A Phase I Study of XL019, a Selective JAK2 Inhibitor, in Patients with Primary Myelofibrosis, Post-Polycythemia Vera, or Post-Essential Thrombocythemia Myelofibrosis

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 98-98 ◽  
Author(s):  
Neil P. Shah ◽  
Patrycja Olszynski ◽  
Lubomir Sokol ◽  
Srdan Verstovsek ◽  
Ronald Hoffman ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Essential Thrombocythemia ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Reversible Inhibitor ◽  
Hematologic Toxicity ◽  
Low Grade ◽  
Costal Margin ◽  
Spleen Size ◽  
Activating Mutation

Abstract JAK2 V617F has been identified as a constitutive activating mutation in approximately half of patients with myelofibrosis (MF). MF, a myeloproliferative disorder comprised of primary myelofibrosis and the clinically indistinguishable entities of post-polycythemia vera or post essential thrombocythemia MF, has been reported to have a median survival of 4 years [Dupriez et al. (1996) Blood88:1013–18]. No effective therapies exist for patients with MF. XL019 is a potent, highly selective and reversible inhibitor of JAK2 which may have utility in treating MF, by ameliorating hepato-splenomegaly, constitutional symptoms, and progressive anemia. The objectives of this phase 1 study include safety evaluation, preliminary assessments of efficacy using International Working Group (IWG) response criteria for MF, and evaluation of pharmacokinetic and pharmacodynamic endpoints. Pharmacodynamic evaluations include quantitative PCR for peripheral blood JAK2 V617F allele burden and erythropoietin-independent colony formation. In addition, plasma and fixed blood samples are being collected to evaluate changes in protein biomarkers and JAK2 signaling pathways. To date, XL019 has been studied in 21 patients over multiple dose levels ranging from doses of 25 mg to 300 mg using different schedules of administration (3 weeks on, 1 week off; QD; and QMWF). Median age was 64 years (range, 47–87 years) and 16 patients (76%) carried the JAK2V617F mutation. Additionally, one patient had a MPLW515F mutation in the absence of a JAK2 mutation. No treatment-related hematologic adverse events (i.e. thrombocytopenia, anemia, neutropenia) have been observed to date. Reversible low-grade peripheral neuropathy (PNP) was observed in 7/9 patients treated at daily doses of ≥100 mg (Grade 1: 5 patients; Grade 2: 2 patients). XL019 doses below 100 mg using 2 different dosing schedules are currently being evaluated. To date, XL019 has resulted in reductions in splenomegaly and leukocytosis, stabilization of hemoglobin counts, improvements in blast counts, and resolution or improvement in generalized constitutional symptoms. The median spleen size in 15 patients measured below the costal margin by palpation was 14cm (range, 3–26cm). Three of 15 patients with palpable splenomegaly at baseline were JAK2 V617F mutation negative and did not experience spleen size reduction. Twelve of 12 (100%) evaluable patients with an activating mutation (JAK2 V617F: 11 patients; MPLW515F: 1 patient) experienced reduction in spleen size and 5 (42%) had a ≥50% decline from baseline. Ten of 11 patients with JAK2V617F activating mutations and baseline constitutional symptoms, reported improvements in generalized constitutional symptoms which include pruritus and fatigue. No significant non-hematologic or hematologic toxicity has been observed at the current dose level. On 25 mg dosing schedules, no signs of PNP have been observed with a follow-up period of up to 4 months. Overall, XL019 has demonstrated encouraging clinical activity and is generally well tolerated.

Sequential Analysis By Next Generation Sequencing of 18 Genes in Polycythemia Vera and Essential Thrombocythemia Reveals a Association Between Mutational Status and Clinical Outcome after 3-Year Follow-up

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2808-2808
Author(s):  
Damien Luque Paz ◽  
Aurelie Chauveau ◽  
Caroline Buors ◽  
Jean-Christophe Ianotto ◽  
Francoise Boyer ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Essential Thrombocythemia ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Jak2 V617f Mutation ◽  
Poor Prognostic Factor ◽  
Disease Evolution ◽  
Allele Burden ◽  
V617f Mutation

