Cellectar Biosciences, Inc.

Cellectar Biosciences, Inc. is a late-stage clinical biopharmaceutical company focused on the discovery, development and commercialization of drugs for the treatment of cancer, leveraging its proprietary phospholipid ether drug conjugate (PDC) delivery platform designed to specifically target cancer cells and deliver improved efficacy and better safety as a result of fewer off-target effects. The global market for cancer drugs reached $215 billion in annual sales (2026), and with a compound annual growth rate (CAGR) of 11.17% could reach $555 billion by 2035, according to a report dated December 2025 by Coherent Market Insights. The Company is primarily focused on the development of its radioconjugate PDC programs, also known as phospholipid radioconjugates or PRCs, designed to provide targeted delivery of a radioisotope directly to cancer cells, while limiting exposure to healthy cells.

The Company believes its PDC platform possesses the potential for the discovery and development of the next generation of cancer-targeting treatments, and it plans to develop PDCs both independently and through research and development collaborations. The Company's three lead programs are CLR 121125 (CLR 125), an iodine-125 Auger-emitting program; CLR 121225 (CLR 225), an actinium-225 based program; and iopofosine I 131, a beta-emitting iodine-131 based program. On June 4, 2025, the FDA granted Breakthrough Therapy Designation for iopofosine I 131 as a radioconjugate monotherapy for the treatment of relapsed/refractory Waldenstrom macroglobulinemia (r/r WM). On October 6, 2025, the Scientific Advice Working Party (SAWP) of the European Medicines Agency (EMA) advised that filing for a Conditional Marketing Authorization (CMA) for iopofosine I 131 as a treatment for post-Bruton Tyrosine Kinase inhibitor (BTKi) refractory patients with WM could be acceptable for a CMA.

The Company generates revenue through the development and potential commercialization of its product candidates, with no approved products currently generating revenue; its business model is centered on research and development activities funded primarily through sales of equity-based securities, and it relies on a collaborative outsourcing model for manufacturing and clinical research. The Company's primary customer segments are patients with relapsed/refractory hematologic and solid tumor cancers, and it targets orphan-designated indications with significant unmet medical need.

Iopofosine I 131 is the Company's lead beta-emitting PRC, studied in the CLOVER WaM Phase 2 study in patients with r/r WM, where it met its primary endpoint with a major response rate (MRR) of 58.2% ¹ (95% confidence interval [44.50%, 75.80%, two-sided p value < 0.0001]) exceeding the FDA agreed-upon statistical hurdle of 20% ², and the overall response rate (ORR) in evaluable patients was 83.6% ³, with 98.2% ⁴ of patients experiencing disease control. The CLOVER WaM study enrolled a total of 55 ⁵ patients in the modified Intent to Treat (mITT) population, and iopofosine I 131 monotherapy achieved a 7.3% ⁶ complete remission (CR) rate in this highly refractory WM population. The CLOVER-1 Phase 2 study met the primary efficacy endpoints from the Part A dose-finding portion, conducted in r/r B-cell malignancies, and the Phase 2b study evaluated highly refractory MM patients in triple class, quad- and penta-drug refractory patients, including post-BCMA immunotherapy patients and r/r CNSL patients. CLR 121125 is an Auger-emitting PRC utilizing iodine-125, observed to show tolerability with minimal toxicities in animal models and good activity in multiple solid tumor models, especially in triple negative breast cancer, and is the subject of a Phase 1b dose finding study. CLR 121225 is an alpha-emitting, actinium-225 based PRC that has shown activity in multiple solid tumor animal models including pancreatic, colorectal and breast cancers, and the Company is currently prepared to initiate a Phase 1 imaging and dose escalation safety study subject to its ability to obtain additional financing.

The Company has also developed a series of proprietary small molecule phospholipid drug conjugates, and in collaboration with other parties, has validated that the PLE is capable of delivering peptide payloads and oligonucleotide (siRNA, mRNA, etc.) payloads to tumors when delivered systemically. The Company is also evaluating other alpha-emitting isotopes such as astatine-211 and lead-212 in preclinical studies. The Company's PDC platform is designed to provide selective delivery of a diverse range of oncologic payloads to cancerous cells, whether a hematologic cancer or solid tumor; a primary tumor, or a metastatic tumor; and cancer stem cells.

