What Actithera does

Actithera is a discovery-stage radiopharmaceutical biotech founded in 2021 that develops next-generation radioligand therapies (RLTs) for cancer. The company targets oncology patients with high unmet medical needs, focusing on tumors that express fibroblast activation protein (FAP) and other cancer-associated targets where conventional chemotherapy and external beam radiation lack sufficient precision. Actithera operates dual headquarters in Cambridge, Massachusetts (US corporate) and Oslo, Norway (R&D), with a small team of 1–10 employees concentrated in radiochemistry, in vivo pharmacology, cell biology, and preclinical imaging.

The company's core technology is a proprietary chemistry platform that combines covalent binding chemistry with an isotope-agnostic design. Covalent ligands form irreversible bonds with tumor-associated proteins, prolonging tumor residence time and enabling more efficient radiation delivery while sparing healthy tissues. The platform is flexible across alpha emitters (²²⁵Ac) and beta emitters (¹⁷⁷Lu, ¹⁶¹Tb), allowing isotope selection based on biological rationale rather than chemistry constraints. The lead asset is a FAP-targeting small molecule RLT currently in IND-enabling studies, supplemented by undisclosed small molecule and peptide pipeline programs. The chemistry platform is reinforced by an exclusive license from Yeda (Weizmann Institute of Science) to two patent families developed in Professor Nir London's laboratory covering site-specific, durable, and traceless radiolabeling.

As a pre-commercial biotech, Actithera does not currently generate product revenue. The intended business model combines pharmaceutical commercialization of approved RLTs through hospital and specialty oncology channels with potential platform licensing to pharmaceutical partners. The $75.5 million Series A financing closed in July 2025 is funding clinical development of the lead FAP asset and expansion of the discovery platform.

Name

Actithera

Legal name

Actithera, Inc.

Website

https://actithera.com

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Actithera is a discovery-stage radiopharmaceutical biotech developing covalent, isotope-agnostic radioligand therapies for cancer, with a lead FAP-targeting small molecule in IND-enabling studies and operations in Cambridge, MA and Oslo.

Ownership category

akta.pro rank

Product category

Radiopharmaceuticals

NAICS

Research and Development in Biotechnology (except Nanobiotechnology) (541714)

akta.pro primary industry

Therapeutic Radiopharmaceuticals (Radioligand/Targeted Radionuclide Therapy) (HLAIAGAB)

akta.pro secondary industry

Theranostic Radiopharmaceutical Platforms (Paired Dx/Tx) (HLAIAGAC)

Keywords

• Radioligand therapy
• Radiopharmaceutical development
• Precision oncology
• Covalent drug chemistry
• Targeted cancer therapeutics

Headquarters

HQ city

Cambridge

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Technology or R&D, Operations, Infrastructure

Revenue model

1. Radiopharmaceutical Development and Commercialization: Pre-commercial biotech company developing a pipeline of radioligand therapies. Revenue model will likely follow traditional pharmaceutical commercialization through prescription-based sales, targeting hospital and specialty oncology clinic channels upon regulatory approval.
2. Platform Licensing and Partnerships: The company may pursue licensing agreements for its proprietary chemistry platform technologies and discovery engine capabilities to pharmaceutical partners.

Go-to-market motion1 record

Marketing channels4 records

Core offering

Actithera is a discovery-stage radiopharmaceutical biotech that develops next-generation radioligand therapies (RLTs) by linking radioactive isotopes to proprietary small molecule and peptide ligands. Its lead asset is a FAP-targeting small molecule radioligand therapy in IND-enabling studies, supported by a covalent chemistry platform that prolongs tumor retention and is isotope-agnostic across alpha and beta emitters.

Product overview

Actithera is a discovery-stage radiopharmaceutical biotech company with a proprietary chemistry platform for developing next-generation radioligand therapies (RLTs). The core portfolio includes a lead FAP-targeting small molecule radioligand therapy currently in IND-enabling studies, supported by an exclusive license to Weizmann Institute's covalent chemistry technologies. The platform is isotope-agnostic, enabling use of alpha or beta emitters (¹⁷⁷Lu, ²²⁵Ac, ¹⁶¹Tb), and supports a pipeline of undisclosed small molecule and peptide programs across discovery and preclinical stages.

