FDG-PET Adapted Sequential Therapy With Brentuximab Vedotin and Augmented ICE Followed By Autologous Stem Cell Transplant For Relapsed and Refractory Hodgkin Lymphoma

Background Pre-transplant FDG-PET (PET) normalization is the strongest predictor of outcome following autologous stem cell transplant (ASCT) for patients with relapsed or refractory (rel/ref) Hodgkin lymphoma (HL) (Moskowitz, AJ. Blood. 2010 Dec 2;116(23):4934-7). Due to its high efficacy in ASCT failures, we aimed to determine whether brentuximab vedotin (BV) can replace ICE (ifosfamide, carboplatin, etoposide) salvage therapy, increase rate of PET normalization, and enhance referral to ASCT for patients (pts) who fail front-line HL therapy. Here we present our phase II study evaluating a novel salvage strategy for rel/ref HL, an intent-to-treat study of PET-adapted sequential therapy with BV and augmented ICE (augICE) prior to ASCT. Methods Patients with rel/ref HL who have failed 1 prior regimen are enrolling on this phase II clinical trial. Patients receive weekly brentuximab vedotin (BV) administered at 1.2mg/Kg IV weekly for 3 weeks on and 1 week off for 2 cycles, followed by PET. Patients who achieve normalization of PET (Deauville 2 or less) proceed to ASCT. Patients with PET scores of Deauville 3 or higher receive 2 cycles of augICE prior to consideration for ASCT. Results 41 of planned 46 patients have enrolled; 34 pts completed salvage therapy, of whom 33 proceeded to ASCT. 28 pts are at least 90 days post-ASCT and represent the focus of this report. These 28 pts include 20 (71%) males, 21 (75%) pts with primary refractory or relapse within 1 year of initial treatment, 11 (39%) with B symptoms at enrollment and 11 (39%) with extranodal disease. Median number CD34+ cells/kg collected were 7.44x 10^6 (2.96 - 31.43x10^6). Disease status prior to ASCT was CR (Deauville 2) for 27 pts and PR (Deauville 3) for 1 pt. Salvage therapy for pts in CR prior to ASCT include BV alone (9), BV followed by augICE (16), and BV followed by augICE (with Deauville 4 response) followed by involved field radiation to achieve CR (2). The 1 patient in PR prior to ASCT received BV followed by augICE. Conditioning regimens included BEAM (9), CBV( 9), and high dose chemoradiotherapy (10). Early (within 90 days) transplant-related toxicities include grade 2 pneumonitis (3pts) and grade 3 acute kidney injury (1pt); late toxicities include grade 3 esophageal stenosis (1pt), grade 3 acute kidney injury (1pt), and 1 death (7 months post ASCT) due to progressive multifocal leukoencephalopathy. After a median follow-up of 9.5 months post-ASCT (range 3.3-15.6 months), 2 of 28 pts have progressed (at 2.7 and 4.3 months post ASCT respectively). One achieved a second CR with BV and proceeded to allogeneic stem cell transplant (alloSCT); the second achieved near CR following GND (gemcitabine, vinorelbine, Doxil) and proceeded to alloSCT. Conclusion PET-adapted sequential salvage therapy with BV followed by augICE produces high CR rates, adequate stem cell collection, and facilitates referral to ASCT for virtually all pts. Updated results will be presented at the meeting. Disclosures: Moskowitz: Seattle Genetics: Research Funding. Off Label Use: Brentuximab vedotin is approved for treatment of Hodgkin lymphoma following failure of 2 multi-agent regimens or autologous stem cell transplant. This study is evaluating the use of brentuximab vedotin in the pre-transplant setting for Hodgkin lymphoma. Schoder: Seattle Genetics: Research Funding. Hamlin: Seattle Genetics : Consultancy, Honoraria. Horwitz: Millennium: Consultancy, Research Funding; Seattle Genetics, Inc.: Consultancy, Research Funding. Moskowitz: Seattle Genetics: Research Funding.