ABSTRACT:Nonmelanoma skin cancers (NMSCs) in ruxolitinib-treated patients with myeloproliferative neoplasms behave aggressively, with adverse features and high recurrence. In our cohort, mortality from metastatic NMSC exceeded that from myelofibrosis. Vigilant skin assessment, counseling on NMSC risks, and prospective ruxolitinib-NMSC studies are crucial.

Current therapies for myeloproliferative neoplasms (MPNs) improve symptoms but have limited effect on tumor size. In preclinical studies, tamoxifen restored normal apoptosis in mutated hematopoietic stem/progenitor cells (HSPCs). TAMARIN Phase-II, multicenter, single-arm clinical trial assessed tamoxifen’s safety and activity in patients with stable MPNs, no prior thrombotic events and mutated JAK2 V617F , CALR ins5 or CALR del52 peripheral blood allele burden ≥20% (EudraCT 2015-005497-38). 38 patients were recruited over 112w and 32 completed 24w-treatment. The study’s A’herns success criteria were met as the primary outcome ( ≥ 50% reduction in mutant allele burden at 24w) was observed in 3/38 patients. Secondary outcomes included ≥25% reduction at 24w (5/38), ≥50% reduction at 12w (0/38), thrombotic events (2/38), toxicities, hematological response, proportion of patients in each IWG-MRT response category and ELN response criteria. As exploratory outcomes, baseline analysis of HSPC transcriptome segregates responders and non-responders, suggesting a predictive signature. In responder HSPCs, longitudinal analysis shows high baseline expression of JAK-STAT signaling and oxidative phosphorylation genes, which are downregulated by tamoxifen. We further demonstrate in preclinical studies that in JAK2V617F+ cells, 4-hydroxytamoxifen inhibits mitochondrial complex-I, activates integrated stress response and decreases pathogenic JAK2-signaling. These results warrant further investigation of tamoxifen in MPN, with careful consideration of thrombotic risk.

PURPOSE:Polycythemia vera (PV) is characterized by JAK/STAT activation, thrombotic/hemorrhagic events, systemic symptoms, and disease transformation. In high-risk PV, ruxolitinib controls blood counts and improves symptoms. PATIENTS AND METHODS:MAJIC-PV is a randomized phase II trial of ruxolitinib versus best available therapy (BAT) in patients resistant/intolerant to hydroxycarbamide (HC-INT/RES). Primary outcome was complete response (CR) within 1 year. Secondary outcomes included duration of response, event-free survival (EFS), symptom, and molecular response. RESULTS:One hundred eighty patients were randomly assigned. CR was achieved in 40 (43%) patients on ruxolitinib versus 23 (26%) on BAT (odds ratio, 2.12; 90% CI, 1.25 to 3.60; P = .02). Duration of CR was superior for ruxolitinib (hazard ratio [HR], 0.38; 95% CI, 0.24 to 0.61; P < .001). Symptom responses were better with ruxolitinib and durable. EFS (major thrombosis, hemorrhage, transformation, and death) was superior for patients attaining CR within 1 year (HR, 0.41; 95% CI, 0.21 to 0.78; P = .01); and those on ruxolitinib (HR, 0.58; 95% CI, 0.35 to 0.94; P = .03). Serial analysis of JAK2V617F variant allele fraction revealed molecular response was more frequent with ruxolitinib and was associated with improved outcomes (progression-free survival [PFS] P = .001, EFS P = .001, overall survival P = .01) and clearance of JAK2V617F stem/progenitor cells. ASXL1 mutations predicted for adverse EFS (HR, 3.02; 95% CI, 1.47 to 6.17; P = .003). The safety profile of ruxolitinib was as previously reported. CONCLUSION:The MAJIC-PV study demonstrates ruxolitinib treatment benefits HC-INT/RES PV patients with superior CR, and EFS as well as molecular response; importantly also demonstrating for the first time, to our knowledge, that molecular response is linked to EFS, PFS, and OS.

This document represents an update of the British Society for Haematology (BSH) guideline on myelofibrosis (MF) first published in 2012 and updated in 2015.1 This guideline aims to provide healthcare professionals with clear guidance on the diagnosis and prognostic evaluation of primary myelofibrosis (PMF), as well as post-polycythaemia vera myelofibrosis (post-PV MF) and post-essential thrombocythaemia myelofibrosis (post-ET MF). A section on prefibrotic MF is also included. A separate BSH Guideline covers the management of MF and is published alongside this guideline. These guidelines were compiled according to the BSH process https://b-s-h.org.uk/media/16732/bsh-guidance-development-process-dec-5-18.pdf. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluate levels of evidence and to assess the strength of recommendations. The GRADE criteria can be found at http://www.gradeworkinggroup.org. Recommendations are based on a review of the relevant MF-related literature using Medline, PubMed/Medline and Cochrane searches beginning from 2012 up to mid-2022. Filters were applied to include only publications written in English, studies carried out in humans, clinical conferences, congresses, clinical trials, clinical studies, meta-analyses, multicentre studies and randomised controlled trials. Exclusion criteria included papers published in non-English journals and those publications without an abstract. Review of the manuscript was performed by the BSH Guidelines Committee Haemato-oncology Task Force, the BSH Guidelines Committee and the Haemato-oncology sounding board of the BSH. We invited two global expert external reviewers to review contents—Professor Ruben Mesa and Professor Alessandro Vannucchi. This guideline has also been reviewed by patient representatives from MPN Voice. Myelofibrosis encompasses PMF, post-ET MF and post-PV MF. It is characterised by clonal haematopoietic stem cell proliferation and elevated levels of pro-inflammatory cytokines, resulting in reticulin deposition and collagen fibrosis. The annual incidence is estimated at 1–2 individuals per 100 000 of the population in the United Kingdom, with an equal sex incidence.2 All patients newly diagnosed with MF should be reported to the National Cancer Registry, via the multidisciplinary meeting, and to MF-specific registries if available. Clinical features of MF are heterogeneous and may include anaemia, leucocytosis and extramedullary haemopoiesis, with progressive splenomegaly. Patients may experience constitutional symptoms, consequences of progressive splenomegaly (pain, early satiety, portal hypertension and dyspnoea), progressive marrow failure and have an inherent risk of leukaemic transformation. Palpable splenomegaly is present in up to 80% of patients. Clinical palpation is the easiest method to evaluate spleen size, with the patient in the supine position. Ideally, a simple measuring tape can be used to record the size of an enlarged spleen below the left costal margin in centimetres (cm). Ultrasound may aid spleen size determination in a more uniform manner. In MF trials, the International Working Group-Myeloproliferative Neoplasm Research and Treatment (IWG-MRT) criteria utilised spleen volume as part of the clinical improvement response; this can be derived from computed tomography or magnetic resonance imaging. This is not a requirement in routine clinical practice. Myelofibrosis frequently has a significant symptom burden that can negatively impact on quality of life, activities of daily living and functional status. Validated tools that have been developed to objectively measure symptom burden include the MF Symptom Assessment Form (MF SAF), MPN Symptom Assessment Form (MPN SAF) and MPN-SAF Total Symptom Score (MPN-SAF TSS—MPN 10).3, 4 The MPN-SAF TSS is an abbreviated symptom assessment tool that measures 10 symptoms through patient self-assessment on a linear scale from 0 (absent) to 10 (worst imaginable), namely: fatigue, early satiety, abdominal discomfort, inactivity, concentration problems, night sweats, pruritus, bone pain, fever and weight loss. Regular use of MPN-SAF TSS provides an indication of symptom status and treatment response and should be performed at each clinical review as