Cyclerion Therapeutics

What Cyclerion Therapeutics does

Cyclerion Therapeutics (NASDAQ: CYCN) is a clinical-stage biopharmaceutical company headquartered in Cambridge, Massachusetts, founded in April 2019 as a spin-off from Ironwood Pharmaceuticals. The company is developing CYC-126, a drug-device combination therapy for treatment-resistant depression (TRD) that pairs well-characterized anesthetic agents with a personalized biofeedback-driven delivery system using Medsteer's exclusive EEG-guided closed-loop control technology (with underlying MIT-licensed IP and access to datasets from 25+ clinical settings and 9,000 patients). The CYC-126 platform is designed to function as a co-pilot to the anesthesiologist, resetting dysregulated brainwave patterns in the approximately 3 million U.S. patients with TRD who have not responded to conventional therapies. Cyclerion has received constructive FDA feedback on a planned Phase 2 proof-of-concept study using MADRS endpoints, with initial patient enrollment targeted in Australia (H2 2026) and the U.S. (early 2027).

The company operates with 1-10 employees and is pre-revenue, with reported nominal revenue of $2M and a net loss of $976K as of early 2026 against $4.57M cash and $4.19M working capital. Cyclerion has historically generated value through a combination of licensing and asset divestitures: praliciguat was licensed to Akebia Therapeutics for rare kidney disease (FSGS), and the CNS-penetrant sGC stimulators zagociguat and CY3018 were sold to Tisento Therapeutics, in which Cyclerion retains a 10% equity stake. The company's GTM motion is enterprise-clinical, focused on clinical trial site enrollment rather than commercial sales, and its revenue model is licensing/royalty-based on legacy assets with future upside contingent on CYC-126 approval.

In April 2026, Cyclerion entered a definitive all-stock reverse merger agreement with privately held Korsana Biosciences, with the combined company to operate as Korsana Biosciences on Nasdaq under the ticker KRSA. Concurrent with the merger, Korsana secured approximately $380M in private financing from a syndicate led by Fairmount and Venrock Healthcare Capital Partners, with participation from RA Capital Management and Sanofi Ventures, funding the combined entity into 2029. Post-merger, pre-merger Korsana stockholders are expected to own approximately 98.5% of the combined entity, with legacy Cyclerion shareholders retaining approximately 1.5%. The combined company's pipeline will center on Korsana's THETA platform and KRSA-028 (next-generation anti-amyloid beta antibody for Alzheimer's disease), with CYC-126/TRD continuing as a complementary neuropsychiatric asset.

Name

Cyclerion Therapeutics

Legal name

Cyclerion Therapeutics, Inc.

Website

https://cyclerion.com

Company type

Public

Founded year

2019

Operating status

Acquired

Headcount range

1–10 employees

Short description

Cyclerion Therapeutics is a clinical-stage biopharmaceutical company developing CYC-126, a drug-device combination therapy for treatment-resistant depression that pairs anesthetic agents with an EEG-guided closed-loop delivery system. Founded in 2019 as an Ironwood spin-off, Cyclerion is undergoing a reverse merger with Korsana Biosciences.

Ownership category

akta.pro rank

Product category

Clinical-stage biopharmaceuticals (neuropsychiatric)

NAICS

Pharmaceutical Preparation Manufacturing (325412)

SIC

Pharmaceutical Preparations (2834)

akta.pro primary industry

Neurology & CNS Specialty Pharmaceuticals (HLAIACAC)

akta.pro secondary industries

Regulatory Strategy & IND/NDA/BLA Submissions Support (HLAIALAH), Formulation & Preclinical CMC Support (Nonclinical) (HLAGAFAL)

Keywords

• Treatment-resistant depression
• Clinical-stage biopharmaceutical
• Neuropsychiatric drug development
• SGC stimulator therapy
• Drug-device combination

Headquarters

HQ city

Cambridge

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

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

Revenue model

1. Drug Development and Licensing: As a pre-revenue clinical-stage biopharmaceutical company, Cyclerion does not currently generate product revenue. The company is focused on developing its lead asset CYC-126 for treatment-resistant depression through clinical trials. Revenue is anticipated through potential future product licensing, co-development agreements, or commercialization partnerships upon regulatory approval. Legacy assets (praliciguat licensed to Akebia, olinciguat in licensing discussions) may provide non-dilutive capital.
2. Legacy Asset Monetization: Cyclerion is pursuing licensing opportunities for its legacy sGC stimulator assets including olinciguat, and has licensed praliciguat to Akebia Therapeutics for advancement in rare kidney disease. These arrangements may generate future milestone payments and royalties.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels6 records

Core offering

Cyclerion Therapeutics is a clinical-stage biopharmaceutical company developing CYC-126, an individualized therapy for treatment-resistant depression that combines common anesthetic agents with a personalized biofeedback-driven delivery system using EEG-guided closed-loop control. The company also maintains legacy soluble guanylate cyclase (sGC) stimulator assets (olinciguat, praliciguat licensed to Akebia, and zagociguat/CY3018 sold to Tisento) that are being monetized through licensing arrangements.

Product overview

Cyclerion Therapeutics is a neuropsychiatric-focused biopharmaceutical company developing a new pipeline of therapeutics beginning with CYC-126 as its foundational product candidate. CYC-126 is an individualized treatment for treatment-resistant depression (TRD) combining anesthetic agents with a personalized EEG biofeedback-driven delivery system that functions as a closed-loop control platform. The company also maintains legacy assets including olinciguat, praliciguat (licensed to Akebia), and zagociguat/CY3018 (sold to Tisento), which are sGC stimulators targeting various therapeutic areas including cardiovascular, renal, and CNS diseases.

