What Changed
Price Move History
- Daily moves over 5%
- 8 252 sessions, November 4, 2025 to November 4, 2026
- Largest daily move
- +8.5% close of February 6, 2026
- 1-year change
- +70.4% closing prices, November 4, 2025 to November 4, 2026
- 1-month change
- +15.7% closing prices, October 2, 2026 to November 4, 2026
Company Description
Biogen Inc. (NASDAQ: BIIB) is a biotechnology company in the biological product manufacturing industry, with a long-standing focus on serious neurological and rare diseases. According to company disclosures, Biogen was founded in 1978 and concentrates on applying a deep understanding of human biology and multiple therapeutic modalities to develop medicines that aim to transform patients’ lives while creating value for shareholders and communities.
Core therapeutic focus and scientific approach
Biogen describes itself as a biotechnology company that "pioneers innovative science" to deliver new medicines. Its strategy emphasizes advancing first-in-class treatments or therapies that deliver superior outcomes, taking what it calls bold but return-conscious risks to support long-term growth. The company highlights a particular commitment to neurological and neuromuscular conditions, as reflected in its marketed and investigational therapies for spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), and Alzheimer’s disease, as well as collaborations in developmental epileptic encephalopathies such as Dravet syndrome.
Key marketed and partnered therapies
Biogen’s portfolio and collaborations, as described in recent press releases, include:
- SPINRAZA (nusinersen) – An antisense oligonucleotide licensed from Ionis Pharmaceuticals for the treatment of 5q spinal muscular atrophy, the most common form of SMA. SPINRAZA has been approved in the European Union since 2017 and is indicated for infants, children and adults with SMA. A high-dose regimen (50 mg/5 mL and 28 mg/5 mL) has received marketing authorization in the European Union and Japan, with the regimen under review by the U.S. Food and Drug Administration. Biogen reports that SPINRAZA has treated more than 10,000 infants, children, teens and adults worldwide.
- QALSODY (tofersen) – An antisense oligonucleotide licensed from Ionis Pharmaceuticals for SOD1 amyotrophic lateral sclerosis (SOD1-ALS). QALSODY 100 mg/15 mL injection is approved for adults with ALS who have a mutation in the SOD1 gene. In the United States, it received accelerated approval based on reduction in plasma neurofilament light chain, with continued approval potentially contingent on verification of clinical benefit in confirmatory trials. Biogen reports approvals in multiple countries and ongoing evaluation in the Phase 3 ATLAS study in presymptomatic individuals with SOD1 mutations.
- LEQEMBI (lecanemab-irmb) – An anti-amyloid beta monoclonal antibody for early Alzheimer’s disease, developed and co-commercialized with Eisai. LEQEMBI targets aggregated soluble protofibrils and insoluble amyloid-beta plaques. It is indicated for patients with mild cognitive impairment or mild dementia stage of Alzheimer’s disease. LEQEMBI has been approved in numerous countries and is available as an intravenous infusion and as subcutaneous formulations, including LEQEMBI IQLIK for weekly maintenance dosing and a subcutaneous autoinjector under regulatory review for initiation dosing.
Pipeline and collaboration strategy
Biogen’s disclosures emphasize a broad pipeline and collaboration model. The company works with partners such as Ionis Pharmaceuticals, Eisai, Stoke Therapeutics, and Dayra Therapeutics to access different technologies and therapeutic areas.
- With Stoke Therapeutics, Biogen is collaborating on zorevunersen, an investigational antisense oligonucleotide designed to treat the underlying cause of Dravet syndrome by increasing functional NaV1.1 protein production from the non-mutated SCN1A allele. Under this collaboration, Stoke retains exclusive rights in the United States, Canada and Mexico, while Biogen holds exclusive commercialization rights in the rest of the world.
- Biogen also reports a robust discovery pipeline in ALS, including efforts targeting TDP43 pathology, which it notes is seen in a large proportion of ALS cases and is considered a hallmark of the disease.
- In immunology, Biogen has entered a research collaboration with Dayra Therapeutics to discover and develop oral macrocyclic peptides for priority immunological targets. Biogen states that macrocyclic peptides may offer biologic-like efficacy and safety in an oral format and can address protein binding sites that are challenging for traditional small molecules.
- Biogen is also advancing BIIB080, an investigational antisense oligonucleotide targeting microtubule-associated protein tau (MAPT) mRNA to reduce tau protein production. Abnormal tau accumulation is described as a hallmark of Alzheimer’s disease, and BIIB080 is being evaluated in a Phase 2 study in early Alzheimer’s disease.
Therapeutic areas and modalities
Across its communications, Biogen highlights several recurring themes:
- Neurology and neurodegeneration: Focus on ALS (including SOD1-ALS), Alzheimer’s disease, SMA, and other neurological conditions.
- Genetic and rare diseases: Use of antisense oligonucleotides and other modalities to address genetically defined subtypes such as SOD1-ALS, 5q SMA, and Dravet syndrome with SCN1A variants.
- Multiple modalities: Use of monoclonal antibodies (e.g., lecanemab), antisense oligonucleotides (e.g., nusinersen, tofersen, BIIB080, zorevunersen collaborations), and emerging modalities such as oral macrocyclic peptides.