appropriate. Thrombosis risk is often underestimated in MF, in particular for those in the so-called lower prognostic groups with a JAK2 V617F mutation.5 An individualised risk assessment is warranted. Finally, it is well established that some MF patients are at risk of non-cirrhotic portal hypertension, in particular those with bulky splenomegaly.6 Where clinical signs (e.g. the presence of ascites, anterior abdominal wall dilated veins or signs associated with liver impairment) or liver imaging/transient elastography suggest the presence of portal hypertension, consideration should be given, in appropriate cases, for an oesophagogastroduodenoscopy (OGD) to be performed to rule out occult varices. Patients classically present with progressive anaemia, a leucoerythroblastic blood film with teardrop poikilocytes, splenomegaly and constitutional symptoms. These, along with pathogenic mutations (see below) and typical bone marrow (BM) morphological findings, form the basis of the diagnostic criteria proposed by both the World Health Organization (WHO) and the International Consensus Classification (ICC; Table 1).7, 8 Any patient being investigated for potential MPN with suspicious clinical features or atypical peripheral blood (PB) findings (cytopenia, left-shifted granulopoiesis, circulating blasts) should proceed to BM examination, which is essential for the diagnosis.9 A key morphological finding in the BM is a proliferation of atypical megakaryocytes,7 showing clustering and abnormal localisation with hyperchromatic or bulbous nuclei, lying within an increased reticulin network with focal or diffuse collagen.10 In advanced stages, osteosclerosis can be extensive. To establish a diagnosis and define the disease, reticulin grading is essential with a minimum of grade 2 (0–3 grading system).11 Commercial reticulin staining kits detect only reticulin fibrosis necessitating additional staining for collagen (trichrome stain).10-12 Separate scoring systems for collagen fibrosis and osteosclerosis have been recommended.7, 12 These may enable more accurate response assessment in patients receiving disease modifying therapies, although their clinical impact is yet to be established.12, 13 The BM should be reported in a Specialist Integrated Haematological Malignancy Diagnostic Service (SIHMDS) and as per either the WHO or ICC criteria. The classification used should be stated in the report and consideration should be given to stating the diagnosis according to both classifications. It is essential to distinguish MF from other myeloid malignancies, and careful morphological assessment for features such as the degree of dysplasia is required.14 In particular, it is important to highlight that systemic mastocytosis can be associated with significant marrow fibrosis. In patients with monocytosis, distinguishing between MF and chronic myelomonocytic leukaemia (CMML) can be challenging though genomic testing with targeted myeloid sequencing panels may help. This will not only detect mutations which are more specific to either disease but will also provide a JAK2 mutant allele burden which is frequently reported to be higher in PMF than in CMML.15, 16 Genetic tests for assessment of patients with MPN have been previously described.17 Suspected PMF cases should be screened for common MPN driver mutations (affecting the JAK2, CALR and MPL genes), on either PB- or BM-derived DNA. Between 50% and 60% of PMF cases are positive for JAK2 V617F, with the remaining 15%–35% and 6%–9% of cases testing positive for CALR exon 9 or MPL exon 10 mutations respectively.17 Type 1/Type 1-like CALR mutations are much more prevalent in PMF than Type 2/Type 2-like mutations.18 Patients with BM histology and clinical features consistent with PMF or pre-PMF who test negative for JAK2, CALR or MPL mutations should be tested further using a myeloid gene panel and, ideally, karyotyping or genome-wide single nucleotide polymorphism (SNP) array.17 Patients without a typical driver mutation in JAK2, MPL or CALR may be diagnosed as triple negative (TN) PMF, although this should prompt careful evaluation of the clinical picture and morphology to exclude the diagnosis of another myeloid neoplasm as highlighted above. In the absence of a clonal marker of disease, causes of secondary fibrosis also require exclusion (Table 2).7, 8, 19 In addition, exclusion of BCR::ABL1 is important for all TN patients with thrombocytosis and/or atypical features. For patients with a confirmed diagnosis of PMF or post-PV/ET-MF, a myeloid panel and karyotyping/SNP array, performed on either PB or BM, provide important prognostic and potentially additional therapeutic target information and are generally recommended for allogeneic haematopoietic stem cell transplantation (allo-HSCT) candidates. In other patients, including those with pre-PMF, testing may be considered for prognostic purposes and/or whether additional genomic data will guide clinical management. As a minimum, myeloid gene panels should include ASXL1, CBL, CSF3R, DNMT3A, EZH2, KIT, KRAS, IDH1/2, NRAS, RUNX1, SETBP1, SF3B1, SH2B3, SRSF2, TET2, TP53 and U2AF1, together with full coding sequence coverage of JAK2, MPL and CALR exon 9. Broader mutation screens provide additional personalised prognostic information.20-22 All cases should be discussed in a specialist multidisciplinary meeting. This should be a quorate meeting (e.g. clinical haematologists and representatives of the SIHMDS, etc.) as per national/local guidance on haemato-oncology multidisciplinary meetings. Overall survival in MF varies widely and clinicians should be aware of the strengths and limitations of the many prognostic scores available to inform clinical use and guide discussions on therapy and management. These are summarised in Table 3, with suggestions where each score may be best utilised. Age >65 years (1) Hb <100 g/L (2) WBC >25 × 109/L (1) Circulating blasts ≥1% (1) Age >65 years (1) Hb <100 g/L (2) WBC >25 × 109/L (1) Circulating blasts ≥1% (1) Constitutional symptoms (1) Age >65 years (1) Hb <100 g/L (2) WBC >25 × 109/L (1) Circulating blasts ≥1% (1) Constitutional symptoms (1) Unfavourable karyotype (1) Red cell transfusion need (1) Platelets <100 × 109/L (1) VHR karyotype (4) Unfavourable karyotype (3) ≥2 HMR mutations (3) 1 HMR mutation (2) Type 1/like CALR absent (2) Hb <80 g/L females, Hb <90 g/L Male (2) Hb 80–99 g/L Females, Hb 90–109 g/L Male (1) Circulating blasts ≥2% (1) Constitutional symptoms (2) Hb <110 g/L (2) Platelets <150 × 109/L (1) Circulating blasts ≥3% (2) CALR mutation absent (2) Constitutional symptoms (1) Age (0.15 per year of age) Age >57 years (1) WBC >25 × 109/L (1) Platelets <150 × 109/L (1) ASXL1 mutated (1) Karnofsky Performance Status <90% (1) HLA-mismatched unrelated donor (2) Not CALR/MPL mutated 2035 MPN 309 MF Validation cohort (515 MPN, 190 MF) 209 MF 40 MF in validation cohort Response to RUX after 6 months (RR6), dissected three risk categories regarding OS The International Prognostic Scoring System (IPSS) was the first risk stratification model to consider a large PMF cohort.23 IPSS identified five factors associated with reduced patient survival: age >65 years, presence of constitutional symptoms (>10% weight loss in 6 months, night sweats, unexplained fever higher than 37.5°C), haemoglobin <100 g/L, white cell count >25 × 109/L and ≥1% circulating blast cells. Use of the same five factors led to generation of the Dynamic IPSS (DIPSS) score, facilitating dynamic assessment during the disease course. This was further refined in the DIPSS-plus risk stratification by three additional risk factors (unfavourable karyotype, thrombocytopenia (platelets <100 × 109/L) and red cell transfusion dependence).24, 25 Approximately 40% of patients with PMF have an abnormal karyotype.25, 29-31 Patients with inv(3), −5/5q, −7/7q−, +8, 11q23 and 12p−, i(17q), or complex karyotypes (>2 abnormalities) have significantly poorer outcomes.29, 31-33 JAK2 V617F and MPL mutations have been associated with a worse prognosis