Search

Allogeneic hematopoietic cell transplantation (HCT) is the only curative therapy for myelofibrosis (MF) and is recommended for patients with higher risk disease. However, there is a risk of early mortality, and optimal timing is unknown. JAK inhibitor (JAKi) therapy may offer durable improvement in symptoms, splenomegaly and quality of life. The aim of this multicentre, retrospective observational study was to compare outcomes of patients aged 70 years or below with MF in chronic phase who received upfront JAKi therapy vs. upfront HCT in dynamic international prognostic scoring system (DIPSS)-stratified categories. For the whole study cohort, median overall survival (OS) was longer for patients who received a JAKi vs. upfront HCT, 69 (95% CI 57-89) vs. 42 (95% CI 20-not reached, NR) months, respectively (p = 0.01). In patients with intermediate-2 and high-risk disease, median OS was 55 (95% CI 36-73) months with JAKi vs. 36 (95% CI 20-NR) months for HCT (p = 0.27). An upfront HCT strategy was associated with early mortality and difference in median OS was not observed in any risk group by 5 years of follow-up. Within the limitations of a retrospective observational study, we did not observe any benefit of a universal upfront HCT approach for higher-risk MF., (© 2023. The Author(s).)

Purpose: Myelofibrosis (MF) is a clonal myeloproliferative neoplasm characterized by systemic symptoms, cytopenias, organomegaly, and bone marrow fibrosis. JAK2 inhibitors afford symptom and spleen burden reduction but do not alter the disease course and frequently lead to thrombocytopenia. TGFβ, a pleiotropic cytokine elaborated by the MF clone, negatively regulates normal hematopoiesis, downregulates antitumor immunity, and promotes bone marrow fibrosis. Our group previously showed that AVID200, a potent and selective TGFβ 1/3 trap, reduced TGFβ1-induced proliferation of human mesenchymal stromal cells, phosphorylation of SMAD2, and collagen expression. Moreover, treatment of MF mononuclear cells with AVID200 led to increased numbers of progenitor cells (PC) with wild-type JAK2 rather than JAK2V617F., Patients and Methods: We conducted an investigator-initiated, multicenter, phase Ib trial of AVID200 monotherapy in 21 patients with advanced MF., Results: No dose-limiting toxicity was identified at the three dose levels tested, and grade 3/4 anemia and thrombocytopenia occurred in 28.6% and 19.0% of treated patients, respectively. After six cycles of therapy, two patients attained a clinical benefit by IWG-MRT criteria. Spleen and symptom benefits were observed across treatment cycles. Unlike other MF-directed therapies, increases in platelet counts were noted in 81% of treated patients with three patients achieving normalization. Treatment with AVID200 resulted in potent suppression of plasma TGFβ1 levels and pSMAD2 in MF cells., Conclusions: AVID200 is a well-tolerated, rational, therapeutic agent for the treatment of patients with MF and should be evaluated further in patients with thrombocytopenic MF in combination with agents that target aberrant MF intracellular signaling pathways., (©2023 The Authors; Published by the American Association for Cancer Research.)

Purpose: Thrombocytopenia is a serious complication of myelodysplastic syndromes (MDS) associated with an increased bleeding risk and worse prognosis. Eltrombopag (ELT), a thrombopoietin receptor agonist, can increase platelet counts and reverse anti-megakaryopoietic effects of lenalidomide (LEN) in preclinical studies. We hypothesized ELT would reduce the incidence of thrombocytopenia in MDS., Patients and Methods: We conducted a Phase II multicenter trial of ELT and LEN in adult patients with low- or intermediate-1-risk MDS with symptomatic or transfusion-dependent anemia or thrombocytopenia (NCT01772420). Thrombocytopenic patients were started on ELT and subsequently treated with LEN after platelets were increased. Patients without thrombocytopenia were started on LEN monotherapy and treated with ELT if they became thrombocytopenic., Results: Fifty-two patients were enrolled; mean age was 71 years (range 34-93). Overall response rate (ORR) in the intention-to-treat population was 35% (18/52). ELT monotherapy led to ORR of 33.3% (7/21), 29% achieving hematologic improvement (HI)-Platelets, and 24% bilineage responses. LEN monotherapy had 38% ORR (6/16) with all responders achieving HI-Erythroid. Fifteen patients received both ELT and LEN with ORR of 33.3%, 20% achieved HI-Erythroid, and 20% HI-Platelets with 13% bilineage responses. Median duration of response was 40 weeks for ELT (range 8-ongoing), 41 weeks (25-ongoing) for LEN, and 88 weeks (8.3-ongoing) for ELT/LEN. Non-hematologic grade 3-4 treatment-related adverse events were infrequent. Among patients on ELT, 2 had major bleeding events, 1 had a reversible increase in peripheral blasts, and 1 developed marrow fibrosis after 6 years on ELT., Conclusions: ELT and LEN are well tolerated and effective in achieving hematologic improvement in patients with low-/intermediate-risk MDS., (©2022 American Association for Cancer Research.)

