Harrison, Claire

In 2005, the description of the JAK2V617F mutation for the first time provided a molecular key to enable more rapid diagnosis and target for novel therapeutics in the myeloproliferative neoplasms. In 2007, the first-in-class agent INC18424, ruxolitinib, JAKafi, or JAKAVI was first tested in patients with intermediate-risk 2 or high-risk myelofibrosis regardless of whether they possessed the JAK2V617F mutation. Patients treated with this agent had major reduction in splenomegaly as well as impressive reduction, and in some cases resolution, of symptoms. This study was followed by the two Controlled Myelofibrosis Study with Oral JAK Inhibitor Therapy (COMFORT) trials (the first-ever phase III trials in myelofibrosis), which confirmed results in these aspects were superior to either placebo or standard care, and updated results show a survival advantage with this therapy. This paper discusses these results and data from other JAK inhibitors while speculating on the future of these therapies. It also reflects on the fact that the true targets and agents' mode of action are uncertain. Unlike targeted therapy for chronic myeloid leukemia (CML), these agents do not deliver molecular remission, and it is not clear whether their predominant benefit is mediated via JAK2, JAK1, or both. Nonetheless, the advent of the JAK inhibitor is a welcome advance and has made a dramatic improvement to the therapeutic landscape of these conditions.

Abstract Philadelphia-negative Myeloproliferative Neoplasms (MPN), including Polycythemia Vera (PV), Essential Thrombocythemia (ET), Myelofibrosis (Primary [PMF] and secondary to PV and ET [PPV-, PET-MF] and unclassified MPN (U-MPN), are associated with an increased risk of venous thrombosis in unusual sites, such as splanchnic vessels (SVT). SVT can lead to complications such as portal hypertension, esophageal and gastric varices, ascites,hepatic failure and biliopathy. According to a meta-analysis MPN is the underlying cause of portal vein thrombosis (PVT) in 31.5% and Budd Chiari syndrome (BCS) in 40.9% of cases (Smalberg, 2012); a more in-depth analysis of clinical characteristics and evolution of MPN-associated SVT has been hampered by heterogeneity of cohorts comprising small number of cases. We conducted a retrospective multicenter study in patients (pts) with SVT associated with WHO2008-diagnosed MPN, with the aim to describe patient characteristics, disease course and prognostic factors with potential implications for clinical practice. Data were collected from 16 international hematologic centers in the framework of the Italian AGIMM and the IWG-MRT groups. We collected 519 cases of pts with PVT, splenic or mesenteric vein thrombosis (75.1%) and BCS (24.9%) associated with MPN. We used as comparator a cohort of 1686 controls (Ctr) represented by MPN without (w/o) SVT: 741 ET (43.9%), 684 PV (39.7%), 261 PMF (15.5%). Frequency of MPN associated with SVT was 37.8% ET (n=196), 36.8% PV (n=191), 15.4% MF (n=80), 10% U-MPN (n=52). Median follow-up was 89.9 months (mo) (range 0.5-430). For SVT vs Ctr group females were 54.5% vs 44.4% in PV (P=0.001), 68.4 vs 63.5% (p=0.13) in ET, 63.7% vs 29.1% in PMF (p<0.0001); median age at MPN diagnosis (dg) was 43.5 yr (range 12-90) vs 60.6 yr (range 12-93) (p<0.0001). Age at SVT dg was 44 yr (range 15-85). In 240 cases (46.7%) MPN and SVT dg were coincident, in 121 (23.6%) SVT occurred before MPN dg (median 26 mo, range 4-307) and in 153 (29.8%) during MPN follow up (median 68 mo, range 4-362). JAK2V617F mutation was found in 94% PV vs 94% in Ctr, 84% vs 61% ET (p<0.0001), 88.1% vs 68% PMF (p=0.006) and in 93% U-MPN. Erythropoietin-independent colonies (EEC) were evaluated in 111 SVT pts and found in 80 (72%), accounting for 38/48 PV (79%), 31/44 ET (70.5%), 9/12 PMF (75%) and 2/7 U-MPN (28.6%). At dg, SVT PV pts had lower hemoglobin levels than Ctr: median was 17.4 g/dL vs 18.5 g/dL (p<0.0001) in male, 16.9 g/dL vs 17.7 g/dL (p=0.0006) in female. A co-existing thrombophilic status was found in 38.5% SVT vs 11.8% of Ctr (p<0.0001). Recurrent SVT occurred in 12.2% of pts with a rate of 1.6% person/year (CI 1.2-2.1); risk of venous thrombosis other than SVT was increased in SVT group vs Ctr (p=0.02), with no difference for arterial thrombosis. Hemorrhage was more frequent in SVT group (32%) vs Ctr (7.2%)(p<0.0001), mainly related to esophageal varices, which were present in 66.9% of SVT pts. There was no difference in evolution to MF and acute leukemia (AL) for PV and ET pts with and w/o SVT, while risk of AL was lower in MF with SVT (p<0.00001). Overall survival was shorter in ET pts with SVT vs Ctr (p<0.0001). In PMF survival was better in SVT group (p<0.00001) and was associated with a higher proportion of SVT pts in lowest risk categories: IPSS low 65%, intermediate-1 20%, intermediate-2 10% and high 5% compared with 15%, 34%, 25% and 26% in Ctr group. At last FU, 79/519 pts (15.2%) had died; causes of death were evolution to AL (15.4%), other cancers (13.8%), disease progression without AL (10.8%), SVT (10.8%), hepatic failure and venous thrombosis other than SVT (7.7% each), heart failure and arterial thrombosis (6.2% each), hemorrhage (5.5%), renal failure and infection (4.6% each). Therapy after SVT included anticoagulation in 77%, antiaggregant in 21.2% and combination in 1.8%; 70% received cytotoxic drugs; 12.4% were treated with transjugular porto-systemic shunt. Beta blocker therapy was used in 48.5% of pts and correlated with improved survival (p=0.041) MPN associated with SVT correlated with younger age and female sex and might antedate the clinical phenotype in a quarter of the patients. MPN-associated SVT equally affected PV and ET, was more likely to occur in the presence of JAK2V617F or underlying thrombophilia and predicted recurrent venous but not arterial thrombosis. The apparent association of SVT with better or worse prognosis in PMF and ET, respectively, requires further investigation. Disclosures No relevant conflicts of interest to declare.