compared to CALR mutations in several studies. Prognostic advantage of a CALR mutation may, however, only be confined to Type 1 or Type 1-like mutations.18, 34-36 Overall survival for patients with TN MF appears worse than for those patients with a JAK2- or MPL-mutation.34, 36 So-called 'high molecular risk' (HMR) pathogenic mutations in five genes (ASXL1, SRSF2, EZH2, IDH1 and IDH2) have been shown to adversely impact life expectancy and increase the likelihood of leukaemic transformation in MF.37 Patients with >1 HMR mutation have a particularly poor prognosis. Mutations in TP53, U2AF1, RUNX1, CBL, NRAS and KRAS can also confer adverse outcomes.20, 22 The mutation-enhanced IPSS (MIPSS70+ v2.0) score combines typical haematological features together with karyotype and mutations in 'HMR' genes and U2AF1 Q157.21 MIPSS70+ v2.0 (http://www.mipss70score.it/) takes into account varying severity of anaemia. The model included mainly patients <70 years with PMF and pre-PMF, and is more accurate than IPSS. Both DIPSS and MIPSS70+ v2.0 appear relevant to those patients eligible for transplant as the risk score correlates with post-transplant outcomes.38, 39 The so-called 'RR6 model' predicts survival in MF based on clinical response after 6 months of ruxolitinib (considers spleen length reduction, dose density of ruxolitinib and transfusion requirements; http://www.rr6.eu/).28 For transplant-eligible patients, the clinical-molecular myelofibrosis transplant scoring system (MTSS) combines age, haematological and molecular parameters, patient fitness and degree of HLA matching to predict survival after allo-HSCT.27 The MYSEC-PM score was developed specifically for patients with post-PV MF and post-ET MF.26 A personalised prognosis calculator for MPN patients (Predict blood; https://blood.predict.nhs.uk/) takes into account 63 patient demographic, clinical and molecular variables to predict personally tailored risk for both disease transformation and survival. The model incorporates many more variables than the risk scoring systems described above, does not dichotomise continuous risk variables (such as increasing age or worsening blood counts), and can predict several different disease outcomes simultaneously. It was shown to provide improved accuracy and greater discrimination over both DIPSS and IPSS, even when incomplete information on molecular variables was available.22 Prognostication can aid treatment decisions including allo-HSCT. No model can currently predict which patients may benefit from any particular therapy. In general, it is advisable to repeat dynamic prognostication for patients at regular intervals, for example annually, or particularly if there is clinical concern or change in disease phenotype. The diagnosis of pre-PMF and its distinction from other MPNs is also based on a combination of clinical, morphological and genomic features (Table 4).7, 8 It is important to note that pre-PMF is entirely distinct from low-risk overt MF. Distinction of ET from pre-PMF often causes the most diagnostic difficulty. Compared to ET, patients with pre-PMF tend to have higher white cell and platelet counts, lower haemoglobin levels, higher lactate dehydrogenase and greater splenomegaly, and less favourable outcomes: reduced survival, increased leukaemic transformation and increased progression to overt MF.40, 41 Pre-PMF tends to have milder clinical features and better survival than overt PMF.42, 43 There is recognised interobserver variability in distinguishing histological features of pre-PMF and ET,44-48 albeit not fully consistent across studies.49, 50 This variability, together with the proportion of patients diagnosed as unclassifiable MPN46, 51 has led to the utility of the WHO criteria being questioned. Although the IPSET thrombosis score from ET has been validated for thrombotic risk in pre-PMF,52 other conventional MF prognostic scores are not fully applicable. Novel prognostic modelling methods have been proposed for pre-PMF including mutational profiles.53 A myeloid gene panel and cytogenetic evaluation is recommended at diagnosis in patients with pre-PMF who are considered to be future allo-HSCT candidates, or where more accurate prognostic information would aid management. Most patients are currently treated pragmatically according to clinical phenotype. There is a risk of thrombosis associated with pre-PMF which must be considered. All authors contributed to guideline writing, review and editing. The writing committee would like to thank Professor Ruben Mesa and Professor Alessandro Vannucchi for their external expert review of this guideline. The authors thank the members of MPN Voice who expertly appraised these guidelines and the BSH Haemato-oncology Task Force, the BSH sounding board and the BSH Guidelines Committee for their guidance and expertise. All authors have made a declaration of interests to the BSH and Task Force Chairs which may be viewed on request. While the advice and information in this guidance is believed to be true and accurate at the time of going to press, neither the authors, the BSH nor the publishers accept any legal responsibility for the content of this guidance.

Abstract Current therapies for myeloproliferative neoplasms (MPN) improve symptoms but have limited effect on tumor size. In preclinical studies, tamoxifen restored normal apoptosis in mutated hematopoietic stem and progenitor cells (HSPCs). TAMARIN is a Phase-II, multicenter, single-arm clinical trial assessing tamoxifen’s safety and activity in patients with stable MPNs, no prior thrombotic events and mutated JAK2V617F, CALRins5 or CALRdel52 peripheral blood allele burden ≥20%. The primary outcome (≥50% allele burden reduction at 24 weeks) was met by 3/38 patients; 5/38 additional patients showed ≥25% reductions. Tamoxifen was well tolerated. Baseline analysis of HSPC transcriptome segregated responders and non-responders, suggesting a predictive signature. In responder HSPCs, longitudinal analysis showed high baseline expression of JAK-STAT signaling and oxidative phosphorylation genes, which were downregulated by tamoxifen. In JAK2V617F+ cells, 4-hydroxytamoxifen inhibited mitochondrial complex-I, activating proapoptotic integrated stress response (ISR) and decreasing pathogenic JAK2 signaling. Therefore, tamoxifen inhibits mitochondrial respiration, modulates ISR and suppresses pathogenic JAK-STAT signaling in a subset of prospectively identifiable MPN patients.

The goal of therapy for patients with essential thrombocythemia (ET) and polycythemia vera (PV) is to reduce thrombotic events by normalizing blood counts. Hydroxyurea (HU) and interferon-α (IFN-α) are the most frequently used cytoreductive options for patients with ET and PV at high risk for vascular complications. Myeloproliferative Disorders Research Consortium 112 was an investigator-initiated, phase 3 trial comparing HU to pegylated IFN-α (PEG) in treatment-naïve, high-risk patients with ET/PV. The primary endpoint was complete response (CR) rate at 12 months. A total of 168 patients were treated for a median of 81.0 weeks. CR for HU was 37% and 35% for PEG (P = .80) at 12 months. At 24 to 36 months, CR was 20% to 17% for HU and 29% to 33% for PEG. PEG led to a greater reduction in JAK2V617F at 24 months, but histopathologic responses were more frequent with HU. Thrombotic events and disease progression were infrequent in both arms, whereas grade 3/4 adverse events were more frequent with PEG (46% vs 28%). At 12 months of treatment, there was no significant difference in CR rates between HU and PEG. This study indicates that PEG and HU are both effective treatments for PV and ET. With longer treatment, PEG was more effective in normalizing blood counts and reducing driver mutation burden, whereas HU produced more histopathologic responses. Despite these differences, both agents did not differ in limiting thrombotic events and disease progression in high-risk patients with ET/PV. This trial was registered at www.clinicaltrials.gov as #NCT01259856.