The safety profile of the novel oral JAK2/IRAK1 inhibitor pacritinib in patients with cytopenic myelofibrosis was described in the Phase 2 PAC203 and Phase 3 PERSIST-2 studies. To account for longer treatment durations on the pacritinib arms compared to best available therapy (BAT), we present a risk-adjusted safety analysis of event rates accounting for different time on treatment. While the rate of overall events was higher on pacritinib compared to BAT, the rate of fatal events was lower, and there was no excess in bleeding, cardiac events, secondary malignancy, or thrombosis on pacritinib, including in patients with severe thrombocytopenia., Competing Interests: Naveen Pemmaraju serves on the board of directors for Dan's House of Hope; consults for AbbVie, Aptitude Health, Astellas Pharma US Inc., Blueprint Medicines, Bristol‐Myers Squibb, Celgene, Cimeio Therapeutics AG, Clear View Healthcare Partners, CTI BioPharma, Dava Oncology, Immunogen, Incyte, Intellisphere LLC., Novartis, OncLive (owned by Intellisphere LLC), Patient Power, PharmaEssentia, Protagonist Therapeutics, Sanofi‐aventis, Stemline Therapeutics Inc., and Total CME; has served on scientific/advisory committees for Cancer.Net, CareDx, CTI BioPharma, EUSA Pharma Inc., Novartis, Pacylex, and PharmaEssentia; and reports speaker/preceptorship for AbbVie, Aplastic Anemia & MDS International Foundation, Curio Science LLC, Dava Oncology, Imedex, Magdalen Medical Publishing, Medscape, Neopharm, PeerView Institute for Medical Education, Physician Education Resource (PER), Physicians Education Resource (PER), Postgraduate Institute for Medicine, and Stemline Therapeutics Inc. Claire Harrison received honoraria from AbbVie, CTI BioPharma, Geron, Janssen, and Novartis; has served in consulting/advisory capacity for AOP, Celgene/ BMS, Constellation Pharmaceuticals, CTI BioPharma, Galecto, Geron, Gilead, Janssen, Keros, Promedior, Roche, Shire, Sierra Oncology, and Novartis; has served on a speakers bureau for AbbVie, BMS, CTI BioPharma, Geron, Sierra Oncology, and Novartis; and has received research funding from BMS, Constellation Pharmaceuticals, and Novartis. Vikas Gupta has consulted for AbbVie, Celgene/BMS, Constellation Pharmaceuticals, Novartis, Pfizer, and Sierra Oncology; he has received honoraria from Celgene/BMS, Constellation Pharmaceuticals, and Novartis; and has served in consulting/advisory capacity for AbbVie, Celgene/BMS, Pfizer, and Roche. Srdan Verstovsek has consulted for BMS, Constellation Pharmaceuticals, Incyte, Novartis, and Sierra Oncology; and has received researching funding from AstraZeneca, Blueprint Medicines, Celgene, CTI BioPharma, Genentech, Gilead, Incyte, Italfarmaco, Novartis, NS Pharma Inc., PharmaEssentia, Promedior, Protagonist Therapeutic, Roche, and Sierra Oncology. Bart Scott has consulted for Acceleron Pharma, Celgene, and Novartis; has served on speakers’ bureaus for Alexion Pharmaceuticals, Celgene, Jazz Pharmaceuticals, and Novartis; has received honoraria from BMS, Incyte, and Taiho Oncology, and reports his institution receiving research funding from Celgene. Stephen T. Oh has consulted for AbbVie, Blueprint Medicines, Celgene/BMS, Constellation Pharmaceuticals, CTI BioPharma, Disc Medicine, Geron, Incyte, and PharmaEssentia; and has received research funding from Actuate Therapeutics, Blueprint