The ultimate aim of this project is to develop diagnostic platform for viral load monitoring using whole blood samples of HIV-1 infected patients in point-of-care (POC) and resource-limited settings to be submitted for WHO prequalification and/or CE-marking. Estimation of viral load in HIV-1 patients receiving anti-viral treatment (ART) is considered the best marker for monitoring the efficacy ART, identifying and discriminating non-compliance and resistance. Currently all viral load tests are performed from plasma samples since using whole blood gives an overestimation of the viral load due to amplification of integrated HIV DNA in nucleated white blood cells. Diagnostics for the Real World (DRW) has developed the SAMBA HIV-1 Whole Blood Semi-quantitative Test (SAMBA-WBSQ) for use at POC and in resource-limited setting during Phase I. SAMBA-WBSQ uses leukodepletion to remove the nucleated cells and can distinguish between patients with viral loads above or below a predetermined clinically relevant cut-off, of 1,000 copies/ml, to aid clinicians to monitor non- compliance, treatment efficacy or treatment failure due to the development of resistance. This proposal is to further develop and optimize the SAMBA-WBSQ assay for regulatory submission to WHO prequalification and/or CE-marking.
The SAMBA Whole Blood Semi-quantitative Test is a simple, high-performance and robust nucleic acid- based point-of-care test for HIV-1 viral load monitoring. The test was developed to use whole blood sample in Phase OO to enable clinicians to monitor viral load in HIV-1 infected patients on the basis of a 1000 copies of virus as the cut-off. Availability of a whole blood viral load monitor assay at point-of-care is expected to enable a test and treat strategy and hence massively reduce loss to follow-up and increase efficacy of anti-viral therapy. The test has been evaluated in-house and in sub-Saharan Africa with patient samples and results were highly concordant with commercially available tests. In this Phase IIB continuing proposal, we will complete the development of the test and integrate it into the next generation of SAMBA instrument platform (SAMBA II) and generate the data necessary for regulatory approval of the test.
