Day 2 Durban: HCV and PrEP

Of the plenary session today what really stood out was Anton Pozniaks session ‘TB and Co-infections: the long game.  During the session he reminded us that TB is now the leading cause of death for people living with HIV.  He detailed steps to disease elimination for TB, hepatitis B and C – a very long game indeed.

In ‘The Living with HIV: Long-Term Effects’ Amanda Mocroft (PDB0101) examined renal function in patients in the START study.  eGFR was significantly lower in the deferred arm versus the immediate treatment arm. This finding reached significance in the non-adjusted analysis despite the use of potentially nephrotoxic drugs such as tenofovir.  Yet another reason to start ART early.

PrEP has been a major theme at this conference.  More good news was provided by Jean-Michel Molinain the extension arm of the Ipergay study  (WEAC0102).   This study used intermittent PrEP and previously reported the high efficacy of PrEP with TDF/FTC taken ‘on demand’ in high risk MSM – an 86% relative reduction in HIV-incidence in the TDF/FTC arm vs Placebo (95% CI: 40-98, P=0.002).  All participants were offered open-label TDF/FTC.  During 515 person-years only 1 HIV infection occurred giving a risk of HIV of 0.19 (0.01-1.08) per 100 per year.  This patient reported that he had ceased PrEP.

 Also continuing good news for HIV/HCV co-infection.  In the ‘Bad Bugs’ session Norbert Bräu  (WEAB0301) presented the results of the ASTRAL-5 study Sofosbuvir/velpatasvir was given for 12 weeks to 106 patients.  The genotype distribution was 62% GT1a, 11% GT1b, 10% GT2, 11% GT3, and 5% GT4. No patient experienced confirmed HIV virologic rebound (HIV-1 RNA ≥400 copies/mL).  SVR rates were 95% overall, and 100% with cirrhosis and 97% the previously treated.

As this combination will be widely used in Australia the next session was very relevant. AnnieLuetkemeyer (WEAB0302)  presented ‘Drug-drug interactions studies between HCV antivirals sofosbuvir/velpatasvir and HIV antiretrovirals’.  This was a Phase 1 study conducted in healthy volunteers to evaluate potential drug-drug interactions (DDIs) between SOF/VEL and HIV antiretroviral (ARV).

-       Increased TFV exposure (~40%) was observed with SOF/VEL when administered as TDF

-       Decreased velpatasvir (53%) when given with efavirenz

The author concluded that all study combinations could be used except efavirenz-containing ART.  This is an important finding given the number of patients taking Atripla.

And for the rare patients who does not achieve SVR with DAA therapy with sofosbuvir/ledipasvir (Harvoni)?  Well they can be retreated with…. Harvoni for 6 months combined with ribavirin.   Annie Luetkemeyer  (WEPEB060) presented data on 9 HIV/HCV who had not cleared with 12 weeks of Harvoni who were then retreated with 8/9 achieving a SVR.