Abstract Introduction Myeloproliferative neoplasms (MPN) are molecularly characterized by driver mutations of JAK2, MPL or CALR. Other somatic mutations may occur in epigenetic modifiers or oncogenes. Some of them have been shown to confer a poor prognosis in primary myelofibrosis, but their impact is less known in Polycythemia Vera (PV) and Essential Thrombocythemia (ET). In this study, we investigated the mutational profile using NGS technology in 50 JAK2 V617F positive cases of MPN (27 PV and 23 ET) collected at the time of diagnosis and after a 3 year follow-up (3y). Patients and Methods All patients were JAK2 V617F positive and already included in the prospective cohort JAKSUIVI. All exons of JAK2, MPL, LNK, CBL, NRAS, NF1, TET2, ASXL1, IDH1 and 2, DNMT3A, SUZ12, EZH2, SF3B1, SRSF2, TP53, IKZF1 and SETBP1 were covered by an AmpliseqTM custom design and sequenced on a PGM instrument (Life Technologies). CALR exon 9 mutations were screened using fragment analysis. Hotspots that mutated recurrently in MPN with no sequencing NGS coverage were screened by Sanger sequencing and HRM. A somatic validation was performed for some mutations using DNA derived from the nails. The increase of a mutation between diagnosis and follow-up has been defined as a relative increase of twenty percent of the allele burden. An aggravation of the disease at 3y was defined by the presence of at least one of the following criteria: leukocytosis >12G/L or immature granulocytes >2% or erythroblasts >1%; anemia or thrombocytopenia not related to treatment toxicity; development or progressive splenomegaly; thrombocytosis on cytoreductive therapy; inadequate control of the patient's condition using the treatment (defined by at least one treatment change for reasons other than an adverse event). Results As expected, the JAK2 V617F mutation was found in all patients with the use of NGS. In addition, we found 27 other mutations in 10 genes out of the 18 genes studied by NGS (mean 0.54 mutations per patient). Overall, 29 of 50 patients had only the JAK2 V617F mutation and no other mutation in any of the genes analysed. No CALR mutation was detected. Nine mutations that were not previously described in myeloid malignancies were found. The genes involved in the epigenetic regulation were those most frequently mutated: TET2, ASXL1, IDH1, IDH2 and DNMT3A. In particular, TET2 mutations were the most frequent and occurred in 20% of cases. There was no difference in the number or in the presence of mutations between PV and ET. At 3y, 4 mutations appeared in 4 patients and 15 out of 50 patients (9 PV and 6 ET) were affected by an allele burden increase of at least one mutation. At 3y, 24/50 patients suffered an aggravation of the disease as defined by the primary outcome criterion (16 PV and 8 ET). The presence of a mutation (JAK2 V617Fomitted) at the time of the diagnosis was significantly associated with the aggravation of the disease (p=0.025). Retaining only mutations with an allele burden greater than 20%, the association with disease aggravation is more significant (p=0.011). Moreover, a mutation of ASXL1, IDH1/2 or SRSF2, which is a poor prognostic factor in primary myelofibrosis, was found in 8 patients, all having presented an aggravation of their disease (p=0.001). Only 4 patients had more than one somatic mutation other than JAK2 V617F and all of them also had an aggravation at 3y (p=0.046). In this cohort, appearance of a mutation at 3y was not associated with the course of the disease. Conversely, the increase of allele burden of at least one mutation was associated with an aggravation (p=0.019). Discussion and conclusion Despite the short follow-up and the limited number of patients, this study suggests that the presence of additional mutations at the time of the diagnosis in PV and TE is correlated to a poorer disease evolution. The increase of mutation allele burden, which reflects clonal evolution, also seems to be associated with the course of the disease. These results argue for a clinical interest in large mutation screening by NGS at the time of the diagnosis and during follow-up in ET and PV. Disclosures Ugo: Novartis: Membership on an entity's Board of Directors or advisory committees, Other: ASH travel.

Thrombocytosis

Hematology ◽  
2009 ◽  
Vol 2009 (1) ◽  
pp. 159-167 ◽  
Author(s):  
Radek C. Skoda
Keyword(s):  
Polycythemia Vera ◽  
Mouse Models ◽  
Essential Thrombocythemia ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Heterozygous State ◽  
Platelet Production ◽  
Thrombopoietin Receptor ◽  
Major Progress ◽  
Stimulation Of

