What Cellectar Biosciences does

Cellectar Biosciences, Inc. (NASDAQ: CLRB) is a late-stage clinical biopharmaceutical company founded in 2002 and headquartered in Florham Park, New Jersey, that develops targeted radiopharmaceutical cancer therapies using its proprietary Phospholipid Drug Conjugate (PDC) platform. The PDC platform exploits lipid raft microdomains in tumor cell plasma membranes to selectively deliver radioisotope and cytotoxic payloads to cancer cells while sparing healthy tissue, and supports multiple emission modalities — beta (I-131), Auger (I-125), and alpha (Ac-225) — from a single targeting chassis.

The company's lead product candidate is Iopofosine I 131 (CLR 131), a first-in-class PDC delivering iodine-131, which is advancing toward an FDA accelerated approval filing in relapsed/refractory Waldenström Macroglobulinemia (WM). Updated 12-month Phase 2b CLOVER WaM data showed an 83.6% overall response rate and 61.8% major response rate in WM patients. Iopofosine has accumulated Breakthrough Therapy, six Orphan Drug, two Fast Track, and four Rare Pediatric Disease designations from the FDA, plus EMA PRIME and Orphan Drug designations and Conditional Marketing Authorization feedback for the EU. The pipeline additionally includes CLR 125 (Auger-emitting, Phase 1b in triple-negative breast cancer) and CLR 225 (alpha-emitting actinium-225 program with preclinical activity in pancreatic and other solid tumors), both leveraging the same PDC delivery chassis.

Cellectar is pre-revenue with no commercialized products. Its business model depends on securing regulatory approval and then distributing iopofosine directly to hospitals and cancer treatment centers with radiopharmacy capabilities, supplemented today by NCI/NIH grant funding and recurring equity financings. The most recent capital event is the May 2026 oversubscribed financing of up to $140 million led by Nantahala Capital, intended to fund a confirmatory Phase 3 study in WM and an FDA accelerated approval filing. As of March 31, 2026, the company held approximately $8.3 million in cash and reported an accumulated deficit of $274.9 million as of December 31, 2025, with operating losses reflecting ongoing clinical development rather than commercial activity.

Name

Cellectar Biosciences

Legal name

Cellectar Biosciences, Inc.

Website

https://cellectar.com

Company type

Public

Founded year

2002

Operating status

Operating

Headcount range

11–50 employees

Short description

Cellectar Biosciences is a late-stage clinical biopharmaceutical company developing targeted radiopharmaceutical cancer therapies using its proprietary Phospholipid Drug Conjugate (PDC) platform, with lead asset Iopofosine I 131 advancing toward FDA accelerated approval in Waldenström Macroglobulinemia.

Ownership category

akta.pro rank

Product category

Targeted Radiopharmaceutical Cancer Therapies

NAICS

Pharmaceutical and Medicine Manufacturing (3254), Research and Development in Biotechnology (except Nanobiotechnology) (541714)

SIC

Pharmaceutical Preparations (2834)

akta.pro primary industry

Therapeutic Radiopharmaceuticals (Radioligand/Targeted Radionuclide Therapy) (HLAIAGAB)

akta.pro secondary industry

Theranostic Radiopharmaceutical Platforms (Paired Dx/Tx) (HLAIAGAC)

Keywords

• Targeted cancer therapy
• Phospholipid drug conjugates
• Radiopharmaceutical oncology
• Hematologic cancer treatment
• Clinical stage biopharmaceuticals

Headquarters

HQ city

Madison

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

Revenue model

1. Pharmaceutical Product Sales (Future): Once regulatory approvals are obtained, the company plans to generate revenue through direct sales of iopofosine I 131 and future PDC-based therapeutics to hospitals, cancer treatment centers, and specialty pharmacies. Revenue model will involve specialty pharmaceutical distribution with hospital/health system contracting.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels6 records

Core offering

Cellectar Biosciences is a late-stage clinical biopharmaceutical company developing targeted radiopharmaceutical cancer therapies built on its proprietary Phospholipid Drug Conjugate (PDC) platform. Its lead clinical asset, Iopofosine I 131, delivers iodine-131 selectively to cancer cells via lipid raft targeting, with ongoing Phase 2b/Phase 3 programs in Waldenström Macroglobulinemia, multiple myeloma, CNS lymphoma, and pediatric high-grade glioma, plus earlier-stage Auger- and alpha-emitting PDC candidates for solid tumors.

