– Analyses of Bixlenvo™ (bictegravir 75 mg/lenacapavir 50 mg) Examine Outcomes in People with HIV and Selected Comorbidities or Renal Impairment –

– Real-World Evidence Provides Insight into Early U.S. Adoption of Yeztugo® (lenacapavir) for HIV PrEP –

– Phase 1b Data Highlight Virologic Efficacy, Safety and Tolerability of Investigational GS-1179 for Recurrent Genital Herpes –

Gilead Sciences, Inc. (Nasdaq: GILD) will present new findings from its HIV and antiviral research and development programs at IDWeek 2026, taking place October 21-24 in Washington, D.C. The 28 presentations, including two oral presentations, will feature research in HIV treatment, HIV prevention and new insights into broader experiences of people living with HIV, as well as emerging antiviral programs.

“We remain committed to advancing options for people affected by HIV and other serious diseases, as evidenced by the breadth of our research and antiviral pipeline,” said Jared Baeten, MD, PhD, Senior Vice President, Clinical Development, Virology Therapeutic Area Head, Gilead Sciences. “These findings span clinical research and real-world evidence, deepening our understanding of evolving needs and informing innovations that have the potential to make a meaningful difference for the communities we serve.”

HIV Treatment Research

New analyses from the Phase 3 ARTISTRY-1 and ARTISTRY-2 Studies will provide further insights into the safety and efficacy of Bixlenvo™ (bictegravir 75 mg/lenacapavir 50 mg), the smallest once-daily, single tablet regimen (STR) for the treatment of HIV in adults who are virologically suppressed, including those on complex regimens. New ARTISTRY-1 sub-analyses will provide insights into treatment outcomes among trial participants with comorbidities like dyslipidemia, hypertension, diabetes mellitus and renal impairment, building on data from the oldest study population in a Phase3 registrational trial for HIV-1 treatment to date. Findings from ARTISTRY-2 will examine metabolic and safety outcomes among people with HIV with selected baseline comorbidities.

Additional treatment research will examine virologic effectiveness, resistance and strategies for restarting antiretroviral therapy following interruptions in care, including studies in historically under-resourced communities and analyses of treatment patterns in real-world settings.

Data from the Phase 4 ACCELERATE Implementation Study will be presented on Biktarvy^® (bictegravir/emtricitabine/tenofovir alafenamide, B/F/TAF), examining rapid antiretroviral therapy (ART) restart for people with HIV returning to care.

HIV Prevention Research

Gilead will present research examining early real-world adoption of twice-yearly Yeztugo^® (lenacapavir) for HIV pre-exposure prophylaxis (PrEP) in the United States during the first nine months following approval by the U.S. Food and Drug Administration (FDA). Yeztugo is the only FDA-approved twice-yearly option for people who need or want PrEP.

Additional studies will examine factors that influence PrEP access, uptake and implementation, including provider education, linkage to prevention services, cost sharing and the potential economic and public health impact of expanded HIV prevention.

Herpes Simplex Virus (HSV) Research

Gilead will also present final results from a Phase 1b Study of Investigational GS-1179, an oral, long-acting herpes simplex virus (HSV) helicase-primase inhibitor being developed for suppression of recurrent genital herpes. The presentations will highlight findings on virologic efficacy, safety and tolerability.

Overview of Scientific Presentations

For more information about Gilead’s presence at IDWeek 2026, including a complete list of abstracts and their corresponding oral and poster sessions, please visit https://idweek.org/program/.

Bictegravir and lenacapavir in combination for HIV treatment is approved in the U.S. but is not approved by any regulatory authority outside of the U.S. Bixlenvo requires a two-day initiation dose with Sunlenca^® (lenacapavir), thereafter only Bixlenvo is taken orally once a day.

Bictegravir, emtricitabine, and tenofovir alafenamide in combination for HIV treatment is approved in the U.S., the EU, Canada, Australia, Japan, China, the UK, New Zealand and India.

Lenacapavir for HIV prevention as PrEP is approved in the U.S., the EU, Canada, Brazil, South Africa, Australia, Zambia and Zimbabwe.