Medicines, Celgene/BMS, Constellation Pharmaceuticals, CTI BioPharma, Incyte, Kartos Therapeutics, Sierra Oncology, and Takeda. Francesca Palandri received honoraria and has served in consulting/advisory capacity for AOP, Celgene, CTI BioPharma, Novartis, and Sierra Oncology. Haifa Kathrin Al‐Ali has received grants from BMS, Deutsche Leukämie und Lymphom Stiftung, and East German Study Group for Hematology and Oncology; and has consulted for AbbVie, AOP, Blueprint Medicines, BMS, Novartis, Pfizer, and Takeda. Marta Sobas received honoraria and has served in consulting/advisory capacity for Celgene, CTI BioPharma, and Novartis. Mary Frances McMullin has served in consulting/advisory capacity for AbbVie, BMS, Incyte, Novartis, and Sierra Oncology; and has served on a speakers’ bureau for AbbVie, AOP, Incyte, Pfizer, and Novartis. Ruben Mesa has consulted for Constellation Pharmaceuticals, LaJolla Pharmacuetical, Novartis, and Sierra Oncology; has received research support from AbbVie, Celgene, Constellation Pharmaceuticals, CTI BioPharma, Genotech, Incyte, Promedior, and Samus; and has received a P30 grant (Mays Cancer Center P30 Cancer Center Support Grant) from National Cancer Institute (CA054174). Sarah Buckley is employed by, owns stock in, and has received travel funding from CTI BioPharma. Karisse Roman‐Torres is employed by and owns stock in CTI BioPharma. Alessandro Vannucchi has served in consulting/advisory capacity and has served on speakers’ bureaus for AbbVie, AOP, Blueprint Medicines, BMS, Incyte, and Novartis. Abdulraheem Yacoub has served in consulting/advisory capacity for AbbVie, Acceleron Pharma, Apellis, CTI BioPharma, Gilead, Incyte, Notable Labs., Novartis, Pfizer, PharmaEssentia, and Servier., (© 2022 The Authors. eJHaem published by British Society for Haematology and John Wiley & Sons Ltd.)

Introduction: Decreasing efficacy over time and initial suboptimal response to Janus kinase (JAK) inhibitors such as ruxolitinib in a subset of patients are critical clinical challenges associated with myeloproliferative neoplasms (MPNs), primarily myelofibrosis., Areas Covered: The role of phosphatidylinositol-3 kinase (PI3K) in MPN disease progression and treatment resistance and as a potential therapeutic target in patients who experience loss of response to JAK inhibition is discussed. Understanding the complex signaling networks involved in the pathogenesis of MPNs has identified potentially novel therapeutic targets and treatment strategies, such as inhibiting other signaling pathways in addition to the JAK/signal transducer and activator of transcription (STAT) pathway. PI3K plays a crucial role downstream of JAK signaling in rescuing tumor cell proliferation, with PI3Kδ being particularly important in hematologic malignancies. Concurrent targeting of both PI3K and JAK/STAT pathways may offer an innovative therapeutic strategy to maximize efficacy., Expert Opinion: Based on our understanding of the underlying mechanisms and the role of PI3K pathway signaling in the loss of response or resistance to JAK inhibitor treatment and initial results from clinical studies, the combination of parsaclisib (PI3Kδ inhibitor) and ruxolitinib holds great clinical potential. If confirmed in larger clinical trials, parsaclisib may provide more treatment options and improve clinical outcomes for patients with MPNs.

