What Lirum Therapeutics does

Lirum Therapeutics, Inc. is a privately held, clinical-stage biopharmaceutical company founded in 2021 by the former management team of Stemline Therapeutics (formerly NASDAQ: STML), who previously led the FDA and EMA approval and commercial launch of ELZONRIS. Headquartered at 1270 Avenue of the Americas, 7th Floor, New York, NY, the company operates with 11-50 employees and is focused on the acquisition, development, and commercialization of novel drug candidates for debilitating diseases.

The company's lead and sole disclosed product candidate is LX-101 (formerly 765IGF-MTX), a precision-engineered targeted therapy directed at the insulin-like growth factor-1 receptor (IGF-1R). LX-101 consists of a proprietary, optimized IGF-1 ligand variant conjugated to a cytotoxic methotrexate payload, designed to selectively deliver methotrexate to IGF-1R-expressing cells. The asset has completed Phase 1 trials in advanced pretreated cancer patients with no dose-limiting toxicity or maximum tolerated dose reached, demonstrated IC50s of 6-33 nM across pediatric cancer cell lines, and showed synergy when combined with PI3K or mTOR inhibitors in Ewing sarcoma PDX models. The FDA issued a 'Study May Proceed' letter in October 2025 enabling LX-101's inclusion in the RAPID platform trial for relapsed/refractory Ewing sarcoma and DSRCT at MD Anderson Cancer Center. Lirum is also developing LX-101 in autoimmune disease, with first thyroid eye disease (TED) data presented at NANOS and ARVO in 2025, and is reviewing additional autoimmune indications including rheumatoid arthritis, Graves' disease, Cushing's syndrome, lupus, and Crohn's disease.

Lirum is pre-revenue and generates no commercial product sales. Its business model is structured around progressing LX-101 through clinical development toward regulatory approval and eventual commercialization, supplemented by active business development outreach to acquire or in-license additional drug candidates. The company has closed a single disclosed financing: a $7 million private placement of common stock on February 8, 2023, with ThinkEquity as sole placement agent. Go-to-market relies on scientific conference presentations (AACR, ESMO, CTOS, NANOS, ARVO), investor relations communications, and clinical trial execution through academic medical centers, with no commercial sales infrastructure.

Name

Lirum Therapeutics

Legal name

Lirum Therapeutics, Inc.

Website

https://lirumtx.com

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Lirum Therapeutics is a pre-revenue, clinical-stage biopharmaceutical company developing LX-101, a proprietary IGF-1R-targeted therapy using a methotrexate payload, for pediatric and adult oncology indications and autoimmune disease including thyroid eye disease. Founded 2021; headquartered in New York.

Ownership category

akta.pro rank

Product category

Clinical-stage Biopharmaceuticals

NAICS

Biological Product (except Diagnostic) Manufacturing (325414), Scientific Research and Development Services (5417)

SIC

Biological Products, (No Disgnostic Substances) (2836)

akta.pro primary industry

Cytokines, Interferons & Immunomodulatory Proteins (HLAAAAAC)

akta.pro secondary industries

Rare Immunology, Autoimmune & Autoinflammatory Therapies (HLAIAIAE), Immunology & Inflammation Pharmaceuticals (HLAIAAAD)

Keywords

• Targeted cancer therapy
• Autoimmune disease therapeutics
• Clinical-stage biopharmaceuticals
• IGF-1R targeted therapy
• Antibody-drug conjugates

Headquarters

HQ city

Newyork

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Pharmaceutical Product Revenue: Pre-revenue clinical-stage biopharmaceutical company. Lirum is developing LX-101 through clinical trials toward regulatory approval for oncology and autoimmune indications, with the goal of commercializing the product upon approval. No commercialized products or revenue are currently generated.

Go-to-market motion2 records

Distribution channels1 record

Marketing channels4 records

Core offering

Lirum Therapeutics is developing LX-101, a clinical-stage, precision-engineered targeted therapy directed to the insulin-like growth factor-1 receptor (IGF-1R). LX-101 consists of a proprietary, optimized IGF-1 ligand variant conjugated to a methotrexate payload, enabling targeted delivery to IGF-1R-expressing cancer cells and autoimmune effector cells. The candidate is being advanced for pediatric and adult oncology indications (including Ewing sarcoma, DSRCT, rhabdomyosarcoma, osteosarcoma, neuroblastoma, and GIST) and for autoimmune disease, primarily thyroid eye disease (TED).

Product overview

Lirum Therapeutics is a clinical-stage biopharmaceutical company with a single lead product candidate, LX-101. LX-101 is a novel targeted therapy directed to the insulin-like growth factor 1 receptor (IGF-1R), consisting of a proprietary precision-engineered IGF-1 variant conjugated to a cytotoxic methotrexate payload. The company is developing LX-101 in both oncology (pediatric sarcomas including Ewing sarcoma, DSRCT, rhabdomyosarcoma, osteosarcoma, neuroblastoma, and adult cancers with elevated IGF-1R expression) and autoimmune indications, primarily thyroid eye disease (TED).