Please see below for U.S. Indication and Important Safety Information, including Boxed Warning for Yeztugo and Biktarvy. Please also see below for the U.S. Indication and Important Safety Information for Bixlenvo.

There is currently no cure for HIV or AIDS.

About Bixlenvo

Bixlenvo is a once-daily, single tablet regimen that combines bictegravir, a global guideline-recommended integrase strand transfer inhibitor (INSTI) with a high barrier to resistance, and lenacapavir, a first-in-class capsid inhibitor with a multi-stage mechanism of action. Together, bictegravir and lenacapavir target multiple stages of the HIV life cycle. Developed for adults with HIV who are virologically suppressed, including those on complex regimens, Bixlenvo expands treatment choice with a simple daily oral option supported by results from the Phase 3 ARTISTRY clinical program. For more information, visit www.Bixlenvo.com.

About Lenacapavir

Lenacapavir is approved in multiple countries as pre-exposure prophylaxis (PrEP) to reduce the risk of sexually acquired HIV in adults and adolescents who are at risk of HIV acquisition. Lenacapavir is also approved in multiple countries for the treatment of multi-drug-resistant HIV in adults, in combination with other antiretrovirals.

The multi-stage mechanism of action of lenacapavir is distinguishable from other currently approved classes of antiviral agents. While most antivirals act on just one stage of viral replication, lenacapavir is designed to inhibit HIV at multiple stages of its life cycle and has no known cross resistance exhibited in vitro to other existing drug classes.

Lenacapavir is being evaluated as a long-acting option in multiple ongoing and planned early and late-stage clinical studies in Gilead’s HIV prevention and treatment research program. Lenacapavir is being developed as a foundation for potential future HIV therapies with the goal of offering both long-acting oral and injectable options with several dosing frequencies, in combination or as a mono agent, that help address individual needs and preferences of people and communities affected by HIV. The journal Science named lenacapavir its 2024 “Breakthrough of the Year.”

About Biktarvy

Biktarvy is a complete HIV treatment that combines three powerful medicines to form the smallest three-drug, integrase strand transfer inhibitor (INSTI)-based STR available, offering simple once-daily dosing with or without food, with a limited drug interaction potential and a high barrier to resistance. Biktarvy combines the novel, unboosted INSTI bictegravir, with the F/TAF backbone. Biktarvy is a complete STR and should not be taken with other HIV medicines. For more information, visit www.Biktarvy.com.

About GS-1179

GS-1179, formerly ABI-1179, is an investigational helicase-primase inhibitor being developed for HSV infections. It was advanced through early clinical stage development under Assembly Bio’s collaboration with Gilead. HSV helicase-primase inhibitors target an enzyme complex essential for viral replication and represent a mechanism distinct from currently available nucleoside analog therapies. GS-1179 was selected for advancement by Gilead in the HSV HPI program based on encouraging Phase 1b results and its potential to support once-weekly oral dosing.

U.S. Indication for Bixlenvo

Bixlenvo is indicated as a complete regimen for the treatment of HIV-1 infection in adults to replace the current antiretroviral regimen in those who are virologically suppressed (HIV-1 RNA less than 50 copies per mL) on a stable antiretroviral regimen with no known or suspected resistance to the individual components of Bixlenvo.

U.S. Important Safety Information for Bixlenvo

Contraindications

• Coadministration: Concomitant administration of Bixlenvo is contraindicated with dofetilide and strong CYP3A inducers.

Warnings and precautions

• See Contraindications and Drug Interactions sections. Consider the potential for drug interactions prior to and during Bixlenvo therapy and monitor for adverse reactions.

Adverse reactions

• Most common adverse reactions (incidence >2%; all grades) reported in clinical trials were headache (4%), nausea (3%), and diarrhea (2%).

Drug interactions

• Prescribing Information: Consult the full Prescribing Information for Bixlenvo for more information on contraindications, warnings, and potentially significant drug interactions, including clinical comments.
  • Enzymes/transporters: Drugs that are both a strong inducer of CYP3A and induce UGT1A1 can substantially decrease the concentration of components of Bixlenvo. Drugs that are strong or moderate inducers of CYP3A may significantly decrease the concentrations of components of Bixlenvo. Drugs that are both a strong CYP3A inhibitor and a UGT1A1 inhibitor, or combined P-gp, UGT1A1, and strong CYP3A inhibitors can significantly increase concentrations of components of Bixlenvo.