Background: Myelofibrosis (MF) is a blood cancer associated with splenomegaly, blood count abnormalities, reduced life expectancy and high prevalence of disease-associated symptoms. Current treatment options for MF are diverse, with limited data on management strategies in real-world practice in the United Kingdom. Methods: The REALISM UK study was a multi-center, retrospective, non-interventional study, which documented the early management of patients with MF. The primary endpoint was the time from diagnosis to active treatment. Discussion: Two hundred patients were included (63% [ n = 126/200] with primary MF; 37% [ n = 74/200] with secondary MF). Symptoms and prognostic scores at diagnosis were poorly documented, with infrequent use of patient reported outcome measures. ‘Watch and wait’ was the first management strategy for 53.5% ( n = 107/200) of patients, while the most commonly used active treatments were hydroxycarbamide and ruxolitinib. Only 5% of patients proceeded to allogeneic transplant. The median (IQR) time to first active treatment was 46 days (0–350); patients with higher risk disease were prescribed active treatment sooner. Conclusion: These results provide insight into real-world clinical practice for patients with MF in the United Kingdom. Despite the known high prevalence of disease-associated symptoms in MF, symptoms were poorly documented. Most patients were initially observed or received hydroxycarbamide, and ruxolitinib was used as first-line management strategy in only a minority of patients. Plain Language Summary Background: Myelofibrosis is a rare blood cancer associated with symptoms that can seriously affect a patient’s daily life, such as enlarged spleen and decreased white and red blood cells. Although several treatments are available for patients with myelofibrosis, it is not clear which ones clinicians use most frequently. Methods: We aimed to review which treatments are usually given to patients with myelofibrosis in the UK, by collecting information from the medical records of 200 patients with myelofibrosis treated in different centres across the UK. Results: The results showed that the symptoms patients experienced were not always written down in the medical records. Similarly, clinical scores based on patient characteristics (which clinicians use to try to predict if a patient will respond to treatment well or not) were also missing from the medical records. Clinicians also rarely asked patients to complete questionnaires that try to measure the impact of myelofibrosis and its treatment on their health. The most common approach for patients with myelofibrosis in the UK was ‘watch and wait’, which over half of patients received. The most common drugs used for treatment were hydroxycarbamide and ruxolitinib; only a very small proportion of patients received a bone marrow transplant. On average, patients waited for 46 days before receiving a treatment, although patients considered to have a more aggressive type of disease received treatment sooner. Conclusion: The results of this study suggest that medical records can be missing key information, which is needed to decide which is the best way to treat a patient with myelofibrosis. They also suggest that clinicians in the UK prefer observation to treatment for a large number of patients with myelofibrosis. This could mean that the approach used for many patients with myelofibrosis does not help them to control symptoms that have an impact on their daily lives.

Ruxolitinib (Jakafi®) is the one approved therapy for myelofibrosis (MF) based on reduction of splenomegaly and symptoms but JAK inhibition has not proven to significantly modify disease progression. There remains the need for novel therapies with distinct modes of action that can improve the patient experience of MF and impact progression. Lysine-specific demethylase, LSD1, is an epigenetic enzyme critical for self-renewal of malignant myeloid cells and differentiation of myeloid progenitors. LSD1 bound to GFI1b permits maturation of progenitors to megakaryocytes and enables their normal function. IMG-7289 (bomedemstat) is an orally available LSD1 inhibitor. In mouse models of myeloproliferative neoplasms (MPN), IMG-7289 reduced elevated peripheral cell counts, spleen size, inflammatory cytokines, mutant allele frequencies, and marrow fibrosis (Jutzi et al. 2018) supporting its clinical development. IMG-7289-CTP-102 is an ongoing, multi-center, open-label study that recently transitioned from a Phase 1/2a dose-range finding study to a Phase 2b study of IMG-7289 administered orally once-daily in adult patients with intermediate-2 or high-risk MF resistant to or intolerant of ruxolitinib. The key objectives are safety, PD, changes in spleen volume (MRI/CT) and total symptoms scores (TSS) using the MPN-SAF instrument. Inclusion criteria included a platelet count ≥100K/μL. Bone marrow (BM) biopsies and imaging studies (both centrally-read) were conducted at baseline and during washout (post-Day 84). The MPN-SAF was self-administered weekly. Phase 1/2a patients were treated for 84 days followed by a washout of up to 28 days. Patients demonstrating clinical benefit could resume treatment for additional 12 week cycles. Dosing was individually tailored using platelet count as a biomarker of effective thrombopoiesis. Patients were started at a presumed sub-therapeutic dose of 0.25 mg/kg/d and up-titrated weekly until the platelet count rested between 50 and 100K/μL. This preliminary analysis includes 20 patients; 18 enrolled in the Phase 1/2a study, 2 in the Phase 2b portion. 50% had PMF, 35% Post-ET-MF, 15% Post-PV-MF. The median age was 65 (48-89) with 70% males. The median baseline platelet count was 197 k/μL (102-1309k/μL). 12 patients (56%) were transfusion-dependent at baseline. Sixty percent were IPSS-classified as high risk, the remainder, intermediate risk-2. 71% had more than 1 mutation of the 261 AML/MPN genes sequenced of which 63% were high molecular risk (ASXL1, U2AF1, SRSF2) mutations; 31% had abnormal karyotypes. Sixteen patients completed the first 12 weeks; 4 patients withdrew, one due to fatigue (Day 33), one for progressive disease (Day 39), one due to physician decision (Day 76), one for an unrelated SAE of cellulitis (Day 83). All patients were up-titrated from the starting dose 0.25 mg/kg to an average daily dose of 0.89 mg/kg ± 0.20 mg/kg, the dose needed to achieve the target platelet count range; 17 achieved the target platelet range in a mean time of 45 days. Of patients evaluable for response after cycle 1 in Phase1/2a (N=14), 50% had a reduction in spleen volume from baseline (median SVR: -14%; -2% to -30%). Further, 79% (N=11) recorded a reduction in TSS (mean change -28%; -13% to -69%); for 21% of patients (N=3), the change was >-50%. Improved BM fibrosis scores at Day 84 were observed in 2/13 patients. Two patients had improvement in transfusion requirements. Plasma IL-8 levels were significantly elevated in 6/14 patients at baseline and dropped in a dose-dependent manner over 21 days in 5/6 patients. The mean duration of treatment is 166 days (14-539) at the census point in this ongoing study. Nineteen patients (95%) reported 358 AEs of which 22 were SAEs. Of the SAEs, 2 were deemed by investigators as possibly related: painful splenomegaly and heart failure. There have been no safety signals, DLTs, progression to AML, or deaths. This is the first clinical study of an LSD1 inhibitor in patients with MPNs. Once-daily IMG-7289 was well-tolerated in a heterogeneous population of patients with advanced MF and limited therapeutic options. Despite under-dosing and slow dose escalation, IMG-7289 improved symptom burdens in most patients and modestly reduced spleen volumes in a subset of patients. The Phase 2b 24-week expansion study with more aggressive dosing aimed at preserving safety and enhancing efficacy is open for enrollment in the US, UK and EU. Figure Disclosures Pettit: Samus Therapeutics: Research Funding. Gerds:Imago Biosciences: Research Funding; Celgene Corporation: Consultancy, Research Funding; CTI Biopharma: Consultancy, Research Funding; Roche: Research Funding; Sierra Oncology: Research Funding; Incyte: Consultancy, Research Funding; Pfizer: Consultancy. Yacoub:Hylapharm: Equity Ownership; Agios: Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Seattle Genetics: Honoraria, Speakers Bureau; Incyte: Consultancy, Honoraria, Speakers Bureau; Ardelyx: Equity Ownership; Cara: Equity Ownership; Dynavax: Equity Ownership. Watts:Pfizer: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Bradley:AbbVie: Other: Advisory Board. Shortt:Celgene: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Astex: Research Funding; Amgen: Research Funding; Gilead: Speakers Bureau; Takeda: Speakers Bureau. Natsoulis:Imago BioSciences: Consultancy, Equity Ownership. Jones:Imago BioSciences: Employment, Equity Ownership. Talpaz:Samus Therapeutics: Research Funding; Novartis: Research Funding; Incyte: Research Funding; Constellation: Research Funding; Imago BioSciences: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; CTI BioPharma: Research Funding. Peppe:Imago BioSciences: Employment, Equity Ownership. Ross:Novartis: Consultancy, Honoraria, Research Funding; Celgene: Honoraria, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees. Rienhoff:Imago Biosciences: Employment, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties.