Regulatory and clinical development activities
Biogen’s recent news flow underscores active engagement with global regulators and clinical research networks. Examples include:
- European Commission approval of a high-dose SPINRAZA regimen for 5q SMA, supported by the Phase 2/3 DEVOTE study and its extension, and additional approvals in Japan.
- Publication of long-term QALSODY Phase 3 VALOR and open-label extension data in JAMA Neurology, reporting associations between early initiation and slower decline in clinical function, breathing and strength, as well as reductions in neurofilament.
- Multiple presentations at the Clinical Trials on Alzheimer’s Disease (CTAD) Conference on LEQEMBI, including analyses of long-term treatment effects, subcutaneous administration, and pharmacodynamic data on amyloid-beta protofibrils in cerebrospinal fluid.
- Ongoing global Phase 3 programs and open-label extension studies for zorevunersen in Dravet syndrome, conducted by Stoke Therapeutics with Biogen as strategic collaborator and rest-of-world commercialization partner.
Financial reporting and public company status
Biogen is a publicly traded company with its common stock listed on The Nasdaq Global Select Market under the symbol BIIB, as confirmed in recent Form 8-K filings. These filings show that Biogen regularly reports quarterly results and provides updates on acquired in-process research and development, upfront and milestone expenses related to collaboration and license agreements. The company has also reported on shareholder matters such as the election of directors and ratification of its independent registered public accounting firm.
Corporate governance and shareholder communications
Biogen’s filings and press releases indicate that it routinely communicates with investors through SEC filings, press releases and other channels. The company notes that it posts information that may be important to investors on its corporate website and uses social media platforms such as Facebook, LinkedIn, X and YouTube as additional communication channels.
Position within the biotechnology sector
Within the broader manufacturing sector and the biological product manufacturing industry, Biogen positions itself as a biotechnology company centered on serious neurological and rare diseases, with a portfolio that spans marketed therapies, late-stage assets, and early discovery collaborations. Its emphasis on antisense oligonucleotides, monoclonal antibodies, and emerging modalities such as macrocyclic peptides reflects a strategy of combining different scientific approaches to address complex diseases of the nervous system and immune system.
Stock Performance
Biogen (BIIB) closed at $254.46 on November 4, 2026. Over the past 12 months, the price has gained 70.4%.
BIIB Metrics & Rankings
Price returns through November 4, 2026. Month and year figures include the first trading day. Ranking links may use different dates.
Latest News
Biogen has 10 recent news articles, with the latest published 2 days ago. Of the recent coverage, 5 articles coincided with positive price movement and 5 with negative movement. Key topics include conferences, earnings, clinical trial, management. View all BIIB news →
SEC Filings
Biogen has filed 10 recent SEC filings, including 4 Form 4, 2 Form 144, 1 Form 3, 1 Form 10-Q. The most recent filing was submitted on . SEC filings provide transparency into a company's financial condition, material events, and regulatory compliance. View all BIIB SEC filings →
Financial Highlights
Biogen generated $9.9B in revenue in FY2025, retaining a 75.7% gross margin, and net income was $1.3B, reflecting a 13.1% net profit margin. Diluted earnings per share stood at $8.79. The company generated $2.2B in operating cash flow. The current ratio was 2.68, measuring current assets divided by current liabilities.
Upcoming Events
CTAD conference presentations
Diranersen symposium
Lecanemab presentations
AMETHYST Phase 3 readout
Rolling NDA initiation
TRANSCEND data readout
Phase 3 results
Phase 3 data readout window
Rolling U.S. NDA start
Phase 3 EMPEROR readout
Phase 3 data readout
U.S. NDA completion
New global headquarters opening
Potential FDA approval
SPINRAZA device launch
Product launch
PROMINENT trial results
Biogen has 19 upcoming scheduled events. The next event, "CTAD conference presentations", is scheduled for November 16, 2026 (in 11 days). Investors can track these dates to stay informed about potential catalysts that may affect the BIIB stock price.
Short Interest History
Short interest in Biogen (BIIB) currently stands at 5.5 million shares, down 7.8% from the previous reporting period, representing 3.7% of the float. Since November 2025, short interest has decreased by 10.4%.
Days to Cover History
Days to cover for Biogen (BIIB) currently stands at 4.4 days, down 9.9% from the previous period. The ratio is the reported short interest divided by the average daily trading volume. Since November 2025, the figure has increased by 37.6%. Across the settlements charted above, it has ranged from 1.7 to 8.7 days.
BIIB Company Profile & Sector Positioning
Biogen (BIIB) operates in the Drug Manufacturers - General industry within the broader Healthcare sector and is listed on the NASDAQ.
Investors comparing BIIB often look at related companies in the same sector, including GSK plc (GSK), Bristol-Myers Squibb Co. (BMY), Sanofi (SNY), Pfizer Inc. (PFE), and Novo Nordisk A/S (NVO). Comparing financial metrics, valuation ratios, and stock performance across these peers can help investors evaluate BIIB's relative position within its industry.