Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide) and Dovato (dolutegravir/lamivudine) are both once-daily, single-tablet regimens recommended by DHHS as preferred first-line treatment for adults with HIV-1. Both achieve viral suppression in the large majority of treatment-naive patients. So how do you choose between them?
The answer depends on your resistance history, comorbidities, pregnancy status, neuropsychiatric history, and whether you have hepatitis B co-infection. This guide walks through every meaningful clinical difference so you can have an informed conversation with your HIV specialist.
- Both are DHHS preferred — neither is categorically superior for all patients
- Resistance testing is mandatory for Dovato — but not required before starting Biktarvy
- Biktarvy covers hepatitis B; Dovato does not — critical in HIV/HBV co-infection
- Dovato has more neuropsychiatric side effects — a DTG class effect affecting a minority of patients
- Biktarvy is preferred in pregnancy — DTG carries a small neural tube defect risk at conception
- Weight gain differs modestly — Dovato associated with somewhat more weight gain in trial data
- Neither has a US generic — both have manufacturer programs that can reduce cost to $0
Head-to-Head Comparison
| Feature | Biktarvy | Dovato |
|---|---|---|
| Active components | BIC + FTC + TAF (3 drugs) | DTG + 3TC (2 drugs) |
| Drug class | INSTI + 2 NRTIs | INSTI + 1 NRTI |
| FDA approved | 2018 | 2019 |
| Viral suppression at 48 wks | ~90–92% | ~91% |
| Resistance barrier | Very high (BIC) | High (DTG) |
| Baseline resistance test required | No | Yes (NRTI + INSTI) |
| HBV co-infection coverage | Yes (FTC + TAF active vs HBV) | No (3TC alone insufficient) |
| Weight gain (yr 1 median) | +2–3 kg | +3–5 kg |
| Neuropsychiatric effects | Low rate | Moderate (DTG class effect) |
| Pregnancy / childbearing | DHHS preferred | Caution — DTG neural tube defect risk |
| Renal / bone profile | Favorable (TAF) | Favorable (no tenofovir) |
| US WAC list price/month | ~$4,216 | ~$3,900 |
| DHHS first-line recommendation | ✓ Yes | ✓ Yes |
How Each Drug Works
Both regimens are anchored by an integrase strand transfer inhibitor (INSTI). INSTIs block the integration of HIV DNA into the host cell’s genome, a required step in viral replication. Where they diverge is in their nucleoside backbone.
Biktarvy: Bictegravir + Emtricitabine + Tenofovir Alafenamide
Bictegravir (BIC) is a second-generation INSTI with an exceptionally high genetic barrier to resistance. In Phase 3 trials, no treatment-emergent resistance to bictegravir was detected through 144 weeks of follow-up. Both FTC and TAF are active against hepatitis B, making Biktarvy the preferred choice in HIV/HBV co-infection.
Dovato: Dolutegravir + Lamivudine
Dolutegravir (DTG) is a second-generation INSTI with a high — though incrementally lower than BIC — genetic barrier to resistance. Lamivudine (3TC) is the sole NRTI component with a favorable renal and bone profile since it contains no tenofovir. However, lamivudine alone is not sufficient antiviral coverage for hepatitis B, and baseline resistance testing is mandatory before initiating Dovato.
Efficacy: How Well Does Each Work?
Biktarvy Clinical Evidence
Phase 3 trials GS-US-380-1489 and GS-US-380-1490 showed Biktarvy achieved viral suppression in approximately 89–92% of treatment-naive adults at week 48. The landmark finding: zero treatment-emergent resistance through 144 weeks. Long-term extension data through 5 years confirmed suppression rates of 86–89% with continued zero resistance emergence.
Dovato Clinical Evidence
The GEMINI-1 and GEMINI-2 trials demonstrated Dovato achieved viral suppression in approximately 91% of treatment-naive adults at week 48, non-inferior to dolutegravir plus TDF/FTC. Baseline resistance testing before prescribing Dovato is mandatory, not optional.
