Gilead Sciences: HIV Dominance, Oncology Expansion, and Biotech Franchise Value

Gilead Sciences headquarters in Foster City, California. The company built a dominant HIV franchise and expanded into oncology, liver disease, and cell therapy.

Gilead Sciences Inc. (NASDAQ: GILD) is a biopharmaceutical company headquartered in Foster City, California, with approximately $29.4 billion in total revenue (FY2025). Founded in 1987, Gilead transformed the treatment of HIV and hepatitis C with breakthrough antiviral therapies and has since expanded into oncology (cell therapy), inflammation, and liver disease.

This article explains Gilead's business model, revenue sources, pipeline strategy, and key risks in plain English — without offering investment advice.

What Gilead Sciences Actually Does

Gilead discovers, develops, and commercializes medicines primarily in virology, oncology, and inflammation. The company operates as a single reportable segment but organizes its portfolio around therapeutic areas:

• HIV/AIDS — the dominant franchise, providing ~72% of product revenue through best-in-class antiretroviral therapies
• Oncology — CAR-T cell therapy (Yescarta, Tecartus) and antibody-drug conjugate Trodelvy for solid tumors
• Liver diseases — hepatitis B treatments (Vemlidy), Livdelzi for primary biliary cholangitis, and legacy hepatitis C cures
• Inflammation — filgotinib (Jyseleca) in select markets
• COVID-19 — Veklury (remdesivir), now a rapidly declining contributor

Gilead sells globally, with the United States representing approximately 70% of product revenue.

Revenue Structure (FY2025)

Key FY2025 metrics (calendar year ending December 2025, from the 10-K filed with SEC):

• Total revenue: ~$29.4 billion
• Total product sales: $28.9 billion (up 1% YoY; up ~5% excluding Part D redesign headwind)
• HIV franchise revenue: $20.8 billion (up 6% YoY; ~72% of product sales)
• Biktarvy: $14.3 billion (up 7%)
• Descovy: $2.8 billion (up 31%, driven by PrEP demand)
• Yeztugo (lenacapavir PrEP): $150 million (launch year)
• Liver disease: $3.2 billion (up 6%, Livdelzi driving growth)
• Trodelvy (oncology ADC): $1.4 billion (up 6%)
• Cell therapy (Kite): $1.8 billion (down 7%, competitive pressures)
• Veklury (COVID-19): $911 million (down 49%)
• Non-GAAP product gross margin: 86.4%
• Non-GAAP operating margin: 45% (48% excluding IPR&D and nonrecurring items)
• R&D expenses: $5.7 billion
• Non-GAAP diluted EPS: $8.15
• Net income (GAAP): $8.5 billion
• Shareholder returns: $5.9 billion (63% of free cash flow)

The HIV Franchise — Gilead's Core Engine

HIV is Gilead's defining franchise and the source of its cash flow dominance:

• Biktarvy (bictegravir/emtricitabine/TAF) — the #1 prescribed HIV treatment globally. Revenue $14.3 billion in FY2025 (up 7%). U.S. market share exceeds 52% with year-over-year gains every quarter since launch.
• Descovy (emtricitabine/TAF) — used for HIV treatment and pre-exposure prophylaxis (PrEP). Revenue $2.8 billion (up 31%). U.S. PrEP market share exceeds 45%.
• Yeztugo (lenacapavir, branded YES2GO) — first-in-class capsid inhibitor approved for twice-yearly HIV prevention (PrEP). Launched in 2025 with $150 million in first-year sales. Achieved 90% payer coverage ahead of target. Guided for ~$800 million in 2026.
• Odefsey, Genvoya, and other TAF-based regimens — legacy products still generating revenue but declining as patients switch to Biktarvy.

Gilead's HIV moat rests on decades of clinical data, physician trust, high switching costs (patients stable on therapy rarely switch), and a pipeline of long-acting formulations that extend franchise life. No major loss of exclusivity (LOE) until 2036.

Oncology: Cell Therapy and Trodelvy

Gilead's oncology portfolio spans CAR-T cell therapy (via Kite Pharma, acquired 2017) and antibody-drug conjugates (via Immunomedics, acquired 2020):

• Yescarta (axicabtagene ciloleucel) — CAR-T therapy for large B-cell lymphoma. Part of the $1.8 billion cell therapy franchise.
• Tecartus (brexucabtagene autoleucel) — CAR-T for mantle cell lymphoma and ALL.
• Trodelvy (sacituzumab govitecan) — antibody-drug conjugate for metastatic triple-negative breast cancer. Revenue $1.4 billion (up 6%). Now recommended by NCCN for both first- and second-line metastatic TNBC regardless of PD-L1 status.
• Anidocel — investigational BCMA-targeting CAR-T for multiple myeloma. Filed with FDA; potential launch in second half of 2026.
• Cell therapy challenges: competitive pressures from bispecific antibodies; revenue declined 7% in FY2025 with further ~10% decline expected in 2026.

