ITeos Therapeutics
iTeos Therapeutics is a clinical-stage immuno-oncology biotech developing anti-TIGIT antibodies, notably belrestotug with GSK, and is now being acquired by Concentra Biosciences following its lead candidate's Phase II failure.
- Company typePrivate
- Founded2011
- HeadquartersCambridge, United States
- Headcount101–250
- GTM typeB2B
- OfferingHardware or Manufacturing
What ITeos Therapeutics does
iTeos Therapeutics was a clinical-stage biotechnology company specializing in tumor immunology and immuno-oncology drug discovery, founded in 2011 and headquartered in the Cambridge/Watertown, Massachusetts area. The company's scientific focus was on developing anti-TIGIT antibodies and other candidates designed to modulate the tumor microenvironment and enhance anti-tumor immune responses. Its lead asset was belrestotug, an anti-TIGIT antibody being co-developed with GSK until May 2025, alongside an earlier-stage pipeline targeting complementary immune checkpoint and tumor microenvironment mechanisms. The company had no approved products and no product revenue throughout its operating history.
iTeos's business model was that of a traditional clinical-stage biotech: it did not sell commercial products, did not operate recurring software or services revenue, and instead funded operations through successive private and public equity rounds (including a 2020 IPO under the ticker ITOS on NASDAQ) and through collaboration income from pharmaceutical partners, principally GSK. Pricing and commercialization infrastructure were not applicable because no candidate reached approval.
In 2025, iTeos entered a sharp negative trajectory: belrestotug failed in Phase II, GSK terminated the partnership in May 2025, and the company entered a definitive merger agreement on July 21, 2025 to be acquired by Concentra Biosciences for approximately $10.047 per share in cash plus a contingent value right, with closing anticipated in Q3 2025. The acquisition effectively ends iTeos as an independent operating company and removes any standalone expansion path for the remaining pipeline.
ITeos Therapeutics firmographics
Firmographics- Name
- ITeos Therapeutics
- Legal name
- iTeos Therapeutics
- Website
- https://iteostherapeutics.com
- Company type
- Private
- Founded year
- 2011
- Operating status
- Acquired
- Headcount range
- 101–250 employees
- Short description
- iTeos Therapeutics is a clinical-stage immuno-oncology biotech developing anti-TIGIT antibodies, notably belrestotug with GSK, and is now being acquired by Concentra Biosciences following its lead candidate's Phase II failure.
- Ownership category
- akta.pro rank
ITeos Therapeutics industry classification
Industry- Product category
- Immuno-oncology Therapeutics
- NAICS
- Research and Development in Biotechnology (except Nanobiotechnology) (541714), Biological Product (except Diagnostic) Manufacturing (325414)
- SIC
- Biological Products, (No Disgnostic Substances) (2836)
- akta.pro primary industry
- Target Identification & Validation Platforms (omics-driven, chemoproteomics, genetic validation) (HLAAAIAI)
- akta.pro secondary industries
- In Vivo Discovery & Translational Models Platforms (humanized models, PK/PD, efficacy) (HLAAAIAK), Protein Engineering & Directed Evolution Platforms (enzyme/therapeutic protein optimization) (HLAAAIAC)
Keywords
Where ITeos Therapeutics is headquartered
LocationHeadquarters
- HQ city
- Cambridge
- HQ country
- United States
- HQ region
- North America
Markets served
ITeos Therapeutics business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Personnel, Technology or R&D, Operations
ITeos Therapeutics product offering
Product offeringCore offering
ITeos Therapeutics was a clinical-stage biotechnology company that discovered and developed immuno-oncology drug candidates, with its pipeline focused on anti-TIGIT antibodies and other agents designed to modulate the tumor microenvironment and enhance immune-mediated cancer cell killing. The company's lead candidate, belrestotug, was co-developed under a partnership with GSK before that collaboration was terminated in 2025.
Differentiator
Problem solved
Functional benefit
Products and services
- Belrestotug (anti-TIGIT antibody candidate) Clinical-stage anti-TIGIT antibody immunotherapy candidate developed for the treatment of cancer, intended for global development and commercialization through a partnership with GSK before that partnership was terminated in May 2025 following a failed Phase II trial.
Companies that use ITeos Therapeutics
Customer profileIdeal customer profiles2 records
ITeos Therapeutics technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature2 records
ITeos Therapeutics partnerships and signals
Strategic signalPartnerships
One partnership is on record.
- GSKcoreGSK terminated its belrestotug partnership with iTeos in May 2025, leading to the biotech's closure. The partnership was focused on belrestotug development in the immuno-oncology space.
