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1 Who believes in oral HIV point-of-care tests? A summary of 3 years experience and more than 2000 OraQuick ADVANCE tests N Garrett, J Saunders, K Moir, J Zelin, C Estcourt On behalf of North East London HIV & Sexual Health Clinical Network Overview FDA approval and CDC study (Delaney et al. 2006) 9 US cities 99.1% sensitivity, 99.6% specificity Phase 1 of validation study (n=1001) (Zelin et al. 2008) Recruitment from 4 North East London GUM clinics Only the blood EIA test result is given to participants approval Delaney KP, et al. Performance of an oral fluid rapid HIV-1/2 test: experience from four CDC studies. AIDS Aug 1;20(12): Zelin J et al. An Evaluation of the performance of Oraquick ADVANCE Rapid HIV-1/2 Test in a high-risk population attending genitourinary medicine clinics in East London, UK. Int J STD & AIDS 2008;19:

2 Overview Phase 2 of validation study (n=526) Result of POCT given and confirmatory EIA performed Roll out to routine clinical practice (n=1337) OraQuick ADVANCE for all patients in high prevalence risk groups with confirmatory EIA for reactive tests Multi-site study Homerton University Hospital Newham University Hospital 7.99 per per 1000 Barts Hospital The Royal London 7.99 per per 1000

3 Study methods Cross-sectional prevalence study High-risk population MSM Country of origin prevalence >1% Recruitment by clinic staff, consenting and testing by health advisors Anonymous patient questionnaires East London & the City Ethics Committee approval OraQuickADVANCE Rapid HIV-1/2 Antibody Test Test kit Swab gums Mucosal transudate Test reagent Result

4 Results - Phase 1 HIV Prevalence 5.8% Oral fluid test taken but results given according to EIA blood test Phase 1 n=1001 OraQuick ADVANCE EIA Beware of Faint Positives and Seroconverters! Reactive Visit 1 Visit 2 (8-19 days) Case OraQuick ADVANCE N Garrett, J Zelin et al. Oral Fluid HIV testing Beware of Faint Positives and Seroconverters! BASHH/ ASTDA, New York City, May 2008 EIA OraQuick ADVANCE EIA 20m 40m 1 - equivocal - Faint Faint+ Faint Faint+ Faint+ +

5 Results Phase 2 HIV Prevalence 4.8% Results of oral fluid test given followed by confirmatory EIA Phase 2 n=526 OraQuick ADVANCE EIA Results Roll out HIV Prevalence 3.4% Only positive oral fluid test results are followed by confirmatory EIA Roll out n=1337 OraQuick ADVANCE EIA n/a n/a

6 Overall test performance Phase Prevalence Sensitivity Specificity PPV NPV Roll out 3.4 n/a n/a 97.9 n/a Overall Comparison with other HIV POCTs POCT Sensitivity Specificity ADVANCE Our Experience OraQuick OraSure data Determine Insti Determine Combo

7 Patient acceptability n=432 90% 85% 40% Easy & Comfortable Prefer same day result Zelin J, Saunders J et al. OraQuick ADVANCE Rapid HIV-1/2 Test is acceptable to patients and staff. Qualitative findings of a point of care test evaluation study in London, UK. BASHH/ ASTDA, New York City, May 2008 Would have tested sooner Mouth swab and quick! n=46 87% 69% 33% Prefer oral test to finger prick Prefer 20m oral to 10m finger prick Prefer 20m oral to 2m finger prick

8 Conclusions OraQuick ADVANCE had a high specificity, PPV and NPV in our high-risk population Sensitivity improved to 100% after retraining High acceptability and satisfaction scores among patients, with potential importance for reaching patients with undiagnosed HIV The role still has to be defined within the 4 th generation POCT era and low prevalence populations Updated OraQuick version is currently in development Acknowledgements North East London HIV & Sexual Health Clinical Network Jill Zelin, John Saunders, Karen Moir, Merle Symonds, Claudia Estcourt Jane Anderson, Peter Horne Heather Noble, Tom McManus, Health Advising Team

9 Thank you for listening! Additional slides

10 Comparison of OraQuick Oral Fluid HIV 1/2 Specificity in 2008 and Total Tests 187,138 Total Tests 237,676 Total No. of OraQuick Negative 185,554 Total No. of OraQuick Negative 234,742 Total No. of Confirmed Positives 1,414 Total No. of Confirmed Positives 2,264 Total No. of WB Indeterminate 51 Total No. of WB Indeterminate 84 Total No. of OraQuick False Positive 119 Total No. of OraQuick False Positive 586 OraQuick Specificity OraQuick Specificity % CIs % 95% CIs % OraQuick ADVANCE Clinical Features Operating Principle Anti-Human Antibody HIV Antigen Colloidal Gold Conjugated to Protein A Human Antibodies HIV-1/2 Antibodies Control Line Test Line Conjugate pad with colloidal gold particle bound to protein A. Cellulose Membrane Flat Pad Using a lateral flow process, a sample specimen is wicked up by the flat pad of the device and transferred to the cellulose membrane. Human antibodies and HIV antibodies (if present) bind to the colloidal gold particles.

11 OraQuick ADVANCE Clinical Features Operating Principle Anti-Human Antibody HIV Antigen Control C Line Colloidal Gold Conjugated to Protein A Test T Line Human Antibodies HIV-1/2 Antibodies Absorbent Pad Colloidal gold particles containing HIV antibodies bind to the HIV antigen T line forming a visible red band. Colloidal gold particles containing Human antibodies bind to the Anti- Human Antibodies C line forming a visible red band. Any remaining colloidal gold particles are captured and retained by the absorbent pad. BASHH Statement on HIV window period 15 March 2010 Patients attending for HIV testing who identify a specific risk occurring more that 4 weeks previously, should not be made to wait 3 months (12 weeks) before HIV testing. They should be offered a 4th generation laboratory HIV test and advised that a negative result at 4 weeks post exposure is very reassuring/highly likely to exclude HIV infection.