Biogen Inc. (BIIB) Stock

Biogen Inc. (BIIB) is a Healthcare stock trading at $216.28 (as of 2026-09-15), with a market capitalization of $32.16B and a trailing P/E of 38.5. Figures are sourced from first-party U.S. SEC EDGAR filings and market data.

Biogen Inc. develops, manufactures, and commercializes therapies for neurological and other diseases, including treatments for multiple sclerosis, spinal muscular atrophy, and Alzheimer’s disease, along with medicines for conditions such as plaque psoriasis and certain cancers and autoimmune disorders. Its portfolio includes products and biosimilar medicines, with sales primarily in the U.S. and international markets.

Understand Biogen Inc.: how it makes money

Biogen discovers and sells branded therapies for neurological diseases (multiple sclerosis, spinal muscular atrophy, Alzheimer's, complement disorders) and biosimilars to patients through pharmacies and hospitals. MS products and SPINRAZA still anchor the top line, but anti-CD20 immunology and LEQEMBI are shifting the revenue mix away from a single-disease franchise.

Biogen's profit engine is a rolling patent-replacement cycle: each franchise matures on a timer, so 73% gross margins depend on continuously converting late-stage pipeline into new branded launches before the prior generation erodes.

Revenue by segment (latest quarter)
MS Products$1.0B
RITUXAN$0.5B
SPINRAZA$0.4B
Biosimilars$0.2B
LEQEMBI$0.2B
SKYCLARYS$0.1B
Other$0.2B

Business quality (Mixed): Excellent gross margins and a broad neurology portfolio, but only 2% top-line growth, a 2026 EPS dilution hit from Apellis financing, and a 37% valuation premium to peers make this a 'good but not compounding' story at current multiples.

Valuation: At 23× earnings, BIIB trades 37% above the Pharmaceutical Products average (17×).

Bull case

  • Pipeline spans four indications: Management flagged late-stage readouts in lupus, antimicrobial resistance, and Dravet syndrome as additional growth catalysts beyond the current portfolio. Multiple Phase 3 programs across distinct disease areas reduce the risk that a single approval miss stalls the revenue ramp.
  • Apellis synergy stream to 2027: Biogen expects the Apellis acquisition to generate $250 million of run-rate synergies by 2027, which would help fund the $6.8 billion debt load and restore operating leverage once integration costs subside.

Bear case

  • $6.8B net debt overhang: The balance sheet ended the quarter with $6.8 billion of net debt, and the Apellis financing already carries 2026 EPS dilution. Until synergies ramp, leveraged interest costs compress the bottom line during a year when top-line growth is only 2%.
  • P/E trades 37% above peers: At 23.5 times earnings versus a 17 times industry average, Biogen commands a 37% premium that is hard to justify while quarterly revenue grows just 2% year over year. The multiple assumes pipeline convertibility that has yet to be proven in reported sales.
  • MS franchise losing momentum: Biogen paused development of its BTK inhibitor amid intensifying MS competition, removing a key next-generation lever for a segment that still represents roughly 38% of total revenue. Without a new MS differentiator, the core franchise faces gradual share erosion.
Valuation — source: SEC EDGAR (first-party)
Price$216.28
Market Cap$32.16B
P/E Ratio38.5
EV / EBITDA11.7
Price / Book1.71
Price / Sales3.21
FCF Yield8.4%
DCF Value (model)$262.53
DCF Upside vs Price21.4%
Profitability & Growth — source: SEC EDGAR
Revenue (TTM)$9.89B
Net Margin13.1%
Return on Equity4.4%
Debt / Equity0.39
Current Ratio1.87
Revenue Growth (YoY)3.4%
EPS Growth (YoY)-84.8%
FCF Growth (YoY)203.8%
Financial Health — source: SEC EDGAR
Piotroski F-Score5/9 (moderate)
Valuation vs Sector & Industry
Stock P/E38.5
Sector P/E (Healthcare)20.7
Industry P/E (Pharmaceutical Products)15.0
vs Sector85.9%
vs Industry157.0%
Smart-Money Activity — SEC Form 4 / 13F / Congressional disclosures
Top Institutional HolderFMR LLC ($3.94B)
Institutional Holders Tracked10
Congressional Trades (recent)10
Company
SectorHealthcare
IndustryPharmaceutical Products
CEOChristopher A. Viehbacher
Employees7,605
CountryUS
IPO Date1991-09-17

Biogen Inc. earnings call transcripts

  • BIIB Q2 FY26 earnings call transcript (reported 2026-07-29) · analysis
  • BIIB Q1 FY26 earnings call transcript (reported 2026-04-29) · analysis
  • BIIB Q3 FY25 earnings call transcript (reported 2025-10-30) · analysis

All BIIB earnings calls

Related Companies (Pharmaceutical Products; 8 comparable drugmakers)

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  • Novavax, Inc. (NVAX)
  • Moderna, Inc. (MRNA)
  • Vertex Pharmaceuticals Incorporated (VRTX)
  • REGENXBIO Inc. (RGNX)
BIIB earnings history · BIIB institutional & insider holders · BIIB KPIs & operating metrics · BIIB financials · BIIB filings, presentations & press releases · BIIB investor presentations & press releases · BIIB SEC filings · BIIB peers · Congress trades · Insider trades · Short interest · Stock screener

Data as of 2026-09-15.

Figures sourced from U.S. Securities and Exchange Commission (SEC EDGAR) filings and market data. Not personalized investment advice.