Dosage and administration

• Dosage: Two-day initiation regimen of Bixlenvo 1 tablet plus Sunlenca 2 tablets taken orally daily, followed by a maintenance regimen of Bixlenvo 1 tablet orally once daily. Tablets may be taken with or without food.
  • Day 1: Bixlenvo 1 tablet of 75 mg/50 mg orally AND Sunlenca 2 tablets of 300 mg orally (600 mg dose)
  • Day 2: Bixlenvo 1 tablet of 75 mg/50 mg orally AND Sunlenca 2 tablets of 300 mg orally (600 mg dose)
  • Day 3 and once daily thereafter: Bixlenvo 1 tablet of 75 mg/50 mg orally once daily
• Missed dose: If the initiation doses of Bixlenvo or Sunlenca are missed, patients should take them as soon as possible. Patients should not take both Day 1 and Day 2 doses of Sunlenca on the same day. Patients should take missed maintenance doses as soon as possible. If more than 7 days have elapsed since the last maintenance dose, restart initiation dosage regimen from Day 1, if clinically appropriate to continue treatment.

Pregnancy and lactation

• Pregnancy: Lower exposures of bictegravir were observed in clinical studies with a bictegravir-containing regimen. Therefore, viral load should be monitored closely in pregnant individuals. An Antiretroviral Pregnancy Registry (APR) has been established.
• Lactation: Individuals with HIV-1 should be informed of the potential risks of breastfeeding.

U.S. Indication for Yeztugo

Yeztugo (lenacapavir) injection, 463.5 mg/1.5 mL, is indicated for pre-exposure prophylaxis (PrEP) to reduce the risk of sexually acquired HIV-1 in adults and adolescents weighing at least 35 kg who are at risk for HIV-1 acquisition. Individuals must have a negative HIV-1 test prior to initiating Yeztugo.

U.S. Important Safety Information for Yeztugo

BOXED WARNING: RISK OF DRUG RESISTANCE WITH USE OF YEZTUGO IN UNDIAGNOSED HIV-1 INFECTION

• Individuals must be tested for HIV-1 infection prior to initiating YEZTUGO, and with each subsequent injection of YEZTUGO, using a test approved or cleared by the FDA for the diagnosis of acute or primary HIV-1 infection. Drug-resistant HIV-1 variants have been identified with use of YEZTUGO by individuals with undiagnosed HIV-1 infection. Do not initiate YEZTUGO unless negative infection status is confirmed. Individuals who acquire HIV-1 while receiving YEZTUGO must transition to a complete HIV-1 treatment regimen.

Contraindications

• YEZTUGO is contraindicated in individuals with unknown or positive HIV-1 status.

Warnings and precautions

• Comprehensive risk management:
  • Use YEZTUGO to reduce the risk of HIV-1 acquisition as part of a comprehensive prevention strategy including adherence to the administration schedule and safer sex practices, including condoms, to reduce the risk of sexually transmitted infections (STIs).
  • HIV-1 acquisition risk includes behavioral, biological, or epidemiologic factors including, but not limited to, condomless sex, past or present STIs, self-identified HIV risk, having sexual partners of unknown HIV-1 viremic status, or sexual activity in a high-prevalence area or network. Counsel individuals on the use of other prevention methods to help reduce their risk.
  • Use YEZTUGO only in individuals confirmed to be HIV-1 negative. Evaluate for current or recent signs or symptoms consistent with HIV-1 infection. Confirm HIV-1 negative status prior to initiating, prior to each subsequent injection, and as clinically appropriate.
• Potential risk of resistance:
  • There is a potential risk of developing resistance to YEZTUGO if an individual acquires HIV-1 before or when receiving YEZTUGO or following discontinuation. HIV-1 resistance substitutions may emerge in individuals with undiagnosed HIV-1 infection taking only YEZTUGO, because YEZTUGO alone is not a complete regimen for HIV-1 treatment.
  • To minimize this risk, it is essential to test before each injection and additionally as clinically appropriate. Individuals confirmed to have HIV-1 must immediately begin a complete HIV-1 treatment regimen.
  • Alternative forms of PrEP should be considered after discontinuation of YEZTUGO for those who are at continuing risk of HIV-1 acquisition and should be initiated within 28 weeks of the last YEZTUGO injection.
• Long-acting properties and potential associated risks:
  • Residual concentrations of YEZTUGO may remain in systemic circulation for up to 12 months or longer after the last injection.
  • Select individuals who agree to the required injection dosing schedule because nonadherence or missed doses could lead to HIV-1 acquisition and development of resistance.
• Serious injection site reactions: Improper administration (intradermal injection) has been associated with serious injection site reactions, including necrosis and ulcer. Only administer YEZTUGO subcutaneously.

