The Effect of Eltrombopag on Platelet Resistance to Apoptosis: The Role of the Bcl-Xl Pathway

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1158-1158
Author(s):  
W. Beau Mitchell ◽  
Michele N Edison ◽  
Mariana P Pinheiro ◽  
Nayla Boulad ◽  
Bethan Psaila ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
De Novo ◽  
Apoptosis Resistance ◽  
Advisory Committees ◽  
Apoptotic Pathway ◽  
Akt Activation ◽  
Platelet Counts ◽  
Equity Ownership

Abstract Abstract 1158 INTRODUCTION: Immune thrombocytopenia (ITP) is typically characterized by increased platelet destruction and reduced platelet production. Eltrombopag and Romiplostim are thrombopoietin receptor (TPO-R) agonists that are known to increase platelet counts in patients with ITP by stimulating thrombopoiesis. Platelets also express TPO-R on their surface, but it is unknown whether the thrombopoietin mimetics (TPO-M) have a direct effect on the circulating platelets. Although controversial, in a very small number of ITP patients, TPO-M agents may increase platelet counts in 2–5 days, earlier than would be expected from de novo megakaryocytopoiesis. Platelet survival is hypothesized to be mediated by two molecular intermediates in an apoptotic pathway, Bcl-xL and Bak. Bcl-xL/Bak protein expression in megakaryocytes is regulated in part by TPO-mediated activation of Akt pathways through Jak2 and Stat5. We hypothesized that an increase in platelet count in the first week of treatment might be mediated by TPO-R signaling, resulting in decreased platelet apoptosis. This study explored whether Eltrombopag or Romiplostim treatment has anti-apoptotic effects on platelets of patients with ITP. METHODS: Following a treatment wash out period, 75 mg of Eltrombopag once daily or 10 mcg/kg weekly of Romiplostim was initiated for 2 weeks. Blood counts were measured on days 1, 3, 5, 8, 10, 12, and 15. Platelet function and survival was assessed on days 1, 8, and 15 by: immature platelet fraction (IPF), glycocalicin index, Bcl-xL inhibitor (ABT-737) assay, measurement of Bcl-xL by western blot, measurement of several members of the Bcl-xL Akt mediated, apoptotic pathway by flow cytometry (FACS), bleeding score, measurement of thrombin-anti-thrombin complexes (TATs), and quantification of microparticles. RESULTS: Eight of 10 patients responded to treatment with Eltrombopag with a platelet count ≥ 50,000/μL, and 6 of the 8 responders at least doubled their counts during the 2 weeks of treatment. All 3 patients treated with Romiplostim responded with platelet count ≥ 50,000/μL. In both treatment groups there was a significant increase in median platelet count (p<0.001), median large platelet count (p<0.01), and median absolute IPF (A-IPF, p<0.01), while there was no significant change in median % IPF. The dose of ABT-737 required to kill half of the platelets in the sample (IC50) in the Eltrombopag group was lower in patients at day 1 than in non-ITP controls, and there was an increase in resistance to apoptosis between days 1 and 8, but these changes did not reach statistical significance. Between days 8 and 15 the IC50 declined to pre-treatment levels. In the Romiplostim group there was no significant difference in IC50 between the control and the patients over the 2 weeks of study. There was no significant correlation between the platelet counts and the IC50 values. FACS analysis of members of the AKT signal transduction pathway revealed increased activation of each of the markers between days 1 and 8, followed by a decrease between days 8 and 15. The levels of Bcl-xL and phosphor-AKT(308) decreased from day 1 to day 15. The other lab tests are pending. DISCUSSION: Because the A-IPF increased by less than the platelet increase and because the lifespan of the A-IPF is not known, it is unclear if the platelet count increase is solely a result of increased platelet production. Platelet lifespan may be enhanced by Eltrombopag treatment as there was a parallel albeit transient increase in AKT activation markers and platelet apoptosis resistance in the Eltrombopag group. Treatment with Romiplostim did not appear to affect apoptosis resistance although it did result in transient AKT activation. Our data suggest that platelets are more resistant to apoptosis when the levels of anti-apoptotic factors (eg. PTEN, Phospho-GSK3β) involved in the AKT/Bcl-xL pathway are greatest despite a concomitant increase in pro-apoptotic factors (eg. Bak, Bax). Since both the increased AKT activation and apoptotic resistance returned to baseline at day 15, megakaryocytes and platelets already present at the start of treatment may respond differently than those generated de novo in the presence of TPO mimetics. Disclosures: Bussel: Portola: Consultancy; Eisai: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; GlaxoSmithKline: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Cangene: Research Funding; Genzyme: Research Funding; Immunomedics: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shionogi: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sysmex: Research Funding.

