The pending introduction of a new formulation of tenofovir, a prodrug of the original formulation, raises the question of equivalence in terms of outcomes and virological suppression and adverse effects.  Don Smith and Mark Bloch presented data clearly showing that the newer formulation of tenofovir - tenofovir alafenamide (TAF) is superior to the original tenofovir disoproxil fumarate (TDF).  TDF, while a very effective agent, may cause clinical renal toxicity and adversely affect bone marrow density.  TAF is a novel prodrug that has a 90% reduction in serum plasma tenofovir levels and hence has the potential to reduce the adverse effects seen with TDF.

The speakers presented results of the GS-292-0109 study which looked at tenofovir disoproxil fumarate (TDF) 300mg switch to tenofovir alafenamide (TAF) 10mg in a cohort of well controlled patients at 48 weeks on once daily optimised background therapy.  1196 patients were randomised 2:1 to receive TAF based therapy to TDF based therapy with virological success occurring at least equally across both groups indicating non- inferiority.  Further positive results were seen in the TAF group where Statistically significant increases in BMD and multiple tests of renal function compared to those patients on theor prior TDF based regimen.  Lipid profiles however favoured TDF based regimens.  These results support the preferential use of TAF, especially in those at risk of metabolic and/or renal adverse effects.......well when it becomes available!

The afternoon session: O21 - HIV and co-morbidity started with two speakers who complemented each others presentations very well.  

Dr Paddy Mallon provided an excellent overview of the cardiovascular risk factors associated not only with HIV itself, but the ART used in its management - especially abacavir.

Importantly he provided an overview on the potential role of increased platelet activity and their role in increasing the risk of vascular events and thrombosis. He concluded with reference to a current trial of pitavastatin to assess its potential in reducing hyperlypidaemic risk.  

Dr Janine Trevillyan followed on with an excellent overview of why HIV patients are at increased risk of CVD including dyslipidaemias, immune activation, platelet activity and other risk factors such as a higher incidence of smoking and diabetes.  

Janine then provided an overview of her current research activities on platelet derived soluble glycoprotein VI (sGPVI), where she described the observation that sGPVI levels are reduced in the month preceding a cardiac event in HIV positive patients and may have an important role in promoting cardiovascular disease in this population.  It was postulated that this reduction in levels may be linked to a pathological process leading to MI, or sign of an unstable plaque.

Challenging start to the day with two interesting trainee case presentations with Sian Goddard presenting two linked cases of syphilis in a mother and daughter and a reminder to screen at risk immigrants; and Vinita Rane presenting a case of HSV penile ulceration in a HIV positive patient, with other confounding STIs, that was successfully treated with imiquimod. 

Congratulations to both on these excellent presentations.