WHO/BS/2017.2314 International Collaborative Study to Establish the 4th WHO IS for HIV-1 NAT Assays

Overview

This report describes the evaluation of candidate materials to replace the WHO 3rd International standard for HIV-1 RNA. The candidate standard, comprising a lyophilised, heat inactivated subtype B virus diluted in human citrate plasma, was evaluated in an international study alongside the current WHO 3rd International standard (NIBSC code 10/152). A liquid preparation, a positive single plasma donation and two low titre NIBSC working reagents (derived from the same stock material as the candidate IS) were also evaluated; samples were coded A to F. Twenty-one laboratories representing ten countries returned twenty-three data sets from thirteen different commercial assays and two in-house methods. Of these fifteen methods, eleven were quantitative and four were qualitative.