Background: Lysine-specific demethylase-1 (LSD1) is an activity critical for the self-renewal of malignant myeloid cells and maturation of megakaryocytes, cells central to the pathogenesis of MF. Bomedemstat is an orally active LSD1 inhibitor that in mouse models ameliorated the hallmarks of MPNs and improved survival (Kleppe et al. 2015; Jutzi et al. 2018). Aims: IMG-7289-CTP-102 is an ongoing, global, open-label Phase 2 study evaluating bomedemstat dosed QD in MF patients (NCT03136185). Key eligibility criteria include patients intolerant, refractory, resistant, or inadequately controlled by approved therapy, and platelet count ≥100 x 109/L. Key objectives are safety and reduction of spleen volume (SVR) by MRI/CT and total symptoms scores (TSS) using the MPN-SAF instrument. Methods: Serial bone marrow (BM) biopsies and imaging studies are read centrally. 261 genes are serially sequenced to quantify changes in the allelic frequencies of mutations (MAF) and identify new mutations. The starting dose is 0.6 mg/kg/d titrating, as needed, to a platelet count of 50-75x109/L. Results: At 89 patients, the study is now fully enrolled: 46% primary MF, 33% post-essential thrombocythaemia-MF, 21% post-polycythaemia vera-MF. Median age is 68 (35-88) with 52% males. Prior treatment with ruxolitinib was reported in 83% (74/89); 46% had also received at least 1 additional treatment. 30% of patients (27/89) had received ≥1 RBC transfusion prior to dosing. By IPSS, 53% were high-risk, 40% int.-2, and 7% int.-1. At screening (N=103), sequencing to a mean depth of >1000 bp, JAK2 was mutated in 69%, CALR in 21%, MPL in 6%; 59% had ≥2 mutations of which 71% were high-molecular risk mutations in ASXL1, IDH1/2, EZH2, U2AF1, TP53 and/or SRSF2. At data cutoff (3 Feb 2022), the median duration of treatment is 28 weeks (2-131). Of patients for whom TSS data is available at 24 weeks in those with baseline values ≥20, 72% (18/25) had a reduction in TSS; 24% (6/25) reported a ≥50% reduction. Of patients evaluable for SVR (N=50), 64% had a reduction in spleen volume from baseline; in 28%, SVR was ≥20%. Of evaluable patients (N=41), 90% had stable (∆ <±1.0 g/dL) or improved (≥1.0 g/dL) hemoglobin. Of patients with BM fibrosis scoring post-baseline (N=52), 31% improved by 1 grade and 50% were stable. CCL5 and S100A8/A9 cytokines were elevated at baseline in 50% (16/32) and 78%, respectively; at Day 84, 81% and 68%, respectively, showed reductions of at least 10% and of those, 100% (CCL5) and 47% (S100A8/A9) normalized. In follow-up sequencing at around Week 24, of 60 mutant alleles in 32 patients, the mean MAF fell by 39% in 48%. JAK2 MAFs fell by 31% [SD 5%] in 46% (N=24); ASXL1 MAFs fell 40% in 71%. Clones with JAK2 and/or ASXL1 mutations were most affected. No new mutations have been identified and no patient has transformed to AML. The most common non-hematologic AEs reported by patients was dysgeusia in 36% (32/90) and diarrhoea in 34% (31/90). All dysgeusia events were grade 1/2 and 1 led to treatment discontinuation. Of 14 related SAEs, 4 were Grade 2, 9 Grade 3 and 1 Grade 4 (thrombocytopenia). Twenty-nine patients remain on bomedemstat. Early terminations due to AEs occurred in 18 (20%) patients (9 related to bomedemstat), and 13 discontinued for other reasons. There have been no safety signals, DLTs, or deaths related to drug. Summary/Conclusion: In patients with advanced MF, bomedemstat alone had an acceptable tolerability profile, relieved symptoms, reduced spleen volume and mutation burden while improving fibrosis and anemia without safety signals.

Abstract The myeloproliferative neoplasms (MPN) polycythaemia vera (PV) and essential thrombocythaemia (ET) are associated with significant symptom burden with impaired quality of life (QoL). In the MAJIC study patients refractory/intolerant to hydroxycarbamide (HC), were randomised to treatment with ruxolitinib (Rux) or best available therapy (BAT). In this unique and comprehensive analysis we explore quality of life (QoL) outcomes in the MAJIC study using the MPN10 Self-Assessment Form (SAF) in particular using this unique dataset to explore for the first time differences between JAK2 ET vs PV, and JAK2 ET vs CALR ET at baseline and 12 months of therapy with Rux or BAT. Methods 306 patients were randomised, (190, PV and 116 ET arm) and followed for 5 years, no cross over was permitted. MPN10 SAF was assessed at baseline, 2, 4, 8 and 12 months in both arms. Equal variance two sample t-tests were used to test differences between diagnosis groups (JAK2 ET vs PV & JAK2 ET vs CALR ET) in baseline scores and 12-month change from baseline scores, here negative change from baseline indicates improvement. QoL data was also collected using MD Anderson Symptoms Inventory (MDASI) and 5 level EQ5D at the same time points as the MPN10 SAF. Results JAK2 ET vs PV 110 participants with JAK2 mutation were included in the analysis for JAK2 ET vs PV. 81 (74%) had PV and 29 (26%) had JAK2 ET; 44 patients (54.3%) with PV and 18 (62.1%) patients with ET were randomised to Rux, and 37 (45.6%) patients with PV and 11 (37.9%) with ET to BAT. Baseline mean total symptom score (TSS) was similar (JAK2 ET: 18.9. SD 18.4 and PV: 23.7, SD 17.81 (p=0.27). Mean for pruritus was 1.9 (SD 2.47) in JAK2 ET and 3.5 (SD 2.99) in PV (p=0.03). Other baseline scores were comparable: mean scores for fatigue was 3.3 (SD 3.07) for JAK2 ET vs 4.7 (SD 2.68) for PV, for early satiety was 2.6 (SD 2.78) for JAK2 ET vs 2.1 (SD 2.40) for PV, for abdominal discomfort 3.0 (SD 3.34) for JAK2 ET vs 2.0 (SD 2.78) for PV, for inactivity was 2.4 (SD 2.86) for JAK2 ET vs 3.2 (SD 2.72) for PV; for concentration problems was 2.2 (SD 2.51) for JAK2 ET vs 2.9 (SD 3.11) for PV, for night sweats was 1.6 (SD 2.20) for JAK2 ET vs 2.1 (SD 2.66) for PV, for bone pain was 1.8 (SD 2.97) for JAK2 ET vs 2.0 (SD 2.86) for PV, for fever was 0.5 (SD 1.46) for JAK2 ET vs 0.5 (SD 1.70) for PV and for weight loss was 0.3 (SD 0.73) for JAK2 ET vs 1.0 (SD 2.15) for PV (p>0.05 for all). Concerning change at 12 months, mean (SD) change in TSS was -0.5 (SD 10.86) for JAK2 ET (n=21) vs -0.8 (SD 13.32) for PV (n=66) (P=0.93). Mean for individual symptom scores at 12 months were also not significantly different between the two phenotypic disease group (P>0.05 for all parameters). (Fig 1, top panels). CALR vs JAK2 ET Exploring symptoms for CALR vs JAK2 ET: 45 patients were included; 9/16 (56.3%) CALR and 18/29 (62.1%) JAK2 patients were assigned to Rux (p=0.70). 10/16 (62.5%) CALR ET and 19/29 (65.5%) JAK2 ET. Baseline mean total symptom score (TSS) was similar (JAK2 ET: 18.9, SD 18.4 and CALR ET: 18.8, SD 16.99 (p=0. 0.98). All other baseline scores were comparable in this intolerant/ refractory population (p>0.05 for all. Concerning change at 12 months, mean (SD) change in TSS was -0.5 (SD 10.86) for JAK2 ET vs -2.8 (SD 9.96) for CALR ET (P=0.56). Mean for individual symptom scores at 12 months were also not significantly different between the two phenotypic disease group (P>0.05 for all parameters); the mean change in night sweats approached but did not reach significance similar (JAK2 ET: 0.2 (SD 1.89) and CALR ET: 1.8 (SD 3.07) (p=0. 