What CytomX Therapeutics does

CytomX Therapeutics is a clinical-stage biopharmaceutical company headquartered in South San Francisco, California, founded in 2010 and publicly traded on NASDAQ under the ticker CTMX. The company develops conditionally activated antibody therapeutics built on its proprietary Probody platform, in which a masking domain keeps an antibody inactive in healthy tissue and is cleaved by proteases enriched in the tumor microenvironment, enabling selective activation at the tumor site. The platform has been applied across multiple modalities, including antibody-drug conjugates (Varseta-M/CX-2051, an EpCAM-targeted ADC with a Topo-1 payload), T-cell engaging bispecifics (CX-908 targeting P-Cadherin x CD3), and cytokine therapeutics (CX-801, an interferon alpha-2b Probody). Lead clinical programs target metastatic colorectal cancer and advanced melanoma, with a registrational trial for Varseta-M planned for the first half of 2027.

CytomX operates a hybrid business model that combines a wholly-owned pipeline with a portfolio of strategic collaborations. Revenue is generated through licensing arrangements with major pharmaceutical partners — Regeneron, Bristol Myers Squibb, Amgen, and Moderna — comprising upfront payments, research funding, development and regulatory milestones, and tiered royalties on future net product sales, with over $400 million in committed payments from these partners as of early 2026. The company raised an additional $250 million via public offering in March 2026 to support pipeline development, bringing its cash position to approximately $346.7 million with runway projected into at least the second half of 2028. CytomX's marketed positioning emphasizes the Probody platform's ability to address historically "undruggable" tumor antigens by widening the therapeutic window, validated clinically by Phase 1 expansion data for Varseta-M showing a 32% confirmed response rate and 88% disease control rate in late-line metastatic colorectal cancer without EpCAM-class toxicities.

The company markets through scientific publications, presentations at major oncology congresses, and investor conferences, with clinical trials as the primary channel for advancing drug candidates. There are no commercially approved products, and all drug candidates are investigational; CytomX has between 101 and 250 employees, operates from a single South San Francisco headquarters, and is incorporated in Delaware, USA.

Name

CytomX Therapeutics

Legal name

CytomX Therapeutics, Inc.

Website

https://cytomx.com

Company type

Public

Founded year

2010

Operating status

Operating

Headcount range

101–250 employees

Short description

CytomX Therapeutics is a clinical-stage biopharmaceutical company developing conditionally activated antibody therapeutics on its Probody platform for solid tumors, with lead programs in metastatic colorectal cancer and melanoma. The company generates revenue through licensing and milestone payments from partnerships with Regeneron, Bristol Myers Squibb, Amgen, and Moderna.

Ownership category

akta.pro rank

Product category

Oncology Biopharmaceuticals

NAICS

Biological Product (except Diagnostic) Manufacturing (325414), Pharmaceutical Preparation Manufacturing (325412)

SIC

Pharmaceutical Preparations (2834), Biological Products, (No Disgnostic Substances) (2836)

akta.pro primary industry

Antibody Discovery & Engineering Platforms (display tech, bispecifics, Fc engineering) (HLAAAIAB)

akta.pro secondary industries

Antibody-Drug Conjugates (ADCs) & Antibody Conjugates (HLAAAAAE), Monoclonal Antibody Therapeutics (mAbs) (HLAAAAAA), Cytokines, Interferons & Immunomodulatory Proteins (HLAAAAAC)

Keywords

• Antibody therapeutics
• Oncology drug development
• Biopharmaceutical research
• Targeted cancer therapy
• Conditional antibody activation

Headquarters

HQ city

South San Francisco

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Operations, Supply Chain

Revenue model

1. Partnership/Collaboration Revenue: CytomX generates revenue through strategic partnerships with pharmaceutical companies including Regeneron, Bristol Myers Squibb, Amgen, and Moderna. Revenue includes upfront payments, research funding, preclinical/clinical milestone payments, regulatory milestones, and tiered royalties on net product sales. The company had over $400 million in committed payments from partners as of early 2026.
2. Public Stock Offering: CytomX raised $250 million in March 2026 through a public offering of common stock and pre-funded warrants to fund pipeline development, capital expenditures, and general corporate purposes.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

