Stem-Cell Mobilization Booster Wins FDA Approval for Multiple Myeloma

The FDA has approved the CXCR4 antagonist motixafortide (Aphexda) for use with filgrastim (Neupogen) to mobilize stem cells for autologous transplantation in multiple myeloma, BioLineRx announced on Monday.

Recent advances in disease management have substantially increased use of autologous stem cell transplantation for multiple myeloma. The success rate depends on effective mobilization of peripheral stem cells to obtain an adequate cell harvest, the company said.

“Achieving target-collection goals can be difficult in some patients given modern barriers, including the treatment of older patients and use of contemporary induction regimens,” said John DiPersio, MD, PhD, of Washington University in St. Louis, in the company statement. “Innovation in this area of medicine has been needed and today’s approval of Aphexda addresses the demand for new therapies that can meet today’s challenges by delivering more reliability in stem cell mobilization, versus filgrastim alone, with fewer days of apheresis sessions and fewer doses of filgrastim for people living with this cancer.”

Primary support for the approval came from the phase III GENESIS trial that compared filgrastim plus motixafortide or placebo for stem-cell mobilization prior to autologous transplantation in 134 patients with multiple myeloma (2:1 randomization).

The results showed that motixafortide plus filgrastim led to achievement of the stem-cell goal of ≥6 × 10⁶ CD34+ cells/kg within two apheresis sessions in 67.5% of patients as compared with 9.5% of the placebo group, as assessed by a central laboratory. Assessment by local laboratories showed that 92.5% of patients met the goal with motixafortide versus 21.4% with placebo.

A safety analysis showed that serious adverse events occurred in 5.4% of patients treated with motixafortide, including vomiting, injection-site reactions, hypersensitivity reactions, injection-site cellulitis, hypokalemia, and hypoxia. The most common adverse events (≥20% of patients) were injection-site reactions, pruritus, flushing, and back pain.