0.06). (Fig 1, lower panels). Preliminary analysis of the MDASI and EQ5D-5L data at baseline and at 12 months shows similar results and will be presented. Conclusion This first analysis of its kind compared the symptom burden and other parameters of QoL of patients with PV and ET, resistant/intolerant to HC shows that with the exception of pruritus at baseline there were no substantial differences between JAK2 ET or PV. Equally changes in symptom burden across 12 months did not substantially differ between JAK2 ET or PV. A second analysis of JAK2 vs CALR ET also failed to show substantial differences. This data should be expanded in a larger cohort but supports a symptom continuum of JAK2 ET and PV and also JAK2 vs CALR ET. Figure 1 Figure 1. Disclosures Mead: Abbvie: Consultancy, Honoraria; Celgene/BMS: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Speakers Bureau. Yap: Faron Pharmaceuticals: Honoraria; Celgene: Honoraria. Knapper: Novartis: Consultancy, Research Funding, Speakers Bureau; Astellas: Consultancy, Speakers Bureau; Jazz Pharmaceuticals: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau. Drummond: CTI: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Mesa: Pharma: Consultancy; CTI: Research Funding; Abbvie: Research Funding; Genentech: Research Funding; Gilead: Research Funding; AOP: Consultancy; Incyte Corporation: Consultancy, Research Funding; Sierra Oncology: Consultancy, Research Funding; Novartis: Consultancy; La Jolla Pharma: Consultancy; Samus: Research Funding; Promedior: Research Funding; Constellation Pharmaceuticals: Consultancy, Research Funding; Celgene: Research Funding; CTI: Research Funding. Scherber: Incyte Corporation: Current Employment, Current holder of stock options in a privately-held company. McMullin: Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan: Research Funding, Speakers Bureau; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Other: clinical trial support, Research Funding. Harrison: CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Promedior: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead Sciences: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Sierra Oncology: Honoraria; Constellation Pharmaceuticals: Research Funding; Incyte Corporation: Speakers Bureau; Geron: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Galacteo: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Abstract MAJIC is a phase II trial of Ruxolitinib (RUX) vs Best Available Therapy (BAT) in polycythemia vera (PV) patients with resistance/intolerance to Hydroxycarbamide (HC). This analysis involved a primary comparison between the RUX and BAT arms for quality of life (QOL) durability over 60 months, with secondary comparisons of best QOL response within first year in complete hematologic responders (CR) vs a group of partial or no response (NR/PR). This is a unique analysis due to cross-over nature of prior studies. Patients were stratified by treatment arm with either RUX or BAT. QOL was assessed over 0-60 months using the Myeloproliferative Neoplasms Symptom Assessment Form (MPN-SAF). MPN-SAF Total Symptom Score (TSS) was computed as the average of all completed items multiplied by 10 (scale 0-100, higher score represents higher symptom burden). Estimates of change from baseline and between arm differences in change by timepoint were made using a linear mixed model with compound symmetry covariance structure, which included covariates for categorical time point, treatment arm, and the interaction between time point and treatment arm. The difference between arms in proportion of patients with best post-baseline TSS response of 50% or greater was testing using a Chi-square test. In this study, 147 of the 190 trial patients had started treatment and completed at least their baseline assessment and were included in the analysis with 39 patients completing through 60 months. Groups were comprised of 76 patients in the RUX group (31 females, 45 males, mean age 64.2 [SD 11.4]) and 71 patients in the BAT group (29 females, 42 males, mean age 64.6 [SD 11.5]). Symptom scores at baseline were similar between arms, with MPN-SAF weight loss the only statistically significant difference (BAT 0.7 [SD 1.71] vs RUX 1.7 [SD 2.83], p=0.02). Significant, durable improvements in TSS were noted in RUX patients with symptom improvements lasting a mean of 52 months. BAT patients experienced a worsening of their symptom burden with improvements back to baseline notable at 56 months (Figure 1). MPN-SAF TSS there were significant differences between treatment arms in change from baseline to months 2-32, 44, and 48 (all p<0.05). In all months the trend was in the direction of larger improvement in the RUX arm, with the point estimate for difference ranging from 2.1 (at month 56) to 11.3 (at month 4) with most prominent changes occurring between months 2 and 32. Of the 80 patients with MPN-SAF TSS scores at baseline and at least one post-baseline timepoint, 13/41 (31.7%) BAT and 24/39 (61.5%) RUX patients had TSS reduction of 50% or greater in at least one time point, which was statistically significant (p=0.008). In regard to specific symptoms, there was a statistically significant between arm difference seen in over 5 timepoints for fatigue, early satiety, night-sweats, itching, bone pain, and weight loss. Comparing MPN-SAF TSS in Complete Response (CR n=51) vs Non-Responder/Partial Responders (NR/PR) (n=96) there was no difference at baseline in any of the measures at any time point. A possible limitation of this study is the potential for bias in which the patients who were lost to follow up could be different then the patients who remained in the study through all 60 months which would affect generalization, particularly at time points at the later years. The novel findings of this investigation demonstrate that Ruxolitinib ameliorates the PV symptom burden in patients resistant or intolerant to HC in a robust durable manner over at least four years, while patients receiving BAT have worsening of their symptom burden over this same time period. Figure 1 Figure 1. Disclosures Mead: Novartis: Consultancy, Honoraria, Speakers Bureau; Celgene/BMS: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria. Yap: Celgene: Honoraria; Faron Pharmaceuticals: Honoraria. Scherber: Incyte Corporation: Current Employment, Current holder of stock options in a privately-held company. Knapper: Novartis: Consultancy, Research Funding, Speakers Bureau; Astellas: Ended employment in the past 24 months, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Jazz: Consultancy, Speakers Bureau. Drummond: Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; CTI: Membership on an entity's Board of Directors or advisory committees. McMullin: Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Other: clinical trial support, Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan: Research Funding, Speakers Bureau. Mesa: CTI: Research Funding; AOP: Consultancy; Celgene: Research Funding; Novartis: Consultancy; Gilead: Research Funding; Pharma: Consultancy; Promedior: Research Funding; Constellation Pharmaceuticals: Consultancy, Research Funding; CTI: Research Funding; Samus: Research Funding; Sierra Oncology: Consultancy, Research Funding; Genentech: Research Funding; Incyte Corporation: Consultancy, Research Funding; Abbvie: Research Funding; La Jolla Pharma: Consultancy. Harrison: CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead Sciences: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Geron: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Constellation Pharmaceuticals: Research Funding; Galacteo: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte Corporation: Speakers Bureau; Sierra Oncology: Honoraria; Promedior: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AOP Orphan Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Keros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau.