Idasanutlin, an MDM2 antagonist, showed clinical activity and a rapid reduction in JAK2 V617F allele burden in patients with polycythemia vera (PV) in a phase 1 study. This open-label phase 2 study evaluated idasanutlin in patients with hydroxyurea (HU)-resistant/-intolerant PV, per the European LeukemiaNet criteria, and phlebotomy dependence; prior ruxolitinib exposure was permitted. Idasanutlin was administered once daily on days 1 through 5 of each 28-day cycle. The primary end point was composite response (hematocrit control and spleen volume reduction > 35%) in patients with splenomegaly and hematocrit control in patients without splenomegaly at week 32. Key secondary end points included safety, complete hematologic response (CHR), patient-reported outcomes, and molecular responses. All patients (n = 27) received idasanutlin; 16 had response assessment (week 32). Among responders with baseline splenomegaly (n = 13), 9 (69%) attained any spleen volume reduction, and 1 achieved composite response. Nine patients (56%) achieved hematocrit control, and 8 patients (50%) achieved CHR. Overall, 43% of evaluable patients (6/14) showed a ≥50% reduction in the Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (week 32). Nausea (93%), diarrhea (78%), and vomiting (41%) were the most common adverse events, with grade ≥ 3 nausea or vomiting experienced by 3 patients (11%) and 1 patient (4%), respectively. Reduced JAK2 V617F allele burden occurred early (after 3 cycles), with a median reduction of 76%, and was associated with achieving CHR and hematocrit control. Overall, the idasanutlin dosing regimen showed clinical activity and rapidly reduced JAK2 allele burden in patients with HU-resistant/- intolerant PV but was associated with low-grade gastrointestinal toxicity, leading to poor long-term tolerability. This trial was registered at www.clinincaltrials.gov as #NCT03287245., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Background: Patients with essential thrombocythaemia or polycythaemia vera have several symptoms that can worsen their quality of life. We aimed to assess how symptom burden changes over time with cytoreductive therapy., Methods: We performed a post-hoc analysis of data from MPN-RC 111-a single-arm, open-label, phase 2, multicentre trial at 17 hospitals and cancer centres in Italy and the USA, evaluating the clinical-haematological response to pegylated interferon alfa-2a in patients who were resistant or intolerant to hydroxyurea (NCT01259817)-and MPN-RC 112-a randomised, open-label, phase 3, multicentre trial at 25 hospitals and cancer centres in France, Germany, Israel, Italy, the UK, and the USA, comparing the clinical-haematological response to pegylated interferon alfa-2a versus hydroxyurea in therapy-naive patients with either high-risk essential thrombocythaemia or polycythaemia vera (NCT01258856). Patients completed the Myeloproliferative Neoplasm Symptom Assessment Form (MPN-SAF) and the European Organisation for the Research and Treatment of Cancer Core Quality of Life Questionnaire through 12 months after initiation of treatment as secondary endpoints. In this post-hoc analysis, we examined the association of symptom burden with the clinical-haematological response at 12 months and the effect of baseline symptom burden (ie, high burden [total symptom score ≥20] vs low burden [total symptom score <20]) on subsequent changes in symptoms, estimated via mixed models. A clinically significant improvement in symptom burden was defined as 50% or greater improvement in the MPN-SAF total symptom score from baseline to 12 months in patients with a total symptom score greater than zero at baseline., Findings: 135 patients were enrolled in MPN-RC 111 between Feb 15, 2012, and Dec 23, 2015, and 168 were enrolled in MPN-RC 112 between Sept 24, 2011, and June 30, 2016. For this analysis, we included data from 114 patients from MPN-RC 111 (64 [56%] with essential thrombocythaemia and 50 [44%] with polycythaemia vera; 56 [49%] were female, and 100 [91%] of 110 were white) and 166 patients from MPN-RC 112 (79 [48%] with essential thrombocythaemia and 87 [52%] with polycythaemia vera; 68 [41%] were female, and 145 [93%] of 156 were white). At 12 months, a clinically significant improvement in symptom burden was reported by 12 (32%) of 38 complete responders and seven (20%) of 35 partial responders treated with pegylated interferon alfa-2a in MPN-RC 111; five (19%) of 27 complete responders and six (18%) of 34 partial responders treated with pegylated interferon alfa-2a in MPN-112; and eight (27%) of 30 complete responders and