Cellectar Biosciences and Orano Med, two companies using distinct strategies to develop innovative therapies for cancer, are joining forces to advance a class of anti-cancer therapies called phospholipid drug conjugates. Phospholipid drug conjugates (PDC) are a cancer therapy that explores the tumor-targeting properties of lipid (fat) molecules to selectively deliver radiation to malignant cells, with the intention of minimizing radiation exposure to normal tissue. The new PDC molecules will combine Cellectar’s phospholipid ether (PLE), which targets tumor cells with high specificity, and Orano’s unique alpha emitter, lead-212 (212Pb). Once inside cells, 212Pb causes DNA molecules to break, leading to cancer cell death. The companies plan to evaluate the new PDC in up to three types of cancer. “We believe that the combination of Cellectar’s targeted delivery with Orano Med’s powerful alpha emitter offers the potential to create a novel and highly potent cancer therapy,” James Caruso, CEO of Cellectar Biosciences, said in a press release. “This collaboration is an ideal strategic fit and provides an excellent opportunity to expand our radiotherapeutic portfolio beyond CLR 131, a highly potent beta emitter, and establish one of the most complete oncology-focused radiotherapeutic portfolios." PDCs are a long-known therapeutic strategy among the medical community. One established example is Cellectar’s CLR 131, a PDC that targets cancer cells by lipid (fat) affinity and delivers the toxic radioisotope iodine-131 directly into the cells. CLR 131 has been tested for the treatment of several different types of cancer, including multiple myeloma and lymphoma. Recently, this investigational medicine was seen to significantly reduce tumor size of patients with diffuse large B-cell lymphoma (DLBCL) in a Phase 2 clinical trial (NCT02952508). Despite CLR 131's success, Orano's radioactive substance may have a greater efficacy than iodine-131. The compound delivers high energy particles over a shorter distance than other radioactive molecules, enabling the use of lower doses and reducing side effects on surrounding cells. Based on this, Cellectar and Orano believe that a molecule made up of PLE and 212Pb may be an effective treatment for multiple cancer types. “This collaboration with Cellectar is an exciting opportunity for Orano Med. Our 212Pb is a powerful radioactive isotope that at low doses kill cancer cells and has limited impact on nearby healthy cells,” said Julien Dodet, CEO of Orano. “We believe that 212Pb conjugated to Cellectar’s PLE has great potential to improve patient outcomes by having a better efficacy and safety profile than other technologies.” The companies have agreed to equally share the preclinical costs of the clinical developmental program, with both parties having an option to advance and commercialize the PDC alone or as a team. This option becomes available after early proof-of-concept data is established. Orano is also collaborating with other companies to develop a broad pipeline of tumor targeting therapies using the 212Pb molecule bound to other biological molecules, including antibodies and peptides.