Salvage Treatment with Ofatumumab and ESHAP (O-ESHAP) for Patients with Relapsed or Refractory Classical Hodgkin's Lymphoma After First-Line Chemotherapy: Interim Analysis of a Phase II Trial of the Spanish Group of Lymphoma and Bone Marrow Transplantation (GELTAMO)

Abstract 1630

The management of recurrent or refractory Hodgkin's lymphoma (HL) remains challenging. Previous published data have suggested that infiltrating normal B lymphocytes in classic HL lesions may contribute to the survival of Hodgkin and Reed-Sternberg cells in vivo. The objective of this prospective, multicenter, phase II trial was to investigate the activity of an anti-CD20 monoclonal antibody, ofatumumab, in combination to a standard platinum-based salvage regimen, ESHAP (O-ESHAP) followed by high-dose chemotherapy and autologous stem cell transplantation (ASCT) for patients with classical HL failing to first line chemotherapy. Forty- five patients (25 M / 21 F, median age 34 years, range 18–66) were enrolled in the study between June 2010 and June 2012. Treatment consisted on three cycles of ESHAP plus ofatumumab 1,000 mg days 1 and 8 on first cycle and day 1 on second and third cycles. At the time of study entry, 66% of patients had III-IV Ann Arbor stage, 16% bulky disease, 18% B symptoms, 40% extranodal HL and 52% ≥3 involved nodal areas. We respect to response to first-line therapy, 46% patients had achieved a completed response (CR) and then relapsed, 6% had a partial remission (PR), whereas the remaining 48% were primary refractory. Eighty-one percent patients have received 3 cycles of O-ESHAP as scheduled, three patients 2, and five 1 cycle (1 patient due to toxicity, 1 patient's decision, 2 HL progression, and 4 treatments ongoing). Grade 3–4 WHO hematological toxicity was observed in 16%, 19%, and 20% after cycles 1, 2, and 3, respectively. Non-hematological toxicity was reported in 32%, 10%, and 20%, respectively. Overall response (OR) rate was 63% (49% CR and 14% PR). Response to O-ESHAP according to prior response to first-line chemotherapy is shown in table 1. Adequate PBSCs collection was achieved in 94% mobilized patients. Twenty-six out of 33 patients have already proceeded to ASCT. Two patients died of neutropenic sepsis after ASCT and HL progression, respectively. Preliminary results of this ongoing trial suggest that addition of ofatumumab to ESHAP is safe and has a promising clinical activity in patients with relapsed/refractory HL candidates to ASCT.