John Frater University of Oxford The UNICORN study - Whole blood finger-prick sampling for rapid and convenient PoC HIV viral load measurement Poster MOPEB0264
 Monday, 24 July 2017, 12:30 – 14:30 John Frater University of Oxford

Background PoC HIV diagnostics is widely available PoC HIV plasma viral load (pVL) is not PoC pVL testing would revolutionise the way we manage HIV: In high burden settings In low resource, low infrastructure settings For clinical trials requiring rapid and regular monitoring Eg Treatment Interruption studies for cure interventions

Rationale: the PITCH study Prospective Interruption of Therapy Towards a Cure for HIV (PITCH) Aim: To prospectively study mechanisms of post-treatment control after ART in Primary HIV Infection N=20; Pilot study Intensively Monitored Treatment Interruption (IMTI) IMTI Protocol involves pVL testing up to 3 times per week HOW BEST TO DO THIS?

Protocol dilemma: Quantitative or Qualitative monitoring?? More data ?too much data Only available from plasma Needs central lab 1ml plasma Qualitative Simple read-out Detectable:Yes/No Need to define cut-off Might be able to run from whole blood ? Could be done from a fingerprick

UNICORN ‘Use of Needleprick Investigation to Collate Objective Rebound Notifications’ Can we adapt Xpert HIV VL and HIV Qual cartridges for PoC needlestick pVL measurement? Recruited participants at St Mary’s Hospital, London N=40 20 WITH UNDETECTABLE pVL – all <20 copies/ml 20 WITH DETECTABLE pVL – wide range of values

Study Protocol: Each Participant x1 x4 4 CARTRIDGES: 100ul WB Finger-prick sample SPIN PVL assay Roche Taqman Certified clinical lab HIV-1 Qual x2 HIV-1 Viral Load x2

The ‘SPIN’ step Microcentrifuge Portable Cheap 3 minute spin

Finger-Prick Sample Prep HIV-1 Qual Cartridge HIV-1 Viral Load Cartridge 100µl blood ADD TO 1000µl buffer ADD TO CARTRIDGE 100µl blood ADD TO 100µl PBS SPIN for 3 mins REMOVE 100µl 1000µl buffer ADD TO CARTRIDGE 100µl blood ADD TO 900 µl PBS ADD TO CARTRIDGE 100µl blood ADD TO 1000 µl PBS in EPPENDORF SPIN for 3 mins REMOVE 1000µl ADD TO CARTRIDGE

WHAT ABOUT FOR DETECTABLE VIRAEMIA?

Range of Detectable Viraemia (n=20) Mean 95,219 copies/ml Range 33-1,514,378 copies/ml

What does this tell us? (Part 1) Can’t do pVL from WB using standard protocols Introducing spin allows accurate indentification of undetectable viraemia Introducing spin impacts sensitivity for quantification of detectable viraemia With HIV Viral load assay a finger-prick PoC approach Can we still use this protocol, accepting a higher LLD?

Analysis according to Roche pVL

Analysis according to Roche pVL SPIN STEP PRESERVES CONCORDANCE WITH ROCHE AT PVL > 1000 COPIES/ML

Excellent concordance for all pVL >1000 copies/ml

What does this tell us? (Part 2) Can’t do pVL from WB using standard protocols Introducing spin allows accurate identification of undetectable viraemia Introducing spin impacts sensitivity for quantification of detectable viraemia For UNDETECTABLE viraemia: PoC approach gives 100% agreement with Roche For DETECTABLE viraemia: PoC approach is accurate for pVL >1000 copies/ml

Acknowledgements Participants of UNICORN Peter Medawar Building, Oxford Jodi Meyerowitz Imperial College, London Heather Lewis Kristen Kuldanek John Thornhill Panagiotis Pantelidis David Muir Sarah Fidler Cepheid Georgina Timson Alice Bonnissent Poster MOPEB0264
 Monday, 24 July 2017, 12:30 – 14:30 www.cherub.uk.net Twitter: @ukcherub