CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

Figure. Distribution of Factor 1 scores across categories of GFR and urine protein:creatinine ratio outcomes. Conclusions: Higher circulating levels of immune activation markers among treated HIV+ individuals, despite virologic suppression, may partially explain their higher burden of kidney dysfunction compared to HIV- persons.

THURSDAY, FEBRUARY 26, 2015 Session P-Q9 Poster Session

Poster Hall

2:30 pm– 4:00 pm Renal Transplantation: Long-Term Outcomes 798 Risk Factors for Acute Allograft Rejection in HIV Positive Kidney Transplant Recipients Esther N. Gathogo 1 ; Mark Harber 2 ; Sanjay R. Bhagani 2 ; Joanne Baxter 3 ;Vincent Lee 4 ; Jeremy Levy 5 ; Rachael Jones 6 ; Rachel Hilton 7 ; Graham Davies 1 ; Frank A. Post 1

1 King’s College London, London, United Kingdom; 2 Royal Free London NHS Foundation Trust, London, United Kingdom; 3 North Manchester General Hospital, Manchester, United Kingdom; 4 Central Manchester University Hospitals, Manchester, United Kingdom; 5 Imperial College Healthcare NHS Trust, London, United Kingdom; 6 Chelsea and Westminster Hospital, NHS Foundation Trust, London, United Kingdom; 7 Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom Background: Kidney transplantation (KT) of HIV positive patients has transformed the management of end-stage kidney disease in this population. Although favourable outcomes have been reported, patients experience high rates of acute allograft rejection (AR). We examined factors associated with AR in the first year post-KT, with particular emphasis on the choice of calcineurin inhibitor (CNI) immunosuppressive therapy. Methods: We conducted a national observational cohort study of HIV/KT in the UK. Patients were included if HIV positive at KT, transplanted in the UK between 01/2005 and 12/2013, and did not experience primary graft failure. Kaplan-Meier methods were used to estimate host/graft survival and cumulative incidence of biopsy proven AR. Logrank tests were used to compare survival, and Cox proportional hazard models to examine factors associated with AR. Results: Seventy-seven (91%) of 85 HIV+ kidney transplant recipients were included in the analyses. The mean age was 44.8 years, 75% black ethnicity, median CD4 cell count 277 cells/mm 3 , 97% had HIV RNA <200 c/mL. 32 participants initiated ciclosporin (CsA) and 45 Tacrolimus (Tac) based immunosuppression. The overall one-year patient and graft survival were 97.3% and 94.6% respectively. AR was observed in 28 patients (36%), with a median time from KT to AR of 2.6 (IQR 0.5, 5.9) months. The cumulative incidence of AR at 1 year was 57% and 20% among patients who started CsA and Tac respectively (p=0.002). The only factor that was significantly associated with AR was choice of CNI (HR for Tac vs, CsA 0.30 [95% CI 0.13, 0.67], p=0.003). Recipient age, gender, ethnicity, deceased donor graft, year of KT, nadir or current CD4 cell count and viral hepatitis status were not associated with AR. In a sensitivity analysis which excluded 8 patients with AR in the first two weeks post KT, use of Tac (HR 0.17 [0.06, 0.48]), abacavir (0.40 [0.17, 0.96]) and protease inhibitors (2.56 [1.04, 6.27]) were associated with AR in univariable analysis; only use of Tac (HR 0.26 [0.07, 0.94]) associated with AR in multivariable analysis. Use of Tac was generally safe with one patient each developing CNI toxicity with CsA and Tac. Conclusions: The use of Tac was associated with a significantly reduced incidence of AR in the first year post KT. Our data suggest that Tac is the preferred CNI in the context of HIV infection. Use of protease inhibitor-sparing antiretroviral therapy may facilitate the safe administration of Tac. 799 Survival in HIV-Positive Transplant Recipients Compared to Matched Registry Controls Michelle E. Roland 1 ; Burc Barin 2 ; Shirish Huprikar 3 ; Michael Wong 4 ; Emily Blumberg 5 ; David Simon 6 ; Margaret Ragni 7 ; Don Stablein 2 ; Peter Stock 1 HIV-TR StudyTeam 1 University of California San Francisco, San Francisco, CA, US; 2 EMMES Corporation, Rockville, MD, US; 3 Mount Sinai School of Medicine, New York, NY, US; 4 Beth Israel Deaconess Medical Center, Boston, MA, US; 5 University of Pennsylvania, Philadephia, PA, US; 6 Rush University Medical Center, Chicago, IL, US; 7 University of Pittsburgh, Pittsburgh, PA, US Background: We designed a 21-center study to test the hypothesis that immunosuppression does not accelerate HIV disease progression in transplant recipients with relatively intact immune systems and suppressed viremia. We further hypothesized that HIV+ patients would be higher risk but acceptable transplant candidates, similar to other higher risk groups. We previously described 3-year outcomes in 150 kidney (KTR) and 125 liver recipients (LTR). We now describe 5-year outcomes compared with HIV-negative controls. Methods: We examined time to graft failure, death-censored graft failure, and death. Controls were identified from Scientific Registry of Transplant Recipients (SRTR). We fit 4 proportional hazards (PH) regression models: risk-matched and demographic-matched models examining HIV status, a demographic-matched model adjusting for risk score, and an unmatched model. We calculated case risk scores from a PH model adjusting for predictors among SRTR controls, identifying 4 controls per case after ranking by risk score. We created demographic-matched sets from randomly selected controls matched for age, gender, race, donor type, and time of transplant. Results: In KTR, risk-matched and unmatched analyses indicated a marginally significant hazard ratio (HR) for graft loss (HR 1.4 [p=0.052] and 1.3 [p=0.07]), but no significant increase in risk of other events among HIV-positive KTR. All models demonstrated a statistically significantly higher relative hazard of graft loss or death (except risk-matched and

Poster Abstracts

486

CROI 2015