Predictors of a poor immune response to highly active antiretroviral therapy in patients with a sustained virologic response: The Australian HIV Observational Database Kathleen Glenday 1, Kathy Petoumenos 1, John Chuah 2, Anne Mijch 3, Brian Mulhall 4, Mark Kelly 5 and David A Cooper 1,6 on behalf of the Australian HIV Observational Database 1 National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Sydney, Australia 2 Gold Coast Sexual Health Clinic, Gold Coast, Australia 3 The Alfred Hospital, Melbourne, Australia 4 University of Sydney, Sydney, Australia 5 AIDS Medical Unit, Brisbane, Australia 6 St Vincent’s Hospital, Sydney, Australia

Predictors of a poor immune response (<200 cells/µL) to HAART in patients with sustained virological suppression *significant in univariate analysis only. OR adjusted for mode of HIV-infection, prior AIDS, prior HCV infection, baseline HIV RNA and CD4. †CD4+ T-cell nadir prior to commencing the inclusion regimen Other covariates tested for inclusion in the model that were non-significant include prior ART, NNRTI- vs. PI-based regimens, AZT vs. d4T containing regimens, year started regimen, year of HIV infection, first/second HAART regimen, age, sex, increasing vs. decreasing CD4 count prior to start of HAART, HBV.

Key Findings Predictors of a poor immune response (<200 cells/µL): Immune status prior to commencing ART HCV co-infection Mode of infection other than MSM (with or without IDU) Prior ART & type of ART regimen NOT significantly associated with poor immune response outcome No significant difference by immune response group in time to AIDS or death in this analysis

The Australian HIV Observational Database Acknowledgements D Ellis, General Medical Practice, Coffs Harbour, NSW; J Chuah*, D Lester, W Fankhauser, B Dickson, Gold Coast Sexual Health Clinic, Miami, QLD; M Bloch, T Franic, S Agrawal, Holdsworth House General Practice, Darlinghurst, NSW; J Anderson, P Cortissos, The Carlton Clinic, Carlton, VIC; S Mallal, C Forsdyke, S Bulgannawar, Department of Clinical Immunology, Royal Perth Hospital, Perth, WA; NJ Roth*, J Nicholson, Prahran Market Clinic, South Yarra, VIC; D Allen, Holden Street Clinic, Gosford, NSW; D Smith, C Mincham, Lismore Sexual Health & AIDS Services, Lismore, NSW; D Baker*, R Vale, 407 Doctors, Surry Hills, NSW; D Russell, J Leamy, C Remington, Cairns Sexual Health Service, Cairns, QLD; C O’Connor; Royal Prince Alfred Hospital Sexual Health, Camperdown, NSW; D Sowden, A Walker*, Clinic 87, Sunshine Coast & Cooloola HIV Sexual Health Service, Nambour, QLD; D Orth; D Youds, Gladstone Road Medical Centre, Highgate Hill, QLD; E Jackson, D Hunter, K McCallum, Blue Mountains Sexual Health and HIV Clinic, Katoomba, NSW; T Read, J Silvers, Melbourne Sexual Health Centre, Melbourne, VIC; A Kulatunga, P Knibbs, Communicable Disease Centre, Royal Darwin Hospital, Darwin, NT; A Mijch, J Hoy, K Watson*, M Bryant, The Alfred Hospital, Melbourne, VIC; M Gotowski, S Taylor, L Stuart-Hill, Bligh Street Clinic, Tamworth, NSW; D Cooper, A Carr, M Lacey, K Hesse, St Vincent’s Hospital, Darlinghurst, NSW; R Finlayson, I Prone, Taylor Square Private Clinic, Darlinghurst, NSW; MT Liang, Nepean Sexual Health and HIV Clinic, Penrith, NSW; M Kelly, P Negus, H Magon, AIDS Medical Unit, Brisbane, QLD; K Brown, N Skobalj, Illawarra Sexual Health Clinic, Warrawong, NSW; L Wray, H Lu, Sydney Sexual Health Centre, Sydney, NSW; W Donohue, A Lohmeyer, The Care and Prevention Programme, Adelaide University, Adelaide, SA; I Woolley, Monash Medical Centre, Clayton, VIC; Dubbo Sexual Health Centre, Dubbo, NSW; P Canavan*, National Association of People living with HIV/AIDS; C Lawrence*, National Aboriginal Community Controlled Health Organisation; I Zablotska*, National Centre in HIV Social Research, University of NSW, Sydney; B Mulhall*, Department of Public Health and Community Medicine, University of Sydney, Sydney, NSW; M Law*, K Petoumenos*, K Glenday*, National Centre in HIV Epidemiology and Clinical Research, University of NSW, Sydney; NSW. *Steering Committee member , † Current Steering Committee chair The Australian HIV Observational Database is funded as part of the Asia Pacific HIV Observational Database, a program of The Foundation for AIDS Research, amfAR, and is supported in part by a grant from the U.S. National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID) (Grant No. U01-AI069907). The National Centre in HIV Epidemiology and Clinical Research is funded by The Australian Government Department of Health and Ageing, and is affiliated with the Faculty of Medicine, The University of New South Wales.