Company Announcements

• In largest head-to-head randomized clinical trial evaluating the two medicines, Dovato (DTG/3TC) met the primary endpoint, demonstrating sustained non-inferior efficacy versus Biktarvy (BIC/FTC/TAF) in virologically suppressed adults who switched from their prior regimen
• In latest data, Dovato led to significantly less weight gain and fewer drug-related adverse events compared to BIC/FTC/TAF through two years of follow-up

DURHAM, N.C.--(BUSINESS WIRE)--Oct. 17, 2025-- ViiV Healthcare, the global specialist HIV company majority owned by GSK, with Pfizer and Shionogi as shareholders, today announced 96-week findings from PASO DOBLE (GeSIDA 11720 study) showing that Dovato (dolutegravir/lamivudine [DTG/3TC]) is as effective as Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide fumarate [BIC/FTC/TAF]) in maintaining virological suppression in adults with HIV-1. Individuals taking Dovato also experienced statistically significant less weight gain and fewer drug-related adverse events over the two-year study period. Results will be presented at the European AIDS Clinical Society (EACS) annual congress, held in Paris, France (15-18 October).

PASO DOBLE is the largest head-to-head, phase IV randomized clinical trial investigating the two-drug regimen Dovato compared to the three-drug regimen BIC/FTC/TAF for the treatment of HIV-1 in people who are virologically suppressed and could benefit from treatment optimization. Results at 96 weeks showed patients who switched to Dovato achieved non-inferior efficacy in maintaining viral suppression compared with switching to BIC/FTC/TAF.^1,2

Jean van Wyk, MBChB, MFPM, Chief Medical Officer at ViiV Healthcare, said: "For people living with HIV, achieving and maintaining viral suppression remains the cornerstone of effective treatment. However, HIV treatment options have now advanced to where we can also look to other health metrics to help define success. The 96-week results from PASO DOBLE provide long-term findings that show Dovato continues to deliver robust viral control as effectively as a three-drug regimen, and people taking Dovato also experienced less weight gain compared to those taking Biktarvy. ViiV Healthcare remains committed to developing innovative, patient-centric treatment options that are not only effective with a good safety profile, but also address the needs of the community, beyond viral suppression."

In the PASO DOBLE clinical trial, 553 people living with HIV who were virally suppressed switched treatment to either Dovato (n=277) or BIC/FTC/TAF (n=276).¹ The study population included individuals who were on therapy that could be optimized, such as multiple tablet regimens, or those containing pharmacokinetic boosting agents or drugs with cumulative toxicity, such as efavirenz (EFV) or tenofovir disoproxil fumarate (TDF). The study met its primary endpoint, with Dovato demonstrating sustained non-inferior efficacy versus BIC/FTC/TAF based on the proportion of participants with HIV-1 RNA ≥50 copies/mL at 96 weeks using the FDA snapshot and a 4% non-inferiority margin in the exposed intention-to-treat population.¹

Esteban Martínez, MD, PhD, Chief Executive Investigator of the PASO DOBLE study and Senior Consultant in Infectious Diseases at Hospital Clínic of Barcelona, Spain said: "This 96-week data from PASO DOBLE underscores a favorable profile for Dovato, particularly regarding weight gain, which is an important consideration for virologically suppressed adults that may be on treatment for decades. Longer-term data for a two-drug regimen is crucial for HCPs and people living with HIV as they work together to make informed treatment decisions, considering long-term health management, beyond just viral suppression.”

At 96 weeks, Dovato was non-inferior to BIC/FTC/TAF (risk difference between Dovato [0.4%] minus BIC/FTC/TAF [1.1%] of –0.7%, 95% CI –2.1 to 0.7) in the maintenance of viral suppression. Three participants in the BIC/FTC/TAF arm and zero in the Dovato arm had protocol-defined virological failure through week 96 (HIV-1 RNA≥50 c/mL, followed by a second consecutive HIV-1 RNA assessment≥200 c/mL); no resistance was observed in any cases of virological failure.¹ These findings showed an increase of two new virologic failures in the BIC/FTC/TAF arm since the initially reported 48-week findings.^1,2

The trial was powered to assess weight gain as a key secondary endpoint. Data showed a statistically significant mean adjusted increase in weight gain with BIC/FTC/TAF (2.35kg, 95% CI 1.61–3.09) compared to Dovato (0.84kg, 95% CI 0.09–1.60) [difference: 1.52kg, 95% CI 0.74–2.29] through week 96.¹ The findings also showed the mean adjusted weight gain difference between arms increased from 1.13kg at 48 weeks (95% CI 0.37-1.89) to 1.52kg at 96 weeks (95% CI 0.74-2.29).^1,2 A significantly higher proportion of participants experienced a greater than 5% weight increase on BIC/FTC/TAF (34.8%) compared to Dovato (20.1%) (adjusted OR 2.05, 95% CI 1.37–3.07).¹