Adverse reactions

• Most common adverse reactions (≥5%) in YEZTUGO clinical trials were injection site reactions, headache, and nausea.

Drug interactions

• Strong or moderate CYP3A inducers may significantly decrease YEZTUGO concentrations. Dosage modifications are recommended when initiating these inducers.
• It is not recommended to use YEZTUGO with combined P-gp, UGT1A1, and strong CYP3A inhibitors.
• Coadministration of YEZTUGO with sensitive substrates of CYP3A or P-gp may increase their concentrations and result in the increased risk of their adverse events. YEZTUGO may increase the exposure of drugs primarily metabolized by CYP3A initiated within 9 months after the last injection of YEZTUGO.

Dosage and administration

• HIV screening: Test for HIV-1 infection prior to initiating, prior to each subsequent injection, and as clinically appropriate using an approved or cleared test for the diagnosis of acute or primary HIV-1 infection.
• Dosage: Initiation dosing (injections and tablets) followed by once-every-6-months continuation injection dosing. Tablets may be taken with or without food.
• Initiation: Day 1: 927 mg by subcutaneous injection (2 x 1.5-mL injections) and 600 mg orally (2 x 300-mg tablets). Day 2: 600 mg orally.
• Continuation: 927 mg by subcutaneous injection every 6 months (26 weeks) from date of last injection ±2 weeks.
• Anticipated delayed injections: If scheduled 6-month injection is anticipated to be delayed by more than 2 weeks, YEZTUGO tablets may be taken on an interim basis (for up to 6 months) until injections resume. Dosage is 300 mg orally (1 x 300-mg tablet) once every 7 days. Resume continuation injections within 7 days of the last oral dose.
• Missed injections: If more than 28 weeks have elapsed since the last injection and YEZTUGO tablets have not been taken, restart with initiation dosing if clinically appropriate.
• Dosage modifications of YEZTUGO are recommended when initiating with strong or moderate CYP3A inducers. Consult the full Prescribing Information for recommendations.

U.S. Indication for Biktarvy

Biktarvy is indicated as a complete regimen for the treatment of HIV-1 infection in adult and pediatric patients weighing ≥14 kg with no antiretroviral treatment history; or with an ARV treatment history and not virologically suppressed, with no known or suspected substitutions associated with resistance to the integrase strand inhibitor class, emtricitabine, or tenofovir; or to replace the current ARV regimen in those who are virologically suppressed (HIV-1 RNA <50 copies per mL) on a stable ARV regimen with no known or suspected substitutions associated with resistance to bictegravir or tenofovir.

U.S. Important Safety Information for Biktarvy

BOXED WARNING: POST TREATMENT ACUTE EXACERBATION OF HEPATITIS B

• Severe acute exacerbations of hepatitis B have been reported in patients who are coinfected with HIV-1 and HBV and have discontinued products containing emtricitabine (FTC) and/or tenofovir disoproxil fumarate (TDF) and may occur with discontinuation of BIKTARVY. Closely monitor hepatic function with both clinical and laboratory follow-up for at least several months in patients who are coinfected with HIV-1 and HBV and discontinue BIKTARVY. If appropriate, anti-hepatitis B therapy may be warranted.