Abstract Background: Thrombotic and hemorrhagic complications are commonly encountered in uncontrolled essential thrombocythemia (ET). Both anagrelide and hydroxyurea (HU) have proven efficacious in cytoreduction as well as reducing these events and remain first line therapy for most high-risk ET patients. Independent of their role in risk-reduction, little is known about how these therapies impact patient symptomatology or quality of life. In this study, we compared the clinical and symptomatic profiles of ET patients receiving HU or anagrelide against patients with no previous experience with these agents. Methods: Data was assessed from a prospectively collected international database of ET patients in which demographics, disease features, and ET symptoms utilizing the myeloproliferative neoplasm symptom assessment form (MPN-SAF; Scherber et al, 2011). The MPN-SAF includes the patient's perceptions of common MPN-related symptoms and overall quality of life (QOL) on a 0 (absent) to 10 (worst imaginable) scale. Total symptom score (TSS) was computed based on symptom items using the published scoring algorithm on a 0 (all reported symptoms absent) to 100 (all reported symptoms worst imaginable) scale. ET risk scores were calculated using the IPSET scoring algorithm (Passamonti 2012). Thrombocytopenia was defined as a platelet count <100 x 10(9)/L, anemia was defined as hemoglobin<10 g/dL and leukopenia was defined as a white blood cell count <4.0 x 10(9)/L. Associations between the MPN-SAF individual symptoms were investigated using chi-square test for categorical data and ANOVA F-test for continuous variables. Results Hydroxyurea vs. HU Naive A total of 402 ET patients with active HU use were compared to 392 ET patients with no history of HU use. Patients using HU were older (63.5 years vs. 52.3 years, p<0.001) and had a greater concentration of both high risk (24.9% vs. 11.4%, p=0.001) and intermediate risk (53.9% vs 38.4%, p<0.001) patients. They also had a higher rate of prior thrombosis (29.8% vs 11.3%, p<0.001) and leukopenia (10.1% vs. 3.0%, p<0.001). No differences were noted between gender, a history of prior hemorrhage, red blood cell transfusion requirements, or the presence of anemia/thrombocytopenia. In comparing symptom profiles, no significant differences were noted between TSS or individual symptoms with the exception of slightly more severe cough in HU patients (1.5 vs. 1.1, p=0.02, Figure 1). Anagrelide vs. Anagrelide Naive A total of 49 ET patients with active anagrelide use were compared to 794 ET patients with no history of anagrelide use. Patients using anagrelide had a longer mean disease duration (8.1 years vs. 5.8 years) and were more anemic (9.1% vs. 1.2%, p<0.001). No differences were noted between age, gender, risk scores, the presence of leukopenia/thrombocytopenia, a history of prior thrombosis or hemorrhage complications or red blood cell transfusion requirements. Additionally, there were no significant differences between TSS or individual symptom items (Figure 1). HU vs. Anagrelide A total of 402 patients currently using HU were compared to 39 patients currently using anagrelide. Overall, HU users were slightly older (63.5 years vs. 55.1 years, p<0.001) with a greater population of patients meeting high risk criteria (24.9% vs. 2.8%, p=0.002) and having a history of prior thrombosis (29.8% vs. 12.8%, p=0.02). Patients receiving anagrelide had a slightly longer disease duration (8.2 years vs. 6.0 years, p=0.0446). In comparing symptom profiles, no differences were noted in TSS or individual symptom items between cohorts. Discussion In this retrospective analysis, it does not appear cytoreduction with either HU and/or anagrelide has a significant impact on ET symptom burden despite reducing vascular events. Importantly, the higher risk scores in HU patients did not translate directly into greater patient symptomatology supporting previous studies demonstrating a poor association between these two items. Prospective trials measuring ET symptom change, in the setting of randomized trials will better quantify impact of cytoreduction on symptom burden as well as quantify impact of newer agents such as interferon or jak inhibition. Figure 1. Symptom Comparisons Between HU, Anagrelide and Other Therapy Figure 1. Symptom Comparisons Between HU, Anagrelide and Other Therapy Disclosures Kiladjian: Incyte Corporation: Consultancy; Novartis: Other: Travel grant; Research Funding paid to institution (Hôpital Saint-Louis et Université Paris Diderot); Novartis: Consultancy. Zweegman:Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Harrison:Sanofi: Honoraria, Speakers Bureau; Shire: Speakers Bureau; Gilead: Honoraria; CTI Biopharma: Consultancy, Honoraria, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau. Cervantes:Sanofi-Aventis: Consultancy; Novartis: Consultancy, Speakers Bureau; CTI-Baxter: Consultancy, Speakers Bureau. Barbui:Novartis: Speakers Bureau. Etienne:ARIAD: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Other: Congress Travel/Accomodations, Research Funding, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau. Roy:Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding. te Boekhorst:Novartis: Consultancy; CTI Biopharma: Consultancy. Vannucchi:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Shire: Speakers Bureau; Novartis: Other: Research Funding paid to institution (University of Florence), Research Funding; Baxalta: Membership on an entity's Board of Directors or advisory committees. Mesa:Novartis. Research- incyte, Gilead, cti, Genentech, promedior, NS Pharma: Consultancy.

Abstract Introduction Individuals with the Philadelphia chromosome negative myeloproliferative neoplasms (MPNs) have previously been shown to experience symptoms in excess to age and comorbidity matched peers. Although numerous assessments of symptom burden and quality of life have been utilized among MPN populations, including the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30), Patient Reported Outcomes Measurement Information System (PROMIS¨) fatigue scale, and Functional Assessment of Cancer Therapy-Lymphoma (FACT-Lym) and the Myeloproliferative Neoplasm Symptom Assessment Form Total Symptom Score (MPN-10), there are currently no validated assessments of overall health. Developed by the EuroQol Group to assess heath status, the EQ-5D is an internationally validated self-assessment which may be useful in the assessment of health state among MPN patients (Annals of Medicine, 2001. 33:337-43). Methods The EQ-5D evaluates five dimensions of mobility, self-care, usual activities, pain/discomfort and anxiety/depression, on a scale from no problems to extreme problems and assesses patient reported health state via a numerical visual analogue scale (VAS) ranging from 0 to 100. The health state score is a composite score of these items ranging from 0 to 1.0, with higher scores indicating an improved health state. EQ-5D survey participants were essential thrombocythemia (ET) and polycythemia (PV) patients participating in the MAJIC United Kingdom (UK) trial. The MAJIC trial is a randomized, phase II study of best available therapy versus JAK inhibition in individuals with PV or ET who have been resistant or intolerant of cytoreduction with hydroxyurea /hydroxycarbamide. This study was one of the first Trials Acceleration Programme (TAP) trials and is funded by Leukaemia Lymphoma Research, with drug supplied by Novartis. Only baseline EQ-5D assessments taken at study enrollment were included in this analysis. Comparative analysis was preformed using the MPN-10 (J Clin Oncol.2012. 30:4098-103). Results: Participant Demographics: Sixty six patients with ET and 55 patients with PV completed the EQ-5D questionnaire. Median respondent age was 65 years old and half of respondents were female (54%). Average MPN duration was 10 years for ET and 9.2 years for PV. EQ-5D Scoring: Severe to extreme difficulties in the items of mobility, self-care, usual activities, pain/discomfort and anxiety/depression were common (Table 1).Patients with PV tended to have higher proportion of patients with severe to extreme difficulties in individual disease dimensions, higher VAS score, and worsened health state compared to their essential thrombocythemia counterparts, although these effects were not significant. Average VAS health score was 70.4 (+21.2) for ET and 66.5 (+19.6). When evaluating the health state composite score, the mean ET score was 0.74 (+0.32) and mean PV score was 0.66 (+0.28). EQ-5D Validation: The EQ-5D had excellent internal consistency (CronbachÕs alpha=0.87) and strong internal correlation. When evaluating external validity, strong correlations existed between the EQ-5D and the MPN-SAF TSS scales for dimensions of mobility, usual activities, pain and overall health state (many items with r >0.5 and p<0.001). Conclusions: The EQ-5D is a valid and accurate instrument for the brief assessment of health state among MPN patients. This instrument demonstrates excellent clinical utility in a large clinical study cohort and can be used in both clinical practice and trial settings. When comparing EQ-5D health state scores, ET and PV patients had worsened health than the general UK population age 60 to 69 (0.774; Med Decis Making. 2011.31(6)800-4), but similar health to individuals with other malignancies including breast cancer (0.760), prostate cancer (0.743), and lung cancer (0.689). Disclosures Mesa: NS Pharma: Research Funding; Novartis Pharmaceuticals Corporation: Consultancy; Incyte Corporation: Research Funding; Pfizer: Research Funding; Promedior: Research Funding; CTI Biopharma: Research Funding; Gilead: Research Funding; Genentech: Research Funding; Pfizer: Research Funding. Harrison:CTI Biopharma: Consultancy, Honoraria, Speakers Bureau; Sanofi: Honoraria, Speakers Bureau; Shire: Speakers Bureau; Gilead: Honoraria; Novartis: Honoraria, Research Funding, Speakers Bureau.

