The first day of the HIV Drug Therapy conference in Glasgow today featured presentations and panel discussions of a number of complex clinical cases focussing on antiretroviral treatment choices in the context of other comorbidities, particularly Hepatitis C infection.
Dr Alessia Dalla Pria from Chelsea and Westminster Hospital presented the case of a male patient with HIV-associated B cell lymphoma infiltrating the liver, complicated by HCV-related cirrhosis and acute renal insufficiency. The timing of treatment of both the lymphoma and Hepatitis C infection was discussed, with the two conditions in this case being treated concurrently. The take-home messages: it is important to consider not only CYP3A4 drug-drug interactions, but also P-glycoprotein P and other trans-membrane transporters in considering DDIs, as the concentration of R-CHOP chemotherapy can be increased by Hep C treatment leading to increased toxicity. Interferon and Ribavirin are also contraindicated during cancer treatment due to overlap toxicity with chemotherapy and the unknown effects of interferon on lymphoproliferative disorders. Protease inhibitors shouldn't be used in patients with Child-Pugh B or C decompensated cirrhosis.
The differences in rates of diagnosis of HIV, linkage to care, retention in care, appropriate ARV treatment and successful viral suppression (the HIV care cascade) in Italy, the USA and the UK were highlighted by Dr Cristina Mussini from the University of Modena. The rates in the USA were surprisingly poor relative to those of Italy and the UK, with a large percentage of HIV positive people being lost to follow-up, emphasising the importance of universal health care in improving accessibility of HIV treatment and management of the HIV epidemic.
In a study of the HIV care cascade among 12 infectious diseases clinics in Italy in 2013, approximately 7-9% of patients were lost in each successive column of the care cascade, prompting discussion on how retention in care can be optimised - in particular, clinic protocols for systematically monitoring retention rates and contacting patients who don’t attend planned reviews. A study done at Chelsea and Westminster Hospital in 2011 showed that of patients presenting late with opportunistic infections, 62% had had a positive HIV test previously but had failed to be retained in care.
Dr Laura Waters reported on a study conducted in the USA using point-of-care HIV tests administered in pharmacies in the community. Of 1000 tests done, 1.5% had a positive result, at an overall cost per positive test (new diagnosis of HIV) of around $30. This may be a potentially cost-effective approach to improving access to HIV testing if high-risk groups are targeted.
Linda-Gail Bekker from the Desmond Tutu HIV Centre in Cape Town talked about a study currently underway of the use of PrEP in 300 female sex workers in South Africa. She reported that between 45 and 70% of female sex workers in the region are HIV positive, making this a particularly vulnerable group. Elsewhere it was reported that non-oral forms of PrEP (such as injection, implant or ring, if available) would be preferred by 55% of African women due in part to the stigma associated with taking anti-retroviral medication.