An ongoing dialogue on HIV/AIDS, infectious diseases,
September 28th, 2014
New FDA HIV Drug Approvals Unlikely to Have Much Impact, Unless …
If you’re an ID doc based in the USA, you probably received notice last week that two new HIV drugs were approved — cobicistat and elvitegravir.
And if you’re wondering what the big deal is, welcome to the club. In fact, the Canadians beat us to the punch with more significant approval, the co-formulated darunavir/cobicistat, branded as Prezcobix — which sounds like one favorite British breakfast cereal.
For the record, here are a few reasons why the FDA approval of elvitegravir and cobisistat will likely have little short-term effect on clinical practice:
- Elvitegravir is already available as part of TDF/FTC/EVG/COBI.
- Cobicistat is already available as part of the same single tablet regimen.
- If not coformulated, elvitegravir alone has no major advantages over raltegravir and dolutegravir.
- If not coformulated, cobicistat alone has no major advantages over ritonavir. (Though I gather the pill is smaller. Haven’t seen it yet.)
But — what if they cost less? Especially a lot less?
Then maybe.
I agree that these drugs will probably have very limited use; in addition to the reasons you cite, I think prescribers will be put off by the complicated dosing recommendations: Elvitegravir is only approved for use with BID darunavir, not once daily, and for BID fosamprenavir and tipranavir, which I’m sure almost no one will use. And for atazanavir and lopinavir/ritonavir we’ll have to remember to use the 85mg dose of elvitegravir, which is also problematic for some of us.