British Journal of HaematologyVolume 193, Issue 3 p. 481-481 Images In Haematology COVID-19-associated oxidative damage to red blood cells Muhammad Khakwani, Corresponding Author Muhammad Khakwani [email protected] orcid.org/0000-0002-1097-2730 University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this authorClaire Horgan, Claire Horgan University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this authorJoanne Ewing, Joanne Ewing University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this author Muhammad Khakwani, Corresponding Author Muhammad Khakwani [email protected] orcid.org/0000-0002-1097-2730 University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this authorClaire Horgan, Claire Horgan University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this authorJoanne Ewing, Joanne Ewing University Hospitals Birmingham NHS Foundation Trust, Birmingham, UKSearch for more papers by this author First published: 11 January 2021 https://doi.org/10.1111/bjh.17317Citations: 9Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume193, Issue3May 2021Pages 481-481 RelatedInformation

The present study describes a patient aged 70 with very high-risk AML who successfully received a nonmyeloablative matched unrelated donor allograft shortly following SARS-CoV-2 infection, which manifested with mild cough, interstitial abnormalities on chest CT, and pancytopenia with profound bone marrow biopsy histological alterations. In parallel, our study provides bone marrow biopsy data in a series of contemporary patients with serious haematological diseases who had a bone marrow biopsy performed within two weeks of PCR confirmation of SARS-CoV-2 infection. This study is notable because there are no published data describing the bone marrow biopsy changes observed in patients with haematological malignancies and SARS-CoV-2 infection. Finally, it is suggested that nonmyeloablative hematopoietic stem cell transplantation for very high-risk haematological malignancies can be successfully performed following recovery from SARS-CoV-2 infection.

Background Myeloproliferative neoplasms (MPN) commonly result from mutations in genes encoding the kinase JAK2 or the multi-functional protein CALR. In preclinical studies, estrogen receptor alpha (ERα) modulation restores normal apoptosis in JAK2V617F hematopoietic progenitors (HSPCs). Use of selective ER modulators (SERM) such as tamoxifen may permit the molecular reduction of MPNs. Methods TAMARIN is a Trials Acceleration Programme, Phase II, multicentre, single arm A'herns design clinical trial assessing tamoxifen's safety and activity in reducing molecular markers of disease burden in MPN male patients aged ≥60 years and post-menopausal female patients with stable blood counts, no history of thrombosis and ≥20% mutated JAK2V617F, CALR 5bp insertion or CALR 52bp deletion. Based on tamoxifen's safety profile in ER+ breast cancer, an oral dose of 20 mg once daily was initially given and progressively escalated to 40 mg, in addition to standard cytoreductive therapy (excluding treatments known to lower allele burden eg interferon). Mutant allele burden was measured after 12 and 24 weeks (w) of treatment. The A'herns success criteria required the primary outcome (>50% reduction in allele burden at 24w) be observed in ≥3 patients (Barosi Leuk. 2015). Patient blood (baseline, 12 and 24w) samples were collected and CD34+ HSPCs were isolated in a subset for RNA-Seq, which was also performed on HEL and UKE-1 JAK2V617F-mutated human cell lines treated with tamoxifen/vehicle. Apoptosis and oxidative phosphorylation (OXPHOS) were measured in SERM-treated cell lines for confirmation. Results and Discussion 38 patients (37% essential thrombocythaemia (ET), 29% polycythaemia vera (PV), 16% primary myelofibrosis (PMF), 13% post-PV MF and 5% post-ET MF) were recruited over 112w. 33 patients completed ≥24w of tamoxifen treatment, 1 was untreated, 1 discontinued following an unprovoked thrombotic event and 3 discontinued due to toxicity. 4 patients achieved the primary outcome and 6 additional patients met the secondary outcome (≥25% reduction)(A-B). Responders included 4 JAK2V617F PV males, a JAK2V617F PMF female and ET patients of both genders carrying JAK2V617F, CALRdel52 or CALRins5 mutations. 4 patients remain on trial treatment beyond 48w as they are considered to be deriving clinical benefit. Two grade 3 adverse events unrelated to tamoxifen, as well as 1 superficial thrombophlebitis and 1 deep vein thrombosis (grade 2) occurred on study. HSPC transcriptome seggregates responders and non-responders perfectly at baseline (C), suggesting a potential predictive signature of response. Pathway analysis of differentially-expressed genes shows enrichment of myeloid differentiation and hormone-dependent transcriptional complex assembly in responders at baseline. In contrast, chromosome segregation, DNA replication, and chromosome condensation pathways are enriched in non-responders. Gene-set enrichment analysis (GSEA) reveals increased apoptosis and oxidative phosphorylation (OXPHOS) signatures in responders at baseline (D). Upregulated genes in responders are associated with H3K4me1 modification whilst genes upregulated in non-responders are associated with H3K9me3, suggesting the possibility that chromatin modifications account for tamoxifen sensitivity. 24w after treatment, OXPHOS and ROS pathways are downregulated in responder HSPCs (E) but upregulated in non-responders (F), suggesting striking differences in the metabolism of HSPCs in both groups and/or the eradication of sensitive HSPCs in responders. Reduced OXPHOS pathways and deregulated expression of unfolded protein response (UPR) genes were confirmed in HEL and UKE-1 cells. In fact, tamoxifen induces dose-dependent apoptosis in HEL and UKE-1 cells, where serum deprivation or UPR inducers sensitize resistant cells to tamoxifen-induced apoptosis, which is associated with decreased OXPHOS and energy (ATP) production. Conclusions These results demonstrate the safety and activity of tamoxifen in reducing mutant allele burden in a subset of MPN patients who could be prospectively identified based on their transcriptomic signature at baseline. Tamoxifen can induce apoptosis of human JAK2V617F or CALR mutated HSPCs through metabolic and transcriptional effects. These results advocate for future studies to test the effects of SERMs in MPN with careful consideration of thrombotic risk. Disclosures Harrison: Roche: Honoraria; Novartis: Honoraria, Research Funding, Speakers Bureau; Janssen: Speakers Bureau; AOP Orphan Pharmaceuticals: Honoraria; Promedior: Honoraria; Shire: Honoraria, Speakers Bureau; CTI Biopharma Corp: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding, Speakers Bureau; Sierra Oncology: Honoraria; Gilead Sciences: Honoraria, Speakers Bureau; Incyte Corporation: Speakers Bureau. Mead:CTI: Consultancy; Gilead: Consultancy; Celgene/BMS: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding; Novartis: Consultancy, Honoraria, Other: travel, accommodations, expenses, Research Funding, Speakers Bureau; Abbvie: Consultancy. Knapper:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Ewing:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene/BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. McMullin:Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy; Celgene: Consultancy; Abbvie: Membership on an entity's Board of Directors or advisory committees. Narayanan:Novartis: Other: Educational support to attend conferences; MSD: Speakers Bureau; Celgene: Other: Educational support to attend conferences; Alexion: Speakers Bureau; Takeda: Other: Educational support to attend conferences. Milojkovic:Incyte: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria. Drummond:Jazz: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Blueprint Medicine Corporation: Research Funding; Astellas: Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. OffLabel Disclosure: Tamoxifen is a selective estrogen receptor modulator frequently used in estrogen receptor-positive breast cancer.

