What Synthekine does

Synthekine is a private, clinical-stage biotherapeutics company founded in 2018 and headquartered in Menlo Park, California, that engineers next-generation cytokine therapeutics for oncology and autoimmune/inflammatory diseases. The company deploys three proprietary cytokine engineering platforms: Cytokine Partial Agonists (which tune receptor binding to decouple efficacy from toxicity), Orthogonal IL-2 (orthoIL-2) Technology (which creates engineered ligand-receptor pairs independent of the endogenous cytokine system to enable controlled in vivo expansion of cell therapies), and Surrogate Cytokine Agonists (SCAs) (which dimerize or multimerize receptor subunits in non-natural configurations to create novel cell selectivity). The lead clinical asset STK-012, an α/β-biased IL-2 partial agonist, is in a global randomized Phase 2 trial (SYNERGY-101) in first-line PD-L1 negative nonsquamous NSCLC and has generated a 50% Phase 1b response rate versus 23-32% for standard treatments; SYNCAR-001 combined with STK-009 (orthogonal IL-2 plus CD19 CAR-T) received FDA Fast Track Designation for lupus without lymphodepletion.

Synthekine operates as a pre-revenue clinical-stage biotech with no commercialized products and derives its capital base from equity financings — $82M Series A (2020), $107.5M Series B (2021), and $100M Series C (2023), totaling approximately $313M from investors including Canaan Partners, Samsara BioCapital, The Column Group, Deerfield Management, and Janus Henderson Investors. The go-to-market model combines internal pipeline development with strategic pharma collaborations: a 2021 worldwide research and licensing agreement with Merck leveraging the SCA platform, a January 2024 strategic collaboration with Sanofi on selective IL-10 receptor agonists for inflammatory disease, and a February 2026 clinical trial collaboration with Merck to evaluate STK-012 plus Keytruda in the SYNERGY-101 study. Future revenue mechanics depend on partnership upfronts, milestone payments, and royalties rather than direct sales.

The company serves patients in oncology (solid tumors including NSCLC, hepatocellular carcinoma; CD19+ hematologic malignancies) and autoimmune/inflammatory disease (systemic lupus erythematosus and related conditions), with scientific leadership grounded in founder K. Christopher Garcia's Stanford structural biology research, CMO Naiyer Rizvi's checkpoint immunotherapy track record, and a board that includes the scientific leads behind ipilimumab and nivolumab discovery. Synthekine retains worldwide rights to its core programs and employs 51-100 people across its single Menlo Park headquarters.

Name

Synthekine

Legal name

Synthekine, Inc.

Website

https://synthekine.com

Company type

Private

Founded year

2019

Operating status

Operating

Headcount range

51–100 employees

Short description

Synthekine is a pre-revenue, clinical-stage biotherapeutics company engineering selective cytokine therapeutics via three platforms — Cytokine Partial Agonists, Orthogonal IL-2, and Surrogate Cytokine Agonists — for oncology and autoimmune diseases, with lead asset STK-012 in Phase 2 for NSCLC.

Ownership category

akta.pro rank

Product category

Cytokine Therapeutics / Biopharmaceuticals

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

Cytokines, Interferons & Immunomodulatory Proteins (HLAAAAAC)

akta.pro secondary industries

Engineered Protein Therapeutics (de novo/AI-designed proteins, novel scaffolds) (HLAAAAAJ), Immunology & Inflammation Pharmaceuticals (HLAIAAAD), Immunology & Autoimmune Specialty Pharmaceuticals (HLAIACAB), Cell Therapy Developers (Allogeneic/Off-the-shelf) (HLAAABAB)

Keywords

• Engineered cytokine therapeutics
• Cytokine partial agonists
• Orthogonal IL-2 therapeutics
• Immuno-oncology biopharmaceuticals
• CAR-T combination therapies

Headquarters

HQ city

Menlo Park

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. Pharmaceutical Product Revenue: Pre-revenue clinical stage biotech company. Revenue expected from commercialization of cytokine therapeutic pipeline including STK-012 (Phase 2), STK-026 (IND enabling), and cell therapy programs. Partnerships with Merck and Sanofi provide upfront payments and potential milestone payments plus royalties.
2. Strategic Collaboration Payments: Collaboration agreements with pharmaceutical partners generate upfront payments, research funding, development milestones, and commercial royalties. Examples include Sanofi IL-10 collaboration and Merck surrogate cytokine agonist platform partnership.