Abstract Major progress in understanding the pathogenesis in patients with thrombocytosis has been made by identifying mutations in the key regulators of thrombopoietin: the thrombopoietin receptor MPL and JAK2. Together, these mutations can be found in 50% to 60% of patients with essential thrombocythemia or primary myelofibrosis and in 10% to 20% of hereditary thrombocytosis. A decrease in expression of the Mpl protein can cause thrombocytosis even in the absence of mutations in the coding sequence, due to a shift in the balance between stimulation of signaling in megakaryopoiesis and removal of thrombopoietin by receptor mediated internalization in platelets. When present in a heterozygous state the JAK2-V617F mutation preferentially stimulates megakaryopoiesis and in most cases manifests as essential thrombocythemia (ET), whereas homozygous JAK2-V617F reduces megakaryopoiesis in favor of increased erythropoiesis, resulting in polycythemia vera and/or myelofibrosis. In 30% to 40% of patients with ET or primary myelofibrosis (PMF) and in 80% to 90% of pedigrees with hereditary thrombocytosis the disease-causing gene remains unknown. Ongoing genetic and genomic screens have identified genes that, when mutated, can cause thrombocytosis in mouse models. A more complete picture of the pathways that regulate megakaryopoisis and platelet production will be important for finding new ways of controlling platelet production in patients with thrombocytosis.

scholarly journals Apoptosis induced by JAK2 inhibition is mediated by Bim and enhanced by the BH3 mimetic ABT-737 in JAK2 mutant human erythroid cells

Blood ◽  
2010 ◽  
Vol 115 (14) ◽  
pp. 2901-2909 ◽  
Author(s):  
Britta Will ◽  
Tanya Siddiqi ◽  
Meritxell Alberich Jordà ◽  
Takeshi Shimamura ◽  
Katarina Luptakova ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Apoptotic Pathway ◽  
Cd34 Cells ◽  
Activating Mutation ◽  
Induced Apoptosis ◽  
Jak2 Inhibition ◽  
Hematopoietic Cell Lines ◽  
Bh3 Mimetic

AbstractThe activating mutation JAK2 V617F plays a central role in the pathogenesis of polycythemia vera, essential thrombocythemia, and primary myelofibrosis. Inhibition of JAK2 activity leads to growth inhibition and apoptosis in cells with mutated JAK2. However, the proapoptotic proteins involved in JAK2 inhibition-induced apoptosis remain unclear. In this study, we show that JAK2 inhibition-induced apoptosis correlated with up-regulation of the nonphosphorylated form of the BH3-only protein Bim in hematopoietic cell lines bearing JAK2 mutations. Knockdown of Bim dramatically inhibited apoptosis induced by JAK2 inhibition, which was reversed by the BH3 mimetic agent ABT-737. In addition, ABT-737 enhanced the apoptosis induced by JAK2 inhibition in JAK2 V617F+ HEL and SET-2 cells. The combination of JAK inhibitor I and ABT-737 reduced the number of erythroid colonies derived from CD34+ cells isolated from JAK2 V617F+ polycythemia vera patients more efficiently than either drug alone. These data suggest that Bim is a key effector molecule in JAK2 inhibition-induced apoptosis and that targeting this apoptotic pathway could be a novel therapeutic strategy for patients with activating JAK2 mutations.

Phase II Study of CEP701, an Orally Available JAK2 Inhibitor, in Patients with Primary Myelofibrosis and Post Polycythemia Vera/Essential Thrombocythemia Myelofibrosis.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3543-3543 ◽  
Author(s):  
Srdan Verstovsek ◽  
Ayalew Tefferi ◽  
Steven Kornblau ◽  
Deborah Thomas ◽  
Jorge Cortes ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Polycythemia Vera ◽  
Phase Ii ◽  
Essential Thrombocythemia ◽  
Phase Ii Study ◽  
Subcutaneous Administration ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Common Mutation ◽  
Tyrosine Kinase 2

Polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) are myeloproliferative disorders (MPDs) associated with activating mutations of Janus tyrosine kinase 2 (JAK2) gene. The most common mutation, JAK2 V617F, has been reported in ∼97% of patients with PV, ∼50% with ET, and ∼50% with PMF. The resultant JAK2 protein is continuously autophosporylated and therefore always active. It is believed that this mutated tyrosine kinase contributes to the existence and progression of MPDs. CEP701 is an orally available potent low nanomolar inhibitor of wild type and mutated JAK2 tyrosine kinase in enzymatic and cellular assays. Significant inhibition (growth stasis) was observed following CEP-701 subcutaneous administration to V617F-mutated JAK2-dependent HEL.92 xenografts grown in immunocompromised mice. These results indicate that CEP-701 is an attractive candidate for clinical evaluation in patients with MPD carrying a mutated, constitutively activated JAK2. CEP701 is also a potent inhibitor of FLT3 and is being evaluated as FLT3 inhibitor in Phase II/III studies in patients with acute myeloid leukemia, at the starting dose of 80mg PO BID. We designed a Phase II study of CEP701, at the dose of 80 mg PO BID, in patients with PMF and post PV/ET MF, who harbor JAK2 V617F mutation. Eleven patients have been treated so far, seven males, median age 56 years (range, 38–69), median 3 prior therapies (range 0–6); 7 with abnormal cytogenetics; 8 with enlarged spleen (2 had splenectomy); 4 with enlarged liver; 5 transfusion dependent. Five patients have been followed for at least 1 month and have had stable disease. Response will be evaluated using International Working Group for MF Consensus Response Criteria. JAK2 V617F allele burden is being measured monthly. Except for Grade 2 nausea in one patient, no toxicities have been noted so far. Updated results will be presented at the meeting.