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

AbstractMyeloproliferative Neoplasms (MPN) course can be complicated by thrombosis involving unusual sites as the splanchnic veins (SVT). Their management is challenging, given their composite vascular risk. We performed a retrospective, cohort study in the framework of the International Working Group for MPN Research and Treatment (IWG‐MRT), and AIRC‐Gruppo Italiano Malattie Mieloproliferative (AGIMM). A total of 518 MPN‐SVT cases were collected and compared with 1628 unselected, control MPN population, matched for disease subtype. Those with MPN‐SVT were younger (median 44 years) and enriched in females compared to controls; PV (37.1%) and ET (34.4%) were the most frequent diagnoses. JAK2V617F mutation was highly prevalent (90.2%), and 38.6% of cases had an additional hypercoagulable disorder. SVT recurrence rate was 1.6 per 100 patient‐years. Vitamin K‐antagonists (VKA) halved the incidence of recurrence (OR 0.48), unlike cytoreduction (OR 0.96), and were not associated with overall or gastrointestinal bleeding in multivariable analysis. Esophageal varices were the only independent predictor for major bleeding (OR 17.4). Among MPN‐SVT, risk of subsequent vascular events was skewed towards venous thromboses compared to controls. However, MPN‐SVT clinical course was overall benign: SVT were enriched in PMF with lower IPSS, resulting in significantly longer survival than controls; survival was not affected in PV and slightly reduced in ET. MPN‐U with SVT (n = 55) showed a particularly indolent phenotype, with no signs of disease evolution. In the to‐date largest, contemporary cohort of MPN‐SVT, VKA were confirmed effective in preventing recurrence, unlike cytoreduction, and safe; the major risk factor for bleeding was esophageal varices that therefore represent a major therapeutic target.

Abstract Background: The myeloproliferative neoplasms (MPNs), including essential thrombocythemia (ET), polycythemia vera (PV) and myelofibrosis (MF) can be characterized by heterogeneous symptoms, disease features, and prognosis. Timely monitoring of blood counts and if needed, referral for discussion of stem cell transplant (SCT), are critical to optimizing survival and quality of life. In connection with the MPN SCT Transplantation Timing Taskforce's (MS3T's) work in developing the DIPPS-based Stem Cell Spectrum Timing Tool, the survey was deployed to explore factors contributing to delayed entry to SCT. National Comprehensive Cancer Network (NCCN) guidelines for MPNs strongly recommend referral to specialized centers with expertise in the management of MPNs (Mesa et. al. 2017). To date, efforts to assess the timing and quality of MPN patient care from the patient's perspective have been minimal. Methods: Patients were recruited from MPN-related Facebook pages, subscribers of MPNforum Magazine and E-mail support groups including the MPN-NET, MPDchat, and the MPN Research Foundation. Hematologists, MPN patients, and advocates constructed the 11-item survey questions and content. The survey was available for patient response between July 4-11th2018. Patients were queried on MPN type, time of diagnosis, and details regarding knowledge of their MPN disease features and care. Data: Demographics.Overall 2382 MPN patients responded to the online survey. Of these, 901 (38%) patients had ET, 865 (36%) had PV, 561 (24%) had MF, 41 (2%) had MPN-unclassifiable or MPN/MDS overlap and 15 (1%) did not respond. Among MF patients, 56% reported having primary MF, 42% secondary MF, 1% prefibrotic MF, and 1% reported having already undergone SCT (1% did not specify type of MF or transplant). The majority of patients were diagnosed with their MPN by a hematology/oncology (77.8%) or family practice (15 %) physician. MPN Care provider and monitoring: Out of all respondents, 35% reported being cared for by an MPN specialist, 36% were not cared for by an MPN specialist and 27% were unsure if their provider was an MPN specialist. Overall less than half (42%) of patients reported having sought a second opinion from an MPN specialist. The majority (87%) of participants knew their mutational status relating to the highly publicized and widely tested JAK2 V617F mutation (73.8%) and CALR (10.2%). However, a statistically insignificant number of patients had any idea of other driving and secondary mutations including MPL, EZH2, SRSF2, IDH1/2 or ASLX-1. Blood counts were reviewed by a hematologist for the majority of patients (93% responded "yes", 4% responded "sometimes", 3% responded "no"). SCT Referral: Among ET and PV, <1% of patients reported being referred to SCT. For MF, 34% of participants reported having been referred for SCT discussion (30% for primary MF and 28% for secondary MF). Conclusions: MPN patients often report receiving care outside of the care of an MPN specialist. Additionally, despite the poor outcomes and higher likelihood of progression to AML, less than a third of patients with secondary MF report being referred for SCT discussion. Independent validation of patient responses, particularly in regards to MPN specialized care and timing of transplant discussion should be investigated further. However, these patient responses suggest many patients may be receiving less than optimal MPN care. These results demonstrate the importance of community hematology/oncology physician and patient education regarding optimal MPN care. Disclosures Mesa: UT Health San Antonio - Mays Cancer Center: Employment; Celgene: Research Funding; Novartis: Consultancy; Incyte Corporation: Research Funding; Pfizer: Research Funding; CTI Biopharma: Research Funding; Genentech: Research Funding; Promedior: Research Funding; NS Pharma: Research Funding; Gilead: Research Funding. Palmer:Novartis: Research Funding. Harrison:Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Gilead: Honoraria, Speakers Bureau; CTI BioPharma: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Speakers Bureau. Verstovsek:Italfarmaco: Membership on an entity's Board of Directors or advisory committees; Incyte: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Scherber:Gilead: Honoraria.

Abstract Background: Patients (pts) with polycythemia vera (PV) and essential thrombocythemia (ET) suffer from difficult MPN associated symptoms which impact quality of life (QoL). The impact of initial cytoreduction on ET/PV symptoms, resulting toxicity and QoL have not been prospectively studied. Methods: MPD-RC 112 trial (NCT01258856) randomized 168 therapy-naive (hydroxyurea [HU] <3 mo) high risk ET/PV pts (<5 years of disease) to response adjusted pegylated interferon alpha 2a (PEG) or HU. MPN symptoms, in depth toxicity assessment, and QoL were measured by two symptom instruments (MPN-SAF, EORTC QLQ-C30: baseline,3, 6, 9, and 12 mo) and toxicity questions. Blinded response review by European Leukemia Net (ELN) hematological responses (HR) was conducted at 12 months. Individual time point and longitudinal group comparisons were based on mixed models adjusting for age. Results: Patients: Of 168 randomized pts (86 HU, 82 PEG), 164 (98%) completed the survey package at baseline and 151 (HU 83%; PEG 98%) completed at least 1 survey during treatment. Median age was 61 (range 18-87) with 70 (42%) females; 81 (48%) / 87 (52%) with ET / PV; 46 (27%) had a history of a thrombosis. 119 (71%) received prior HU (up to 3 months). Baseline characteristics were balanced between arms with the exception of age (median HU 63 vs. PEG 60 yrs; p=0.02). Baseline Symptom Burden /QoL: Mean MPN-SAF Total Symptom Score (TSS), scale 0 [absent]-100 [worst imaginable] was 15.8 (SD 12.6; range 0-62.0) with means of 15.1 (SD 12.6) / 16.5 (SD 12.6) for ET / PV which were slightly lower than reported means of a previous cohort receiving any line of treatment (Scherber RM, JCO 2012). Median number of moderate (defined as score >=3) symptoms in ET patients was 3.0 and PV 4.0. Most common moderate symptoms were fatigue (65.9%), insomnia (37.2%), numbness (33.5%) , itching (29.9%), dizziness (27.4%), early satiety (26.8%) , headache (23.2%), sad mood (23.2%), inactivity (22%), concentration (20.7%). 