What Aethon Therapeutics does

Aethon Therapeutics is a privately held, preclinical-stage biopharmaceutical company founded in 2022 and headquartered in New York City (incorporated in Delaware), developing antibody therapeutics that selectively kill drug-resistant cancer cells. The company is built around its proprietary HapImmune™ platform, which creates synthetic neoantigens by design: when targeted covalent inhibitors (TCIs) bind their oncogenic driver proteins (e.g., KRASG12C, EGFR), the resulting drug–target peptide conjugates (haptens) are presented on tumor cell surfaces via MHC/HLA molecules, and Aethon's antibodies are engineered to recognize these drug–peptide:HLA complexes while sparing wild-type peptides. Lead named candidates include bispecific T cell engagers AETX-R114 (paired with sotorasib) and AETX-R302 (paired with divarasib), designed to recruit cytotoxic T cells to KRASG12C inhibitor-resistant cancer cells with cross-HLA coverage.

The platform is exclusively licensed from NYU Langone Health and relies on NYU's 100-billion-sequence synthetic antibody repertoire for antibody discovery. Aethon's business model is asset-light and partnership-driven: the company is pre-revenue and not yet selling products, generating near-term inflows via strategic collaborations — most notably a multi-year deal with Revolution Medicines (announced April 2024) covering RAS(ON) inhibitor–directed bispecific antibody discovery, with full preclinical reimbursement plus upfront and contingent downstream payments tied to option exercise for clinical development and commercialization. Its longer-term monetization path is one-time licensing, milestone payments, and royalties on any partnered or independently commercialized therapeutic, distributed through standard pharmaceutical channels.

Aethon was co-founded by Apple Tree Partners (ATP), which led the $30M Series A in January 2023, alongside NYU Langone Health, and is led by CEO Paul Da Silva Jardine, Ph.D. (former Pfizer CVMD research head, ex-CEO of Staten Biotechnology acquired by Novo Nordisk) with scientific founders Shohei Koide, Ph.D. and Benjamin G. Neel, M.D., Ph.D. of NYU serving as advisors and platform inventors. The company employs 11–50 people in New York, continues to recruit immunology, antibody engineering, and peptidomics scientists, and is signaling clinical readiness through peer-reviewed publications (Cancer Discovery, Nature Communications) and AACR 2025 presentations.

Name

Aethon Therapeutics

Legal name

Aethon Therapeutics, Inc.

Website

https://aethontx.com

Company type

Private

Founded year

2022

Operating status

Operating

Headcount range

11–50 employees

Short description

Aethon Therapeutics is a preclinical-stage biotech developing the HapImmune™ platform, which engineers bispecific antibodies that selectively kill drug-resistant cancer cells by recognizing drug–peptide:HLA complexes created by targeted covalent inhibitors of oncogenic drivers such as KRASG12C.

Ownership category

akta.pro rank

Product category

Oncology Biopharmaceuticals

NAICS

Research and Development in Biotechnology (except Nanobiotechnology) (541714), Biological Product (except Diagnostic) Manufacturing (325414)

SIC

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

akta.pro primary industry

Bispecific & Multispecific Antibodies (HLAAAAAF)

akta.pro secondary industry

Personalized Therapeutic Design (neoantigen vaccines, individualized cell/gene therapies) (HLAAANAK)

Keywords

• Cancer immunotherapy
• Antibody therapeutics
• Bispecific T cell engagers
• Targeted oncology
• Drug-resistant cancer

Headquarters

HQ city

New York

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, Marketing or Sales, Others

Revenue model

1. Therapeutic Development and Commercialization: Pre-revenue biopharmaceutical company developing novel antibody therapeutics for cancer treatment. Revenue will be generated through potential product sales and licensing arrangements following regulatory approval.
2. Strategic Partnerships and Collaborations: Multi-year collaboration with Revolution Medicines includes upfront payments and potential downstream payments covering future development and commercialization activities should Revolution Medicines exercise its option.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

Aethon Therapeutics is a clinical-stage biopharmaceutical company that engineers novel antibody therapeutics using its proprietary HapImmune™ platform. The company combines immunotherapy with targeted covalent inhibitors (TCIs) of RAS, EGFR, and other oncogenic driver mutations to create synthetic neoantigens that bispecific T cell engagers can recognize, enabling selective killing of drug-resistant cancer cells including persister cells that survive targeted therapy.

Product overview

Aethon Therapeutics is a biotechnology company that has developed a unified platform approach centered on the HapImmune™ platform. The company's portfolio consists of novel anti-drug-peptide conjugate/MHC antibodies and bispecific T cell engagers, including named candidates AETX-R114 (sotorasib companion) and AETX-R302 (divarasib companion). These products are designed to work in combination with targeted covalent inhibitors of RAS, EGFR, and other oncogenic mutations to selectively kill drug-resistant cancer cells by enabling immune detection of treatment-induced neoantigens.