Clinical note: Dovato is not recommended in patients with known or suspected NRTI resistance mutations — particularly M184V/I (lamivudine resistance) — or in patients who have not completed baseline resistance testing. Biktarvy does not carry this restriction.
Side Effects
| Side Effect | Biktarvy | Dovato |
|---|---|---|
| Nausea on initiation | Occasional (≤5%) | More common (up to 15%) |
| Weight gain (yr 1 median) | +2–3 kg | +3–5 kg |
| Insomnia / sleep disturbance | Rare | More common (DTG class effect) |
| Depression / mood changes | Rare | More common (DTG class effect) |
| Abnormal dreams | Rare | Occasional (DTG class effect) |
| Bone density impact | Minimal (TAF profile) | Minimal (no tenofovir) |
| Discontinuation due to AEs | <1% in trials | <1% in trials |
For patients with a psychiatric history or sleep difficulties: Biktarvy is generally better tolerated neuropsychiatrically. For most users, Dovato’s neuropsychiatric effects are mild and transient — but disclose any psychiatric history to your prescriber before starting either drug.
Drug Interactions
Interactions Shared by Both Drugs
- Polyvalent cations (antacids, calcium, magnesium, iron, zinc supplements) chelate both bictegravir and dolutegravir, reducing absorption
- Rifampin / rifapentine — strong CYP inducers substantially reduce INSTI exposure; not recommended with either regimen
- Dofetilide — contraindicated with both drugs
- Metformin — both BIC and DTG inhibit OCT2 and MATE transporters, increasing metformin exposure
Dovato-Specific Interactions
- Oral sorbitol — high doses significantly reduce lamivudine absorption; avoid high-sorbitol co-administration
Pregnancy and Childbearing Potential
Dolutegravir has been associated with a small but statistically significant increase in neural tube defects when taken at or around the time of conception (approximately 0.3% vs 0.1% in unexposed pregnancies, Zash et al., NEJM 2019). NTDs form in the first 28 days of pregnancy, often before a person knows they are pregnant.
DHHS guidelines list Biktarvy as the preferred regimen for people of childbearing potential who are not using reliable contraception.
If you are of childbearing potential and not using reliable contraception: Discuss your regimen choice with your HIV specialist before starting either drug. Do not stop or switch any antiretroviral medication without medical guidance.
Hepatitis B Co-Infection
Biktarvy is preferred in HIV/HBV co-infection. Both FTC and TAF are active against hepatitis B. Dovato should not be used as the sole antiviral treatment in patients with active HBV co-infection without an additional HBV-active agent. Lamivudine alone is insufficient HBV coverage.
Always disclose hepatitis B status to your HIV specialist before initiating or changing any antiretroviral regimen. Stopping an HBV-active drug like TDF or TAF without a bridge strategy can cause serious hepatitis flare.
Who Should Consider Each Regimen
Biktarvy May Be Preferred When:
- Baseline resistance testing is pending — Biktarvy can be started immediately
- The patient has HIV/HBV co-infection
- There is a psychiatric history, sleep difficulties, or anxiety
- The patient is pregnant or of childbearing potential not using reliable contraception
Dovato May Be Preferred When:
- Baseline resistance testing confirms no NRTI or INSTI resistance
- Minimizing total antiretroviral drug exposure is a clinical goal
- The patient prefers to avoid tenofovir entirely
Cost Comparison
| Cost Factor | Biktarvy | Dovato |
|---|---|---|
| US WAC list price/month | ~$4,216 | ~$3,900 |
| Commercially insured + copay card | $0–$5/mo | $0–$5/mo |
| PAP (uninsured) | $0 (Gilead Advancing Access) | $0 (ViiV Positive Pathways) |
| ADAP coverage | All 50 states + DC | All 50 states + DC |
| US generic available | No (patent to ~2036) | No |
For most commercially insured US patients, manufacturer copay programs bring monthly cost to $0 for both drugs. Uninsured patients should contact Gilead Advancing Access at 1-800-226-2056 for Biktarvy, or ViiV Healthcare for Dovato. See our complete guide to Biktarvy cost without insurance.
