HIV Testing: What s New, What s Next August 25, 2016

Transcription

1 HIV Testing: What s New? What s Next? Bernard M. Branson, MD Principal Consultant Scientific Affairs, LLC Atlanta, Georgia Washington, DC: August 25, 2016 Learning Objectives After attending this presentation, participants will be able to: Compare the relative merits of different US Food and Drug Administration (FDA) approved HIV tests for different circumstances Describe how new HIV tests fit in with current HIV testing recommendations Recognize the increasing role that HIV RNA tests play in HIV diagnosis Slide 3 of 49 Outline The basics New tests: rapid, lab, & supplemental How differences between tests relate to accuracy On the horizon Slide 5 of 49 Bernard M. Branson M.D. 1

2 HIV Infection and Laboratory Markers HIV RNA (plasma) HIV p24 Ag HIV Antibody IgM IgG Days Infection Lab Lab Ag/Ab Ab tests tests Most Rapid tests Modified after Busch et al. Am J Med Slide 6 of 49 HIV-1 antigens and RNA gp120 gp 41 p24 RNA Slide 7 of 49 CLIA-waived rapid HIV-antibody tests Oraquick Advance DPP HIV 1/2 Chembio Sure Check INSTI HIV 1/2 Chembio Stat Pak Uni-Gold Recombigen Slide 8 of 49 Bernard M. Branson M.D. 2

3 Which antibodies do rapid tests detect? 1. p24 antibody 2. gp41 antibody 3. gp120 antibody 4. gp41 and gp120 antibody 5. All three: p24, gp41, and gp120 Slide 9 of 49 gp41 gp41, 120 gp41, 120 Oraquick Advance DPP HIV 1/2 Chembio Sure Check gp41 INSTI HIV 1/2 gp41, 120 Chembio Stat Pak gp41, 120 Uni-Gold Recombigen Slide 10 of 49 How large a specimen? 5 µl Oraquick Advance 10 µl 3 µl DPP HIV 1/2 Chembio Sure Check 50 µl 5 µl 50 µl INSTI HIV 1/2 Chembio Stat Pak Uni-Gold Recombigen Slide 11 of 49 Bernard M. Branson M.D. 3

4 Chembio SureCheck DPP HIV 1/2 What s new? INSTI HIV 1/2 Slide 12 of 49 Product name change: Clearview Complete is now Sure Check Slide 13 of 49 DPP HIV-1/2 Finger-stick, oral fluid Swab gums 4 times (15 seconds) or 10 µl whole blood Read time min blood 40 min oral fluid Slide 14 of 49 Bernard M. Branson M.D. 4

5 Dual Path Platform Technology Strip 2 Conjugate Strip 1 Specimen Slide 15 of 49 INSTI HIV-1/2 CLIA-waived for whole blood, finger-stick 50 µl specimen volume Results <1minute Detects IgM antibodies Moshgabadi et al, J Clin Virol 2015 What s new in the lab? Slide 17 of 49 Bernard M. Branson M.D. 5

6 Bio-Rad Ag/Ab Combo 2011 Abbott Architect Ag/Ab Combo th Generation Ag/Ab Combo Siemens Advia Centaur CHIV 2015 Slide 18 of 49 Chemiluminescence Immunoassays Magnetic Micro-Particles Coated with Antigens and antibody Patient Sample LITE Reagent Antigens and antibodies labeled with AE AE Αnti- p24 Monoclonal IgM/IgG p24 Ag WASH AE AE AE AE 2 Αnti- p24 Monoclonals WASH Trigger Solution Chemiluminesce Relative light units Slide 19 of 49 Random Access Multiplatform analyzers for HIV testing On-board Refrigeration of Multiple Different Assays Slide 20 of 49 Bernard M. Branson M.D. 6