An Individual Patient Supply Program for Ruxolitinib for the Treatment of Patients with Primary Myelofibrosis (PMF), Post-Polycythemia Vera Myelofibrosis (PPV-MF), or Post-Essential Thrombocythemia Myelofibrosis (PET-MF).

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2844-2844
Author(s):  
Giovanni Barosi ◽  
Mohan Agarwal ◽  
Sonja Zweegman ◽  
Wolfgang Willenbacher ◽  
Sima Pakstyte ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Board Of Directors ◽  
Essential Thrombocythemia ◽  
Research Funding ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Jak2 V617f Mutation ◽  
Phase 3 ◽  
Advisory Committees ◽  
The Us

Abstract Abstract 2844 Background: Myeloproliferative neoplasms, including PMF, PET-MF, and PPV-MF, are a group of clonal stem cell–derived diseases characterized by bone marrow fibrosis, splenomegaly, and debilitating constitutional symptoms. Ruxolitinib (rux), a potent oral JAK1 & 2 inhibitor, demonstrated rapid and durable reductions in splenomegaly and improved MF-related symptoms and quality of life in 2 phase 3 studies (COMFORT-I and -II). Due to unmet medical need, rux has been made available through an individual patient supply program (IPSP) outside the US. Methods: Patients (pts) with PMF, PPV-MF, or PET-MF requiring treatment (as determined by their physician) and classified as high-, intermediate (int)-2–, or int-1–risk with an enlarged spleen were evaluated for eligibility on an individual basis by the sponsor, irrespective of JAK2 mutation status. The starting dose of rux was determined on the basis of baseline platelet count (15 or 20 mg twice daily for pts with platelet counts of 100–200 × 109/L and > 200 × 109/L, respectively) and can be adjusted for efficacy and safety. Dose changes during treatment, adverse events (AEs), and serious AEs (SAEs) are registered throughout the program. Results: To date, 1339 requests have been received from > 800 physicians in 48 countries, including locations in Europe, Latin America, the Middle East, and Asia. The baseline characteristics are shown in the Table for pts whose requests for access were approved (n = 1240). Drug resupply requests are received every ≈ 3 months. Follow-up information, based on the first resupply request, was available for 381/639 (60%) of the pts who were enrolled in the program prior to February 2012; 303 (80%) remain on rux therapy, 37 (10%) have discontinued, 11 (3%) died, and 30 (8%) did not initiate therapy. Spleen response was available for 247 pts (decreased, n = 201; unchanged, n = 39; increased, n = 7). Changes in constitutional symptoms were available for 203 pts (decreased, n = 151; unchanged, n = 49; increased, n = 3). In pts enrolled in the IPSP undergoing rux treatment, most pts who had a decrease in spleen length also had a decrease in symptoms. Dose-modification information was available for 259 pts, of whom 44 had dose increases and 89 had dose decreases. Reasons for dose modifications included efficacy (n = 28), safety (n = 69), and other reasons (n = 36). Safety information was available for 266 pts; 75 reported significant AEs or SAEs as determined by investigators. Enrolled pt characteristics are generally similar to those expected in the overall MF pt population. Thus far, the proportion of pts enrolled in the IPSP with the JAK2 V617F mutation (73%) is higher than that for the general MF population (50%-60%). This may reflect a misconception that JAK inhibition is primarily effective in pts who have the JAK2 V617F mutation, when in fact rux has demonstrated similar efficacy in both pt types in the phase 1/2 251 study and the two phase 3 COMFORT trials. This may also be reflected in the higher proportion of PPV-MF pts in the IPSP than in the general MF population (28% vs 10%-15%), of whom 95% are JAK2 V617 F–positive. Conclusions: Considerable requests for access to rux have been received through the IPSP, highlighting the need for an effective treatment in pts with a range of IPSS risk-assessment scores. The demographics of the IPSP pts are similar to those expected in the overall MF population. Responses and safety patterns observed in the IPSP appear to be comparable to those from the COMFORT trials. Disclosures: Off Label Use: Jakafi™ (ruxolitinib) is indicated in the United States for the treatment of patients with intermediate or high-risk myelofibrosis, including primary myelofibrosis, post–polycythemia vera myelofibrosis and post–essential thrombocythemia myelofibrosis. In Canada, JAKAVI ® is indicated for the treatment of splenomegaly and/or its associated symptoms in adult patients with primary myelofibrosis (also known as chronic idiopathic myelofibrosis), post-polycythemia vera myelofibrosis or post-essential thrombocythemia myelofibrosis. This abstract reports on a clinical study conducted outside the US including patients of all risk categories. All patients have provided written informed consent. Zweegman:Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding. Willenbacher:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Raymakers:Novartis: Consultancy. Cantoni:CSL Behring Switzerland: Research Funding; Robapharm/Pierre Fabre Oncology Switzerland: Research Funding; Janssen-Cilag Switzerland: Consultancy; Novartis Oncology Switzerland: Consultancy, Research Funding. Modi:Novartis Pharmaceuticals Corporation: Employment. Khan:Novartis: Employment. Perez:Novartis Pharmaceuticals Corporation: Employment, Equity Ownership. Gisslinger:AOP Orphan Pharmaceuticals AG: Consultancy, Speakers Bureau; Celgene: Consultancy, Research Funding, Speakers Bureau; Novartis: Consultancy, Research Funding, Speakers Bureau. Lavie:Novartis: Membership on an entity's Board of Directors or advisory committees. Harrison:Sanofi Aventis: Honoraria; YM Bioscience: Consultancy, Honoraria; Novartis: Honoraria, Research Funding, Speakers Bureau; Shire: Honoraria, Research Funding.