Go-to-market motion2 records

Distribution channels1 record

Marketing channels4 records

Core offering

Synthekine discovers, develops and plans to commercialize engineered cytokine therapeutic candidates for cancer and autoimmune, inflammatory, and metabolic diseases. Its lead clinical programs include STK-012 (IL-2 partial agonist in Phase 2 for non-small cell lung cancer), STK-009 + SYNCAR-001 (orthogonal IL-2 paired with CD19 CAR-T, FDA Fast Track designated for lupus), and STK-026 (IL-12 partial agonist). The company monetizes its pipeline through a mix of internal development, co-development partnerships (Merck, Sanofi) and milestone/royalty-bearing licensing agreements.

Differentiator

Problem solved

Functional benefit

Products and services

• STK-012 STK-012 is an α/β-biased IL-2 partial agonist designed to preferentially stimulate tumor-killing T cells while avoiding toxicity from NK cells and naïve T cells. It is in Phase 2 (SYNERGY-101) for first-line PD-L1 negative non-squamous NSCLC, with Phase 1b data showing a 50% response rate vs. 23-32% with standard treatments in this population.
• STK-009 + SYNCAR-001 (CD19 CAR-T combination) Combination of STK-009, an orthogonal IL-2 ligand, with SYNCAR-001, a CD19 CAR-T cell therapy engineered to express the orthogonal IL-2 receptor. Designed to deliver highly selective proliferation and activation in vivo, removing the need for lymphodepletion and increasing durability and potency of adoptive cell therapies. Indication targets include CD19+ hematologic malignancies and lupus.
• STK-026 STK-026 is a detoxified IL-12 partial agonist designed to sustain CD8+ T cell activity while reducing NK-mediated cytokine release and toxicities associated with wild-type IL-12. Program is in IND-enabling development.
• Selective IL-10 receptor agonist program (Sanofi collaboration) Selective IL-10 receptor agonists developed through Synthekine's cytokine partial agonist platform for the treatment of inflammatory and autoimmune diseases. Licensed to Sanofi under a strategic collaboration; Synthekine performs research through preclinical stage, after which Sanofi assumes preclinical, clinical, and commercial responsibility.
• Surrogate Cytokine Agonists (SCA) platform program (Merck collaboration) Surrogate Cytokine Agonists developed using Synthekine's SCA platform, which dimerizes or multimerizes cytokine receptor subunits in ways wild-type cytokines cannot, enabling non-natural receptor pairing. Licensed to Merck for up to two cytokine targets, with Synthekine performing initial research and Merck holding exclusive development, manufacturing and commercialization rights.

Quantifiable outcome

• 50% response rate with STK-012 in PD-L1 negative NSCLC vs 23-32% with standard treatments
• +1 more outcomes

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

Three partnerships are on record, tiered core and flagship.

