GSK's Dovato Matches Gilead's Biktarvy in First Head-to-Head HIV Trial (VOGUE)

ViiV Healthcare presented the first randomized head-to-head data showing its 2-drug HIV regimen Dovato matches Gilead’s 3-drug Biktarvy in treatment-naïve adults. The Phase 3b VOGUE trial, presented at the 26th International AIDS Conference in Rio de Janeiro on July 28, met its non-inferiority endpoint at Week 48.

GSK, which owns 78.3% of ViiV, closed at $53.71 on July 28. Gilead (GILD) closed at $134.32. Both companies reported Q2 earnings the same week, but the VOGUE data is the competitive story for the HIV franchise.

VOGUE randomized 509 treatment-naïve adults with HIV-1 to receive either Dovato (dolutegravir/lamivudine, n=254) or Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide, n=255). At Week 48, viral suppression (HIV-1 RNA below 50 copies/mL) was achieved in 89% of the Dovato arm versus 92% of the Biktarvy arm. The adjusted difference was -3 percentage points (95% CI: -8% to 2%), meeting the non-inferiority margin. Treatment was initiated before baseline resistance testing results were available, and zero treatment-emergent resistance emerged in either arm.

The trial enrolled a challenging population: 47% had viral loads at or above 100,000 copies/mL, 16% had viral loads at or above 500,000 copies/mL, and 16% had CD4+ counts below 200 cells/mm³. These are the high-risk subgroups where skeptics have questioned whether a 2-drug regimen can hold its own against a 3-drug regimen. VOGUE suggests it can.

Biktarvy generated $14.3 billion in 2025 sales for Gilead, making it the largest HIV drug in the world. Dovato brought in £2.7 billion ($3.6 billion) for ViiV in 2025. Gilead’s revenue advantage is roughly 4-to-1, but VOGUE gives ViiV the first direct evidence that fewer drugs can deliver equivalent outcomes in first-line therapy.

The argument for a 2-drug regimen is straightforward: fewer active agents mean lower long-term organ toxicity risk, a simpler daily pill, and potential cost savings for healthcare systems. The counterargument has been that 3-drug regimens offer a wider resistance barrier. VOGUE’s zero resistance result in both arms undercuts that concern, at least at 48 weeks.

Why does this matter now? Gilead and Merck are developing a once-weekly oral HIV pill combining islatravir and lenacapavir, which could shift the market toward long-acting regimens. Gilead’s lenacapavir is also advancing in twice-yearly PrEP. The HIV treatment field is moving away from daily orals, so VOGUE’s value is partly defensive: it gives Dovato a data-backed competitive position against Biktarvy while both franchises face disruption from long-acting alternatives.

The risk for GSK is that VOGUE’s 48-week data, while meeting non-inferiority, still shows a 3-point numerical gap favoring Biktarvy. Physicians who already prescribe Biktarvy may see no compelling reason to switch. The non-inferiority margin was wide enough that the trial cannot rule out a small real-world efficacy difference. Longer-term data and real-world switching studies will determine whether VOGUE actually moves prescribing patterns.

What to watch next: Gilead is expected to push back on the non-inferiority framing, emphasizing Biktarvy’s numerical edge and its longer real-world track record. The question is whether ViiV can convert VOGUE into formulary wins and new patient starts in a market where the entrenched leader has a 4-to-1 revenue advantage.