Patient-reported outcomes (PROs) with ibrutinib-rituximab in Waldenström macroglobulinemia (WM): Results from iNNOVATE.

Abstract

8018 Background: Anemia and fatigue can impair quality of life in patients (pts) with WM. Ibrutinib (ibr) as single agent or in combination with RTX is FDA-approved for WM. In pts with RTX-refractory WM, single-agent ibr induced meaningful improvements in PROs (Trotman, EHA 2017). In iNNOVATE, ibr-RTX (IR) produced higher rates of sustained hemoglobin improvement and meaningful improvements in PROs versus placebo-RTX (R; Dimopoulos NEJM 2018). Here, we report detailed PRO analyses from iNNOVATE. Methods: Pts with symptomatic WM requiring therapy were randomized to daily 420 mg oral ibr or placebo, both with RTX (375 mg/m2/week IV at weeks 1–4 and 17–20). PRO measures included FACIT-Fatigue (FACIT-F), FACT-An total score (TS) and anemia subscale score (AS), and EQ-5D-5L (EuroQol Research Foundation. EQ-5D is a trade mark of the EuroQol Research Foundation) visual analog scale (VAS), and utility score (US). Results: For 150 randomized pts (n=75/arm), most common reasons for initiating therapy were fatigue (61%), constitutional symptoms (32%), and anemia (32%). Baseline PRO scores were comparable in both arms. At a median follow-up of 26.5 mo, numerically more pts showed clinically meaningful improvement in FACIT-F, TS, and AS with IR than R (Table). Median time to PRO improvement was short (1-2 mo) in both arms. At week 25, the Pearson correlation coefficients were 0.28, 0.29, and 0.26 for changes in hemoglobin levels vs changes in FACIT-F, TS and AS, respectively, in the IR arm; no meaningful correlations were observed on R. The correlation coefficients were -0.32, -0.33, -0.35 and -0.26 for changes in IgM levels vs changes in FACIT-F, TS, AS, and EQ-VAS, respectively, for IR and 0.29 and 0.35 vs FACIT-F and TS for R. Conclusions: Clinical response and improvements in anemia with IR are consistent with more pts showing clinically meaningful improvement in PROs versus R. Changes in IgM correlate with improvements in PROs. Clinical trial information: NCT02165397. [Table: see text]