Contraindications

• Coadministration: Do not use BIKTARVY with dofetilide or rifampin.

Warnings and precautions

• Drug interactions: See Contraindications and Drug Interactions sections. Consider the potential for drug interactions prior to and during BIKTARVY therapy and monitor for adverse reactions.
• Immune reconstitution syndrome, including the occurrence of autoimmune disorders with variable time to onset, has been reported.
• New onset or worsening renal impairment: Postmarketing cases of renal impairment, including acute renal failure, proximal renal tubulopathy (PRT), and Fanconi syndrome have been reported with tenofovir alafenamide (TAF)–containing products. Do not initiate BIKTARVY in patients with estimated creatinine clearance (CrCl) <30 mL/min except in virologically suppressed adults <15 mL/min who are receiving chronic hemodialysis. Patients with impaired renal function and/or taking nephrotoxic agents (including NSAIDs) are at increased risk of renal-related adverse reactions. Discontinue BIKTARVY in patients who develop clinically significant decreases in renal function or evidence of Fanconi syndrome. Renal monitoring: Prior to or when initiating BIKTARVY and during therapy, assess serum creatinine, CrCl, urine glucose, and urine protein in all patients as clinically appropriate. In patients with chronic kidney disease, assess serum phosphorus.
• Lactic acidosis and severe hepatomegaly with steatosis: Fatal cases have been reported with the use of nucleoside analogs, including FTC and TDF. Discontinue BIKTARVY 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

• Most common adverse reactions (incidence ≥5%; all grades) in clinical studies through week 144 were diarrhea (6%), nausea (6%), and headache (5%).

Drug interactions

• Prescribing Information: Consult the full Prescribing Information for Biktarvy for more information on contraindications, warnings, and potentially significant drug interactions, including clinical comments.
• Enzymes/transporters: Drugs that induce P-gp or induce both CYP3A and UGT1A1 can substantially decrease the concentration of components of BIKTARVY. Drugs that inhibit P-gp, BCRP, or inhibit both CYP3A and UGT1A1 may significantly increase the concentrations of components of BIKTARVY. BIKTARVY can increase the concentration of drugs that are substrates of OCT2 or MATE1.
• Drugs affecting renal function: Coadministration of BIKTARVY with drugs that reduce renal function or compete for active tubular secretion may increase concentrations of FTC and tenofovir and the risk of adverse reactions.

Dosage and administration

• Dosage: Adult and pediatric patients weighing ≥25 kg: 1 tablet containing 50 mg bictegravir (BIC), 200 mg emtricitabine (FTC), and 25 mg tenofovir alafenamide (TAF) taken once daily with or without food. Pediatric patients weighing ≥14 kg to <25 kg: 1 tablet containing 30 mg BIC, 120 mg FTC, and 15 mg TAF taken once daily with or without food. For children unable to swallow a whole tablet, the tablet can be split and each part taken separately as long as all parts are ingested within approximately 10 minutes.
• Renal impairment: For patients weighing ≥25 kg, not recommended in patients with CrCl 15 to <30 mL/min, or <15 mL/min who are not receiving chronic hemodialysis, or <15 mL/min who are receiving chronic hemodialysis and have no antiretroviral treatment history. For patients weighing ≥14 kg to <25 kg, not recommended in patients with CrCl <30 mL/min.
• Hepatic impairment: Not recommended in patients with severe hepatic impairment.
• Prior to or when initiating: Test patients for HBV infection.
• Prior to or when initiating, and during treatment: As clinically appropriate, assess serum creatinine, CrCl, urine glucose, and urine protein in all patients. In patients with chronic kidney disease, assess serum phosphorus.

Pregnancy and lactation

• Pregnancy: BIKTARVY is recommended in pregnant individuals who are virologically suppressed on a stable ARV regimen with no known substitutions associated with resistance to any of the individual components of BIKTARVY. Lower plasma exposures of BIKTARVY were observed during pregnancy; therefore, viral load should be monitored closely during pregnancy. An Antiretroviral Pregnancy Registry (APR) has been established. Available data from the APR for BIC, FTC, or TAF show no difference in the rates of birth defects compared with a US reference population.
• Lactation: Individuals infected with HIV-1 should be informed of the potential risks of breastfeeding.