Differentiator

Problem solved

Functional benefit

Products and services

• LX-101 (formerly 765IGF-MTX) A novel, clinical-stage, precision-engineered targeted therapy directed to the insulin-like growth factor-1 receptor (IGF-1R). LX-101 consists of a proprietary, optimized IGF-1 ligand variant with high affinity to IGF-1R, conjugated to a cytotoxic methotrexate payload, enabling precise delivery of the payload to IGF-1R+ cells. Being developed for oncology indications (Ewing sarcoma, DSRCT, rhabdomyosarcoma, osteosarcoma, neuroblastoma, GIST, and other IGF-1R-associated adult cancers) and autoimmune disease, primarily thyroid eye disease (TED).

Quantifiable outcome

• In Phase 1 trials, 2/3 (67%) of high IGF-1R-expressing evaluable patients experienced disease control/response, including one objective response at the highest dose.
• +2 more outcomes

Segments3 records

Ideal customer profiles3 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature1 record

Partnerships

Two partnerships are on record, tiered core.

• MD Anderson Cancer CentercoreStrategic or Co-development PartnerCo-authored multiple scientific presentations on LX-101 in Ewing sarcoma and DSRCT with investigators from MD Anderson Cancer Center. The RAPID platform clinical trial for LX-101 in relapsed/refractory Ewing sarcoma and DSRCT is led by Joseph Ludwig, M.D., professor at MD Anderson. This represents the primary clinical development partnership for LX-101 in oncology.
• University of Rochester (Flaum Eye Institute)coreStrategic or Co-development PartnerAcademic collaborator Collynn F. Woeller, Ph.D. from the Flaum Eye Institute at the University of Rochester presented LX-101 thyroid eye disease data at the ARVO 2025 Annual Meeting. The collaboration generated preclinical data demonstrating LX-101's ability to target multiple key processes in TED pathogenesis including inhibition of orbital fibroblasts, reduction of inflammatory cytokines, and modulation of T-cell activity.

Scale indicators2 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• Mersana Therapeutics: Clinical-stage oncology biotech developing a pipeline of targeted antibody-drug conjugates (ADCs) using proprietary payload and linker platforms. Comparable as a clinical-stage targeted biologic company pursuing difficult-to-treat oncology indications.
• Werewolf Therapeutics: Clinical-stage oncology biotech developing targeted immunotherapies (PREDATOR platform) designed to be selectively active in the tumor microenvironment. Comparable clinical-stage targeted oncology biologic profile with IND-stage assets.
• MacroGenics: Clinical-stage oncology biotech developing targeted monoclonal antibody-based therapeutics, including antibody-drug conjugates and bispecifics. Comparable in developing biologic-based targeted oncology therapies with similar development-stage assets.
• Horizon Therapeutics (Amgen): Developed and commercialized Tepezza (teprotumumab), the only FDA-approved IGF-1R-targeted therapy for Thyroid Eye Disease. Most directly comparable peer given shared IGF-1R target in TED; now part of Amgen following the 2023 acquisition.
• Viridian Therapeutics: Clinical-stage biotech developing IGF-1R-targeted antibodies for Thyroid Eye Disease (e.g., VRDN-001, VRDN-003). Directly competes with Lirum's LX-101 in the TED IGF-1R space and represents the most active direct competitor in this indication.
• Bolt Biotherapeutics: Clinical-stage oncology company developing targeted immunotherapies (ISACs — immune-stimulating antibody conjugates) using antibody-payload conjugates. Highly comparable in modality (targeted biologic + cytotoxic payload) and clinical-stage development profile.
• Pyxis Oncology: Clinical-stage oncology biotech developing antibody-drug conjugates (ADCs) and immunotherapies for difficult-to-treat cancers. Comparable business model as a clinical-stage targeted oncology biologic company with similar scale and capital profile.
• CytomX Therapeutics: Clinical-stage oncology biotech developing conditionally activated antibody-based therapeutics (Probody platform) — masked antibodies that activate in the tumor microenvironment. Comparable as a clinical-stage targeted biologic platform company in oncology.

Emerging players

• Inhibrx (acquired by Sanofi): Was a clinical-stage biotech developing targeted biologics including antibody-drug conjugates and engineered proteins for oncology and rare diseases; acquired by Sanofi in 2024. Highly comparable development profile to Lirum prior to acquisition.
• Theseus Pharmaceuticals: Clinical-stage oncology biotech developing targeted kinase inhibitors and biologics for resistance-associated cancers. Comparable as a small clinical-stage oncology company developing targeted therapeutics with similar capital and headcount profile.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

Revenue estimate

Valuation estimate

Number of profiles

Profiles8 records

Funding overview

Funding rounds1 record

Investors

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 Lirum Therapeutics