[602] Successful Stem Cell Mobilization Rescue by AMD3100 (Plerixafor)+G-CSF for Patients Who Failed Primary Mobilization: Results from the Phase III (3101-NHL) Study. Session Type: Oral Session

Ivana Micallef, Patrick J. Stiff, John F. DiPersio, Richard Thomas Maziarz, John M. McCarty, Jennifer Angell, Gary Bridger, Gary Calandra, on behalf of the 3101 Investigators Mayo Clinic, Rochester, MN, USA; Loyola University, Chicago, IL, USA; Washington University, St. Louis, MO, USA; Oregon Health Science University, Portland, OR, USA; Virgina Commonwealth University Medical Center, Richmond, VA, USA; Genzyme Corporation, Cambridge, MA, USA

Background: AMD3100 (plerixafor)+G-CSF (A+G) was generally safe and more effective in mobilizing CD34+ hematopoietic stem cells compared to placebo+G-CSF (P+G) in a Phase III, multicenter, randomized, double-blind, placebo controlled study conducted in patients with non-Hodgkins lymphoma (NHL). In the intent-to-treat analysis, 78/148 (53%) patients in the P+G group and 20/150 (13%) patients in the A+G group failed to mobilize 2 x 10⁶ CD34+ cells/kg, p<0.0001. Of these failure patients, 52 in the P+G group and 10 in the A+G group consented to enter into the rescue arm of the study. This abstract reports the outcomes of these rescue patients. Methods: Patients enrolled in the Phase III study who failed to mobilize 2 x 10⁶ CD34+ cells/kg could enter into the rescue arm of the study and receive A+G. The patients treatment assignment in the study remained blinded. Following a rest period of 7 days, patients were given G (10 g/kg/day) subcutaneously (SQ) for 4 days. In the evening around 10PM on Day 4, patients were given a dose of A (240 g/kg SQ). On Day 5, all patients returned to clinic to receive a morning dose of G before apheresis. Patients continued to receive the evening dose of A followed by morning dose of G and apheresis the next day for up to a total of 4 aphereses or until 5 x 10⁶ CD34+ cells/kg were collected. Pooled cells were allowed for transplantation. Results: After rescue therapy, 33/52 (63%) patients who previously failed P+G and 4/10 (40%) patients who previously failed A+G collected 2 x 10⁶ CD34+ cells/kg. Seven of the 33 patients who previously failed with P+G collected 5 x 10⁶ CD34+ cells/kg. Six of the ten A+G patients and 46/52 P+G patients were transplanted. Median time to PMN engraftment was Day 10 and Day 11 for the A+G and P+G groups, respectively. Median time to platelet engraftment was Day 22 and Day 20 for the A+G and P+G groups, respectively. One patient in the P+G group never had platelet counts > 50,000 and was counted as a failure to engraft, even though the patient was clinically stable through 6 months post-transplant. In the re-mobilized group, 9 patients died (2 patients were never transplanted and 7 patients had disease progression). Grafts were durable for 100 days in all 6 rescued A+G patients and all 41 rescued P+G patients who engrafted. The predominant adverse events were mild gastrointestinal effects (diarrhea, nausea, vomiting, and abdominal pain) and injection site reactions. There were no drug-related serious adverse events reported in these re-mobilized patients. Conclusions: The addition of AMD3100 to G-CSF successfully mobilized sufficient stem cells for transplant in 63% of NHL patients who previously failed mobilization with G-CSF alone. The high success rate is consistent with the Compassionate Use Protocol experience. AMD3100 was generally well tolerated. The 40% success rate in the patients who previously failed AMD3100+G-CSF suggests that re-mobilization with the same combination is a potentially useful strategy for similar patients.
Abstract #602 appears in Blood, Volume 110, issue 11, November 16, 2007
Keywords: AMD3100|Non-Hodgkin Lymphoma|Mobilization
Disclosure: Research Funding: Genzyme Corporation.

Monday, December 10, 2007 3:45 PM

Session Info:  Simultaneous Session: Autologous Transplantation: Clinical Results (3:30 p.m.-5:00 p.m.)