What Asher Bio does

Asher Biotherapeutics, Inc. ("Asher Bio") is a clinical-stage biopharmaceutical company headquartered in South San Francisco, California, developing cis-targeting immunotherapies for cancer and other diseases. The company's proprietary platform creates fusion proteins combining a cell-type-specific antibody (e.g., anti-CD8beta) with modified cytokine muteins (IL-2, IL-21) that require engagement of two molecules in cis on the same immune cell — an immunomodulatory receptor and the cell-type-specific target — for activation. This architecture is designed to selectively activate only the immune cell subsets that drive therapeutic response (primarily CD8+ effector T cells) while avoiding NK cells and regulatory T cells that drive dose-limiting toxicity or suppress efficacy, addressing the central limitation of conventional cytokine therapies such as IL-2.

The lead program, etakafusp alfa (AB248), is a reduced-potency IL-2 mutein fused to an anti-CD8beta antibody, currently in a Phase 1a/1b clinical trial for locally advanced or metastatic solid tumors both as monotherapy and in combination with pembrolizumab (Merck's KEYTRUDA). Additional disclosed programs include AB821 (CD8-targeted IL-21 in melanoma and solid tumors, Phase 1), AB359 (CD8-targeted IL-2 for chronic hepatitis B), and a cis-targeted cytokine augmentation platform for engineered cell therapies (CAR-T, TCR-T, TILs, NK cells). Initial Phase 1 data presented at ASCO 2026 demonstrated robust CD8+ T cell expansion and a favorable tolerability profile at doses up to 10 µg/kg.

Asher Bio is pre-revenue and serves patients indirectly through clinical trial sites at oncology centers. The company has secured clinical trial collaborations with three large pharmaceutical partners — Merck (pembrolizumab combination), Amgen (IMDELLTRA/tarlatamab combination in small cell lung cancer), and AstraZeneca (rilvegostomig combination in NSCLC) — that supply combination agents and provide validation. The company has raised approximately $218M across a $55M Series A (Third Rock Ventures, March 2021), a $108M Series B (Wellington Management, September 2021), and a $55M Series C (RA Capital, April 2024), with a $150K seed round from Y Combinator in August 2019. Future commercial revenue is contingent on clinical success, regulatory approval, and commercial launch; no commercial products exist today and no pricing has been disclosed.

Name

Asher Bio

Legal name

Asher Biotherapeutics, Inc.

Website

https://asherbio.com

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Asher Bio is a clinical-stage biopharmaceutical company developing proprietary cis-targeting immunotherapies — fusion proteins combining cell-type-specific antibodies with modified cytokine muteins — that selectively activate CD8+ effector T cells to treat cancer and other diseases, currently with lead asset etakafusp alfa in Phase 1 trials.

Ownership category

akta.pro rank

Product category

Cancer Immunotherapy

NAICS

Biological Product (except Diagnostic) Manufacturing (325414), Pharmaceutical and Medicine Manufacturing (3254)

SIC

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

akta.pro primary industry

Cytokines, Interferons & Immunomodulatory Proteins (HLAAAAAC)

akta.pro secondary industries

CAR-T & TCR-T Therapies (HLAAABAC), Bispecific & Multispecific Antibodies (HLAAAAAF)

Keywords

• Cis-targeted immunotherapy
• Cytokine immunotherapy
• Immuno-oncology platform
• CD8 T cell therapy
• Interleukin therapeutics

Headquarters

HQ city

San Francisco

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Pre-Revenue / Clinical-Stage Development: Asher Bio is a pre-revenue clinical-stage biopharmaceutical company. All programs are in clinical development (Phase 1). Revenue generation is contingent on successful clinical development, regulatory approval, and future commercial launch of its immunotherapy pipeline candidates.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

Asher Bio develops cis-targeting cytokine immunotherapies that selectively activate CD8+ effector T cells while avoiding NK cells and regulatory T cells. The lead candidate etakafusp alfa (AB248) is a CD8-targeted IL-2 immunotherapy currently in Phase 1a/1b clinical trials for solid tumors, with pipeline programs including AB821 (IL-21 for melanoma/solid tumors) and AB359 (IL-2 for chronic hepatitis B). The platform also supports cis-targeted augmentation of engineered cell therapies (CAR-T, TCR-T, TILs, NK cells).