six (22%) of 27 partial responders treated with hydroxyurea in MPN-112. More complete and partial responders reported a clinically significant improvement than did non-responders (44 [22%] of 191 complete and partial responders vs four [5%] of 76 non-responders; Fisher's exact p=0·0003). Symptom burden improved between 3 and 12 months in patients with high baseline symptom burden, both those treated with pegylated interferon alfa-2a (mean total symptom score change -10·2, 95% CI -13·2 to -7·2) and those treated with hydroxyurea (-6·8, -11·2 to -2·4). However, symptom burden worsened between 3 and 12 months in patients with low baseline symptom burden (patients treated with pegylated interferon alfa-2a: mean total symptom score change 3·2, 95% CI 0·9 to 5·4; patients treated with hydroxyurea: 3·4, 0·6 to 6·2)., Interpretation: Results can inform treatment decisions, including treatment timing and goals in managing essential thrombocythaemia and polycythaemia vera, because measuring symptom burden from the patient perspective is crucial to understanding treatment efficacy and tolerability., Funding: US National Cancer Institute of the National Institutes of Health, and Roche Genentech., Competing Interests: Declaration of interests JM reports funding from PharmaEssentia and consulting fees from PharmaEssentia. RAM reports funding from Celgene, Incyte, AbbVie, Samus, Genotech, Promedior, CTI, and Constellation; and consulting fees from Novartis, Sierra Onc, LaJolla, Pharma, and Constellation. All other authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This review reflects the presentations and discussion at the 14th post-American Society of Hematology (ASH) International Workshop on Chronic Myeloproliferative Malignancies, which took place on the December 10 and 11, 2019, immediately after the 61st ASH Annual Meeting in Orlando, Florida. Rather than present a resume of the proceedings, we address some of the topical translational science research and clinically relevant topics in detail. We consider how recent studies using single-cell genomics and other molecular methods reveal novel aspects of hematopoiesis which in turn raise the possibility of new therapeutic approaches for patients with myeloproliferative neoplasms (MPNs). We discuss how alternative therapies could benefit patients with chronic myeloid leukemia who develop BCR-ABL1 mutant subclones following ABL1-tyrosine kinase inhibitor therapy. In MPNs, we focus on efforts beyond JAK-STAT and the merits of integrating activin receptor ligand traps, interferon-α, and allografting in the current treatment algorithm for patients with myelofibrosis., (© 2020 The Authors. Hematological Oncology published by John Wiley & Sons Ltd.)

PAC203 is a randomized dose-finding study of pacritinib, an oral JAK2/IRAK1 inhibitor, in patients with advanced myelofibrosis who are intolerant of or resistant to ruxolitinib. Patients were randomized 1:1:1 to pacritinib 100 mg once per day, 100 mg twice per day, or 200 mg twice per day. Enhanced eligibility criteria, monitoring, and dose modifications were implemented to mitigate risk of cardiac and hemorrhagic events. Efficacy was based on ≥35% spleen volume response (SVR) and ≥50% reduction in the 7-component total symptom score (TSS) through week 24. Of 161 patients, 73% were intolerant of and 76% had become resistant to ruxolitinib; 50% met criteria for both. Severe thrombocytopenia (platelet count <50 × 103/μL) was present in 44%. SVR rates were highest with 200 mg twice per day (100 mg once per day, 0%; 100 mg twice per day, 1.8%; 200 mg twice per day, 9.3%), particularly among patients with baseline platelet counts <50 × 103/μL (17%; 4 of 24). Although TSS response rate was similar across doses (100 mg once per day, 7.7%; 100 mg twice per day, 7.3%; 200 mg twice per day, 7.4%), median percent reduction in TSS suggested a dose-response relationship (-3%, -16%, and -27%, respectively). Pharmacokinetic and pharmacodynamic modeling based on all available data showed greatest SVR and TSS reduction at 200 mg twice per day compared with lower doses. Common adverse events were gastrointestinal events, thrombocytopenia, and anemia. There was no excess of grade ≥3 hemorrhagic or cardiac events at 200 mg twice per day. Pacritinib 200 mg twice per day demonstrated clinical activity and an acceptable safety profile and was selected as the recommended dose for a pivotal phase 3 study in patients with myelofibrosis and severe thrombocytopenia. This trial was registered at www.clinicaltrials.gov as #NCT03165734., (© 2020 by The American Society of Hematology.)