7 Random Access Multiplatform analyzers for HIV testing STAT sample requests without pausing Results in <60 minutes Slide 21 of 49 Abbott Architect Ag/Ab Combo 2010 p24 Antigen Control Siemens Advia Centaur CHIV Antibody 2015 gp41, gp120 Determine Combo Ag/Ab Rapid Test th Generation - CLIA-waived - Whole blood (50µL) Slide 22 of 49 Which factor is least important for the accuracy of a rapid HIV antibody test? 1. The type of specimen (serum, whole blood, oral fluid). 2. The volume of specimen the test requires. 3. The way the test is designed. 4. The time it takes to run the test. 5. The prevalence of HIV in the population tested. Slide 23 of 49 Bernard M. Branson M.D. 7

8 Cumulative frequency of positive tests HIV Testing: What s New, What s Next August 25, 2016 Accuracy: Performance Characteristics Sensitivity The ability of the test to identify correctly those who have the disease We Are Spoiled. HIV: 99.8% Specificity The ability of the test to identify correctly those who do not have the disease HIV: 99.8% Slide 24 of 49 HIV RNA (plasma) HIV p24 Ag HIV Ab HIV Infection Days Eclipse Period Viral Detection Acute Infection IgM Antibody Detection Recent Infection IgG Antibody Detection Positive Western Blot Longstanding Infection Seroconversion window Slide 26 of 49 Relative Sensitivity during Seroconversion (plasma) % Cumulative Frequency days before positive Western blot 26 seroconverters were analyzed with 14 tests 17 seroconverters with Positive WB used for cumulative frequency analysis Genprobe Architect 4th BioRad 4th Advia 3rd Vitros 3rd Abbott 3rd BioRad 3rd Insti Multispot Reveal Statpak Complete Unigold Oraq Adv Slide 27 of 49 Bernard M. Branson M.D. 8

9 APTIMA (-26) Architect Ag/Ab Combo (-20) Bio-Rad Ag/Ab Combo (-19) Advia Centaur Ag/Ab (-18) Determine Ag/Ab Combo (-15) Advia Centaur (-14) Ortho Vitros (-13) GS 1/2+O (-12) INSTI (-9) Multi-Spot (-7) Reveal G3, DPP (-6) SureCheck HIV-1/2 (-5) HIV-1/2 STAT-PAK (-5) Multispot Unigold (-2) Supplemental (-1) Geenius OraQuick Supplemental (-1) (-1) WB positive Vironostka (+2) Oral Fluid (Avioq EIA) HIV Testing: What s New, What s Next August 25, 2016 Sequence of Test Positivity Relative to WB (plasma) 166 specimens, 17 Seroconverters - 50 % Positive Cumulative Frequency Bangkok Tenofovir Study: Delayed HIV detection by oral fluid in patients on PReP Participants receiving tenofovir (who became HIV-infected) took longer to develop a reactive OraQuick (191.8 days) than participants receiving placebo (16.8 days) Determine Combo whole blood (-8) - Suntharasamai et al, PLoS One 2016 Days before WB positive (50% Cumulative Frequency) Modified from Owen et al, J Clin Micro 2008, Masciotra et al, J Clin Virol 2011, 2013, and 2016 CDC Diagnostics Conference +40 Luo et al, J Clin Virol 2013 Slide 28 of 49 Determine Combo Ag/Ab with Whole Blood In 6 studies involving >26,000 persons, Determine Combo failed to detect p24 antigen in whole blood from any of the 26 acute infections. CDC study: Eight seroconverters showed a median delay of 6 days between DC reactivity with plasma and reactivity with whole blood CDC HIV Diagnostics Conference: Slide 29 of 49 Quick Case Study 25 year old MSM in an HIV-discordant relationship, on PrEP since 12/2015. Perfect adherence by history. Also had 2 other sex partners. 4th generation testing repeatedly negative until May 2016: Positive 4 th gen, negative Multispot, HIV RNA<20, signal detected Repeat 2 and 4 weeks later: same results. Slide 30 of 49 Bernard M. Branson M.D. 9

