Following an extensive assay evaluation, we plan to move several of the viral load tests from current Roche COBAS Ampliprep platform to their new high throughput Roche cobas® 6800 platform. This move will allow a more streamlined laboratory workflow, made possible by a greater degree of automation, with the expected advantages of increased testing capacity. The viral load assays in question for the first phase of assay transfers include HIV, HBV and HCV.
In the case of the HIV viral load assay, internal evaluation showed a small overall positive bias of 0.076 log for the new automated instrument relative to the current test (the Roche TaqMan v2.0), particularly affecting low level viral loads. However, testing of NEQAS (National External Quality Assurance) samples revealed higher average precision as well as accuracy for the Roche cobas® 6800 platform relative to the existing assay.
No clinically significant performance differences are anticipated for the two other assays listed above.
A phased transfer is planned for these tests. From the 1st August 2018 we are planning to transfer the Hep B viral load assay first. For HIV and Hep C viral load, the assays are planned to transfer during the period of August 2018.
As required by UKAS, the laboratory accreditation service, we are now assessed for accreditation by individual test rather than being accredited for the overall service. When there has been a change in testing methodology or instrumentation this requires re-assessment by UKAS, and until finalised, the laboratory is not considered accredited for that particular test. This must be made clear to users on the test report. The laboratory is currently undergoing the process of assessment for this instrumentation. The laboratory will continue to perform the HIV, HCV and HBV tests in the interim but will now report the results with a disclaimer as follows “Due to a recent change in analytical platform, this test is not currently UKAS accredited.”
Please feel free to contact me if further information is required
Dr David Muir on behalf of the Department of Infection & Immunity
Direct Line: 020 331 10134
Fax: 020 331 10169