Prior studies have reported high response rates with recombinant interferon-α (rIFN-α) therapy in patients with essential thrombocythemia (ET) and polycythemia vera (PV). To further define the role of rIFN-α, we investigated the outcomes of pegylated-rIFN-α2a (PEG) therapy in ET and PV patients previously treated with hydroxyurea (HU). The Myeloproliferative Disorders Research Consortium (MPD-RC)-111 study was an investigator-initiated, international, multicenter, phase 2 trial evaluating the ability of PEG therapy to induce complete (CR) and partial (PR) hematologic responses in patients with high-risk ET or PV who were either refractory or intolerant to HU. The study included 65 patients with ET and 50 patients with PV. The overall response rates (ORRs; CR/PR) at 12 months were 69.2% (43.1% and 26.2%) in ET patients and 60% (22% and 38%) in PV patients. CR rates were higher in CALR-mutated ET patients (56.5% vs 28.0%; P = .01), compared with those in subjects lacking a CALR mutation. The median absolute reduction in JAK2V617F variant allele fraction was -6% (range, -84% to 47%) in patients achieving a CR vs +4% (range, -18% to 56%) in patients with PR or nonresponse (NR). Therapy was associated with a significant rate of adverse events (AEs); most were manageable, and PEG discontinuation related to AEs occurred in only 13.9% of subjects. We conclude that PEG is an effective therapy for patients with ET or PV who were previously refractory and/or intolerant of HU. This trial was registered at www.clinicaltrials.gov as #NCT01259856., (© 2019 by The American Society of Hematology.)

This phase 1/2 study assessed parsaclisib (INCB050465), a next-generation, potent, and highly selective phosphatidylinositol 3-kinase δ (PI3Kδ) inhibitor, in patients with relapsed or refractory B-cell malignancies, alone or in combination with a Janus kinase 1 inhibitor (itacitinib) or chemotherapy (rituximab, ifosfamide, carboplatin, and etoposide). Seventy-two patients received parsaclisib monotherapy (5-45 mg once daily). Expansion doses were 20 and 30 mg once daily; intermittent dosing at 20 mg (once daily for 9 weeks, then once weekly) was explored. No dose-limiting toxicities were identified, and maximum tolerated dose was not reached. Most common nonhematologic treatment-emergent adverse events (TEAEs) were diarrhea/colitis (36%), nausea (36%), fatigue (31%), and rash (31%). Grade 3/4 neutropenia occurred in 19% of patients. Serious TEAEs (>2 patients) were diarrhea/colitis (n = 9), pyrexia (n = 4), hypotension (n = 3), and sepsis (n = 3). Aspartate and alanine transaminase elevations occurring before treatment discontinuation were grade 1, except 1 grade 3 event each, secondary to sepsis. Two patients experienced 3 fatal parsaclisib-unrelated TEAEs (respiratory failure; respiratory failure and sepsis). In non-Hodgkin lymphoma (NHL), objective response rates to monotherapy were 71% in follicular lymphoma, 78% in marginal zone lymphoma, 67% in mantle cell lymphoma, and 30% in diffuse large B-cell lymphoma; 93% of responses occurred at first assessment (∼9 weeks). Parsaclisib has demonstrated antitumor activity in relapsed or refractory B-cell NHL with the potential for improved long-term patient outcomes. Phase 2 studies in relapsed or refractory B-cell NHL subtypes are ongoing. This trial was registered at www.clinicaltrials.gov as #NCT02018861., (© 2019 by The American Society of Hematology.)