Chloe Orkin presented a case for consideration in relation to what ART to start. She then presented data comparing the different global guidelines and their recommended regimens. The important point highlighted here was the fact that a number of the guidelines for the management of HIV infection have recently been updated in 2018. The BHIVA guidelines are currently in the process of being updated.
One of the key learnings from this session was that globally there has now been a move to use Integrase Strand Transfer Inhibitor (INSTI) regimens first line. One of the major changes identified was that the WHO 2018 Antiretroviral Guidelines now list dolutegravir (DTG) in combination with 2 nucleoside reverse transcriptase inhibitors (NRTIs) for first line therapy.
Of particular relevance to Australia was the DHHS Guidelines update that had occurred on 25th October 2018, just prior to HIV Glasgow 2018. These guidelines now recommend the following regimens for initial therapy for most people with HIV:
-
Bictegravir/tenofovir alafenamide/emtricitabine (Biktarvy)
-
Dolutegravir/abacavir/lamivudine (Triumeq)
-
Dolutegravir + tenofovir/emtricitabine (TAF/FTC or TDF/FTC)
-
Raltegravir + tenofovir/emtricitabine (TDF/FTC or TAF/FTC)
A further key learning from this session was the information that globally there has been a move away from elvitegravir as a preferred INSTI. In the DHHS Guidelines, the Single Tablet Regimens: elvitegravir/cobicistat/tenofovir alafenamide/emtricitabine (Genvoya) and elvitegravir/cobicistat/tenofovir disoproxil fumarate/emtricitabine (Stribild) have been moved from the status of being an initial regimen for most people with HIV, to recommended initial regimens in certain clinical situations. This change relates to the need to use the pharmacoenhancer cobicistat with elvitegravir, and the consequence of increased likelihood of drug-drug interactions due to cobicistat use. Elvitegravir also has a lower barrier to resistance than dolutegravir or bictegravir.
As a consequence of these recent changes to the DHHS guidelines, the Australian Antiretroviral Guidelines will ultimately need to be updated. Currently however one of the updated guidelines recommended Single Tablet Regimens, Biktarvy, is not available in Australia. Biktarvy has been approved by the Therapeutic Goods Administration (TGA), but is yet to be listed on the Pharmaceutical Benefits Scheme (PBS).
Once Biktarvy is available it will provide another therapeutic option for patients, and the changes to the guidelines would be expected to change the options considered for first line therapy for patients. In terms of my practice, although elvitegravir is now seen as a less favourable INSTI we will shortly gain access to the new INSTI bictegravir in Biktarvy. A new medication brings with it a lot of knowledge that needs to acquired, and clinical experience in using the medication that needs to be gained. Although bictegravir has the advantage that it doesn’t require a booster, it still has drug-drug interactions which will need to be considered in patient care. It would also be expected that some patients currently taking Genvoya may be switched to Biktarvy when available. In these situations it is going to be important to consider the impact of ceasing Genvoya and commencing Biktarvy, especially on any other concomitant medications that patients may be taking, from a drug-drug interaction perspective.
Author bio:
Fiona trained as a pharmacist in UK prior to moving to Australia in 1997. She has been working as a clinical pharmacist in the area of HIV/Sexual Health on the Gold Coast since 1998. She was involved in a pilot of pharmacist prescribing for patients with HIV infection in 2009-2010. She is contacted for advice by health professionals external to the Gold Coast, and has provided advice in relation to adults, adolescents and children with HIV infection.
