Cellectar secures $140 million to advance pivotal cancer therapy

Cellectar Biosciences Inc. is moving to secure its position in the targeted cancer therapy market, announcing positive 12-month data for its lead drug candidate, iopofosine I 131, and securing up to $140 million in financing to advance the program toward U.S. regulatory submission.

“The first part of 2026 was a pivotal period for Cellectar as we executed across our pipeline and capital strategies to position the company for value creation,” said James Caruso, president and chief executive officer of Cellectar. “The recently reported positive 12-month follow-on data from our CLOVER WaM study reinforce our confidence that iopofosine can provide meaningful patient benefits and meet regulatory expectations.”

The financing provides the necessary resources to initiate a Phase 3 confirmatory study for iopofosine I 131 in relapsed or refractory Waldenström Macroglobulinemia (r/r WM) and subsequently file for accelerated approval with the U.S. Food and Drug Administration. For the first quarter ended March 31, 2026, the company reported a net loss of $5.7 million, or $1.33 per share, on research and development expenses of $3.0 million.

The successful data and financing round are critical for Cellectar’s proprietary Phospholipid Drug Conjugate (PDC) platform, which aims to deliver radioisotopes like iodine-131 directly to cancer cells, sparing healthy tissue. This approach could offer a new treatment paradigm for patients who have exhausted other options, including BTK inhibitors, and provides a foundation for the company’s broader radiopharmaceutical pipeline.

Iopofosine Data and Path to Approval

The positive results came from the CLOVER-WaM Phase 2b study, which evaluated iopofosine in r/r WM, a rare and incurable type of non-Hodgkin's lymphoma. The 12-month follow-on data reinforced the drug's potential to provide a durable response in a patient population with high unmet medical need. With the new capital, Cellectar plans to launch a confirmatory study to support a filing for accelerated approval, a pathway intended for drugs that treat serious conditions and fill an unmet medical need based on a surrogate endpoint.

Iopofosine I 131 has already received multiple designations from the FDA, including Breakthrough, Orphan Drug, Rare Pediatric Drug, and Fast Track, highlighting its potential significance across various cancer indications.

Expanding the PDC Pipeline

Beyond its lead program, Cellectar is advancing a broader pipeline based on its PDC technology. The company recently dosed the first patients in a Phase 1b study of CLR 125, which uses iodine-125, in triple-negative breast cancer, with initial data expected in mid-2026. This expands the platform's application into solid tumors.

The company is also developing CLR 225, which utilizes the potent alpha-emitter actinium-225, for solid tumors like pancreatic cancer. The progress across multiple candidates shows the modularity of the PDC platform, which can be paired with different radioisotopes to target a variety of cancers. For the first quarter, the company's research and development expenses fell to $3.0 million from $3.4 million in the prior-year period.

This article is for informational purposes only and does not constitute investment advice.