Plerixafor (Mozobil ®)Plus G-CSF Is Effective in Mobilizing Hematopoietic Stem Cells in Patients with Concurrent Thrombocytopenia Undergoing Autologous Hematopoietic Stem Cell Transplantation.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3229-3229 ◽  
Author(s):  
Ivana N Micallef ◽  
Eric Jacobsen ◽  
Paul Shaughnessy ◽  
Sachin Marulkar ◽  
Purvi Mody ◽  
...  
Keyword(s):  
Stem Cell ◽  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Advisory Committees ◽  
Hematopoietic Stem ◽  
Platelet Counts ◽  
Cd34 Cells ◽  
Low Platelet Count ◽  
Equity Ownership

Abstract Abstract 3229 Poster Board III-166 Introduction Low platelet count prior to mobilization is a significant predictive factor for mobilization failure in patients with non-Hodgkin's lymphoma (NHL) or Hodgkin's disease (HD) undergoing autologous hematopoietic stem cell (HSC) transplantation (auto-HSCT; Hosing C, et al, Am J Hematol. 2009). The purpose of this study is to assess the efficacy of HSC mobilization with plerixafor plus G-CSF in patients with concomitant thrombocytopenia undergoing auto-HSCT. Methods Patients who had failed successful HSC collection with any mobilization regimen were remobilized with plerixafor plus G-CSF as part of a compassionate use program (CUP). Mobilization failure was defined as the inability to collect 2 ×106 CD34+ cells/kg or inability to achieve a peripheral blood count of ≥10 CD34+ cells/μl without having undergone apheresis. As part of the CUP, G-CSF (10μg/kg) was administered subcutaneously (SC) every morning for 4 days. Plerixafor (0.24 mg/kg SC) was administered in the evening on Day 4, approximately 11 hours prior to the initiation of apheresis the following day. On Day 5, G-CSF was administered and apheresis was initiated. Plerixafor, G-CSF and apheresis were repeated daily until patients collected the minimum of 2 × 106 CD34+ cells/kg for auto-HSCT. Patients in the CUP with available data on pre-mobilization platelet counts were included in this analysis. While patients with a platelet count <85 × 109/L were excluded from the CUP, some patients received waivers and were included in this analysis. Efficacy of remobilization with plerixafor + G-CSF was evaluated in patients with platelet counts ≤ 100 × 109/L or ≤ 150 × 109/L. Results Of the 833 patients in the plerixafor CUP database, pre-mobilization platelet counts were available for 219 patients (NHL=115, MM=66, HD=20 and other=18.). Of these, 92 patients (NHL=49, MM=25, HD=8 and other=10) had pre-mobilization platelet counts ≤ 150 × 109/L; the median platelet count was 115 × 109/L (range, 50-150). The median age was 60 years (range 20-76) and 60.4% of the patients were male. Fifty-nine patients (64.1%) collected ≥2 × 109 CD34+ cells/kg and 13 patients (14.1%) achieved ≥5 × 106 CD34+ cells/kg. The median CD34+ cell yield was 2.56 × 106 CD34+ cells/kg. The proportion of patients proceeding to transplant was 68.5%. The median time to neutrophil and platelet engraftment was 12 days and 22 days, respectively. Similar results were obtained when efficacy of plerixafor + G-CSF was evaluated in 29 patients with platelet counts ≤ 100 × 109/L (NHL=12, MM=10, HD=3 and other=4). The median platelet count in these patients was 83 × 109/L (range, 50-100). The median age was 59 years (range 23-73) and 60.4% of the patients were male. The minimal and optimal cell dose was achieved in 19(65.5%) and 3(10.3%) patients, respectively. The median CD34+ cell yield was 2.92 × 106 CD34+ cells/kg. The proportion of patients proceeding to transplant was 62.1%. The median time to neutrophil and platelet engraftment was 12 days and 23 days, respectively. Conclusions For patients mobilized with G-CSF alone or chemotherapy ±G-CSF, a low platelet count prior to mobilization is a significant predictor of mobilization failure. These data demonstrate that in patients with thrombocytopenia who have failed prior mobilization attempts, remobilization with plerixafor plus G-CSF allows ∼65% of the patients to collect the minimal cell dose to proceed to transplantation. Thus, in patients predicted or proven to be poor mobilizers, addition of plerixafor may increase stem cell yields. Future studies should investigate the efficacy of plerixafor + G-CSF in front line mobilization in patients with low platelet counts prior to mobilization. Disclosures Micallef: Genzyme Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding. Jacobsen:Genzyme Corporation: Research Funding. Shaughnessy:Genzyme Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Marulkar:Genzyme Corporation: Employment, Equity Ownership. Mody:Genzyme Corporation: Employment, Equity Ownership. van Rhee:Genzyme Corporation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Final Results from an International, Multi-Center, Single-Arm Study Evaluating the Safety and Efficacy of Romiplostim in Adults with Primary Immune Thrombocytopenia (ITP),