Product overview

Cellectar Biosciences is a late-stage clinical biopharmaceutical company developing a portfolio of targeted cancer therapies using its proprietary Phospholipid Drug Conjugate (PDC) platform. The company's lead product is Iopofosine I 131, a first-in-class beta-emitting radioconjugate for treating relapsed or refractory Waldenström Macroglobulinemia and other hematologic cancers. The pipeline includes CLR 125 (iodine-125 Auger-emitting program for solid tumors) and CLR 225 (actinium-225 alpha-emitting program), both leveraging the PDC platform to selectively deliver radioisotopes to cancer cells while minimizing off-target effects.

Differentiator

Problem solved

Functional benefit

Products and services

• Iopofosine I 131 (CLR 131) First-in-class Phospholipid Drug Conjugate delivering iodine-131 radioisotope selectively to cancer cells via lipid raft targeting; in development for relapsed/refractory Waldenström Macroglobulinemia, multiple myeloma, CNS lymphoma, and pediatric high-grade glioma.
• CLR 125 (CLR 121125) Iodine-125 Auger-emitting PDC program targeting solid tumors including triple-negative breast cancer, lung, and colorectal cancer; currently in a Phase 1b dose-finding study in TNBC to determine the recommended dose for a subsequent Phase 2 trial.
• CLR 225 (CLR 121225) Actinium-225 based alpha-emitting PDC program targeting solid tumors with high unmet need such as pancreatic cancer; has shown activity in multiple solid tumor animal models including pancreatic, colorectal, and breast cancers.

Quantifiable outcome

• Objective response rate data from CLOVER trial pending completion
• +1 more outcomes

Named customers4 records

Segments2 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

One partnership is on record.

• Ionetix CorporationcoreOthers · 1 December 2025Multi-year supply agreement for Actinium-225 and Astatine-211 radioisotopes. Ionetix provides reliable supply of alpha-emitting radioisotopes critical for the company's CLR 125 and future alpha-particle therapy programs using the PDC platform.

Scale indicators6 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• Telix Pharmaceuticals: Commercial-stage radiopharmaceutical company developing targeted radiation therapies and imaging agents for oncology, including prostate cancer (Illuccix) and other solid tumors. Closest direct comparable given similar PDC/radioconjugate approach and clinical-stage pipeline.

Broad incumbents

• Lantheus Holdings: Established radiopharmaceutical company with commercial portfolio including diagnostic imaging agents (e.g., DEFINITY, Neuraceq) and therapeutic radiopharmaceuticals (PNT2002). Larger incumbent serving overlapping oncology radiopharmacy channels.
• Novartis: Major pharma with Pluvicto (lutetium-177 PSMA-617) and Lutathera radioligand therapies for prostate cancer and neuroendocrine tumors. Sets the commercial benchmark and competitive context for targeted radiopharmaceutical therapies.
• Bayer: Developer of Xofigo (radium-223) for metastatic castration-resistant prostate cancer and active investor/developer in radiopharmaceuticals through acquisitions including Algeta and Noria Therapeutics.
• Bristol-Myers Squibb: Major oncology company with RayzeBio acquisition ($4.1B) bringing actinium-225 based radiopharmaceutical platform targeting solid tumors. Represents a key strategic competitor in alpha-emitter oncology space.
• Eli Lilly: Acquired POINT Biopharma for $1.4B in late 2023, adding a pipeline of radioligand therapies including PNT2002 for prostate cancer. Active participant in commercial-stage radiopharmaceutical market development.
• AstraZeneca: Major oncology company that acquired Fusion Pharmaceuticals in 2024 for actinium-225 based alpha-emitter radioconjugate platform. Active strategic entrant into targeted radiopharmaceutical oncology space.

Emerging players

• Fusion Pharmaceuticals: Clinical-stage biotech developing targeted alpha therapies using actinium-225 conjugates for solid tumors (acquired by AstraZeneca in 2024 for $2.4B). Direct comparable in alpha-emitter oncology development approach.
• ITM Isotope Technologies: European radiopharmaceutical company developing therapeutic and diagnostic radionuclides including Lu-177, Ac-225, and Y-90 based targeted therapies. Comparable platform approach targeting oncology indications.
• Ariceum Therapeutics: Private clinical-stage radiopharmaceutical company developing targeted radionuclide therapies for cancers including SSTR2-expressing tumors. Compares to Cellectar as a similarly staged targeted radionuclide company.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat3 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/cellectarbio
• YouTubeyoutube.com/@cellectarbiosciences5503
• Facebookfacebook.com/cellectarbiosciences
• LinkedInlinkedin.com/company/cellectar-biosciences-inc
• Instagraminstagram.com/cellectarbio

Compliance5 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles9 records

Funding overview

Funding rounds16 records

Investors17 records

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

M&A1 record

Investments

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

Frequently asked questions about Cellectar Biosciences