Dynamic Frailty Assessment in Transplant Non-Eligible Newly Diagnosed Myeloma Patients: Initial Data from UK Myeloma Research Alliance (UK-MRA) Myeloma XIV (FiTNEss): A Frailty-Adjusted Therapy Study

Background Multiple myeloma (MM) is a blood cancer that predominates in the older adult with significant morbidity and mortality. Frailty is increasingly recognized as a predictor for long- and short-term outcomes, with those who are frailer at risk of greater toxicity, treatment discontinuation and poorer survival. Identifying and tailoring treatment for frail older patients with MM remains an unmet need. The International Myeloma Working Group frailty score (IMWG FS) is a prognostic biomarker for survival, but no evidence exists for its predictive biomarker potential. In addition, defining frailty at a single timepoint (baseline) by the IMWG FS may mask disease overlay and the improvements seen with therapy delivery. Understanding both improvements and deteriorations in frailty during treatment may have important implications for dynamic treatment delivery. Study Design and Methods The UKMRA Myeloma XIV FiTNEss trial (NCT03720041) is a phase III, multi-centre, randomised controlled trial for newly diagnosed patients with MM ineligible for a stem cell transplant. The primary objectives of the study are 1) to compare early treatment cessation (within 60 days of randomisation) between patients randomised to standard (reactive) and frailty-adjusted (adaptive, based on IMWG FS) induction therapy delivery with the triplet ixazomib, lenalidomide and dexamethasone (IRd) and 2) to compare progression-free survival for maintenance lenalidomide (R) and lenalidomide plus ixazomib (IR). Baseline revised IMWG FS (considering only those scoring >=3 frail) and UKMRA Myeloma Risk Profile (MRP) were determined. Here we report the changes in IMWG FS for the patients recruited to the standard (toxicity-reactive) arm, including demographic data and the identification of an ultra-frail group. Results The FiTNEss trial opened on 04/08/2020 and at the time of data cut off (01/06/2023) recruitment is active at 84 sites, with 638 patients randomised. Baseline characteristics for the randomised patients are shown in Table 1. The median age of patients is 76 years (range 62, 93) with 34.8% aged 76-80 and 22.3% over 80. The IMWG FS at baseline for the full trial cohort was FIT 182/638 (28.5%), UNFIT 207/638 (32.4%) and FRAIL 249/638 (39.0%). Revised IMWG FS at baseline was Fit 28.5%, Unfit 56.0% and Frail 15.5% with MRP non-high risk (Fit or Unfit, nHR) in 64.3% and MRP HR (Frail) in 35.7% in patients with data available. For descriptive analysis of FS dynamism, we assessed the impa