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3279-3279 ◽  
Author(s):  
Ann Janssens ◽  
Michael D. Tarantino ◽  
Robert Bird ◽  
Maria Gabriella Mazzucconi ◽  
Ralph Vincent V. Boccia ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Platelet Response ◽  
Employment Equity ◽  
Advisory Committees ◽  
Platelet Production ◽  
Platelet Counts ◽  
Equity Ownership

Abstract Abstract 3279 Background: ITP is an autoimmune disorder characterized by increased platelet destruction and suboptimal platelet production. Romiplostim stimulates platelet production via the TPO-receptor, and is recommended for second- and third-line treatment of chronic ITP in adults. We report final data from a large prospective study of romiplostim in adults with ITP of varying duration and severity. Methods: Eligibility criteria were broad: patients ≥18 years of age, who had received prior ITP therapies (final protocol amendment: ≥1, previous amendments: ≥3), with low platelet counts (final amendment: ≤ 30 × 109/L, previous amendments: ≤ 10, ≤ 20 × 109/L) or experiencing uncontrolled bleeding. The only excluded comorbidities were: hematological malignancy, myeloproliferative neoplasms, MDS and bone marrow stem cell disorder. Romiplostim was initiated at 1 (final amendment) or 3 (previous amendments) μg/kg/week, with dose adjustments allowed to maintain platelet counts ≥50 × 109/L. Patients could continue on study until they had access to commercially available romiplostim. Rescue medications were allowed at any time; concurrent ITP therapies could be reduced when platelet counts were > 50 × 109/L. Primary endpoint was incidence of adverse events (AEs) and antibody formation. Secondary endpoint was platelet response, defined as either (1) doubling of baseline count and ≥ 50 × 109/L or (2) ≥20 × 109/L increase from baseline. Results: A total of 407 patients received romiplostim, 60% of whom were female. Median (Q1, Q3) time since ITP diagnosis was 4.25 (1.20, 11.40) years (maximum 57.1 years), with 51% of patients splenectomised and 39% receiving baseline concurrent ITP therapies. Seventy-one percent of patients completed the study, with requirement for alternative therapy and withdrawn consent the most common reasons for discontinuation (5% each). Median (Q1, Q3) on-study treatment duration was 44.29 (20.43, 65.86) weeks (maximum 201 weeks), with a total of 20,201 subject-weeks on study. Incidence and type of AEs were consistent with previous studies. The most common serious treatment-related AEs were cerebrovascular accident, headache, bone marrow reticulin fibrosis (with no evidence of positive trichrome staining for collagen and no evidence suggesting primary idiopathic myelofibrosis), nausea, deep vein thrombosis, hemorrhage and pulmonary