scholarly journals MOLECULAR GENETIC ABNORMALITIES IN THE GENOME OF PATIENTS WITH Ph-NEGATIVE MYELOPROLIFERATIVE NEOPLASIA AFFECTED BY IONIZING RADIATION AS A RESULT OF THE CHORNOBYL NUCLEAR ACCIDENT

2020 ◽  
Vol 25 ◽  
pp. 362-373
Author(s):  
L. Poluben ◽  
◽  
L. Neumerzhytska ◽  
S. Klymenko ◽  
P. Fraenkel ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Polycythemia Vera ◽  
Essential Thrombocythemia ◽  
Myeloproliferative Neoplasms ◽  
Molecular Genetic ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Genomic Research ◽  
History Of

Objective. to determine the frequency of major somatic mutations in the JAK2, MPL and CALR genes in the genome of patients with Ph-negative myeloproliferative neoplasms that occur in individuals who have been exposed to ionizing radiation as a result of the Chornobyl accident. Materials and methods. Molecular genetic analysis of genomic DNA samples isolated from blood was performed in 90 patients with Ph-negative myeloproliferative neoplasia (MPN) with a history of radiation exposure and 191 patients with spontaneous MPN utilizing allele-specific polymerase chain reaction (PCR). Results. The presence of major mutations in the genes JAK2, CALR and MPL was revealed in patients with MPN with a history of radiation exposure with a frequency 58.9 % (53 of 90), 12.2 % (11 of 90), and 0 % respectively, and without exposure with frequency 75.4 % (144 of 191), 3.1 % (6 out of 191) and 1.6 % (3 out of 191) respectively. Mutations JAK2 V617F in patients with spontaneous MPN were observed in each clinical form: polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). CALR mutations were detected exclusively in patients with PMF and ET, significantly more often in groups with a radiation exposure history (18.9 % and 33.3 %, vs. 4.2 % and 6.5 %) than without one. At the same time, the occurence of MPL mutations was determined only in patients with spontaneous MPN in 1.6 % of casees. Triple negative mutation status of genes JAK2, MPL and CALR prevailed in the group of patients with MPN with a history of radiation exposure and was 27.8 %, against 16.2 % in patients without radiation exposure (p = 0.05). Conclusions. Genomic research of patients with Ph-negative MPN revealed features of molecular genetic damage in those patients who were exposed to IR as a result of the Chornobyl accident and those with spontaneous MPN. The data obtained by determining of JAK2, MPL and CALR genes mutational status in the genome of patients with MPN is necessary to expand the understanding of the mechanism of leukogenesis, especially caused by radiation. Key words: myeloproliferative neoplasia, polycythemia vera, essential thrombocythemia, primary myelofibrosis, JAK2 V617F, MPL and CALR, ionizing radiation.

Sign in / Sign up

Export Citation Format

Share Document