BIIB vs GILD Stock Comparison: AI Score, Valuation, Performance and Upside
Both BIIB and GILD are large-cap biotechs with established specialty drug franchises facing varying degrees of competitive pressure and working to build next-generation growth drivers. Gilead has a more durable, highly cash-generative HIV franchise, while Biogen is navigating a more complex MS decline and Alzheimer's commercial uncertainty.
BIIB vs GILD compares two established large-cap biotechs — Biogen's neurology-focused franchise navigating MS decline and Alzheimer's opportunity, versus Gilead's stable HIV cash engine expanding into oncology.
BIIB holds the edge across 3 of 5 key metrics in this comparison. BIIB leads on both 1-year return (+70.40%) and forward P/E quality (13.21x vs 14.73x for GILD), a relatively favorable combination of momentum and valuation. GILD leads on both revenue growth (10.20%) and operating margin (33.68%), suggesting a stronger fundamental setup on both dimensions. Analyst consensus implies similar upside for both: +8.11% for BIIB and +8.05% for GILD.
Human Wall Street analysts' price targets, typically implying a ~12-month view — a separate signal from this site's own AI Prediction Signal further down the page, which is a 5-/30-day machine-learning forecast based on price history alone.
- See potential value in Biogen's Alzheimer's franchise if Leqembi adoption accelerates
- Believe the multiple sclerosis franchise provides adequate near-term cash generation
- Are comfortable with higher execution uncertainty in exchange for Alzheimer's disease upside potential
- Want exposure to a stable, large-cap biotech with a durable HIV cash cow
- Value Gilead's expanding oncology portfolio in breast cancer and CAR-T
- Prefer a more predictable, income-generating biotech with a meaningful dividend
| Metric | BIIB | GILD |
|---|---|---|
| AI scorei | 29.6 | 54.3 |
| AI ranki | #2322 | #507 |
| Latest closei | $254.46 | $174.48 |
| 1M returni | +13.81% | +20.64% |
| 3M returni | +23.15% | +32.42% |
| 6M returni | +33.45% | +28.01% |
| 1Y returni | +70.40% | +41.85% |
How much would $10,000 be worth today if invested at the start of each period, with all dividends reinvested?
| Period | BIIB | GILD |
|---|---|---|
| 1Y ago | $16.58K (+65.8%) started 2025-11-05 | $14.23K (+42.3%) started 2025-11-05 |
| 5Y ago | $9.33K (-6.7%) started 2021-11-08 | $35.27K (+252.7%) started 2021-11-08 |
| 10Y ago | $8.61K (-13.9%) started 2016-11-07 | $46.74K (+367.4%) started 2016-11-07 |
Hypothetical — past performance does not guarantee future results.
| Metric | BIIB | GILD |
|---|---|---|
| Market capi | $32.28B | $180.64B |
| Trailing P/Ei | 38.74 | 17.74 |
| Forward P/Ei | 13.21 | 14.73 |
| Price/Salesi | 1.99 | 4.87 |
| EV/Revenuei | 3.92 | 6.63 |
| Analyst targeti | $236.22 | $157.41 |
| Target upsidei | +8.11% | +8.05% |
| Metric | BIIB | GILD |
|---|---|---|
| Revenue growthi | 3.40% | 10.20% |
| Earnings growthi | -84.80% | 54.80% |
| EPS growthi | -84.80% | +54.80% |
| FCF margini | +12.63% | +32.07% |
| Operating margini | 25.06% | 33.68% |
| Profit margini | 8.32% | -10.64% |
| ROIC proxyi | 4.58% | -20.68% |
| Return on equityi | 4.58% | -20.68% |
| Dividend yieldi | N/A | 2.20% |
| Payout ratioi | 0.00% | 43.46% |
| Dividend growth streaki | N/A | No increase yet |
| Betai | 0.16 | 0.34 |
| Debt/equityi | 44.33 | 223.47 |
| Current ratioi | 1.86 | 1.26 |
| Quick ratioi | 0.94 | 0.90 |
Over the past year, BIIB and GILD have moved moderately in the same direction (correlation of 0.41), based on daily returns.