50.6% of patients had one or more symptom with a score >=6. Mean QLQ-C30 global health status/QoL (GHS/QoL) was 70.8 (SD 21.9) - comparable to a general population (mean 71.2, SD 22.4) and better than a general cancer population (mean 61.3, SD 24.2; QLQ-C30 Reference Manual 2008). At baseline, TSS, symptoms, and QoL were similar between treatment arms. In patients with TSS >20 at baseline (highly symptomatic, n=50; ET:20, PV:30), median TSS was 28.0 (range 20.0 to 62.0); the highest scored symptom was fatigue (median=7.0), itching (median=4.5) and insomnia (median=4.0). Impact of Therapy on Symptom Burden/QoL: On HU, pts experienced worsening QoL (physical, cognitive functioning, HRQoL) and some persistent or transient worsened symptoms (inactivity, concentration (p<0.05) (Table 1)). On PEG, pts experienced worsening of fever, dyspnea, appetite loss and PEG-related symptoms including flu-like symptoms, injection site irritation, blurry vision, and visual changes (all p<0.05), but not sad mood (not corrected for antidepressants). In comparing arms, change in TSS significantly differed (p=0.01) between arms with increasing symptoms on HU vs PEG at 3 and 6 mo, but lower symptom burden at 9 and 12 mos (Figure 1). In highly symptomatic pts (with a baseline TSS > 20, n=50), improvements in weight loss, abdominal discomfort, fatigue, itching, fever, early satiety (12 m.) were observed in pts on HU. For PEG, in highly symptomatic pts, improvements were observed for overall TSS score, fatigue, inactivity, night sweats, and itching (with similar toxicities to all PEG patients). ELN Response and Symptom Burden/QoL: Among the 133 pts with 12-mo symptom data, complete hematologic response (CHR) rate was 43%. Inactivity and sad mood were worse in those patient achieving a CHR (inactivity: CHR worsening 0.68 vs PHR/NR better 0.26; p=0.03; sad mood: CHR worsening 0.67 vs PHR/NR better 0.67, p=0.002)). These latter changes were not related to higher doses utilized (in either arm), suggesting obtaining CHR may have negative effects on patient symptoms. Conclusions:In pts with a significant baseline MPN symptom burden, cytoreductive therapy has both a beneficial impact on baseline MPN symptom burden but also leads to therapy associated toxicity, although different patterns of efficacy and toxicity between HU and PEG. Achievement of a CHR in PV/ET may be associated with higher rates of drug related toxicities, and the value of achieving CHR may need further validation. Disclosures Mesa: Incyte Corporation: Research Funding; CTI Biopharma: Research Funding; Gilead: Research Funding; NS Pharma: Research Funding; Promedior: Research Funding; Novartis: Consultancy; Celgene: Research Funding; UT Health San Antonio - Mays Cancer Center: Employment; Genentech: Research Funding; Pfizer: Research Funding. Mascarenhas:Merck: Research Funding; CTI Biopharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Roche: Research Funding; Promedior: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Janssen: Research Funding. Rambaldi:Omeros: Consultancy; Roche: Consultancy; Celgene: Consultancy; Pfizer: Consultancy; Novartis: Consultancy; Italfarmaco: Consultancy; Amgen Inc.: Consultancy. Yacoub:Novartis: Honoraria, Speakers Bureau; Cara Therapeutics: Equity Ownership; Ardelyx, INC.: Equity Ownership; Inycte: Honoraria, Speakers Bureau; Seattle Genetics: Honoraria, Speakers Bureau; Dynavax: Equity Ownership. Harrison:Gilead: Honoraria, Speakers Bureau; CTI BioPharma: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau. Kiladjian:AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Mead:Elstar: Research Funding; Celgene: Research Funding; ARIAD: Consultancy; Cell Therapeutics: Consultancy; Evotek: Research Funding; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Consultancy. Kessler:Sangamo: Research Funding; Octapharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Honoraria, Research Funding; Dimension Advisory boards: Membership on an entity's Board of Directors or advisory committees; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; DSMB: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding; Biomarin: Research Funding. Kremyanskaya:Incyte: Research Funding. Rampal:Incyte: Honoraria, Research Funding; Constellation: Research Funding; Jazz: Consultancy, Honoraria; Stemline: Research Funding; Celgene: Honoraria. Hoffman:Incyte: Research Funding; Janssen: Research Funding; Merus: Research Funding; Formation Biologics: Research Funding; Summer Road: Research Funding. Dueck:Pfizer: Honoraria; Bayer: Employment; Phytogine: Employment.