embolism, with each reported in 2 of 407 (0.5%) patients. All other serious treatment-related AEs were each reported in one patient. Eighteen patients died; 3 deaths (hemolysis, intestinal ischaema, aplastic anemia) were considered treatment-related. No neutralizing antibodies to romiplostim or TPO were reported. Approximately 90% of patients achieved each of the platelet response definitions, regardless of splenectomy status. Overall, median (Q1, Q3) time to response was 2 (1, 4) weeks for response definition 1, and 1 (1, 3) week for response definition 2. Median (Q1, Q3) baseline platelet count was 14 (8, 21) × 109/L. After 1 week of treatment median (Q1, Q3) platelet count had increased to 42 (18, 101) × 109/L. From week 8 onwards, and excluding counts within 8 weeks of rescue medication use, median platelet counts were consistently above 100 × 109/L (range 101.0–269.5 × 109/L). Median (Q1, Q3) average weekly romiplostim dose was 3.62 (1.99, 6.08) μg/kg. Summary/conclusions: This is the largest prospective study in adult ITP reported to date. The data reported here are similar to those reported for previous romiplostim studies, with romiplostim able to safely induce a rapid platelet response in adult ITP patients with low platelet counts or bleeding symptoms. Romiplostim is an important, well-tolerated, treatment option for adult ITP patients, which significantly increases and maintains platelet counts. Adverse Event Subject Incidence Platelet Response Disclosures: Janssens: Amgen: Consultancy; Roche: Speakers Bureau; GSK: Membership on an entity's Board of Directors or advisory committees. Tarantino:Cangene corporation: Research Funding; Baxter: Research Funding; Talecris: Honoraria, Speakers Bureau; Up-to-date: Patents & Royalties; The Bleeding and Clotting Disorders Institute: Board Member. Bird:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; GSK: Membership on an entity's Board of Directors or advisory committees. Boccia:Amgen: Equity Ownership, Honoraria, Speakers Bureau. Lopez-Fernandez:Amgen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Kozak:Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Steurer:Amgen: Honoraria. Dillingham:Amgen Limited: Employment, Equity Ownership. Lizambri:Amgen: Employment, Equity Ownership.

Thromboembolic Events Observed in Eltrombopag Clinical Trials in Chronic Immune Thrombocytopenic Purpura.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2423-2423 ◽  
Author(s):  
James B. Bussel ◽  
Gregory Cheng ◽  
Mansoor N. Saleh ◽  
Sandra Vasey ◽  
Manuel Aivado ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Thromboembolic Events ◽  
Study Medication ◽  
Normal Range ◽  
Advisory Committees ◽  
Thrombocytopenic Purpura ◽  
Platelet Counts ◽  
Equity Ownership

