Correlation of HIV tropism with immunological response under HAART - PowerPoint PPT Presentation

Correlation of HIV tropism with immunological response under HAART Joëlle Bader Thomas Klimkait May 4 th 2012 Department Biomedicine University of Basel

Viral load vs. CD4 recovery under HAART 500 CD4 cells/mL Kaufmann et al; AIDS 2008,41:361-372

X4 tropism at baseline correlates with more rapid progression [Weiser et al; AIDS 2008,22:469-479] Does X4 lead to poor CD4 recovery or does a low response cause X4?

Viral load vs. CD4 recovery under HAART 500 CD4 cells/mL Kaufmann et al; AIDS 2008,41:361-372

Study characteristics • n = 67 patients • Under HAART for >3 years, (no maraviroc involved) • All show full viral response < 20 c/mL • CD4 cells > 500 /mL after 3-5 years = no plateau n = 35 patients • CD4 cells < 500 /mL after 3-5 years = plateau n = 32 patients • Tropism determination (XTrack) around time of HAART initiation

XTrack system

Results Tropism in the study population analyzed by XTrack 69 % 21 % 10 %

Results Tropism in the study population by XTrack / G2P 76 % 69 % 21 % 24 % 21 % 10 %

Results Tropism in the study population by XTrack / G2P 76 % 58 % 30 % 24 % 12 % 67 patients  11 cases (16%) discordance between XTrack/G2P 3/4 phenotypes agree with XTrack

Results Continuous response vs. plateau 62 % 39 % 75 % 25 %

Results Continuous response vs. plateau 62 % 39 % 75 % 71 % 57 % 43 % 50 % 50 % 25 % 29 %

Results Comparison of different FPR cutoff’s

Conclusion and outlook • Early X4 use predicts poor CD4 recovery • Tropism test older than 3 years is predictive (despite viral response) • XTrack is superior for mixed populations ? Does drug pressure play a role (PI vs. NNRTI)? ? Which role do viral minorities play? ? Is there clinical utility of our data for the use of MVC? ? Does G2P classify too many R5 viruses as X4-tropic?