• Merck (MSD)coreStrategic or Co-development Partner · 26 February 2026Clinical trial collaboration and supply agreement to evaluate STK-012 in combination with Keytruda (pembrolizumab) and chemotherapy in the SYNERGY-101 randomized Phase 2 study for first-line PD-L1 negative nonsquamous NSCLC. Merck supplies Keytruda for the combination regimen. Both companies retain commercial rights to their respective compounds as monotherapies or in combination regimens.
• SanoficoreStrategic or Co-development Partner · 25 January 2024Strategic collaboration to develop and commercialize selective IL-10 receptor agonists for the treatment of inflammatory diseases. Collaboration focuses on advancing Synthekine's multiple approaches to optimizing IL-10. Synthekine and Sanofi collaborate on research activities up to a defined point of preclinical development, after which Sanofi assumes responsibility for preclinical, clinical, and commercial activities.
• Merck (MSD)flagshipStrategic or Co-development Partner · 1 November 2021Worldwide research collaboration and licensing agreement leveraging Synthekine's proprietary surrogate cytokine agonist platform to discover, develop and commercialize novel cytokine therapeutics. Synthekine responsible for initial research efforts in collaboration with Merck, and Merck has exclusive rights to develop, manufacture and commercialize surrogate cytokine agonists for up to two cytokine targets.

Scale indicators6 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Xilio Therapeutics: Clinical-stage biotech with tumor-activated immunotherapies including engineered cytokines and immune cell engagers. Competes in the same immuno-oncology and cytokine-engineering space as Synthekine, with a focus on selective activation in the tumor microenvironment.
• Werewolf Therapeutics: Clinical-stage biotech developing PREDATOR platform-engineered cytokine therapeutics (INDUKINEs) for oncology. Most direct comparable to Synthekine's engineered-cytokine approach and selective IL-2/IL-12 partial agonism, with multiple programs in clinical development for solid tumors.
• Neoleukin Therapeutics: Predecessor-stage company that pioneered de novo protein design for cytokine mimetics (NL-201, a de novo IL-2/IL-15 mimetic) and merged with Medicenna. Important historical comparator for Synthekine's engineered cytokine approach, particularly the surrogate cytokine agonist concept.
• Medicenna Therapeutics: Clinical-stage company developing engineered cytokine variants (IL-2, IL-4, IL-13 Superkines) for oncology and autoimmune disease. Closely comparable to Synthekine's protein-engineered cytokine strategy, including selective agonists designed to address wild-type cytokine pleiotropy.

Emerging players

• Allogene Therapeutics: Clinical-stage allogeneic CAR-T developer with a broad pipeline of off-the-shelf cell therapies. Comparable to Synthekine's SYNCAR-001 + STK-009 CAR-T + orthogonal IL-2 program as it advances into autoimmune indications like lupus without lymphodepletion.
• Cugene: Clinical-stage biotech developing engineered IL-2 and IL-15 cytokine variants (e.g., CUG252) for autoimmune disease. Directly comparable to Synthekine's engineered cytokine efforts in inflammation/autoimmune indications.
• Compass Therapeutics: Clinical-stage biotech developing a portfolio of antibody-based therapeutics including bispecifics that engage immune cells, with mechanistic overlap to Synthekine's immuno-oncology programs (e.g., next-generation immune agonists targeting similar biology).

Broad incumbents

• Nektar Therapeutics: Established biopharma with a long history in engineered cytokine (PEGylated IL-2, bempegaldesleukin) and immuno-oncology development. A broader incumbent reference point in the cytokine engineering field, including the high-profile Phase 3 failure of bempegaldesleukin that informs sector risk.

Others

• CytomX Therapeutics: Clinical-stage biotech with Probody platform for conditionally activated biologics in oncology. Highly relevant as a proxy because Synthekine CEO Debanjan Ray was previously CFO/head of corporate development at CytomX, and the company shares investor syndicate overlap (Canaan, Samsara).
• AnaptysBio: Clinical-stage immunology company developing antibody therapeutics for inflammatory and autoimmune disease. Relevant given the overlap of Synthekine's new Board Chair John Orwin (also AnaptysBio Chair) and shared focus on selective immune modulation in autoimmune disease.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/synthekine
• LinkedInlinkedin.com/company/synthekine

Revenue estimate

Valuation estimate

Number of profiles

Profiles12 records

Funding overview

Funding rounds3 records

Investors11 records

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M&A

Investments

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

Frequently asked questions about Synthekine