660. Virologic Outcomes of Second-Line Combination Antiretroviral Therapy (cART) Among HIV-infected Persons in Care: a Multi-Center Observational Cohort Study
Session: Oral Abstract Session: Treatment, Complications, and Resistance
Friday, October 19, 2012: 9:00 AM
Room: SDCC 23ABC

Background: Because data are limited on 2nd line cART efficacy in clinical practice, we evaluated virologic outcomes of 2nd cART among patients in three HIV clinical cohorts.

Methods:  Johns Hopkins, UNC, and Vanderbilt contributed observational data on HIV patients who received 1st and 2nd cART defined as ≥2 NRTI with a PI, NNRTI, or INSTI. 2nd cART inclusion criteria were: switch of 3rd agent; PI to darunavir/r or tipranavir/r; or NNRTI to etravirine; with or without NRTI switch. Study period was June 1996 through June 2010. Virologic failure (VF): 1) <0.5 log10 c/mL decrease or VL >400 at >24 wk, if VL>400 at 2nd cART start; and 2) VL>400 at ≥8 wk, if VL≤400 at 2nd cART start.

Results: Of the 488 HIV patients (67% black, 32% women, 34% prior AIDS) 48.6% received an NNRTI, 32.8% an unboosted PI and 18.7% a PI/r as 1st cART. 47% switched from NNRTI to PI and 42% PI to NNRTI (most prior to 2004). Median (Interquartile range [IQR]) VL at switch was 9,565 c/mL (12394,108). Switches in those with VL≤400 (38% of total) occurred later on 1st cART than those with VL>400 (670 [280-1535]) v 520 days [205-1158]; p = 0.01). Figure shows that time to 2nd cART VF was shorter if VL>400 at switch (p = 0.001), though 14% with VL < 400 had VF within 6 mo. Regimen sequence did not impact time to VF. A lower CD4 cell count at switch was associated with a greater hazard of VF on 2nd cART and risk of VF decreased with more recent calendar time (aHR 0.40 [0.15-1.00]; 2008-2010 relative to 1996-98).

Conclusion: Virologic failure of 2nd cART was less likely if patients switched with VL<400, though the risk of VF early after switch was similar (Figure). The success of 2nd line therapy improved over time.

Joseph J. Eron, MD1, Timothy Sterling, MD2, Sonia Napravnik, PhD3, Timothy R. Juday, PhD4, Jonathan Uy, MD4 and Richard Moore, MD, MHS5, (1)University of North Carolina, Chapel Hill, NC, (2)Center for Health Services Research, Vanderbilt University, Nashville, TN, (3)University of North Carolina at Chapel Hill, Chapel Hill, NC, (4)Bristol-Myers Squibb, Plainsboro, NJ, (5)Johns Hopkins University School of Medicine, Baltimore, MD

Disclosures:

J. J. Eron, Bristol-Myers Squibb: Grant Investigator, Research grant

T. Sterling, Bristol-Myers Squibb: Grant Investigator, Research grant

S. Napravnik, Bristol-Myers Squibb: Grant Investigator, Research grant

T. R. Juday, Bristol-Myers Squibb: Employee and Shareholder, Salary

J. Uy, Bristol-Myers Squibb: Employee and Shareholder, Salary

R. Moore, Bristol-Myers Squibb: Grant Investigator, Research grant

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