CXCR4 antagonist POL6326
POL6326 is a potent and selective antagonist of the chemokine receptor CXCR4. This reversible and competitive CXCR4 antagonist blocks the interaction with the ligand SDF-1 (stromal cell-derived factor 1) resulting in the mobilization of stem cells from the bone marrow into the circulating blood. This effect can be therapeutically used for stem cell transplantation where stem cells are collected from the blood by a procedure called apheresis and infused after chemotherapy to accelerate the reconstitution of the blood and the immune system. Furthermore, the principle of stem cell mobilization can also be applied to a wide range of indications involving tissue repair after injury. In this case, the stem cells are not collected, but migrate to the site of injury where they initiate and promote regeneration processes. In addition, in certain cancer types, e.g. leukemia, tumor cells can be mobilized by the same mechanism from their protective environment in tumor niches. Once in the circulating blood, these cells are more vulnerable to cancer chemotherapeutic drugs.
POL6326 has successfully completed Phase I clinical trials and is currently being investigated as a stand-alone therapy in a Phase II clinical trial for its efficacy in autologous transplantation of hematopoietic stem cells in multiple myeloma patients. Interim results of the Phase II trial reveal that POL6326 is safe and well tolerated by all enrolled patients. The interim results also show efficacy, in particular a rapid and predictable onset and a dose-dependent mobilization of stem cells. The mobilization, collection of stem cells from the circulating blood (apheresis), analysis and processing of stem cells is completed in one day which represents an important competitive advantage in the hospital compared to standard therapy.