Scale indicators3 records
Recent moves4 records
Expansion highlights2 records
ITeos Therapeutics competitors and assessment
Company assessmentEmerging players
- Surface Oncology (acquired by Coherus BioSciences): Was a clinical-stage immuno-oncology company with anti-TIGIT (SRF388 targeting IL-27) and tumor-microenvironment programs; was acquired by Coherus. Directly relevant precedent for clinical-stage I/O biotechs navigating acquisition outcomes.
- Werewolf Therapeutics: Clinical-stage oncology biotech developing INDUKINE-based tumor-selective immunotherapies. Comparable as an emerging immuno-oncology company pursuing novel immune-engagement mechanisms in the tumor microenvironment.
- Mereo BioPharma: Clinical-stage oncology and rare-disease company with immuno-oncology programs. Comparable as a small-cap clinical biotech with oncology focus, similar headcount scale, and similar dependence on partner-led development.
Broad incumbents
- Bristol Myers Squibb: Major immuno-oncology incumbent (Opdivo, Yervoy) with active TIGIT pathway interest and substantially greater R&D and commercialization resources than iTeos.
- Genentech (Roche): Develops tiragolumab, the leading clinical-stage anti-TIGIT antibody, in combination with atezolizumab across multiple tumor types. Broad incumbent competitor in the TIGIT checkpoint space where iTeos's belrestotug was positioned.
- Merck & Co. Developed vibostolimab (anti-TIGIT) in combination with pembrolizumab. Direct large-pharma competitor in anti-TIGIT combinations, with substantially greater capital and clinical-development resources.
- AstraZeneca: Has pursued anti-TIGIT programs and broad immuno-oncology combinations, representing a major competitor in the I/O landscape where iTeos was positioned.
Regional players
- Akeso Biopharma: China-based biotech that developed ivonescimab, a first-in-class PD-1/VEGF bispecific that has shown competitive readouts against TIGIT-pathway combos. Adjacent competitor in the immuno-oncology combination space where iTeos was positioned.
Direct peers
- Arcus Biosciences: Clinical-stage immuno-oncology company developing anti-TIGIT antibody domvanalimab (in combination with anti-PD-1) — a directly competing anti-TIGIT approach to iTeos's belrestotug, with similar target profile and combination development strategy.
- Compugen: Clinical-stage immuno-oncology company with anti-TIGIT antibody COM902 and a computational target-discovery platform that parallels iTeos's approach to identifying novel immune checkpoints in the tumor microenvironment.
Market position
Strengths3 records
Weaknesses5 records
Competitive moat2 records
Key risks6 records
Key highlights5 records
Customer concentration
ITeos Therapeutics social profiles
Digital presenceITeos Therapeutics financial estimates
Financial estimateRevenue estimate
Valuation estimate
ITeos Therapeutics leadership team
Management profileNumber of profiles
Profiles4 records
ITeos Therapeutics funding detail
Funding detailFunding overview
Funding rounds9 records
Investors17 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
ITeos Therapeutics M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about ITeos Therapeutics
What does ITeos Therapeutics do?
ITeos Therapeutics was a clinical-stage biotechnology company that discovered and developed immuno-oncology drug candidates, with its pipeline focused on anti-TIGIT antibodies and other agents designed to modulate the tumor microenvironment and enhance immune-mediated cancer cell killing. The company's lead candidate, belrestotug, was co-developed under a partnership with GSK before that collaboration was terminated in 2025.
Is ITeos Therapeutics a public or private company?
ITeos Therapeutics is a private company. It is classified as venture growth investor backed and is currently acquired.
When was ITeos Therapeutics founded?
ITeos Therapeutics was founded in 2011. It employs 101 to 250 people.
Where is ITeos Therapeutics based?
ITeos Therapeutics is headquartered in Cambridge, United States, in the North America region.
Who are ITeos Therapeutics's main competitors?
Emerging players on record are Surface Oncology (acquired by Coherus BioSciences), Werewolf Therapeutics and Mereo BioPharma. Broad incumbents are Bristol Myers Squibb, Genentech (Roche), Merck & Co. and AstraZeneca. Akeso Biopharma is listed as a regional player. Direct peers are Arcus Biosciences and Compugen.
Does ITeos Therapeutics have an API?
No public API is recorded for ITeos Therapeutics.
What industry is ITeos Therapeutics in?
ITeos Therapeutics's product category is Immuno-oncology Therapeutics. Its primary akta.pro industry code is HLAAAIAI, Target Identification & Validation Platforms (omics-driven, chemoproteomics, genetic validation), with a secondary code of HLAAAIAK, In Vivo Discovery & Translational Models Platforms (humanized models, PK/PD, efficacy). Its NAICS code is 541714 and its SIC code is 2836.