Long-Term Clinical Outcomes of Tisagenlecleucel in Pediatric and Young Adult Patients With Relapsed/Refractory ALL

We report the 5-year analysis of tisagenlecleucel in 79 pediatric and young adult patients with relapsed or refractory (r/r) B-cell ALL (B-ALL) from the global phase II ELIANA trial (ClinicalTrials.gov identifier: NCT02435849), with a median follow-up of 79.4 months. Tisagenlecleucel was administered as a single infusion with dosing normalized by weight in patients ≤50 kg. Key long-term end points included relapse-free survival (RFS), overall survival (OS), and safety. Censoring included loss to follow-up, withdrawal of consent, new anticancer therapy (± stem cell transplantation [SCT]), and death. The estimated 5-year RFS among responders (n = 70) with and without inclusion of SCT in censoring for new anticancer therapies was 47.3% and 51.0%, respectively. The median time to B-cell recovery was not reached with censoring for all further anticancer therapies, including SCT. The median OS was not reached. The estimated OS at 5 years was 55.0% and 62.4% with and without inclusion of SCT in censoring for new anticancer therapies, respectively. In total, 17 responders received a postinfusion SCT, 14 while still in complete remission. No new or unexpected adverse events were reported. These findings continue to support the potential of tisagenlecleucel as definitive therapy for many heavily pretreated pediatric and young adult patients with r/r B-ALL.