CytomX Therapeutics is a clinical-stage biopharmaceutical company developing conditionally activated antibody therapeutics (Probodies) for cancer treatment. Its pipeline includes lead candidate Varseta-M (CX-2051), an EpCAM-targeting antibody-drug conjugate for metastatic colorectal cancer, plus CX-801 (masked interferon alpha-2b cytokine) and CX-908 (a P-Cadherin x CD3 Probody T-cell engager). The company's core innovation is the Probody platform, which masks antibody activity until cleavage by tumor-associated proteases.

Product overview

CytomX Therapeutics is a clinical-stage biopharmaceutical company developing a portfolio of conditionally activated cancer therapeutics built on its proprietary PROBODY platform. The platform enables antibody-based therapies to remain masked in healthy tissue and activate specifically within tumor microenvironments. The core product portfolio includes Varseta-M (CX-2051), an EpCAM-directed ADC for metastatic colorectal cancer; CX-801, an interferon alpha-2b Probody cytokine for advanced melanoma; and CX-908, a P-Cadherin x CD3 T-cell engaging bispecific for solid tumors. These programs represent the company's wholly-owned pipeline, supplemented by strategic collaborations with partners including Regeneron, Amgen, Bristol Myers Squibb, and Moderna.

Differentiator

Problem solved

Functional benefit

Brands

• PROBODY: Proprietary therapeutic platform technology that engineers antibody therapeutics to remain masked until they encounter active proteases in the tumor microenvironment.

Products and services

• Varseta-M (CX-2051) An EpCAM-targeting antibody-drug conjugate built on the Probody platform, in clinical development for metastatic colorectal cancer and other EpCAM-expressing solid tumors. Designed to deliver a cytotoxic payload preferentially to tumor tissue via conditional antibody activation.
• CX-801 A masked (conditionally activated) interferon alpha-2b Probody cytokine designed to concentrate interferon activity within the tumor microenvironment while limiting systemic exposure and associated toxicity.
• CX-908 A Probody-format T-cell engager bispecific targeting P-Cadherin on tumor cells and CD3 on T cells, designed to engage T-cell cytotoxicity preferentially in tumor tissue and reduce systemic T-cell activation.
• Probody Therapeutic Platform CytomX's proprietary antibody engineering platform that generates conditionally activated biologics by incorporating a masking peptide linked via a protease-cleavable substrate, restricting activity to protease-rich environments such as tumors. The platform underpins both CytomX's internal pipeline and partner programs with Regeneron, Bristol-Myers Squibb, Amgen, and Moderna.

Quantifiable outcome

• 32% confirmed response rate at 10 mg/kg dose in late-line metastatic colorectal cancer patients
• +3 more outcomes

Named customers2 records

Segments1 record

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Five partnerships are on record, tiered secondary, core and minor.

• ModernasecondaryStrategic or Co-development Partner · 1 January 2023Strategic collaboration and licensing agreement to create investigational mRNA-based conditionally activated therapies for cancer and other diseases. CytomX received $35 million upfront including $5 million pre-paid research funding. Potential milestones up to approximately $1.2 billion plus tiered royalties on global net sales. Moderna leads clinical development and commercialization.
• Regeneron PharmaceuticalscoreStrategic or Co-development Partner · 3 March 2022Strategic collaboration to create conditionally-activated investigational bispecific cancer therapies combining CytomX's Probody platform with Regeneron's Veloci-Bi bispecific antibody platform. Initial agreement (2022) valued at up to $2 billion plus royalties. Expanded June 2026 with $37 million target selection payment for two additional programs, bringing total potential value to $4 billion with option for six more targets. CytomX receives upfront, milestone, and tiered global net sales royalty payments.
• Astellas PharmaminorStrategic or Co-development Partner · 1 March 2020Collaboration to co-develop Probody T-cell-engaging bispecific therapeutics targeting CD3 receptor and select oncology targets. Originally valued at up to $1.68 billion with $80 million upfront. Astellas terminated the partnership in Q2 2025 after choosing not to advance remaining preclinical programs, despite positive Phase 1 data for CytomX's Probody platform.
• AmgensecondaryStrategic or Co-development Partner · 1 January 2017Strategic immuno-oncology collaboration focused on research and development of T-cell-engaging bispecific therapeutics. Lead program CX-904 was discontinued in 2025 by mutual decision. Amgen has exclusive worldwide rights to develop up to three additional undisclosed targets, with CytomX eligible for upfront, milestone payments and high single-digit to mid-double digit royalties. CytomX also received rights to a preclinical T-cell engaging bispecific program.
• Bristol Myers SquibbcoreStrategic or Co-development Partner · 1 January 2014Research collaboration and license agreement to discover, develop and commercialize novel therapies against multiple targets using CytomX's Probody platform. Expanded in 2017 with $200 million upfront payment. Five oncology targets selected, with two remaining in preclinical development. CytomX eligible for future development, regulatory and sales milestone payments plus tiered royalties on net sales.

Scale indicators6 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Mersana Therapeutics: Clinical-stage ADC developer building a pipeline of conditionally activated and immune-stimulatory ADCs in oncology. Highly comparable to CytomX's Probody ADC approach in technology class, clinical-stage profile, and partnership-driven business model.
• ImmunoGen (acquired by AbbVie): Pioneer in antibody-drug conjugates for oncology, now part of AbbVie. Direct precedent for clinical-stage ADC platform companies achieving strategic exits, validating CytomX's ADC-centric pipeline strategy.
• Xencor: Clinical-stage biotech engineering monoclonal antibodies and bispecifics with XmAb platform technology. Comparable in platform-based engineering of antibody therapeutics and partnership-driven monetization.
• MacroGenics: Clinical-stage oncology biotech developing bispecific antibodies and ADCs. Comparable clinical-stage pipeline, oncology focus, and reliance on strategic pharma partnerships.
• Harpoon Therapeutics (acquired by Merck): Developed T-cell engaging bispecifics (TriTAC platform) for solid tumors, recently acquired by Merck. Comparable T-cell engager strategy and clinical-stage oncology focus, providing a recent exit benchmark for CytomX's bispecific work.

Emerging players

• ProfoundBio: Privately held, clinical-stage ADC developer focused on next-generation oncology therapeutics. Comparable emerging ADC player leveraging proprietary linker-payload technology with similar therapeutic ambitions.
• Compass Therapeutics: Clinical-stage bispecific antibody developer in oncology. Comparable small-cap clinical biotech with platform technology and partnership opportunities in bispecific antibody space.

Broad incumbents

• Regeneron Pharmaceuticals: Major biopharma developing Veloci-Bi bispecifics and antibody therapeutics; also a CytomX collaboration partner. Comparable as a broad incumbent in bispecific antibody development that validates CytomX's target space.
• Amgen: Pioneer of BiTE T-cell engager platform and active ADC developer; also a CytomX partner. Comparable as a large incumbent whose platform choices (and recent CX-904 discontinuation) directly influence CytomX's competitive context.
• Bristol Myers Squibb: Global biopharma with established immunotherapy, ADC, and bispecific franchises; longstanding CytomX collaboration partner since 2014. Relevant as both strategic partner and broader benchmark for the oncology platform partnering model.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat3 records

Key risks4 records

Key highlights6 records

Customer concentration

• Xx.com/cytomxinc
• LinkedInlinkedin.com/company/cytomx-therapeutics

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds10 records

Investors19 records

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M&A1 record

Investments

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

Frequently asked questions about CytomX Therapeutics