10 Western blot Patient s WB: bands at gp160 and p55, weak bands at p31, and p study: false-negative Oraquick and waning or absent gp41 titers in patients on early, effective therapy Bangkok tenofovir study Genotype: Multiple drug resistance mutations (including TDF/FTC), virus not related to that of his virally suppressed partner. - O Connell et al, J Clin Micro 2003 Slide 32 of 49 HIV-1/HIV-2 Differentiation Assays FDA approved, March 2013 Serum Control HIV-1 Recombinant gp41 HIV-2 Peptide gp36 HIV-1 Peptide gp41 Multispot HIV-1/HIV-2 Slide 33 of 49 HIV-1/HIV-2 Differentiation Assays FDA approved, March 2013 Serum Control HIV-1 Recombinant gp41 FDA approved, Oct HIV-2 Peptide gp36 HIV-1 Peptide gp41 Multispot HIV-1/HIV-2 Geenius HIV-1/HIV-2 Slide 34 of 49 Bernard M. Branson M.D. 10

11 Geenius TM HIV-1/2 Lines HIV-1 & HIV-2 Associated Lines Slide 35 of 49 Dual Path Platform: Add 5 µl serum/plasma Or 15 µl whole blood to specimen well Add 5 drops buffer To buffer well. Bernard M. Branson M.D. 11

12 Insert test cassette in reader for automated interpretation Geenius Results: New Interpretations Slide 40 of 49 Bernard M. Branson M.D. 12

13 On the Horizon 4 th generation HIV-1/2 immunoassay (+) (-) Negative for HIV-1 and HIV-2 antibodies and p24 Ag HIV-1/HIV-2 antibody differentiation immunoassay HIV-1 (+) HIV-2 (-) HIV-1 antibodies detected June 27, 2014 HIV-1 (-) HIV-2 (+) HIV-2 antibodies detected HIV-1 (+) HIV-2 (+) HIV antibodies detected HIV-1 (-) or indeterminate HIV-2 (-) HIV-1 RNA viral load RNA (+) RNA (-) Acute HIV-1 infection Negative for HIV-1 Slide 42 of 49 How about 4 th generation HIV-1/2 immunoassay (+) HIV-1 RNA viral load (-) Negative for HIV-1 and HIV-2 antibodies and p24 Ag VL detectable HIV-1 infection Useful clinical information VL (-) HIV-1+ (Viral suppression) HIV-1/HIV-2 antibody differentiation assay HIV-2+ HIV-2 infection Negative Slide 43 of 49 Bernard M. Branson M.D. 13

14 Point-of-Care Nucleic Acid Tests Xpert HIV-1 viral load 1 ml plasma Results in 90 minutes LOD 32 copies/ml CE-marked December 2014 GeneXpert Not available in U.S. Slide 44 of 49 Point-of-Care Nucleic Acid Tests Xpert HCV viral load 1 ml serum or plasma Genotypes 1-6 Range ,000,000 IU/mL Results in 105 minutes CE-marked April 2015 Not available in U.S. Slide 45 of 49 Point-of-Care Nucleic Acid Tests 25 µl whole blood specimen Alere q HIV-1/2 Detect HIV-1 or HIV-2 viral load in 60 minutes CE-marked March 2015 Not available in U.S. Slide 46 of 49 Bernard M. Branson M.D. 14

15 Point-of-Care Nucleic Acid Tests Lab in a Tube Influenza A/B FDA cleared Strep A FDA cleared Results in 15 minutes CLIA-waived May 2015 Cobas LIAT PCR HIV under development Slide 47 of 49 Summary HIV screening tests keep getting better HIV RNA viral load will play an increasingly important role in diagnosis You never know what s next Slide 48 of 49 Bernard M. Branson M.D. 15

16 Suggested Readings 2016 HIV Diagnostics Conference. Accessed on August 11, Branson BM. HIV testing updates and challenges: when regulatory caution and public health imperatives collide. Curr HIV/AIDS Rep. 2015;12(1): Centers for Disease Control and Prevention and Association of Public Health Laboratories. Laboratory testing for the diagnosis of HIV infection: updated recommendations. Accessed on February 2, Masciotra S, Price KA, Sprinkle P, Wesolowski L, Owen SM. Performance evaluation of the CHEMBIO DPP(R) (dual path platform) HIV-1/2 assay in early and established infections. J Clin Virol. 2015;70: