Verstovšek, Srđan

SummarySimtuzumab, a monoclonal antibody inhibitor of extracellular matrix enzyme lysyl oxidase‐like‐2, showed preclinical promise and was well tolerated in clinical studies. A phase 2, open‐label study of simtuzumab was conducted in patients with primary myelofibrosis (MF), post‐polycythaemia vera MF and post‐essential thrombocythaemia MF. Fifty‐four patients were randomized to receive simtuzumab alone (200 or 700 mg [n = 12 each group]) or simtuzumab (200 or 700 mg) with ruxolitinib (n = 15 each group) for 24 weeks. Simtuzumab alone or in combination with ruxolitinib showed no clinical benefit at 24 weeks. The mean serum simtuzumab trough concentrations appeared to increase dose‐proportionally between the 200‐mg and 700‐mg treatment groups. Therapy‐related serious adverse events were pyrexia, pain in extremity (both in 1 patient) and infusion reaction (in another patient). Bone marrow fibrosis (BMF) score was reduced at 24 weeks in 2 patients (16·7%) in the simtuzumab 700‐mg group, 1 (6·7%) in the simtuzumab 200‐mg + ruxolitinib group, and 2 (13·3%) in the simtuzumab 700‐mg + ruxolitinib group; similar numbers of patients had increased BMF. Simtuzumab alone or with ruxolitinib was well tolerated but did not produce clinical benefit nor consistently reduce BMF in patients with MF by 24 weeks.

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.

AbstractObjectivesPolycythemia vera (PV)‐related symptoms may not be adequately controlled with conventional therapy. This current analysis of the RESPONSE trial evaluated the effects of ruxolitinib compared with standard therapy on quality of life (QoL) and symptoms in patients with PV who were hydroxyurea resistant/intolerant.MethodsIn the previously reported primary analysis, ruxolitinib achieved the primary composite endpoint of hematocrit control and ≥35% reduction in spleen volume at Week 32. The current analysis evaluated patient‐reported outcomes using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire‐Core 30 (EORTC QLQ‐C30), the Myeloproliferative Neoplasm Symptom Assessment Form (MPN‐SAF), the Pruritus Symptom Impact Scale (PSIS), and the Patient Global Impression of Change (PGIC).ResultsCompared with standard therapy, ruxolitinib was associated with greater improvements in global health status/QoL, functional subscales, and individual symptom scores of the EORTC QLQ‐C30. At Week 32, more patients in the ruxolitinib arm (44%) achieved a ≥10‐point improvement in global health status/QoL vs. standard therapy (9%). Improvements in MPN‐SAF symptom scores were consistent with improvements in EORTC QLQ‐C30, PSIS, and PGIC scores.ConclusionsRuxolitinib provides clinically relevant improvements in QoL and ameliorates symptom burden in patients with PV who are hydroxyurea resistant/intolerant.

Key Points Treatment response criteria for MF must capture drug benefit in terms of symptom burden. The current document includes stricter definitions of red cell transfusion need and independence.

Key Points Evidence exists that ELN criteria for response in ET and PV issued in 2009 do not provide relevant measures of benefit for patients. Revised recommendations for assessing response are provided.

SummaryMyelofibrosis (MF) patients can present with a wide spectrum of disease characteristics. We analysed the consistency of ruxolitinib efficacy across patient subgroups in the COntrolled MyeloFibrosis Study With ORal JAK Inhibitor Treatment (COMFORT‐I,) a double‐blind trial, where patients with intermediate‐2 or high‐risk MF were randomized to twice‐daily oral ruxolitinib (n = 155) or placebo (n = 154). Subgroups analysed included MF subtype (primary, post‐polycythaemia vera, post‐essential thrombocythaemia), age (≤65, > 65 years), International Prognostic Scoring System risk group, baseline Eastern Cooperative Oncology Group performance status (0, 1, ≥2), JAK2 V617F mutation (positive, negative), baseline haemoglobin level (≥100, <100 g/l), baseline platelet count (100–200 × 109/l, >200 × 109/l), baseline palpable spleen size (≤10, >10 cm), and baseline quartile of spleen volume and Total Symptom Score (TSS; Q1 = lowest, Q4 = highest). Mean percentage change from baseline to week 24 in spleen volume and TSS were calculated for ruxolitinib and placebo in each subgroup. Overall survival was estimated by Kaplan–Meier method according to original randomization group. In ruxolitinib‐treated patients, reductions in spleen volume and TSS and evidence of improved survival relative to placebo across subgroups were consistent with those seen in the COMFORT‐I population, confirming that ruxolitinib is an effective therapy for the spectrum of MF patients studied in COMFORT‐I.

Purpose To assess the effects of ruxolitinib on symptom burden and quality of life (QoL) and to evaluate the ability of the modified Myelofibrosis Symptom Assessment Form (MFSAF) v2.0 to measure meaningful changes in myelofibrosis-related symptoms in patients with myelofibrosis. Patients and Methods COMFORT-I (Controlled Myelofibrosis Study With Oral JAK Inhibitor Treatment–I) is a double-blind, placebo-controlled phase III study evaluating ruxolitinib in patients with intermediate-2 or high-risk myelofibrosis. Exploratory analyses were conducted on the following patient-reported outcomes (PROs) assessments: modified MFSAF v2.0 (individual symptoms and Total Symptom Score [TSS]), European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), Patient Reported Outcomes Measurement Information System (PROMIS) Fatigue Scale, and Patient Global Impression of Change (PGIC). Results Patients receiving ruxolitinib experienced improvements in individual myelofibrosis-related symptoms, although patients receiving placebo experienced worsening (P < .001). The majority (91%) of ruxolitinib-treated patients designated as ≥ 50% TSS responders (≥ 50% TSS improvement) self-reported their condition as either “Much improved” or “Very much improved” on the PGIC. These patients achieved significant improvements in the EORTC QLQ-C30 functional domains and Global Health Status/QoL versus patients receiving placebo, who experienced worsening on these measures (P ≤ .0135). Ruxolitinib-treated patients with a lesser degree of symptom improvement (< 50% TSS responders) also achieved improvements over placebo on these measures. The degree of spleen volume reduction with ruxolitinib correlated with improvements in TSS, PGIC, PROMIS Fatigue Scale, and EORTC Global Health Status/QoL. Ruxolitinib-treated patients who achieved a ≥ 35% reduction in spleen volume experienced the greatest improvements in these PROs. Conclusion Ruxolitinib-treated patients achieved clinically meaningful improvements in myelofibrosis-related symptoms and QoL, but patients receiving placebo reported worsening of symptoms and other PROs.

Abstract Systemic mastocytosis (SM) is characterized by accumulation of neoplastic mast cells and is classified into indolent and aggressive forms. The latter include aggressive SM (ASM), mast cell leukemia (MCL), and SM associated with a myeloid neoplasm wherein 1 or both disease compartments exhibit advanced features. These variants, henceforth collectively referred to as advanced SM for the purposes of this report, are typically characterized by organ damage and shortened survival duration. In contrast to indolent SM, in which symptoms are usually managed by noncytotoxic antimediator therapy, cytoreduction is usually necessary for disease control in advanced SM. Unfortunately, current drug treatment of these patients rarely results in complete clinical and histopathologic remissions or improved survival time. Previously defined response criteria were adapted to the heterogeneous presentations of advanced SM and the limited effects of available drugs. However, recent advances in understanding the molecular pathogenesis of SM and the corresponding prospect in targeted therapy make it a priority to modify these criteria. Our current study is the product of an international group of experts and summarizes the challenges in accomplishing this task and forwards a new proposal for response criteria, which builds on prior proposals and should facilitate response evaluation in clinical trials.

SummaryFollowing the discovery of the Janus kinase (JAK) 2 V617F mutation in 2005 the explosion of research and drug development activity has not only advanced our understanding of the pathogenesis of myeloproliferative neoplasms (MPNs) but also triggered debate about classification, allowed revised diagnostic and response criteria, provided a target for treatment and a mode of monitoring its success. These changes and the resultant clinical research are discussed in this article where we argue that discovery of the JAK2 V617F mutation has signalled the much delayed change in therapeutic paradigm for myelofibrosis and possibly other MPNs from palliation and allowing us to move closer to, but not yet attain, a cure.