Annexon Biosciences

Name

Annexon Biosciences

Legal name

Annexon, Inc.

Website

https://annexonbio.com

Company type

Public

Founded year

2015

Operating status

Operating

Headcount range

101–250 employees

Ownership category

akta.pro rank

Product category

Complement Therapeutics Biopharmaceuticals

akta.pro primary industry

Immunology & Autoimmune Specialty Pharmaceuticals (HLAIACAB)

akta.pro secondary industry

Rare Immunology, Autoimmune & Autoinflammatory Therapies (HLAIAIAE)

Keywords

• Complement therapeutics
• Classical complement pathway
• C1q inhibition
• Neurodegenerative disease drugs
• Autoimmune disease therapeutics

Headquarters

HQ city

South San Francisco

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Product Revenue: Pre-revenue clinical-stage biopharmaceutical company. No approved products yet. Revenue expected upon regulatory approval and commercialization of tanruprubart, vonaprument, and other pipeline candidates.

Go-to-market motion1 record

Marketing channels3 records

Core offering

Annexon Biosciences is a clinical-stage biopharmaceutical company developing therapeutics that inhibit C1q, the initiating molecule of the classical complement pathway, to treat autoimmune, neurodegenerative, and ophthalmic diseases. Its pipeline includes the IV monoclonal antibody Tanruprubart (ANX005) for Guillain-Barré Syndrome, the intravitreal Fab Vonaprument (ANX007) for geographic atrophy, the oral small molecule ANX1502 for complement-mediated autoimmune diseases, and the subcutaneous Fab ANX009 for antibody-mediated autoimmune diseases such as lupus nephritis.

Differentiator

Problem solved

Functional benefit

Brands

• Tanruprubart (ANX005): Clinical-stage investigational monoclonal antibody for intravenous administration designed to inhibit C1q and the entire classical complement pathway for treatment of Guillain-Barré Syndrome (GBS).
• Vonaprument (ANX007)
• ANX1502
• ANX009

Products and services

• Tanruprubart (ANX005) Tanruprubart is a clinical-stage investigational monoclonal antibody (mAb) designed for intravenous administration that inhibits C1q and the entire classical complement pathway. It is being developed for the treatment of Guillain-Barré Syndrome (GBS), a severe acute neuromuscular disease caused by autoantibody attack on peripheral nerves. It has received FDA Fast Track and Orphan Drug designations and EMA Orphan Drug Designation.
• Vonaprument (ANX007) Vonaprument is a clinical-stage investigational monoclonal antibody antigen-binding fragment (Fab) formulated for intravitreal (IVT) administration, targeting C1q and the entire classical pathway while preserving normal immune activity of the lectin and alternative complement pathways. It is being developed for geographic atrophy (GA), an advanced form of dry age-related macular degeneration. It has received FDA Fast Track and EMA PRIME designations.
• ANX1502 ANX1502 is a first-in-class oral small molecule inhibitor of the classical complement pathway being developed for complement-mediated autoimmune diseases, including cold agglutinin disease. The oral route differentiates it from the company's antibody-based programs and supports chronic dosing in autoimmune indications.
• ANX009 ANX009 is a subcutaneously administered antigen-binding fragment (Fab) being developed for antibody-mediated autoimmune diseases of blood and vascular tissues, including lupus nephritis, a severe nephritic disease characterized by autoantibody-driven C1q activation.

Quantifiable outcome

• ARCHER II Phase 3 trial enrollment completed; Ph3 data expected 2H26 for vonaprument in geographic atrophy
• +1 more outcomes

Segments6 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

One partnership is on record.

• MindWalk Holdings Corp.coreTechnology or Integration · 18 May 2026MindWalk Holdings Corp. released a systematic report documenting over 20 discovery-originated drug candidates their antibody discovery work produced for partners. Annexon Biosciences is listed among partner companies advancing clinical-stage programs originated through MindWalk's discovery work. MindWalk's proprietary wet-lab antibody discovery platform and HYFT biological intelligence infrastructure support Annexon's clinical programs.

Scale indicators8 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• Apellis Pharmaceuticals: Apellis is the most direct competitor with Syfovre (pegcetacoplan), the first FDA-approved C3 inhibitor for geographic atrophy, and Empaveli for PNH. Both companies target complement-mediated diseases with ocular and systemic programs in late-stage development.
• Iveric Bio (Astellas): Iveric developed Izervay (avacincaptad pegol), a C5 inhibitor approved for geographic atrophy and acquired by Astellas in 2023. It is a direct competitor to vonaprument in the same indication, shaping market dynamics for any Annexon GA launch.
• argenx: argenx developed Vyvgart (efgartigimod), an FcRn antibody approved for generalized myasthenia gravis and expanding into CIDP and other autoimmune indications. Both companies are clinical/commercial-stage antibody developers focused on antibody-mediated autoimmune diseases.

Broad incumbents

• Alexion / AstraZeneca Rare Disease: Alexion pioneered complement therapeutics with Soliris and Ultomiris (C5 inhibitors) for PNH, aHUS, gMG, and NMOSD, and has commercial reach and a deep autoimmune/neurology pipeline. Annexon's C1q approach competes against Alexion's installed base in complement-mediated indications.
• Regeneron: Regeneron is a major antibody platform company with Eylea HD for retinal disease and a deep immunology pipeline including linvoseltamab and odronextamab. It represents an incumbent competitive threat across Annexon's ophthalmology and autoimmune programs.
• Genentech / Roche: Roche/Genentech markets Ocrevus for MS and has a broad immunology and ophthalmology franchise. Annexon's MS/ALS/Huntington's programs and lupus nephritis indications compete against Roche's established autoimmune commercial footprint.
• BioMarin Pharmaceutical: BioMarin is a commercial-stage rare disease biotech with multiple specialty therapeutics. Annexon's GBS, ALS, and Huntington's programs target rare neurological diseases where BioMarin's commercial and regulatory experience sets a comparable benchmark.
• Takeda Pharmaceutical: Through its Shire acquisition, Takeda has a large rare disease and neuroscience franchise including Takhzyro (HAE) and Adynovate. Annexon's complement-mediated neuro programs compete for similar specialty neurology patients and physician networks.

Emerging players

• Alnylam Pharmaceuticals: Alnylam develops RNAi therapeutics for rare diseases including Onpattro, Givlaari, and Oxlumo. Both companies target rare genetic and complement-mediated diseases with novel modality platforms advancing through similar commercial inflection points.
• Cabaletta Bio: Cabaletta is a clinical-stage biotech developing CAAR T-cell therapies for autoimmune diseases including lupus nephritis and myositis. They overlap with Annexon's autoimmune disease focus, particularly in lupus nephritis where ANX009 is in development.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/annexonbio

Revenue estimate

Valuation estimate

Number of profiles

Profiles11 records

Funding overview

Funding rounds10 records

Investors21 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Annexon Biosciences