Frequently Asked Questions
Neither is universally better — both achieve equivalent viral suppression in eligible patients. Biktarvy has a higher resistance barrier and does not require pre-treatment resistance testing, making it a safer choice when resistance history is unknown. Dovato may be preferred in patients with confirmed susceptible virus who want fewer antiretroviral components or wish to avoid tenofovir. The best regimen depends on individual clinical factors.
Clinical trial and real-world data consistently show Dovato is associated with somewhat greater weight gain — median gains of 3–5 kg in year one versus 2–3 kg with Biktarvy. Individual responses vary widely based on baseline weight, sex, ethnicity, and immune status. Neither drug should be avoided based on weight concern alone without a full metabolic risk assessment.
Yes, in appropriate patients. DHHS guidelines support switching from Biktarvy to Dovato in virologically suppressed adults with no resistance history, confirmed by prior genotypic testing. The switch must be managed by an HIV specialist after reviewing the full resistance profile, since lamivudine in Dovato is vulnerable to the M184V/I mutation if prior NRTI resistance is present.
There is significant overlap: both chelate polyvalent cations (antacids, iron, calcium supplements), both are affected by strong CYP inducers like rifampin, and both are contraindicated with dofetilide. Both also inhibit OCT2 transporters, raising metformin levels. Biktarvy has additional P-gp interactions; Dovato has a unique interaction with oral sorbitol-containing medications.
Dovato’s US WAC is modestly lower (~$3,900/month versus ~$4,216/month for Biktarvy). In practice, manufacturer copay programs bring out-of-pocket cost to $0 for most commercially insured patients on either drug. For uninsured patients, both are available through manufacturer PAP programs and state ADAP. Neither has a US generic.
Dolutegravir — the integrase inhibitor in Dovato — has been associated with a small but measurable increase in neural tube defects when taken at the time of conception. DHHS guidelines list Biktarvy as the preferred regimen for people of childbearing potential who are not on reliable contraception. If pregnancy is confirmed after neural tube closure (approximately 6 weeks gestation), dolutegravir-containing regimens may often be continued with specialist guidance.
Biktarvy is preferred in HIV/HBV co-infection because both FTC and TAF are active against hepatitis B. Dovato contains only lamivudine, which alone is not sufficient HBV coverage. Starting Dovato in a patient with active HBV co-infection without additional HBV-active medication risks a serious hepatitis B flare. Always disclose HBV status to your HIV specialist before initiating any regimen.
Yes, dolutegravir has a well-documented class effect of neuropsychiatric side effects including insomnia, vivid dreams, anxiety, and in some patients depression or cognitive difficulties. These usually affect a minority of users and often resolve within weeks. Bictegravir shows a notably lower rate of neuropsychiatric effects. For patients with a psychiatric history or sleep difficulties, Biktarvy is generally better tolerated in this regard.
Medically reviewed by Dr. Ranjit Mohan, MD, Infectious Disease Specialist
Written by Ana Goios
How we reviewed this article: Sunny Pharma follows strict sourcing guidelines and relies on peer-reviewed studies, government agencies (FDA, DHHS, WHO), academic research institutions, and medical associations. Learn more in our editorial policy.
Sources & References
- Gallant J, et al. Bictegravir, emtricitabine, and tenofovir alafenamide versus dolutegravir, abacavir, and lamivudine (GS-US-380-1489). Lancet. 2017.
- Cahn P, et al. Dolutegravir plus lamivudine versus dolutegravir plus TDF/FTC (GEMINI-1 and GEMINI-2). Lancet. 2019;393(10167):143–155.
- US DHHS Panel on Antiretroviral Guidelines. Updated 2025: clinicalinfo.hiv.gov
- FDA Biktarvy Prescribing Information (2025): accessdata.fda.gov
- ViiV Healthcare. Dovato (dolutegravir/lamivudine) Prescribing Information. 2023: viivhealthcare.com
- Zash R, et al. Neural-tube defects and antiretroviral treatment regimens in Botswana. N Engl J Med. 2019;381:827–840.
- Sax PE, et al. Weight gain following initiation of antiretroviral therapy. Clin Infect Dis. 2020;71(6):1379–1389.