Liver Disease Portfolio

• Liver disease total: $3.2 billion (up 6% in FY2025)
• Livdelzi (seladelpar) — for primary biliary cholangitis (PBC). Rapid adoption following competitor withdrawal; now U.S. market share leader with >50% in second-line PBC.
• Vemlidy (TAF for hepatitis B) — chronic HBV treatment. Steady contributor.
• Legacy HCV cures (Harvoni, Sovaldi, Epclusa) — revenue continues to decline as the treatable patient pool shrinks.
• HCV taught Gilead a key lesson: curative therapies generate enormous short-term revenue but are self-limiting. This informed the pivot to chronic-treatment franchises.

Pipeline and R&D

Gilead has up to 10 ongoing and potential new launches through 2027, with 53 clinical programs and five FDA decisions expected in 2026:

• Yeztugo (lenacapavir PrEP) — approved and launched in 2025. Guided for $800 million in 2026 revenue. Once-yearly PrEP formulation (PURPOSE 365 trial) could be available as early as 2028.
• Viclen (bictegravir + lenacapavir) — once-daily oral HIV treatment combination. Positive Phase 3 results (ARTISTRY I and II). Potential launch second half 2026.
• Islatrovir + lenacapavir — potential first once-weekly oral HIV treatment. Phase 3 updates expected 2026.
• Lenacapavir + broadly neutralizing antibodies — twice-yearly HIV treatment. Phase 3 trial initiating 2026.
• Trodelvy expansions — first-line metastatic TNBC (FDA decision 2026), endometrial cancer, non-small cell lung cancer trials ongoing.
• Anidocel (BCMA CAR-T) — 96% overall response rate in Phase 2. FDA decision expected 2026 for fourth-line multiple myeloma.
• Bruleviratide — for chronic hepatitis D. FDA decision expected 2026.
• R&D spend: $5.7 billion in FY2025 (~19% of revenue)

Capital Allocation

• Shareholder returns: $5.9 billion in FY2025 (63% of free cash flow), including $1.9 billion in share repurchases plus dividends.
• Dividend — consistent payer with moderate growth. Yield ~3.3%.
• M&A history — Pharmasset ($11B, 2012), Kite ($12B, 2017), Immunomedics ($21B, 2020). ~$1 billion annually in early-stage partnerships and collaborations.
• Debt management — investment-grade rated. Manageable leverage.
• 2026 guidance — total product sales $29.6–$30.0 billion; non-GAAP EPS $8.45–$8.85.

Key Risks

• HIV franchise concentration — ~72% of product sales from HIV. Any disruption (generic competition, new entrant, pricing pressure) would be material.
• Policy and pricing headwinds — Medicare Part D redesign cost ~$900 million in 2025; drug pricing agreement and ACA changes expected to create ~2% growth headwind in 2026.
• Cell therapy competitive pressure — revenue declining as bispecific antibodies gain share. Expected ~10% decline in 2026.
• Trodelvy competition — ADC space is increasingly crowded with competitors from Daiichi Sankyo/AstraZeneca and others.
• Veklury decline — COVID-19 revenue fell 49% in FY2025 to $911 million; further decline expected.
• Pipeline execution risk — multiple FDA decisions and Phase 3 readouts in 2026 create binary event risk.
• Manufacturing complexity — CAR-T requires patient-specific manufacturing; lenacapavir long-acting formulation requires specialized production.
• M&A integration — large acquisitions carry execution risk.

Investor-Education Context

• HIV cash machine — Gilead's HIV franchise generates enormous, predictable cash flows from a chronic-treatment market with high switching costs and physician loyalty. No major LOE until 2036.
• Yeztugo is the key near-term catalyst — twice-yearly PrEP launched successfully in 2025 and is guided for $800 million in 2026, with potential for once-yearly formulation by 2028.
• Diversification accelerating — up to 10 launches through 2027 across HIV, oncology, and liver disease, reducing historical single-franchise dependence.
• Acquisition-driven growth model — Gilead has repeatedly used M&A to enter new therapeutic areas. ~$1 billion annually in early-stage deals plus disciplined larger transactions.
• Capital return profile — $5.9 billion returned in FY2025 (63% of FCF). Committed to returning at least 50% of free cash flow to shareholders.

This article is educational. It does not constitute investment advice, a recommendation to buy or sell, or a valuation opinion.

Sources

• Gilead Sciences Inc. 10-K FY2025 (SEC EDGAR, accession 0000882095-26-000006)
• Gilead Sciences Q4 FY2025 Earnings Release and Call Transcript (February 10, 2026)
• Gilead Sciences Pipeline page (gilead.com/science-and-medicine/pipeline)
• FDA approval records for Biktarvy, Yeztugo (lenacapavir/Sunlenca), Yescarta, Trodelvy
• Gilead investor presentations and 2026 guidance
• PURPOSE 1 clinical trial results (ClinicalTrials.gov NCT04994509)