Abstract Introduction HU is the treatment of choice for patients (pts) with high risk ET/PV, however, PEG has been proposed as an alternative option due to its proposed potential to modify disease course. An interim analysis of MPN-RC 112 (Blood 2016 128:479;) did not reveal a difference in PR/CR rates between HU and PEG therapy after 12 months in the first evaluable 75 pts treated. Here we present the results and long-term follow-up of all pts participating in this pivotal study [NCT01259856]. Methods MPN-RC 112 was a randomized, open label, phase 3 clinical trial comparing HU and PEG in pts with high risk ET/PV. Pts were treated for up to 12 months to achieve PR or CR (ELN/IWG-MRT response criteria). Pts who achieved a PR/CR continued therapy for up to a maximum of 6 years. Minimum follow up was 1 year from the time the last pt was randomized. The primary objective was to compare the CR rate following HU vs. PEG at 12 months with 3 month confirmation. Secondary objectives included a comparison of toxicity and tolerability; PR rates; incidence of specific pre-defined toxicities and tolerance to therapy; impact of therapy on key biomarkers; survival and incidence of myelodysplastic syndrome, myelofibrosis, or leukemic transformation; and incidence of major cardiovascular events. Bone marrow pathologic responses were evaluated by central blinded expert review at baseline, 12, 24 months and end of study. Results The study accrued 168 pts; 86 were randomized to HU and 82 to PEG. A summary of pt baseline characteristics by treatment arm is shown in Table 1 and were well balanced between the treatment arms except for median age which was higher in the HU arm (p=0.02). Median duration of follow up was 89.9 weeks (range, 0 to 292.3) and the median treatment duration was 86.0 weeks (range, 0 to 287.3). At 12 months, the overall response rate (ORR= PR+CR) was 69.8% and 78% for HU and PEG, respectively (p=0.22). Figure 1 shows the distribution of responses stratified by disease type. At 24 months, 59 pts were on treatment with an ORR of 22/25 (88%) for HU and 31/34 (91%) for PEG. When considering all 106 pts who were eligible to receive treatment for 24 months (due to study closure), the ORR was 22/54 (40.7%, PR: 11 (20.4%), CR: 11 (20.4%)) for HU and 31/52 (59.6%, (PR: 15 (28.9%), CR: 16 (30.8%)) for PEG, p=0.04. Best ORR at any time on study was seen in 70.9% and 81.7% of HU and PEG treated pts, respectively, p=0.10. The median maximum change from baseline spleen volume was -6% (-100.0 - +53.8) in 112 evaluable pts and was similar between arms, p=0.99. Bone marrow morphologic responses are shown in Table 2 and the best response (CR) seen at any time on study for ET treated with HU was 52% (12/23) vs PEG 32% (8/25) and for PV treated with HU 19% (6/31) vs PEG 6% (2/34). Cytogenetic analyses at diagnosis were available in 86% (144/168). An abnormal karyotype was seen in 15% (22/144). Five PV and one ET pt lost their chromosomal abnormalities: 3 after one year (HU=1, PEG=2) and three after two years of therapy (HU=2, PEG=1). AE information is available for 162 pts (HU: 80; PEG: 82) (Table 3). Six pts randomized to HU never received treatment due to study withdrawal prior to initiation of treatment. Sixty pts had a grade 3 or higher event [HU: 22 (27.5%) and PEG: 38 (46.3%)]. 28 PV pts had a grade 3/4 [HU: 10 (24.4%) and PEG: 18 (41.9%)]. Four pts had a grade 4/5 event [HU: 3 (7.3%) and PEG: 1 (2.3%)]. 32 ET pts had a grade 3/4 [HU:12 (30.8%) and PEG:20 (51.3%)]. Two pts had a grade 4/5 event [HU:1 (2.6%), PEG:1 (2.6%)]. Additional outcomes of interest on study include one death attributed to new diagnosis of lung cancer (HU:1), progression to myelofibrosis (HU:1), vertebral artery occlusion (HU:1), and cerebral vascular accident (PEG:1). Reasons for study discontinuation are shown in Table 4. The effect of therapy on symptom burden and quality of life will be presented in a companion abstract (Mesa et al). The impact of mutation status on therapeutic outcome as well as the molecular responses will be presented at the meeting. Conclusion The final analysis of MPN-RC 112 revealed that the CR rates in pts with high risk ET/PV treated with PEG and HU at 12 and 24 months were similar. PEG was associated with a higher rate of grade 3/4 toxicity. Each drug appeared equally capable of modifying the natural history of high risk ET/PV based upon their effects on spleen size, karyotypic abnormalities, histopathological parameters and the low incidence of thrombotic complications and disease evolution in both arms. Disclosures Mascarenhas: Novartis: Research Funding; Promedior: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Janssen: Research Funding; Merck: Research Funding; CTI Biopharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding. Rambaldi:Amgen Inc.: Consultancy; Pfizer: Consultancy; Novartis: Consultancy; Italfarmaco: Consultancy; Omeros: Consultancy; Roche: Consultancy; Celgene: Consultancy. Harrison:Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; CTI BioPharma: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Gilead: Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria, Speakers Bureau. Kiladjian:AOP Orphan: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Mead:Bristol-Myers Squibb: Consultancy; Elstar: Research Funding; Celgene: Research Funding; ARIAD: Consultancy; Evotek: Research Funding; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau; Cell Therapeutics: Consultancy. Kessler:Genentech: Research Funding; Sangamo: Research Funding; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Biomarin: Research Funding; Octapharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; DSMB: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Honoraria, Research Funding; Dimension Advisory boards: Membership on an entity's Board of Directors or advisory committees. Kremyanskaya:Incyte: Research Funding. Rampal:Stemline: Research Funding; Incyte: Honoraria, Research Funding; Constellation: Research Funding; Jazz: Consultancy, Honoraria; Celgene: Honoraria. Mesa:CTI Biopharma: Research Funding; Novartis: Consultancy; Genentech: Research Funding; Promedior: Research Funding; UT Health San Antonio - Mays Cancer Center: Employment; Pfizer: Research Funding; Celgene: Research Funding; Incyte Corporation: Research Funding; Gilead: Research Funding; NS Pharma: Research Funding. Dueck:Pfizer: Honoraria; Bayer: Employment; Phytogine: Employment. Hoffman:Incyte: Research Funding; Formation Biologics: Research Funding; Merus: Research Funding; Janssen: Research Funding; Summer Road: Research Funding.

