Cellectar Biosciences has been granted a U.S. patent for the method of use for the compounds CLR 131 and CLR 125 in the treatment of a broad range of cancers.
The new patent for CLR 131 — which is already being developed for the treatment of hematological cancers like multiple myeloma — is for a variety of solid cancers, including lung, breast, ovarian or cervical, prostate, adrenal, liver, colon, and subcutaneous cancers, as well as melanoma.
The two drugs are phospholipid drug conjugates (PDC), meaning they are composed of two different molecules bound together: a lipid molecule that selectively targets cancer cells and a radioactive compound.
Cellectar’s new patent comes in the wake of U.S. patents for the company’s phospholipid drug conjugate delivery platform in the same tumor types.
“This patent strengthens our radiotherapeutic intellectual property portfolio and further demonstrates Cellectar’s commitment to optimizing our PDC technology platform,” Jim Caruso, president and CEO of Cellectar, said in a news release.
“While we are currently focused on developing CLR 131 for hematologic malignancies such as multiple myeloma, the claims granted provide additional development optionality for Cellectar or a potential partner,” he said.
Cellectar’s lead candidate, CLR 131, is a PDC that delivers a radioactive compound, iodine-131, directly to tumor cells. It is currently being assessed in a variety of blood cancers, including in a Phase 1 trial for relapsed or refractory multiple myeloma patients (NCT02278315), and has shown benefits in patients’ overall response rates, progression-free survival, and quality of life.
This drug has been granted orphan drug status by the U.S. Food and Drug Administration (FDA) to treat multiple myeloma patients, and Cellectar believes it has the potential to be the first therapeutic agent to use phospholipids to target cancer cells.
CLR 125 is also a radiotherapeutic PDC, but it delivers radioactive iodine-125 to cancer cells instead of iodine-131. Preclinical studies have shown that this drug enters and is retained selectively in cancer cells.
In addition, in a project that was funded by a National Cancer Institute Fast-Track Small Business Innovation Research (SBIR) award, the company tested whether CLR 125 could be used to treat triple negative breast cancers when given either before or after surgery. Results showed the treatment is well tolerated by patients and induces a promising dose response, supporting further development of this drug.