About Gilead HIV

For almost 40 years, Gilead has been a leading innovator in the field of HIV, driving advances in treatment, prevention and cure research. Gilead researchers have developed 14 HIV medications, including the first single tablet regimen to treat HIV, the first antiretroviral for pre-exposure prophylaxis (PrEP) to help reduce new HIV infections, and the first long-acting injectable HIV prevention medication administered twice-yearly. Our advances in medical research have helped to transform HIV into a treatable, preventable, chronic condition for millions of people.

Gilead is committed to continued scientific innovation to provide solutions for the evolving needs of people affected by HIV around the world. Through partnerships, collaborations and charitable giving, the company also aims to improve education, expand access and address barriers to care, with the goal of ending the HIV epidemic worldwide. Gilead has been repeatedly recognized as one of the top two leading philanthropic funders of HIV-related programs in a report released by Funders Concerned About AIDS.

Discover more about Gilead’s unique collaborations worldwide and the work to help end the HIV epidemic at www.GileadHIV.com.

About Gilead Sciences

Gilead Sciences, Inc. is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades, with the goal of creating a healthier world for all people. The company is committed to advancing innovative medicines to prevent and treat life-threatening diseases, including HIV, viral hepatitis, COVID-19, cancer and inflammation. In 2025, Gilead announced a $32 billion investment to further strengthen its U.S. footprint to power the next era of discovery, job creation and public health preparedness – while continuing to invest globally to ensure patients everywhere benefit from its scientific innovation. Gilead operates in more than 35 countries worldwide, with headquarters in Foster City, Calif.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including Gilead’s ability to initiate, progress or complete clinical trials or studies within currently anticipated timelines or at all, and the possibility of unfavorable results from ongoing and additional clinical trials or studies, including those involving bictegravir, lenacapavir and GS-1179 (such as ARTISTRY-1, ARTISTRY-2 and ACCELERATE); uncertainties relating to regulatory applications and related filing and approval timelines, including potential applications for programs and/or indications currently under evaluation, and the risk that any regulatory approvals, if granted, may be subject to significant limitations on use or subject to withdrawal or other adverse actions by the applicable regulatory authority; the possibility that Gilead may make a strategic decision to discontinue development of these programs and, as a result, these programs may never be successfully commercialized for the indications currently under evaluation; and any assumptions underlying any of the foregoing. These and other risks, uncertainties and factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2026, as filed with the U.S. Securities and Exchange Commission. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. The reader is cautioned that any such forward-looking statements are not guarantees of future performance and involve risks and uncertainties and is cautioned not to place undue reliance on these forward-looking statements. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation and disclaims any intent to update any such forward-looking statements.

IDWeek 2026™ is an annual meeting of the Infectious Diseases Society of America (IDSA), the Society for Healthcare Epidemiology of America (SHEA), the HIV Medicine Association (HIVMA) and the Pediatric Infectious Diseases Society (PIDS). IDWeek features the latest science and bench-to-bedside approaches in prevention, diagnosis, treatment and epidemiology of infectious diseases, including HIV, across the lifespan. IDWeek 2026™ takes place Oct. 21-24 at the Walter E. Washington Convention Center (801 Allen Y. Lew Place NW) in Washington, D.C. For more information, visit www.idweek.org.

Bixlenvo™, Yeztugo®, Biktarvy®, Gilead, and the Gilead logo are trademarks of Gilead Sciences, Inc., or its related companies. All other trademarks are the property of their respective owner(s).

Please see U.S. full Prescribing Information for Yeztugo, including BOXED WARNING, U.S. full Prescribing Information for Bixlenvo, and U.S. full Prescribing Information for Biktarvy, including BOXED WARNING, available at www.gilead.com.

For more information about Gilead, please visit the company’s website at www.gilead.com, follow Gilead on X (@Gilead_Sciences) and LinkedIn, or contact Gilead Public Affairs.

View source version on businesswire.com: https://www.businesswire.com/news/home/20261019303080/en/