On April 30, 2025, the Company announced that it will explore a full range of strategic alternatives to advance its platform and radiopharmaceutical drug development pipeline. On June 24, 2025, the Company effected a 1-for-30 reverse stock split to regain compliance with the Nasdaq minimum bid price requirement. On July 2, 2025, the Company completed an underwritten public offering for gross proceeds of approximately $6.9 million ⁷, prior to deducting underwriting commissions and offering expenses. On October 7, 2025, the Company entered into warrant exercise inducement offer letters with certain holders of existing warrants, resulting in gross proceeds of approximately $5.8 million ⁸, prior to deducting placement agent fees and offering expenses. The Company also implemented a workforce reduction plan in December 2024 impacting approximately 60% ⁹ of employees, with a total expense charge of approximately $1,510,000 ¹⁰.

For the year ended December 31, 2025, the Company generated a net loss of approximately $21,791,037 ¹¹ and used approximately $23,118,217 ¹² in cash for operations. As of December 31, 2025, the Company had cash and cash equivalents of $13,196,033 ¹³, compared to $23,288,607 ¹⁴ as of December 31, 2024. Research and development expenses were approximately $11,498,761 ¹⁵ for 2025, compared to approximately $26,136,246 ¹⁶ for 2024. General and administrative expenses were approximately $11,481,083 ¹⁷ for 2025, compared to approximately $25,641,452 ¹⁸ in 2024. The Company had an accumulated deficit of approximately $269,133,500 ¹⁹ as of December 31, 2025.

The Company believes that it understands a path forward for potential accelerated and full approval of iopofosine I 131 based upon the CLOVER WaM study and the initiation of a comparator controlled Phase 3 confirmatory trial assessing progression free survival as the primary endpoints in WM patients. The submission for accelerated approval utilizing the CLOVER WaM study data can occur at the time of the initiation of Phase 3 randomized controlled confirmatory study and patient enrollment must be ongoing at the time of decision on the accelerated NDA. The confirmatory study will be executed in an earlier line of therapy than was tested in the CLOVER WaM patients, and the initiation of this study is dependent on funding. The Company plans to submit a New Drug Application (NDA) to the FDA for the accelerated approval of iopofosine I 131 as a treatment for WM once the confirmatory trial is underway, which is subject to sufficient funding.

The Company is focused on the development of CLR 121125, its Auger-emitting PRC, which is the subject of a Phase 1b dose finding study in triple negative breast cancer, with a maximum of 75 ²⁰ patients anticipated to be enrolled in the trial. The Company is also prepared to initiate a Phase 1 imaging and dose escalation safety study for CLR 121225, an alpha-emitting, actinium-225 based PRC, subject to additional funding. The Company is exploring options for the WM opportunity outside of the US market, which will seek to establish an arrangement with one or more biotechnology or pharmaceutical companies having strong product development and commercialization expertise and distribution infrastructure in Europe and parts of global markets. The Company has initiated a process that includes identifying a strategic partner with the resources to develop iopofosine I 131.

The Company's research and development expenses decreased by approximately $14,637,000 ²¹, or 56% ²², in 2025 compared to 2024, primarily due to a reduction in clinical project costs of approximately $6,876,000 ²³ and a decrease in manufacturing and related costs of approximately $6,362,000 ²⁴, driven by the conclusion of patient enrollment and declining patient follow-up for the WM clinical study, partially offset by increased activity in pre-clinical development project costs. General and administrative expenses decreased by $14,160,000 ²⁵, or 55% ²⁶, in 2025 compared to 2024, primarily driven by de-emphasizing pre-commercialization efforts and related personnel cost reductions.

The Company relies on a collaborative outsourcing model for supply of all its drug candidates and key components, sourcing each isotope and finished product through a decentralized and distributed network of contract manufacturers. In December 2025, the Company announced a multi-year supply agreement with Ionetix Corporation for two critical alpha-emitting radioisotopes: Actinium-225 (Ac-225) and Astatine-211 (At-21). The finished PRCs are currently supplied by either AtomVie or SpectronRx. The Company has successfully executed large scale production of iopofosine drug substance via a contract manufacturing organization that has been inspected and approved by the FDA and the EMA, and has observed 60-month ²⁷ stability for iopofosine drug substance in desiccated and refrigerated forms at small scale.

