Koschmieder, Steffen

Abstract Most myelofibrosis (MF) drug approvals by Health Authorities are based on 1 or 2 outcome measures such as spleen volume reduction and/or improved quality-of-life. This 1–2 dimensional approach fails to capture the clinical complexity of MF. A European LeukemiaNet (ELN) taskforce developed a composite endpoint which allows multiple outcomes to be simultaneously measured. The panel used the Desirability-Of-Outcome-Ranking (DOOR) method to assign 25 outcomes into 4 quartiles based on a multi-dimensional desirability score and build a 5-layer composite outcome named Desirability-of-Myelofibrosis-Outcomes (DEMYO). Outcome operational definitions were tested by Delphi consensus and correlations with survival validated by a literature review. The outcomes assigned to the first two quartiles were negatively correlated with leukemia-free survival and survival. DEMYO comprehensively captures relevant MF clinical features and meaningful endpoints. Despite DEMYO requires validation based on available trial data, it is expected to improve the quality of Health Authority approvals for new drugs for MF.

Abstract With emerging new drugs in myelofibrosis (MF), a robust and harmonized framework for defining the severity of anemia and response to treatment will enhance clinical investigation and facilitate interstudy comparisons. Accordingly, the lead authors on the 2013 edition of the International Working Group–European LeukemiaNet (IWG-ELN) response criteria in MF were summoned to revise their document with the intent to (1) account for gender-specific differences in determining hemoglobin levels for eligibility criteria; (2) revise the definition of transfusion-dependent anemia (TDA) based on current restrictive transfusion practices; and (3) provide a structurally simple and easy to apply response criteria that are sensitive enough to detect efficacy signals (minor response) and also account for major responses. The initial draft of the 2024 IWG-ELN proposed criteria was subsequently circulated around a wider group of international experts and their feedback incorporated. The proposed articles include new definitions for TDA (≥3 units in the 12 weeks before study enrollment) and hemoglobin thresholds for eligibility criteria (<10 g/dL for women and <11 g/dL for men). The revised document also provides separate (TDA vs non-TDA) and graded (major vs minor response) response criteria while preserving the requirement for a 12-week period of screening and observation on treatment.

SummaryThe randomized, double‐blind, double‐dummy, phase 3b RELIEF trial evaluated polycythaemia vera (PV)‐related symptoms in patients who were well controlled with a stable dose of hydroxycarbamide (also termed hydroxyurea) but reported PV‐related symptoms. Patients were randomized 1:1 to ruxolitinib 10 mg BID (n = 54) or hydroxycarbamide (prerandomization dose/schedule; n = 56); crossover to ruxolitinib was permitted after Week 16. The primary endpoint, ≥50% improvement from baseline in myeloproliferative neoplasm ‐symptom assessment form total symptom score cytokine symptom cluster (TSS‐C; sum of tiredness, itching, muscle aches, night sweats, and sweats while awake) at Week 16, was achieved by 43·4% vs. 29·6% of ruxolitinib‐ and hydroxycarbamide‐treated patients, respectively (odds ratio, 1·82; 95% confidence interval, 0·82–4·04; P = 0·139). The primary endpoint was achieved by 34% of a subgroup who maintained their hydroxycarbamide dose from baseline to Weeks 13–16. In a post hoc analysis, the primary endpoint was achieved by more patients with stable screening‐to‐baseline TSS‐C scores (ratio ≤ 2) receiving ruxolitinib than hydroxycarbamide (47·4% vs. 25·0%; P = 0·0346). Ruxolitinib treatment after unblinding was associated with continued symptom score improvements. Adverse events were primarily grades 1/2 with no unexpected safety signals. Ruxolitinib was associated with a nonsignificant trend towards improved PV‐related symptoms versus hydroxycarbamide, although an unexpectedly large proportion of patients who maintained their hydroxycarbamide dose reported symptom improvement.