Abstract Abstract 2423 Poster Board II-400 BACKGROUND: Eltrombopag (PROMACTA®; GlaxoSmithKline, Collegeville, PA, USA), an oral, small molecule, thrombopoietin receptor agonist, was recently approved in the United States for the treatment of patients with chronic immune thrombocytopenic purpura (ITP). Limited published data indicate that patients with chronic ITP experience thromboembolic events (TEEs) with a frequency of 3% to 6%. (Aledort, Am J Hematol, 2004; Bennett, Haematologica, 2008). OBJECTIVE: To evaluate the incidence of TEEs in patients with chronic ITP treated with eltrombopag and to determine if the occurrence of TEEs was associated with elevated platelet counts. METHODS: Data from 446 patients from 3 placebo-controlled eltrombopag studies (TRA100773A, TRA100773B, and RAISE) and 2 open-label studies (REPEAT and EXTEND) were analyzed. The frequency of TEEs or suspected TEEs before and after the first dose of study medication (placebo or eltrombopag) was examined across the program. Potential risk factors, including platelet counts proximal to the event, were evaluated in patients experiencing a TEE. RESULTS: Prior to the initiation of study medication (placebo or eltrombopag), 16/493 (3.2%) of the patients entering the program had a history of TEEs (one of these patients experienced 2 additional TEEs [TIA, MI] while on treatment with eltrombopag). Across the ITP clinical program, 17/446 patients treated with eltrombopag (3.8%) experienced 22 TEEs. No patient treated with placebo experienced a TEE. The patient-years (PYs) of exposure to study medication was approximately 14 times greater for patients treated with eltrombopag compared to placebo (eltrombopag 377 PYs; placebo 26 PYs). Most patients (13/17) experienced 1 TEE; 3 patients experienced 2, and 1 patient experienced 3 (2 TEEs were 6 months off-therapy). The most common TEEs were deep vein thrombosis (n=8) and pulmonary embolism (n=6). A total of 18/22 events were resolved or resolving at the time of this analysis; all patients experiencing a TEE had at least 1 risk factor for these events other than ITP (eg, use of IVIg [n=3], hospitalization with no prophylactic anticoagulation [n=4], oral corticosteroids [n=6]). The platelet counts proximal to the event ranged from 14,000/μL to 420,000/μL. The majority of patients had platelet counts below 150,000/μL (9; 53%) or between 150,000/μL and 400,000/μL (5; 29%); 2 had platelet counts above 400,000/μL and the platelet count in 1 was unknown. All 446 patients were categorized by the maximum platelet count achieved during treatment with eltrombopag (above normal [>400,000/μL], normal range [150–400,000/μL], below normal range [<150,000/μ]; Table 1). The majority of patients (14; 82%) experienced the TEEs at a platelet count lower than their maximum platelet count, while 3 patients (18%) experienced a TEE proximal to their maximum platelet count. CONCLUSION: TEEs occurred with eltrombopag. None occurred with placebo; however, the PYs of exposure was considerably less with placebo than with eltrombopag. The frequency of TEEs observed during eltrombopag treatment (3.8%) is similar to that reported in the literature and prior to enrollment in the eltrombopag program (3.2%). No discernible correlation has been observed between platelet count increases and TEEs, and these events do not appear to be associated with maximum platelet counts during treatment with eltrombopag. Disclosures: Bussel: Sysmex: Research Funding; Eisai, Inc: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Immunomedics: Research Funding; Amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; GlaxoSmithKline: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Genzyme: Research Funding; Scienta: Speakers Bureau; Shionogi: Membership on an entity's Board of Directors or advisory committees. Cheng:GlaxoSmithKline: Research Funding. Saleh:GlaxoSmithKline: Speakers Bureau; Amgen: Speakers Bureau. Vasey:GlaxoSmithKline: Employment. Aivado:GlaxoSmithKline: Employment. Brainsky:GlaxoSmithKline: Employment.

scholarly journals Effects of Anti-Glycoprotein Antibodies on Response of Immune Thrombocytopenia Patients to Thrombopoietin Receptor Agonists and on Megakaryocytes Viability

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1048-1048
Author(s):  
Marina Izak Karaev ◽  
Alexandra Kruse ◽  
Margaret Morrisey ◽  
Heyu Ni ◽  
Zhu Guangheng ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Treatment Option ◽  
Research Funding ◽  
Immune Thrombocytopenia ◽  
Advisory Committees ◽  
Thrombopoietin Receptor Agonists ◽  
Platelet Counts ◽  
Thrombopoietin Receptor ◽  
Equity Ownership