The Company's capital requirements are expected to be funded through the sale of equity and/or debt securities, a strategic transaction or other source of capital. As of the issuance date of the financial statements, the Company's available liquidity to fund operations over the next twelve months was limited to approximately $9.7 million ²⁸ of unrestricted cash and cash equivalents. Management plans to secure additional outside capital via the sale of equity and/or debt securities or execute a strategic transaction, and also plans to preserve liquidity, as needed, by implementing cost saving measures. The Company's research and development expenses were approximately $11,499,000 ²⁹ and $26,136,000 ³⁰ for 2025 and 2024, respectively.

The Company expects to continue to generate operating losses for the foreseeable future. As of December 31, 2025, the Company had an accumulated deficit of approximately $269,133,500 ³¹. The Company's ability to execute its current operating plan depends on its ability to obtain additional funding via the sale of equity and/or debt securities, a strategic transaction or other source of capital. The Company plans to continue actively pursuing financing alternatives, however, there can be no assurance that it will obtain the necessary funding, raising substantial doubt about the Company's ability to continue as a going concern within one year of the date these financial statements are issued.

The Company faces significant headwinds including the need for substantial additional capital to fund its operations and clinical development programs, with its cash balance of $13,196,033 ³² as of December 31, 2025, believed to be adequate to fund basic budgeted operations only into the third quarter of 2026. The Company's ability to continue development of iopofosine I 131 is dependent on identifying a strategic partner with the necessary resources or obtaining sufficient additional funding to initiate and at least partially enroll a confirmatory study. The Company also faces risks related to its reliance on third-party manufacturers and contract research organizations, and the uncertainty of obtaining regulatory approvals for its product candidates.

The Company's business may be adversely affected by political instability, disruption or destruction in a geographic region in which it operates, regardless of cause, including war, terrorism, riot, civil insurrection or social unrest, and natural or manmade disasters, including famine, flood, fire, earthquake, storm or pandemic events and spread of disease and the significant military action against Ukraine by Russia. The Company's internal computer systems, and those of its third-party manufacturers, contract research organizations and other third parties on which it relies, are vulnerable to damage from computer viruses, unauthorized access, cyber-attacks, phishing attempts, natural disasters, fire, terrorism, war and telecommunication and electrical failures.

The Company will require additional capital to continue its operations and may have difficulty raising additional capital; as of December 31, 2025, its consolidated cash balance was approximately $13.2 million ³³, which is believed to be adequate to fund basic budgeted operations only into the third quarter of 2026, and the Company has concluded that substantial doubt exists about its ability to continue as a going concern. The Company's success is dependent on the successful development of iopofosine for the treatment of hematologic or solid tumor cancers, and failure to complete development, obtain FDA approvals, or comply with ongoing governmental regulations could prevent, delay or limit introduction or sale of proposed products. The Company relies on a collaborative outsourced business model, and disruptions with third-party collaborators, including AtomVie and SpectronRx for drug product supply, may impede its ability to gain marketing approval and delay or impair commercialization. The Company's clinical studies may not demonstrate sufficient levels of efficacy necessary to obtain regulatory approvals, and results of earlier studies may not be predictive of future study results; for example, the CLOVER WaM study met its primary endpoint with an MRR of 58.2% ³⁴, but the Company still faces uncertainty regarding the confirmatory Phase 3 trial required for accelerated approval. The Company expects to rely on its patents and regulatory designations such as orphan drug classification, but these may not confer marketing exclusivity or other expected commercial benefits; the FDA has granted ODD for iopofosine for multiple indications, but orphan drug exclusivity may be limited if the Company seeks approval for an indication broader than the orphan-designated indication or if the FDA later determines the request for designation was materially defective.

Management's message emphasizes the Company's focus on leveraging its proprietary PDC platform to develop cancer-targeting treatments, with a core objective of developing PDCs designed to specifically target cancer cells and deliver improved efficacy and better safety. Key themes include the advancement of the three lead programs—CLR 121125, CLR 121225, and iopofosine I 131—and the strategic decision to explore a full range of strategic alternatives to advance the platform and pipeline. Management has emphasized the regulatory progress for iopofosine I 131, including the FDA's Breakthrough Therapy Designation and the EMA SAWP's advice that filing for a CMA could be acceptable, and has stated that the Company will likely require either a strategic partner with the necessary resources or sufficient additional funding to initiate and at least partially enroll a confirmatory study, which has been identified as a required predicate to the submission of an NDA to the FDA for the accelerated approval of iopofosine I 131 as a treatment for WM.