Autologous stem cell transplantation is indicated for patients with HD who have primary refractory disease or who relapse after a first remission. For these patients, as for other patients undergoing autologous transplantation, the number of CD34+ cells infused is a reliable predictor of neutrophil and platelet engraftment, and doses ≥ 5 x 106 CD34+ cells/kg are associated with faster count recovery. However, among the 98 patients with HD who have undergone G-CSF-alone mobilization at our institution in the past five years, 22% did not achieve a minimum HPC collection of 2 x 106 CD34+ cells/kg in ≤ 5 apheresis procedures, and only 15% achieved a collection ≥ 5 x 106 CD34+ cells/kg. AMD3100 mobilizes HPCs by reversibly inhibiting the interaction of CXCR4 and SDF-1α. It has been shown to improve HPC mobilization in patients with multiple myeloma and non-Hodgkin’s lymphoma. Here we present results for the first ten HD patients treated with a mobilization regimen of AMD3100 + G-CSF. To date, ten patients with relapsed (8) or refractory (2) HD have been mobilized with G-CSF (10 ug/kg/d) + AMD3100 (240 ug/kg/d) beginning on day 4. Apheresis was performed 11 hours after each AMD3100 dose. The first dose of AMD3100 produced a median (range) 3.0 (1.9–5.1) fold increase in the number of circulating CD34+ cells. Six patients (60%) achieved a collection of ≥ 5 x 106 CD34+ cells/kg, and all patients collected > 2 x 106 CD34+ cells/kg (range, 3.6–9.4 x 106 CD34+ cells/kg). The median (range) number of apheresis procedures performed per patient was 2 (1–4). No grade II-IV adverse events were ascribed to AMD3100. Eight patients have been transplanted with G-CSF + AMD3100 mobilized cells. All have had prompt and stable engraftment, with median neutrophil recovery at day +9 (9–11) and median platelet recovery at day +20 (15–23). Two patients had very early engraftment, with absolute neutrophil count greater than 100 on day +7. We conclude that AMD3100 + G-CSF is a well-tolerated and effective mobilization regimen in patients with HD. All patients (100%, 95% CI 69%-100%) mobilized with AMD3100 + G-CSF achieved the minimum collection of 2 x 106 CD34+ cells/kg, and a significantly higher proportion of patients (60%, 95% CI 26%–88%) achieved the goal collection of ≥ 5 x 106 CD34+ cells/kg than did the historical controls (15%). Importantly, the median collection in the first two days of pheresis was 5.4 x 106 CD34+ cells/kg, which is significantly better than historical controls, who collected a median 3.0 x 106 CD34+ cells/kg in the first two days of pheresis (p=0.014). Our results demonstrate that the mobilization regimen of AMD3100 + G-CSF can improve the number of HPCs collected and decrease the number of days of pheresis in HD patients. This regimen will be pursued further in this patient population.