Differentiator

Problem solved

Functional benefit

Products and services

• FAP-Targeting Radioligand Therapy Lead small molecule radiopharmaceutical therapy developed by Actithera targeting fibroblast activation protein (FAP). Designed to persist in tumors while sparing healthy tissues through proprietary covalent chemistry; currently in IND-enabling studies for cancer patients.
• Radioligand Therapy Platform Proprietary chemistry platform for discovering and developing next-generation radioligand therapies with superior tumor retention, isotope-agnostic design, and applicability across diverse cancer targets including small molecules and peptides.
• Undisclosed Pipeline Programs Pipeline of undisclosed small molecule and peptide-based radioligand therapies targeting various cancer indications, at different discovery and preclinical stages.

Quantifiable outcome

• More efficient and sustained radiation delivery to tumors through prolonged tumor retention
• +2 more outcomes

Segments1 record

Ideal customer profiles2 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.

• Yeda / Weizmann Institute of SciencecoreTechnology or Integration · 14 October 2025Exclusive license agreement for two patent families covering covalent chemistry technologies developed in Professor Nir London's laboratory. These technologies enable site-specific, durable, and traceless radiolabeling of tumor-specific proteins, designed to enhance tumor selectivity and retention in radiopharmaceuticals for cancer treatment. Integration into Actithera's existing discovery platform supports next-generation RLT design across oncology indications.

Scale indicators4 records

Recent moves5 records

Expansion highlights5 records

Broad incumbents

• Novartis: Novartis commercializes Pluvicto (177Lu-PSMA-617) and Lutathera, the dominant approved radioligand therapies that define the market Actithera is targeting. Actithera's CMO Dr. Dalal previously led radioligand development at Novartis, making it both the gold-standard incumbent and a likely future acquirer/partner.
• Bayer: Bayer operates Xofigo (Ra-223) and is actively investing in next-generation radiopharmaceuticals through its pharma division. Bayer has been an aggressive acquirer of radiopharma assets and represents a major strategic competitor and potential acquirer.
• Lantheus Holdings: Lantheus is a specialized radiopharmaceutical company with commercial products including Pylarify (Pyl-PSMA, a PSMA PET imaging agent). Lantheus's theranostic focus and commercial radiopharma infrastructure make it a direct comparable in the diagnostic+therapeutic radiopharmaceutical space.
• Telix Pharmaceuticals: Telix is a commercial-stage radiopharmaceutical company with multiple approved imaging agents and an expanding therapeutic pipeline. Its PSMA imaging franchise and growing RLT pipeline make it a key direct competitor for both diagnostic and therapeutic market share.

Direct peers

• ITM Isotope Technologies: ITM is a therapeutic radiopharmaceutical biotech developing targeted radionuclide therapies, with proprietary177Lu production capabilities. ITM's pipeline of oncology RLTs and isotope supply positioning make it a direct comparable in therapeutic radiopharmaceutical development.
• Philochips: Philochips is an emerging RLT biotech pursuing FAP-targeting radioligand therapies—the same target as Actithera's lead asset. Direct head-to-head competition on FAP, a validated oncology target, makes Philochips the closest direct peer on the lead program.
• Mariana Oncology: Mariana Oncology was a radioligand therapy platform company with a diversified pipeline across multiple targets and radionuclides—recently acquired by GSK for up to $1.7B. Mariana's platform model and similar stage pre-acquisition make it a highly comparable peer, demonstrating pharma appetite for radiopharma platforms.
• RayzeBio: RayzeBio developed actinium-225-based radiopharmaceuticals and was acquired by Bristol-Myers Squibb for $4.1B in 2024. RayzeBio's alpha-emitter focus and similar pre-commercial stage profile make it a benchmark comparable for both platform value and likely acquisition outcomes.
• Fusion Pharmaceuticals: Fusion Pharmaceuticals developed targeted alpha therapies (TAT) using actinium-225 and was acquired by AstraZeneca for $2.4B in 2024. Fusion's alpha-emitter radiopharma platform and oncology focus directly parallel Actithera's isotope-agnostic, covalent-chemistry approach.
• Ariceum Therapeutics: Ariceum is an emerging radiopharmaceutical biotech developing RLTs for cancer with a focus on targets including somatostatin receptors and other oncology indications. As a private, clinical-stage RLT biotech, Ariceum offers a close comparable for Actithera's development trajectory and fundraising profile.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks6 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/actithera

Revenue estimate

Valuation estimate

Number of profiles

Profiles7 records

Funding overview

Funding rounds1 record

Investors9 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 Actithera