Safety in both trials
“Very importantly, there were no deaths, there were no engraftment failures, there was no evidence of vector-mediated replication-competent lentivirus, and integration site analysis revealed no evidence of clonal dominance,” Dr. Olson said.
He added that most of the grade 3 or greater adverse events seen in both trials were directly attributable to busulfan-based myeloablative conditioning, including four episodes of veno-occlusive disease.
Nonhematologic grade 3 or higher adverse events in HGB-204 included stomatitis (n = 8), febrile neutropenia (n = 6), irregular menstruation (n = 3), pharyngeal inflammation (n = 2), and veno-occlusive liver disease (n = 1).
Nonhematologic grade 3 or higher adverse events in HGB-207 included stomatitis (n = 9), febrile neutropenia (n = 4), pharyngeal inflammation (n = 2), epistaxis (n = 3), pyrexia (n = 3), veno-occlusive liver disease (n = 3), ALT increase (n = 2), bilirubin increase (n = 2), and hypoxia (n = 2).
One patient in HGB-207 had grade 3 thrombocytopenia considered possibly related to LentiGlobin.
Dr. Olson reported advisory board engagement with bluebird bio, which sponsored both trials.
SOURCE: Olson TS et al. ASPHO 2019. Abstract 2002.