Covid-19 has emerged as a global threat that has claimed millions of lives until now. Haematological manifestation as an initial presentation of this deadly virus is not frequently reported in the literature. We hereby report a case series of asymptomatic patients with severe thrombocytopenia which was later found to be Covid induced.

Background Interferons are recognized as active agents in the treatment of patients with high risk essential thrombocythemia (ET) or polycythemia vera (PV), both in the upfront setting as well as beyond. Several trials have shown high rates of hematologic and molecular responses with the use of interferons, however, data on direct comparison of interferon activity in patients with early disease in comparison to patients refractory or resistant to prior therapies, such as hydroxyurea (HU) are lacking. We conducted a controlled analysis of the activity of pegylated interferon alfa-2a (PEG) in two prospective parallel clinical trials conducted in these two unique patient populations. Methods The MPD-RC 111 (NCT01259817) was an international, multicenter, phase 2 open-label clinical trial that evaluated PEG therapy in patients with high risk PV and high-risk ET who were either refractory or intolerant (R/I) to HU by modified ELN criteria. The MPD-RC 112 trial (NCT01258856) enrolled patients with high risk ET/PV who were treatment-naïve (TN) (HU <3 months) and randomized them (1:1) to PEG or HU. All patients randomized to PEG were included in this analysis. Both protocols were conducted concurrently at the MPD-RC member institutions and utilized a similar primary endpoint of overall response rate (complete and partial response rates) by ELN Criteria at 12 months confirmed by the same blinded central review committee. Both studies utilized the same PEG starting dose of 45 mcg weekly and was titrated for response to a maximum of 180 mcg weekly. Secondary endpoints included safety information, impact on disease biomarkers, bone marrow (BM) response, and quality of life data. Results Patients ET: 39 TN and 65 R/I ET patients were available for this analysis. Median disease duration was 2.9 months in TN and 37.3 months in R/I patients. Baseline characteristics and demographics were similar in the two cohorts except lower baseline hemoglobin level in RI patients. (Table1A) PV: 43 TN and 50 R/I PV patients were included. Median disease duration was 2.5 months in TN and 54.8 months in R/I patients. Baseline characteristics only differed by lower frequency of phlebotomy rate in R/I patients. (Table1B) Baseline symptoms scores and quality of life were similar in TN and RI groups (Table 2) Response ET: CR/PR/ORR at 12 months were observed in 43.1%/26.2%/69.2% in R/I ET patients and in 43.6%/25.6%/69.2% in TN ET patients (p=0.99 for ORR). (Table 3, Figure 1) PV: CR/PR/ORR at 12 months were observed in 22%/38%/60% in R/I PV patients, and in 27.9%/58.1%/86% in TN PV patients (p=0.005 for ORR). (Table 3, Figure 1) Safety PEG was equally well tolerated throughout both treatment groups with treatment discontinuation due to adverse events occurring in 14.6% in TN patients and 13.9% in R/I patients. The mean (SD) dose of PEG was 102.7 (52.3) mcg in R/I ET patients and 128.7mcg (46.4) in R/I PV patients. For TN patients, mean dose was 85.7mcg (59.7) in ET and 93.5 mcg (44.0) in PV. Adverse events were consistent with historic reports of PEG use and the distribution of events was similar in R/I and TN patients. (Table 4) Conclusion This intention to treat response analysis included TN and R/I ET and PV patients with balanced baseline characteristics who received prospective therapy with PEG. Patients with ET had a higher overall response rate at 12 months that was equivalent in patients who were treatment-naïve and in patients who were intolerant or refractory to HU. By contrast, patients with PV who were treatment-naïve had a higher ORR than patients those intolerant or refractory to HU. We conclude that treatment with PEG is an effective therapeutic option both treatment naïve PV and ET as well as those previously treated with HU, however PEG as a second line agent is especially effective in ET patients. Disclosures Yacoub: Hylapharm: Equity Ownership; Agios: Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Seattle Genetics: Honoraria, Speakers Bureau; Incyte: Consultancy, Honoraria, Speakers Bureau; Ardelyx: Equity Ownership; Cara: Equity Ownership; Dynavax: Equity Ownership. Mascarenhas:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Roche: Consultancy, Research Funding; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Pharmaessentia: Consultancy, Membership on an entity's Board of Directors or advisory committees; CTI Biopharma: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Research Funding; Promedior: Research Funding; Merus: Research Funding. Mesa:AbbVie: Research Funding; Samus: Research Funding; Incyte: Research Funding; Sierra Onc: Consultancy; Genotech: Research Funding; Promedior: Research Funding; Novartis: Consultancy; Celgene: Research Funding; CTI Biopharma: Research Funding; La Jolla Pharma: Consultancy. Rampal:Agios, Apexx, Blueprint Medicines, Celgene, Constellation, and Jazz: Consultancy; Constellation, Incyte, and Stemline Therapeutics: Research Funding. Silver:PharmEssentia: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. McMullin:Daiko Sanyo: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Speakers Bureau; Italopharma: Membership on an entity's Board of Directors or advisory committees. Ewing:Novartis: Honoraria, Other: Meeting attendance sponsorship ; Bristol Myers-Squibb: Other: Meeting attendance sponsorship . O'Connell:Astex: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genentech: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Shionogi: Membership on an entity's Board of Directors or advisory committees. Mead:Bristol Myers-Squibb: Consultancy; Novartis: Consultancy, Honoraria, Other: Travel/accommodation expenses, Research Funding, Speakers Bureau; CTI: Honoraria, Research Funding; Celgene: Consultancy, Research Funding; Pfizer: Consultancy. De Stefano:Alexion: Consultancy, Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau; Amgen: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau. Baer:Astellas: Research Funding; Al Therapeutics: Research Funding; Abbvie: Research Funding; Incyte: Research Funding; Forma: Research Funding; Kite: Research Funding; Takeda: Research Funding. Vannucchi:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees; Italfarmaco: Membership on an entity's Board of Directors or advisory committees; CTI BioPharma: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Kremyanskaya:La Jolla: Consultancy; Incyte, Celgene, Constellation, Protagonist.: Research Funding. Hexner:novartis: Research Funding. Rambaldi:Amgen: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Research Funding, Speakers Bureau; Italfarmaco: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Research Funding, Speakers Bureau; Omeros: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Speakers Bureau; Gilead: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Roche: Membership on an entity's Board of Directors or advisory committees, Other: travel support, Research Funding, Speakers Bureau; Jazz: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau, travel support. Ritchie:Genentech: Other: Advisory board; Tolero: Other: Advisory board; agios: Other: Advisory board; Pfizer: Other: Advisory board, travel support; Celgene: Other: Advisory board; Jazz Pharmaceuticals: Research Funding; Celgene, Novartis: Other: travel support; AStella, Bristol-Myers Squibb, Novartis, NS Pharma, Pfizer: Research Funding; Ariad, Celgene, Incyte, Novartis: Speakers Bureau; Celgene, Incyte, Novartis, Pfizer: Consultancy. Kiladjian:Novartis: Honoraria, Research Funding; AOP Orphan: Honoraria, Research Funding; Celgene: Consultancy. Harrison:Promedior: Honoraria; Incyte: Speakers Bureau; Sierra Oncology: Honoraria; Celgene: Honoraria, Speakers Bureau; Janssen: Speakers Bureau; CTI: Speakers Bureau; AOP: Honoraria; Shire: Speakers Bureau; Roche: Honoraria; Gilead: Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau. Hoffman:Merus: Research Funding. OffLabel Disclosure: Pegylated Interferon Alfa-2a for in Patients with Polycythemia Vera or Essential Thrombocythemia