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Medical Advisory Board


The Board of Trustees and staff are supported by a medical advisory board (MAB), which offers expert advice in the fields if HIV and nutrition.

Two Trustees sit on the MAB, Matt Wills and Dr Rachel Coyle. The Advisory members of the MAB are

Alastair Duncan (Chair) -  Principal Dietitan, HIV Care & AIDS, Guy's and St Thomas' Hospital, London

Alastair works as a dietitian at Guy’s and St. Thomas’ Hospital in London, and as a Lecturer in Diabetes and Nutrition at King's College London.  His first degree in Microbiology led onto researching HIV malabsorption, highly prevalent before the advent of combination antiretroviral therapy. Alastair has specialised in HIV Dietetics for the last 19 years. He has volunteered with The Food Chain for 25 years, and was elected Chair of the Board of Trustees from 2000-2003. As part of The Children’s HIV Association Alastair visits South Africa to help facilitate the roll-out of antiretrovirals to infants and children, and also travelled to Botswana and Lesotho as Winston Churchill Fellow of 2007. His research interests include the metabolic impact of both HIV and antiretroviral therapy, and was awarded a PhD in 2016 as part of an NIHR Clinical Research Fellowship. He is currently Chair of the Dietitians in HIV Care group.


Dr Stuart Gibson- Clinical Psychologist, CASCAID

Dr Stuart Gibson works as a clinical psychologist in a multidisciplinary mental health service for people living with HIV in south London. For more than 12 years he has practiced clinical psychology, lectured, trained, and conducted research on the psychological aspects of living with HIV in the United Kingdom, Canada and the United States. Stuart also has many years of experience in training about sexual diversity in psychology and psychiatry. He is the current Chair of the Faculty for HIV & Sexual Health in the British Psychological Society and has honorary appointments with the Institute of Psychiatry at King's College London and Salomons (Canterbury Christ Church University).

Ranjababu Kulasegaram,  FRCP ( UK )

Ranjababu Kulasegaram - consultant physician and training programme director for HIV/Genito-Urinary Medicine at Guy’s and St.Thomas’ NHS Foundation Trust, leads the HIV Treatment Advice Clinic with special interests in HIV/Hepatitis, HIV/Brain, Haemophilia/HIV infection and HIV in-patient management.

Vice Chair of the BHIVA Hepatitis Working Group

Dip HIV examiner

British HIV Association (BHIVA) executive committee member, the Educational and Scientific Committee and E-Learning Working Group.


Jason Warriner  RN, BSc, PGDip, Cmgr

Jason has worked for Terrence Higgins Trust since August 2009 as Clinical Director/Service Quality & Governance Director. Prior to working for THT, Jason has held a number of senior nursing positions in the NHS. He has worked in the field of HIV and sexual health for a number of years in the UK and also has experience of working on a HIV project in South Africa. Jason served as Chair of the Royal College of Nursing Congress from 2006 to 2010. He is currently the sexual health and HIV representative on the RCN’s public health forum and volunteers as the Healthcare Services Manager for the charity Crisis UK, the national charity for single homeless people.