Cost effectiveness (CE) of blinatumomab (BLIN) versus inotuzumab ozogamicin (INO) in adult patients with relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) with no more than one prior salvage therapy (S0/S1) from a United Kingdom health care perspective.

Abstract

e18359 Background: To estimate Incremental CE Ratio (ICER) of BLIN vs INO in adults with R/R S0/S1 ALL based on matching-adjusted indirect comparison (MAIC) of TOWER and INO-VATE trials from a UK healthcare perspective. Methods: CE was estimated by a partitioned-survival model with outcomes based on published aggregate data from INO-VATE (cutoff: 01/05/2017) and individual patient data from TOWER weighted to match patients in INO-VATE using MAIC. Five analyses were conducted based on alternative approach for the MAIC (anchored through Standard of Care [SOC] vs unanchored), proportional hazard (PH) assumptions, and reference overall survival (OS) distributions. Rates of complete remission and HSCT, utilities, duration of therapy, and use of subsequent therapies also were MAIC adjusted. Due to inconsistent definitions of event-free survival (EFS) between the trials, EFS was assumed to be equal for BLIN and INO complete responders. Costs were estimated from published sources and included those of medicine and administration, key adverse events, HSCT, salvage therapy, and terminal care. Utilities were based on EORTC-8D values derived from EORTC QLQ-C30 assessments in TOWER. A 50-year time horizon was used. Results: In all analyses, BLIN was more costly and more effective than INO. The ICER for BLIN vs INO ranged from £4,014 to £13,371 per QALY. Conclusions: For various approaches for conducting MAIC of BLIN vs INO, BLIN was highly cost effective vs INO in R/R ALL adults with S0/S1 from a UK healthcare perspective. [Table: see text]