CROI 2015 Program and Abstracts

Abstract Listing

Poster Abstracts

significantly associated with lower HCV-RNA and higher maximum ALT levels ( p <0.001). Out of 185 infections without spontaneous clearance, 161 (87.0%) were treated with interferon-based therapy, among whom 103/161 (64.0%) achieved sustained virological response. Patients were followed-up for a median time of 48 months (IQR: 29-81). Overall, 12 (6.9%) patients were diagnosed with liver cirrhosis after 13.9 months (IQR: 6.4-40.7) and 11 deaths (5.3%) occurred during the observation period. Causes of death were as follows: AIDS (n=2), cardiovascular events (n=4), drug overdose/suicide (n=2), or other (n=3). No liver-related deaths or liver transplants occurred. In multivariable analysis, the number of reinfections increased the risk of developing significant fibrosis (adjusted-HR=2.89; 95%CI=1.90-4.39). Non-response to interferon-based treatment was the only significant determinant for increased risk in liver cirrhosis (HR=5.47; 95%CI=1.46-20.53). Conclusions: Over the past decade, interferon-based treatment of HCV infection has provided sustained virological response for many HIV-positive MSMwith acute HCV infection. However, the fact that severe outcomes were rare suggests that patients may wait for newer regimens with fewer side effects. 672 Hepatitis C in MenWho Have Sex with MenWith New HIV Diagnoses in Los Angeles KaraW. Chew 1 ; Marjan Javanbakht 2 ; Laurel Clare 1 ; Lorelei Bornfleth 1 ; Debika Bhattacharya 1 ; Pamina Gorbach 2 ; Martha L. Blum 3 1 David Geffen School of Medicine at UCLA, Los Angeles, CA, US; 2 UCLA Fielding School of Public Health, Los Angeles, CA, US; 3 Community Hospital of the Monterey Peninsula, Monterey, CA, US Background: Geographic and sociodemographic characterization of hepatitis C virus (HCV) transmission amongst men who have sex with men (MSM) has been limited. Our aim was to characterize HCV prevalence, risk factors for HCV co-infection, and patterns of HIV and HCV co-transmission and transmitted drug resistance mutations (DRMs) in newly HIV-diagnosed Los Angeles MSM. Methods: We extracted viral RNA from stored plasma samples from the MetroMates cohort, a Los Angeles cohort of recently infected (within the past year) or newly diagnosed HIV-infected MSM with well-characterized substance use and sexual behavioral characteristics via ACASI surveys. Samples were screened for HCV by qPCR. HCV E1, E2, core, NS3 protease and NS5B polymerase and HIV-1 protease and reverse transcriptase (RT) regions were amplified and sequenced. Phylogenetic analysis was used to determine relatedness of HCV and HIV-1 isolates within the cohort. Protease and polymerase sequences were examined for DRMs, including the HCV mutations V36M/A, T54A/S, V55A, Q80K, R155K, A156S/T, D168T/V, I/V170A and S282T. Results: Of 185 newly HIV-diagnosed MSM, the majority (65%) were of minority race/ethnicity and recently infected (57.8%). A minority (6.6%) reported injection drug use (IDU), whereas 52.8% reported recent substance use, primarily cannabis or stimulant use. High risk sexual behaviors included 74.6%with unprotected receptive anal intercourse, 32.4% group sex, and 5.7% fisting. One-third reported a history of recent sexually transmitted infection (STI). Only 3 (1.6%) subjects had detectable HCV RNA, two genotype 1a and one 3a. The HCV-positive subjects were slightly older, but not statistically significantly. Only 1 subject with HCV had a history of IDU. There were too few HCV infections to identify significant risk factors for HCV. One subject had an HIV RT mutation (K103N). None had clinically relevant NS3 or NS5B HCV DRMs. Amongst the 3 HCV-infected subjects, HIV and

HCV sequences were unrelated by phylogenetic analysis. Characteristics of the cohort overall and by hepatitis C status

Poster Abstracts

*HIV viral load and CD4 measurements were collected after study enrollment, at which time some participants were on HIV antiretroviral therapy. CD4 cell counts were available for 80 subjects. Conclusions: Prevalence of HCV co-infection was low and there was no evidence of HIV-HCV co-transmission in this cohort of relatively young, predominantly minority, newly HIV-diagnosed MSM, most with early HIV infection, with high rates of high risk sexual behaviors, STI, and non-IDU. The low HCV prevalence in these newly HIV-diagnosed MSM suggests HIV precedes HCV acquisition, and not the reverse, and presents an opportunity for targeted HCV prevention campaigns in this high-risk population.

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CROI 2015