The study also found that drug-related adverse events were less frequent with Dovato (7.6%) as compared to BIC/FTC/TAF (13.4%) (p=0.025). Six participants discontinued treatment due to adverse events, mainly neuropsychiatric (Dovato [n=2] vs BIC/FTC/TAF [n=4]), with no significant differences between arms (p=0.409).¹

About PASO DOBLE
The PASO DOBLE (NCT04884139) randomized clinical trial is a phase IV, open-label, randomized multicenter clinical trial evaluating the efficacy of DTG/3TC versus BIC/FTC/TAF for the maintenance of virologic suppression in people living with HIV-1, conducted in 30 sites across Spain. Virologically suppressed people living with HIV-1 on regimens containing ≥1 pill/day, boosters, or drugs with cumulative toxicity such as efavirenz or TDF were eligible and were randomized (1:1) to switch to either DTG/3TC or BIC/FTC/TAF. The primary endpoint was virologic suppressions in people living with HIV-1 with RNA ≥50 copies/mL at 48 weeks (FDA snapshot, 4% non-inferiority margin) in the intention-to-treat exposed population. Secondary outcomes measured included, among others, absolute weight gain, BMI change, and the proportion of participants with weight change greater than 5%.

DOVATO (dolutegravir and lamivudine) tablets

INDICATION

DOVATO is indicated as a complete regimen for the treatment of HIV-1 infection in adults and adolescents 12 years of age and older and weighing at least 25 kg with no antiretroviral treatment history or to replace the current antiretroviral regimen in those who are virologically suppressed (HIV-1 RNA less than 50 copies/mL) on a stable antiretroviral regimen with no history of treatment failure and no known substitutions associated with resistance to the individual components of DOVATO.

IMPORTANT SAFETY INFORMATION

BOXED WARNING: PATIENTS CO-INFECTED WITH HEPATITIS B VIRUS (HBV) AND HIV-1: EMERGENCE OF LAMIVUDINE-RESISTANT HBV AND EXACERBATIONS OF HBV

All patients with HIV-1 should be tested for the presence of HBV prior to or when initiating DOVATO. Emergence of lamivudine-resistant HBV variants associated with lamivudine-containing antiretroviral regimens has been reported. If DOVATO is used in patients co-infected with HIV-1 and HBV, additional treatment should be considered for appropriate treatment of chronic HBV; otherwise, consider an alternative regimen.

Severe acute exacerbations of HBV have been reported in patients who are co-infected with HIV-1 and HBV and have discontinued lamivudine, a component of DOVATO. Closely monitor hepatic function in these patients and, if appropriate, initiate anti-HBV treatment.

Contraindications

• Do not use DOVATO in patients with previous hypersensitivity reaction to dolutegravir or lamivudine
• Do not use DOVATO in patients receiving dofetilide

Warnings and precautions

Hypersensitivity Reactions:

• Hypersensitivity reactions have been reported with dolutegravir and were characterized by rash, constitutional findings, and sometimes organ dysfunction, including liver injury
• Discontinue DOVATO immediately if signs or symptoms of severe skin or hypersensitivity reactions develop, as a delay in stopping treatment may result in a life-threatening reaction. Clinical status, including liver aminotransferases, should be monitored and appropriate therapy initiated

Hepatotoxicity:

• Hepatic adverse events have been reported, including cases of hepatic toxicity (elevated serum liver biochemistries, hepatitis, and acute liver failure), in patients receiving a dolutegravir-containing regimen without pre-existing hepatic disease or other identifiable risk factors
• Patients with underlying hepatitis B or C or marked elevations in transaminases prior to treatment may be at increased risk for worsening or development of transaminase elevations with use of DOVATO. In some cases, the elevations in transaminases were consistent with immune reconstitution syndrome or hepatitis B reactivation, particularly in the setting where anti-hepatitis therapy was withdrawn
• Monitoring for hepatotoxicity is recommended

Lactic Acidosis and Severe Hepatomegaly With Steatosis:

Fatal cases have been reported with the use of nucleoside analogs, including lamivudine. Discontinue DOVATO if clinical or laboratory findings suggestive of lactic acidosis or pronounced hepatotoxicity develop, including hepatomegaly and steatosis in the absence of marked transaminase elevations.

Adverse Reactions or Loss of Virologic Response Due to Drug Interactions with concomitant use of DOVATO and other drugs may occur (see Contraindications and Drug interactions).