Abstract Abstract 2818 Background: Pegylated interferon alpha-2a (Peg INF2a) has been demonstrated to be active therapy for high-risk essential thrombocythemia (ET) and polycythemia vera (PV), as well as treatment for early myelofibrosis (MF). We retrospectively analyzed the outcomes of Peg INF2a therapy in MPN patients treated outside the constraints of a clinical trial in the USA and EU. Methods: Clinical records of MPN patients treated at the participating centers, receiving Peg INF2a outside of the context of a clinical trial, were analyzed for response (ET and PV by ELN criteria; MF by EUNMET and IWG-MRT criteria), toxicity, and duration of response. Results: Patients: 115 patients were identified (54 PV (47%), 44 ET (38%), 17 MF (15%)) with a median age at diagnosis (48) and gender distribution (59% females) typical for the disorders. The patients had been diagnosed with the MPN a median of 44 months (0.0–312 months) prior to initiation of the Peg IFN2a and 64% harbored the JAK2-V617F mutation. The majority of patients (81%) had received at least one prior cytoreductive therapy for their disease (73 hydroxyurea, 39 anagrelide, 37 aspirin, 21 prior interferon (non pegylated), 3 phlebotomy alone). Therapy: Median starting dose of Peg INF2a was 45 micrograms/week (range: 22.5–180) with peak starting doses ranging from 30 to 300 micrograms/week. A total of 84 patients (73%) remain on Peg IFN2a with median duration of treatment of 17 months (range: 1.0–92). Toxicity: Overall the Peg INF2a was well tolerated. Hematological toxicity was Gr 3 or lower. There were 6 cases with anemia (5%), 10 with thrombocytopenia (9%) and 8 had leukopenia (7%). Most common non-hematologic toxicities were Gr 1–3 fatigue in 27 (23%), Gr 1 LFT elevation in 6 (5%), Gr 2–3 skin/allergic reaction in 6 (5%), Gr 1–2 nausea in 5 (4%), and Gr 2 mood disorder in 5 (4%) patients. Twenty patients (17%) discontinued therapy secondary to toxicity. Response: ET-PV: By ELN criteria, 30 PV patients achieved CR (55%), 17 achieved PR (31%), 4 achieved NR (7%), and 3 patients (5%) were lost to follow up or were too early to evaluate for response. In ET, the responses were CR in 27 (61%), PR in 7 (16%), NR in 4 (9%), and 6 patients (14%) were lost to follow up or were too early to evaluate for response. MF: The responses by IWG criteria were 1 CR (6%), 2 PR (12%), 2 CI (12%) and 9 SD (53%). By EUNMET, there were 2 CR (12%), 4 major responses (24%), 4 moderate responses (24%), 1 minor response (6%), 2 no response (12%), and 3 patients (17%) were lost to follow up or were too early to evaluate for response. Conclusions: Peg INF2a used at doses consistent with published clinical trials is active and well-tolerated when administered in a clinical setting outside of the support of a clinical trial. Given the majority of patients had previously failed cytoreductive therapy these results substantiate prior reports of efficacy of Peg INF2a in MPNs. Upcoming randomized clinical trials through the Myeloproliferative Disorders Research Consortium will help further define the role of Peg INF2a as first line therapy in high-risk MPNs. Disclosures: Mesa: Incyte: Research Funding; Lilly: Research Funding; SBio: Research Funding; Astra Zeneca: Research Funding; NS Pharma: Research Funding; Celgene: Research Funding.