Bictegravir approved in the US in new integrase-inhibitor based FDC (Biktarvy)
Simon Collins, HIV i-Base
On 7 February 2018, the US FDA approved a new fixed dose combination (FDC) containing bictegravir, emtricitabine and tenofovir alafenamide (TAF). [1, 2]
Bictegravir is an integrase inhibitor with a 50 mg dose that does not need to be boosted or taken with food. It is coformulated with 200 mg emtricitabine and a 25 mg dose of TAF.
Bictegravir has a plasma half-life of 18 hours, which suggests some flexibility for adherence and a resistance profile that might retain sensitivity to resistance mutations associated with raltegravir and elvitegravir but that is similar to dolutegravir. 
Approval is based on results from four ongoing randomised phase 3 studies.
The FDC is manufactured by Gilead Sciences and will be marketed with the brand name Bictarvy.
For more details please see the full prescribing information. 
Faster US approval was due to a Priority Review designation, that enables companies to buy and submit vouchers for an FDA decision with six rather than ten months.
This FDC has already been submitted to the EMA for European approval, with a decision expected later in 2018.
Pricing information was not included in the press release but will play a key role in uptake of the bictegravir FDC, given that dolutegravir is coformulated with two off-patent NRTIs and ViiV Healthcare have ongoing studies using dolutegravir with only lamivudine.
Almost immediately after the bictegravir FDC approval, ViiV Healthcare announced plans for a study that is not yet even listed on the clinical trials registry. This will switch people who are stable on TAF-containing combinations to dolutegravir/lamivudine dual therapy. 
Also following the approval, ViiV filed a lawsuit alleging that Gilead was infringing dolutegravir patents. ViiV is seeking “financial redress”. 
- FDA HIV listserv. FDA approves BIKTARVY tablets (Fixed Dose Combination). (07 February 2018).
- U.S. Food and Drug Administration approves Gilead’s Biktarvy (bictegravir, emtricitabine, tenofovir alafenamide) for treatment of HIV-1 infection. (07 February 2018).
- Tsiang M et al. Antiviral activity of bictegravir (GS-9883), a novel potent HIV-1 integrase strand transfer inhibitor with an improved resistance profile. Antimic Agents and Chem. (September 2016). doi: 10.1128/AAC.01474-16.
- Biktarvy US prescribing information and patient leaflet.
- ViiV press release. ViiV Healthcare launches eighth phase III study in two-drug regimen programme for HIV-1 treatment. (08 February 2018).
- Beasley D. US FDA approves Gilead triple HIV drug, rival files lawsuit. Reuters. 7 February 2017.