Immune Reconstitution Syndrome, including the occurrence of autoimmune disorders with variable time to onset, has been reported with the use of DOVATO.

Adverse reactions

The most common adverse reactions (incidence ≥2%, all grades) with DOVATO were headache (3%), nausea (2%), diarrhea (2%), insomnia (2%), fatigue (2%), and anxiety (2%).

Drug interactions

• Consult full Prescribing Information for DOVATO for more information on potentially significant drug interactions
• DOVATO is a complete regimen. Coadministration with other antiretroviral medications for the treatment of HIV-1 infection is not recommended
• Drugs that induce or inhibit CYP3A or UGT1A1 may affect the plasma concentrations of dolutegravir
• Administer DOVATO 2 hours before or 6 hours after taking polyvalent cation-containing antacids or laxatives, sucralfate, oral supplements containing iron or calcium, or buffered medications. Alternatively, DOVATO and supplements containing calcium or iron can be taken with food

Use in specific populations

• Pregnancy: There are insufficient human data on the use of DOVATO during pregnancy to definitively assess a drug-associated risk for birth defects and miscarriage. An Antiretroviral Pregnancy Registry has been established.
• Lactation: Potential risks of breastfeeding include HIV-1 transmission, developing viral resistance in HIV-positive infants, and adverse reactions in a breastfed infant
• Renal Impairment: DOVATO is not recommended for patients with creatinine clearance <30 mL/min. Patients with a sustained creatinine clearance between 30 and 49 mL/min should be monitored for hematologic toxicities, which may require a dosage adjustment of lamivudine as an individual component
• Hepatic Impairment: DOVATO is not recommended in patients with severe hepatic impairment (Child-Pugh Score C)

For more information, please see full US Prescribing Information for DOVATO: https://gskpro.com/content/dam/global/hcpportal/en_US/Prescribing_Information/Dovato/pdf/DOVATO-PI-PIL.PDF

Trademarks are owned by or licensed to the ViiV Healthcare group of companies.

About SEIMC-GeSIDA Foundation (FSG)
The SEIMC-GeSIDA Foundation (FSG) was created to encourage, promote, and support scientific and technical research and development, training, and publication of findings in the field of clinical microbiology and infectious diseases and associated conditions.

FSG was founded by investigators from the Spanish Society of Clinical Microbiology and Infectious Diseases as a tool to promote high-quality investigation in the field of HIV infection and other infectious diseases. The Foundation also aims to respond to the scientific concerns of the group’s members.

FSG is composed of qualified professionals with experience in the field of clinical trials and multicenter studies. Its streamlined infrastructure facilitates performance of clinical studies and responds to the needs of investigators in terms of methodology/statistical analysis and of logistics and management of trials and other multicenter studies.

We also provide staff to run events such as scientific meetings and conferences (national and international) and to organize courses, lectures, talks, seminars, round-table talks, and specialized workshops.

For more information on the FSG, please visit https://fundacionseimcgesida.org/en/quienes-somos/

About ViiV Healthcare
ViiV Healthcare is a global specialist HIV company established in November 2009 by GSK (LSE: GSK) and Pfizer (NYSE: PFE) dedicated to delivering advances in treatment and care for people living with HIV and for people who could benefit from HIV prevention. Shionogi became a ViiV shareholder in October 2012. The company’s aims are to take a deeper and broader interest in HIV and AIDS than any company has done before and take a new approach to deliver effective and innovative medicines for HIV treatment and prevention, as well as support communities affected by HIV.

For more information on the company, its management, portfolio, pipeline, and commitment, please visit viivhealthcare.com.

About GSK
GSK is a global biopharma company with a purpose to unite science, technology, and talent to get ahead of disease together. Find out more at gsk.com.

Cautionary statement regarding forward-looking statements
GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the “Risk Factors” section in GSK’s Annual Report on Form 20-F for 2024, and GSK’s Q2 Results for 2025.

References

1. M. Masia, et al. Virological non-inferiority and lower weight gain with DTG/3TC versus BIC/FTC/TAF: 96-week final results from the PASO-DOBLE (GeSIDA 11720) randomised, multicentre, open-label, non-inferiority trial. Presented at the European AIDS Clinical Society (EACS) annual conference. October 2025
2. P. Ryan, et al. Non-inferior efficacy and less weight gain when switching to DTG/3TC than when switching to BIC/FTC/TAF in virologically suppressed people with HIV (PWH): the PASODOBLE (GeSIDA 11720) randomised clinical trial. Presented at the 25th International AIDS Conference. July 2024

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Source: ViiV Healthcare