Hospitalization for patients in the United States (US) and European Union (EU) treated with inotuzumab ozogamicin (InO) vs standard of care (SOC) for relapsed/refractory acute lymphoblastic leukemia (R/R ALL) in a global phase 3 trial.

Abstract

e18500 Background: InO, an anti-CD22 antibody-calicheamicin conjugate, with its once a week, 1-hour infusion schedule, has demonstrated lower hospital utilization in association with superior clinical activity, favorable patient-reported outcomes (PROs), and a generally manageable safety profile versus SOC (intensive chemotherapy) for R/R ALL in the phase 3 INO-VATE trial. Here, regional-specific hospitalizations in the trial are presented. Methods: Patients receiving study treatment and recruited from the US and the EU were included in the analyses. The total number of days hospitalized for each patient was calculated. Hospital days prior to randomization and those after the end of study treatment were excluded. Due to different treatment durations for InO and SOC (median 1 vs 3 cycles), calculations were reported for cycle 1 treatment period (randomization to end of cycle 1) and for the entire treatment period (all cycles - randomization to end of treatment). Results: A total of 281 patients were available for the analyses. 154 were from the US and 127 from 11 of the EU countries. The median and mean hospitalization days were shorter for patients in the InO arm compared to the SOC arm across both regions (Table). The difference between the two treatment arms appear to be greater in the US compared to the EU. Hospitalizations in the US appear to be shorter than in the EU, particularly for patients receiving InO. Conclusions: InO treatment in R/R ALL is associated with less hospitalization across both the US and EU compared to SOC, consistent with InO’s better efficacy, tolerability, PRO and dosing schedule. The finding that US has lower hospitalization than the EU might be explained by different patient care practices in the two regions. Given that hospitalization is the biggest cost driver in cancer care, the discrepancy may lead to greater cost-savings in healthcare systems where hospitalizations are strictly managed. Clinical trial information: NCT01564784. [Table: see text]