Differentiator

Problem solved

Functional benefit

Products and services

• Etakafusp Alfa (AB248) A cis-targeted interleukin-2 (IL-2) immunotherapy that selectively activates CD8+ effector T cells while avoiding NK cells and regulatory T cells. In Phase 1a/1b clinical trials for solid tumors as monotherapy and in combination with pembrolizumab (KEYTRUDA) and tarlatamab (IMDELLTRA).
• AB821 A CD8-targeted interleukin-21 (IL-21) immunotherapy designed to selectively activate CD8+ T cells with enhanced bioavailability, promoting cytotoxicity, memory cell differentiation, and survival. In Phase 1 clinical trials for melanoma and solid tumors.
• AB359 A CD8-targeted IL-2 immunotherapy candidate for chronic hepatitis B virus (HBV), designed to selectively activate CD8+ T cells to drive antiviral activity without the pleiotropy that limits conventional IL-2 therapies. Preclinical stage.
• Cis-Targeted Cytokine Augmentation of Cell Therapies A program developing highly selective cis-targeted IL-2 fusion molecules that specifically activate engineered cell therapies (CAR-T, TCR-T, TILs, NK cells) post-adoptive transfer to enhance engraftment, persistence, and functionality.

Quantifiable outcome

• Phase 1 data demonstrated robust CD8+ T cell expansion and favorable tolerability at doses up to 10 microg/kg

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature2 records

Partnerships

Two partnerships are on record, tiered core.

• Merck (MSD)coreStrategic or Co-development Partner · 1 January 2024Clinical trial collaboration evaluating Asher Bio's AB248 in combination with Merck's anti-PD-1 therapy KEYTRUDA (pembrolizumab). This collaboration leverages the complementary mechanisms of AB248's selective CD8+ T cell activation with KEYTRUDA's checkpoint inhibition to potentially enhance anti-tumor immune responses in solid tumor indications.
• AmgencoreStrategic or Co-development Partner · 1 January 2024Clinical trial collaboration evaluating Asher Bio's etakafusp alfa (AB248) in combination with Amgen's IMDELLTRA (tarlatamab), a bispecific T-cell engager targeting DLL3-expressing small cell lung cancer and other neuroendocrine cancers. This partnership explores the potential of combining selective CD8+ T cell activation with targeted tumor cell killing.

Scale indicators3 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• Nektar Therapeutics: Nektar Therapeutics is a clinical-stage immunology company known for PEGylated IL-2 (bempegaldesleukin) and other cytokine-based programs for oncology, making it a directly comparable peer in engineered IL-2 immunotherapy.
• Neoleukin Therapeutics (now Neurogene after merger): Neoleukin pioneered de novo IL-2 mimetics (NL-201) as selective, non-natural cytokine mimetics for immunotherapy, and is a comparable peer in the selective cytokine agonist space for cancer despite its corporate restructuring.
• Medicenna Therapeutics: Medicenna is developing engineered IL-2 and IL-4 Superkines and fusion proteins designed to selectively bias immune responses, representing a similar cytokine engineering approach to Asher Bio's cis-targeting IL-2/IL-21 programs.
• Werewolf Therapeutics: Werewolf Therapeutics is developing selective, conditionally activated cytokine therapeutics (PREDATOR platform) for cancer, directly mirroring Asher Bio's approach of using engineered cytokines to selectively activate immune cells while limiting off-target effects.

Emerging players

• Compass Therapeutics: Compass Therapeutics is a clinical-stage immuno-oncology company developing bispecific antibodies and combination approaches that engage T cells and the tumor microenvironment, an adjacent emerging peer in selective immune engagement.
• Cullinan Oncology: Cullinan Oncology is a clinical-stage oncology company developing a portfolio of differentiated immuno-oncology therapies, sharing the multi-program clinical biotech profile that Asher Bio aspires to as its pipeline expands.

Broad incumbents

• Sanofi: Sanofi acquired Synthorx to gain access to engineered IL-2 variants (THOR-707) and continues to invest in cytokine-based oncology programs, making it a broad incumbent competitor in selective IL-2 immunotherapy.
• Amgen: Amgen is both a combination partner (IMDELLTRA) and broad incumbent in immuno-oncology with bispecific T-cell engagers and a large oncology pipeline that overlaps with Asher Bio's selective CD8+ T cell activation strategy.
• Merck & Co. Merck is a strategic combination partner for Asher Bio (KEYTRUDA) but is also a broad incumbent in oncology immunotherapy with the leading PD-1 inhibitor, competing indirectly for the same immuno-oncology value pool.
• Roche / Genentech: Roche/Genentech has historically led the IL-2 variant field with IL-2v-based immunocytokines (e.g., cergutuzumab amunaleukin) and maintains a broad oncology immunotherapy portfolio that overlaps with Asher Bio's cis-targeting approach.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat3 records

Key risks5 records

Key highlights7 records

Customer concentration

• Xtwitter.com/AsherBio
• LinkedInlinkedin.com/company/asher-biotherapeutics

Revenue estimate

Valuation estimate

Number of profiles

Profiles19 records

Funding overview

Funding rounds4 records

Investors15 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 Asher Bio