Differentiator

Problem solved

Functional benefit

Products and services

• HapImmune™ Platform A proprietary drug discovery platform that creates antibodies to recognize drug-peptide complexes (haptens) presented by MHC molecules on tumor cells. Uses NYU Langone Health's repertoire of 100 billion synthetic antibody sequences to identify antibodies that target covalent inhibitor-generated neoantigens while avoiding wild-type peptides. The platform produces bispecific T cell engagers with one arm directed toward drug-peptide:HLA and another toward anti-CD3 and/or other T cell surface proteins.
• AETX-R114 (sotorasib companion) A bispecific T cell engager designed to bind drug-modified KRASG12C peptide:MHC complexes generated by sotorasib treatment, recruiting T cells to selectively kill KRASG12C inhibitor-resistant cancer cells. Designed for use in combination with sotorasib to overcome acquired resistance in KRASG12C-mutated cancers.
• AETX-R302 (divarasib companion) A bispecific T cell engager designed to bind drug-modified KRASG12C peptide:MHC complexes generated by divarasib treatment, enabling cross-HLA recognition and potent T-cell-mediated killing of inhibitor-resistant cancer cells. Designed for use in combination with Revolution Medicines' RAS(ON) inhibitors.
• Anti-Drug-Peptide Conjugate/MHC Antibodies A class of novel antibody therapeutics designed to be used in combination with targeted covalent inhibitors (TCI) of RAS, EGFR, and other oncogenic driver mutations. These antibodies mount immune attacks that selectively kill residual cancer cells including drug-resistant persister cells, addressing treatment resistance in cancer therapy.
• Bispecific T Cell Engagers (Platform Output) Engineered antibodies produced by the HapImmune™ platform with one arm directed toward drug-peptide:HLA complexes and another toward anti-CD3 and/or other T cell surface proteins to recruit cytotoxic T cells to tumor cells. Used to mount selective immune attacks on cancer cells displaying covalent inhibitor-generated neoantigens.

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

Two partnerships are on record, tiered core.

• Revolution MedicinescoreStrategic or Co-development Partner · 4 April 2024Aethon will use its HapImmune™ platform to discover novel bispecific antibodies directed towards cancer cells hit by Revolution Medicines' RAS(ON) inhibitors. Multi-year collaboration with full preclinical work reimbursement by Revolution Medicines. Revolution Medicines has option to conduct clinical development with upfront and potential downstream payments covering future development and commercialization.
• NYU Langone HealthcoreStrategic or Co-development Partner · 9 January 2023NYU Langone Health's Perlmutter Cancer Center researchers Shohei Koide, Ph.D. and Benjamin G. Neel, M.D., Ph.D. co-founded Aethon and serve as scientific advisors. NYU Langone Health exclusively licensed pending patent applications and expertise covering the HapImmune™ platform to Aethon, participated in Series A funding, and holds equity in the company.

Scale indicators2 records

Recent moves7 records

Expansion highlights5 records

Direct peers

• Revolution Medicines: Revolution Medicines is Aethon's strategic partner and a leading RAS(ON) inhibitor developer. Both companies work in the RAS-driven oncology space and co-develop antibody-RAS inhibitor combinations; RevMed's clinical pipeline determines the addressable market for Aethon's companion bispecifics.
• Mirati Therapeutics: Mirati developed divarasib (G12C inhibitor) and was acquired by Bristol Myers Squibb. Aethon's AETX-R302 is designed as a divarasib companion, putting the two companies in a tightly coupled commercial and scientific relationship in KRASG12C combination therapy.
• Erasca: Erasca is a clinical-stage precision oncology company developing RAS/MAPK pathway inhibitors. Comparable to Aethon in stage and focus on RAS-driven cancers, with overlapping interest in combination strategies to overcome resistance.
• Black Diamond Therapeutics: Black Diamond is a precision oncology biotech developing allosteric mutant-selective inhibitors across oncogenic drivers. Comparable in stage, focus on resistance mutations, and emphasis on master-key targeting of oncogenic proteins.

Broad incumbents

• Amgen: Amgen markets sotorasib (Lumakras), the first FDA-approved KRASG12C inhibitor and the drug that Aethon's AETX-R114 is designed to complement. Amgen's commercial trajectory and lifecycle management decisions directly shape Aethon's commercial opportunity.
• Harpoon Therapeutics: Harpoon developed T cell engagers for solid tumors and was acquired by Merck in 2024. Directly relevant as a bispecific T cell engager peer in oncology, with shared challenges of solid-tumor immune engagement that Aethon's HapImmune candidates must solve.
• BioNTech: BioNTech is a major biopharmaceutical company with broad immunotherapy and neoantigen programs, including the immunopeptidomics/MHC-I expertise that Aethon's Executive Director Lauren Stopfer helped build. Comparable as a competitor in MHC-restricted neoantigen targeting.

Emerging players

• Foghorn Therapeutics: Foghorn is a clinical-stage biotech developing medicines targeting chromatin biology in cancer. While its mechanism differs, Foghorn is a similarly staged, similarly capitalized oncology platform company pursuing genetically defined patient populations.
• Theseus Pharmaceuticals: Theseus developed next-generation tyrosine kinase inhibitors designed to address resistance mutations in oncology. Comparable to Aethon in its focus on overcoming resistance to targeted therapies in cancer, although Theseus has since restructured.
• Marengo Therapeutics: Marengo is a clinical-stage precision immuno-oncology company developing T cell receptor-based therapies. Comparable to Aethon in targeting intracellular tumor antigens via innovative antibody engineering for solid-tumor oncology.

Market position

Strengths1 record

Weaknesses1 record

Competitive moat4 records

Key risks5 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/aethon-therapeutics

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds1 record

Investors2 records

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M&A

Investments

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Frequently asked questions about Aethon Therapeutics