Differentiator

Problem solved

Functional benefit

Products and services

• CYC-126 Individualized therapy for treatment-resistant depression combining common anesthetic agents with a personalized biofeedback-driven delivery system that uses real-time EEG signals to guide dosing. Designed to be the first individualized treatment for TRD, resetting dysregulated brainwave patterns via a closed-loop control platform that functions as a co-pilot to the anesthesiologist.
• Olinciguat Oral soluble guanylate cyclase (sGC) stimulator being evaluated for potential license opportunities. Exhibits diverse pharmacology across cardiovascular, metabolic, renal, and inflammatory disease models.
• Praliciguat Oral, once-daily, systemic sGC stimulator licensed to Akebia Therapeutics for advancement in rare kidney disease. Demonstrated extensive distribution to target tissues including kidney, heart, liver, and adipose tissue in preclinical and clinical studies.
• Zagociguat CNS-penetrant sGC stimulator that has shown rapid improvement in cerebral blood flow, functional brain connectivity, brain response to visual stimulus, cognitive performance, and biomarkers associated with mitochondrial function and inflammation. Sold to Tisento Therapeutics.
• CY3018 Next-generation CNS-targeted sGC stimulator that preferentially localizes to the brain with a pharmacology profile suggesting potential for treatment of neuropsychiatric diseases and disorders. Sold to Tisento Therapeutics.

Quantifiable outcome

• TRD patients have a 2-10x higher incidence of suicide or suicide attempts and 23% higher all-cause mortality vs. MDD patients
• +1 more outcomes

Segments4 records

Ideal customer profiles3 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

AI capability2 records

Feature3 records

Partnerships

Two partnerships are on record, tiered core.

• MedsteercoreTechnology or Integration · 5 January 2026Cyclerion entered an exclusive strategic collaboration with Medsteer to integrate EEG-guided closed-loop control technology into its CYC-126 closed-loop anesthetic platform for treatment-resistant depression. The collaboration grants Cyclerion access to Medsteer's computational modules, control software, and datasets developed across over 25 clinical settings and 9,000 patients. The company also partnered with Medsteer for software integration and formed a clinical advisory board to support development. This collaboration was announced in January 2026 and resulted in a ~44-55% stock surge.
• Paragon Therapeutics (Korsana partnership)coreStrategic or Co-development PartnerKorsana Biosciences developed its THETA platform in partnership with Paragon Therapeutics, enabling the progression of KRSA-028, a next-generation antibody targeting amyloid beta for Alzheimer's disease. This platform is central to the merged company's pipeline following Cyclerion's reverse merger with Korsana.

Scale indicators9 records

Recent moves7 records

Expansion highlights5 records

Broad incumbents

• Acadia Pharmaceuticals: Commercial-stage CNS biopharma with Nuplazid (Parkinson's disease psychosis) and an active neuropsychiatric pipeline; comparable as a broader CNS incumbent with established psychiatry commercial infrastructure.
• Johnson & Johnson: Markets Spravato (esketamine), the first FDA-approved therapy specifically for treatment-resistant depression; the dominant incumbent in the TRD space against which any novel TRD therapy must compete.

Direct peers

• Karuna Therapeutics: CNS-focused company developing xanomeline-trospium (Cobenfy) for schizophrenia with neuropsychiatric pipeline; serves overlapping psychiatry prescriber channels and CNS drug development infrastructure.
• COMPASS Pathways: Developing psilocybin therapy for treatment-resistant depression, targeting the same ~3M US TRD patient population with a novel mechanism requiring supervised clinical administration, analogous to Cyclerion's CYC-126 supervised model.
• Sage Therapeutics: CNS-focused biopharma developing zuranolone (Zurzuvae) for postpartum depression and MDD, with a pipeline overlapping Cyclerion's neuropsychiatric focus and target prescriber base (psychiatrists).
• Axsome Therapeutics: Approved Auvelity (dextromethorphan/bupropion) for MDD and developing treatments for CNS indications including TRD; directly comparable as a focused CNS depression therapeutics competitor.
• Neuphoria Therapeutics (formerly Bionomics): CNS-focused biopharma led by Errol De Souza (also Cyclerion's Chairman), developing treatments for anxiety and depression; directly comparable through shared leadership and CNS pipeline focus.

Others

• Voyager Therapeutics: Gene therapy company for CNS disorders with shared board members (Michael Higgins, Steven Hyman); comparable as a CNS-focused public biopharma navigating similar strategic and financing dynamics, though with a different therapeutic modality.

Emerging players

• Neumora Therapeutics: Clinical-stage CNS biopharma with a broad neuropsychiatric pipeline targeting depression and other brain disorders; comparable as a similarly-sized emerging CNS company pursuing personalized medicine in brain health.
• Alto Neuroscience: Clinical-stage CNS company developing precision medicines for depression and other neuropsychiatric disorders using biomarker-driven patient stratification, conceptually aligned with CYC-126's individualized-treatment positioning.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/Cyclerion
• LinkedInlinkedin.com/company/cyclerion

Revenue estimate

Valuation estimate

Number of profiles

Profiles7 records

Funding overview

Funding rounds4 records

Investors7 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments1 record

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

Frequently asked questions about Cyclerion Therapeutics