Burixafor Phase 2 Trial in Multiple Myeloma Nears Key Clinical Readout

Exicure's ongoing Phase 2 study (NCT05561751) is a randomized, open-label, multicenter trial evaluating burixafor, a small molecule CXCR4 antagonist, in autologous stem cell transplant (ASCT) for multiple myeloma. By blocking CXCR4, burixafor is designed to mobilize hematopoietic stem cells out of the bone marrow and into the bloodstream, where they can be collected for use in transplant procedures.

Interim results to date have been highly encouraging, with 100% of patients (10/10) achieving the primary endpoint of successful CD34+ stem cell mobilization, including patients previously treated with daratumumab. Burixafor has a faster kinetics of mobilization with a well-tolerated safety profile, enabling same-day administration of the mobilizing agent and leukapheresis. This differentiates burixafor from FDA-approved agents such as plerixafor and motixafortide, which require overnight pre-treatment.

In August, the company announced that the final patient had completed their last study visit. The clinical database has since been locked, and Exicure remains on track to report topline data in Q4 2025. Preparations are also underway for a potential Phase 3 trial.

A full data publication from the ongoing Phase 2 trial (NCT05561751) is anticipated in 2026. In addition, a publication from a previous Phase 2 study (NCT02104427) evaluating burixafor in combination with G-CSF in patients with multiple myeloma, non-Hodgkin lymphoma, and Hodgkin disease, is currently under peer review.

Expanding Development Opportunities

Building on progress in multiple myeloma, Exicure is preparing to expand burixafor into additional indications:

• Sickle Cell Disease: Exicure is in discussions with key clinicians at leading institutions to initiate an investigator-sponsored trial evaluating burixafor for improving stem cell mobilization in patients undergoing gene editing and autologous transplant.
• Acute Myeloid Leukemia (AML): The company is also planning a Phase 1 chemosensitization study in AML. Preclinical data suggest that burixafor may mobilize tumor cells from protective bone marrow niches, potentially enhancing the efficacy of chemotherapy.

New Leadership Strengthen Scientific and Clinical Capabilities

Following its acquisition of GPCR Therapeutics USA earlier this year, Exicure has been advancing the Phase 2 trial with dedicated internal drug development experts. These scientific leaders bring broad experience spanning from basic research to regulatory approval and have decades of proven track records in developing innovative medicines.

Josephine (Pina) Cardarelli, Ph.D. joined as President and Chief Scientific Officer. Dr. Cardarelli is a seasoned drug development executive whose career spans oncology, immunology, pharmacology, and translational medicine. She most recently served as Vice President of Cell Biology & Pharmacology at Bristol-Myers Squibb, where she played a key role in the approvals of Yervoy® and Opdivo® and Fucosyl GM-1 antibody program that is currently in Phase 3. Earlier in her career at Medarex, she advanced multiple programs into clinical development, including CXCR4 (Ulocuplumab), CXCL10, CD30, and CD19 antibodies and multiple ADCs. She also identified the lead antibody for the IFNα receptor program that ultimately became AstraZeneca's FDA-approved Saphnelo™. With more than 100 global patents and over 50 peer-reviewed publications, Dr. Cardarelli brings extensive expertise in biologics, antibody-drug conjugates, IND strategy, and regulatory affairs. She received her Ph.D. in physiology from Albany Medical College.

Niña Caculitan, Ph.D. has been appointed Head of Clinical, overseeing activities spanning manufacturing, regulatory affairs, clinical development, clinical operations and data analysis. She brings over 15 years of experience from both academia and industry, with a strong background in antibody and small molecule chemistry for therapeutics in oncology and immune-mediated disorders. Previously, she was a key contributor to understanding cellular mechanisms of antibody drug conjugate processing at Genentech. Dr. Caculitan earned her Ph.D. in chemistry from the University of California, Berkeley.

Devki Sukhtankar, Ph.D. has joined as Head of Preclinical Research and Translational Medicine, guiding cross-functional translational research efforts with a focus on integrating clinical data and advancing the pipeline into new indications. She brings over 15 years of experience in oncology, neurology and inflammatory diseases, where she has led preclinical programs with a focus on pharmacology and contributed to 20 peer-reviewed publications. Dr. Sukhtankar earned her Ph.D. in cancer biology from the University of Arizona and has extensive experience collaborating with partner organizations to expand therapeutic opportunities.