Lower drawdown and smaller single-period drops generally indicate a smoother ride, though they do not guarantee lower future risk.
| Period | Metric | BIIB | GILD |
|---|---|---|---|
| 1Y | Growthi | +65.85% | +42.34% |
| CAGRi | +65.97% | +42.41% | |
| Volatilityi | 34.19% | 27.64% | |
| Sharpe ratioi | 1.55 | 1.28 | |
| Sortino ratioi | 2.42 | 2.09 | |
| Max drawdowni | 14.34% | 22.03% | |
| Current drawdowni | 0.00% | 0.00% | |
| Avg drawdowni | 4.30% | 8.26% | |
| Ulcer Indexi | 5.47% | 10.36% | |
| Max daily dropi | 8.17% | 3.72% | |
| Max wkly dropi | 12.37% | 5.98% | |
| 5Y | Growthi | -6.69% | +204.13% |
| CAGRi | -1.38% | +24.96% | |
| Volatilityi | 34.79% | 25.08% | |
| Sharpe ratioi | -0.01 | 0.84 | |
| Sortino ratioi | -0.01 | 1.31 | |
| Max drawdowni | 64.35% | 26.59% | |
| Current drawdowni | 20.00% | 0.00% | |
| Avg drawdowni | 30.91% | 8.89% | |
| Ulcer Indexi | 35.34% | 10.94% | |
| Max daily dropi | 8.17% | 10.15% | |
| Max wkly dropi | 13.62% | 9.78% | |
| 10Y | Growthi | -13.92% | +223.18% |
| CAGRi | -1.49% | +12.45% | |
| Volatilityi | 41.40% | 25.72% | |
| Sharpe ratioi | 0.05 | 0.41 | |
| Sortino ratioi | 0.09 | 0.62 | |
| Max drawdowni | 72.66% | 30.47% | |
| Current drawdowni | 38.64% | 0.00% | |
| Avg drawdowni | 35.23% | 12.92% | |
| Ulcer Indexi | 39.50% | 14.94% | |
| Max daily dropi | 29.23% | 10.15% | |
| Max wkly dropi | 34.30% | 12.29% |
| Category | BIIB | GILD |
|---|---|---|
| Company | Biogen Inc. | Gilead Sciences, Inc. |
| Sector | Healthcare | Healthcare |
| Industry | Drug Manufacturers - General | Drug Manufacturers - General |
| Core business | Biogen is a large-cap biotechnology company focused on neurological diseases, including its established multiple sclerosis franchise (Tecfidera, Tysabri, Avonex) and its controversial Alzheimer's disease drugs (Aduhelm, Leqembi) developed in partnership with Eisai. | Gilead Sciences is a large-cap biotechnology company known for its dominant HIV antiretroviral franchise (Biktarvy, Descovy) and oncology portfolio (Trodelvy, Yescarta), with ongoing efforts to expand in viral hepatitis, inflammation, and other areas. |
| Investor focus | Investors track Leqembi adoption for Alzheimer's disease, Biogen's multiple sclerosis franchise durability against biosimilar and competitive pressure, and the overall pipeline strategy to offset declining MS revenues. | Investors track Biktarvy's HIV market leadership, Trodelvy's expansion in breast cancer and beyond, Yescarta's performance in CAR-T therapy, and Gilead's business development pipeline to supplement internal R&D. |
- Established leader in multiple sclerosis with a broad portfolio of FDA-approved therapies
- Leqembi (lecanemab) represents a potential franchise in Alzheimer's if it achieves meaningful commercial adoption
- Strong balance sheet and free cash flow provides flexibility for acquisitions and pipeline investment
- Biktarvy is the leading HIV treatment with a large, stable, recurring revenue base from patients on long-term therapy
- Oncology portfolio through Trodelvy (breast cancer) and Yescarta (CAR-T) provides diversification beyond HIV
- Strong cash flow from HIV franchise funds acquisitions and pipeline investment
- MS franchise faces biosimilar competition and revenue pressure as key drugs lose exclusivity
- Leqembi has seen slow initial commercial adoption due to complex administration, safety monitoring, and payer access issues
- Biogen has had a difficult period of strategic uncertainty following the controversial and then withdrawn Aduhelm Alzheimer's drug
- HIV franchise, while durable, faces eventual long-acting injectable competition and generics over time
- Oncology products Trodelvy and Yescarta are growing but still represent a smaller share of revenue than HIV
- Gilead has a mixed recent track record with its acquisitions relative to the prices paid
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