuberculosis patients without HIV infections, and 33% higher the Fujifilm LAM test (83% versus 50%) in TB/HIV coinfected patients.

In yet another study, we have analyzed and compared fresh urines with frozen urines and found 10% improvement in both sensitivity and specificity.

In this project, we have learned that it could be a variation in the test accuracy among geographically distinct TB endemic area, and fresh urine samples slightly contributes to the improvement of the test accuracy.