Abstract Background Immune Thrombocytopenia (ITP) is a bleeding disorder due to a combination of increased platelet destruction and reduced production, often secondary to anti-platelet/megakaryocyte antibodies. The presence of antibodies to glycoproteins (GP) IIb/IIIa (integrin αIIbβ3) and GPIb/IX, detected in majority of ITP patients, may correspond to different responses to treatment, i.e., anti-GPIb is associated with more severe disease, and less responsive to intravenous immunoglobulins and steroids. Thrombopoietin Receptor Agonists (TPO-RA) increase platelet production by stimulation of megakaryopoesis. Predictors of response to TPO-RA and influence of antibody profile on response are currently unknown. In our previous study we investigated Absolute Immature Platelet Fraction (A-IPF) prior to TPO-RA treatment and did not find a correlation between A-IPF, anti-GP antibodies, and platelet counts. The aims of this study were to further investigate: 1. The role of anti-GP antibodies in response to TPO-RA; 2. Effect of patients' antibodies on megakaryocyte (MK) viability, maturation, apoptosis and formation of proplatelets (in vitro); 3. The influence of patients' clinical characteristics on response to TPO-RA. Materials and Methods 91 patients with persistent or chronic ITP, were treated at Weill Medical College of Cornell University until January 2015 with TPO-RAs: 52 patients received eltrombopag, 22 romiplostim and 17 avatrombopag. Serum samples of 84 patients were analyzed for the presence of anti-GP by MAIPA assay as previously described. Patients with baseline platelet counts less than <30x109/L were defined as responders to TPO-RA if the average of their six median monthly platelet counts was ≥50x109/L and doubled from average baseline counts (prior to TPO-RA). Patients with baseline platelet counts 30-50x109/L were responders if the average platelet count was ≥75x109/L. MKs were derived from human umbilical cord blood stem cells as previously described. Cells were grown using SFEM medium, adding on day 0 of culture 50 ng/ml recombinant TPO and aliquots of serum of ITP patients or healthy controls. The percentages of immature (CD41+/CD42-), mature (CD41+/CD42+), viable and apoptotic MKs were analyzed by flow cytometry on day 12. Apoptosis was analyzed by measuring Mitochondrial Outer Membane Potential (MOMP) and Phosphatidyl Serine (PS) externalization. MKs were considered apoptotic if they had positive staining for PS externalization, viable if positive for MOMP, and dead if positive for 7-Aminoactinomycin D (7AAD). Proplatelet formation by MKs was analyzed by microscopy. Statistical analysis using unpaired T-test and Pearson correlation test were performed. Results Ninety-one patients were included, 40 male (44%) and 51 female (56%), with a median age of 37.4 years (range 2-87). Median duration of ITP before TPO-RA treatment was 8 years (range 0.3-45). The 18/91 (19.8%) non-responders to TPO-RA were not different from the 73/91 responders in age, gender, number of prior treatments, duration of ITP, and past splenectomy. The presence of either or both anti-GP antibodies was correlated with average lower platelet counts on TPO-RA: 82.3 x109/L versus 123x109/L in patients without detected antibodies ("neither") (p=0.003). However, the response to TPO-RA was not influenced by the type of antibody: in patients with anti-GPIb the average platelet count was 76.1x109/L, and with anti-GPIIb/IIIa 80.7x109/L (Figure 1). In culture, excess dead MKs were found in anti-GPIb group and antiGPIb&antiGPIIb/IIIa group compared to "neither" group (p=0.0013 and p=0.027 respectively) and comparing antiGPIb&antiGPIIb/IIIa to control (p=0.0025). We did not observe changes in the degree of MK apoptisis or in MK maturation in the presence of serum antibodies. In cultures treated with serum of patients having anti-GPIb, less proplatelets were detected comparing to control (p=0.044) or to "neither" (p=0.0039). We conclude that patients with anti-GP antibodies respond less to TPO-RA, however there is no difference in response to TPO-RA between patients having anti-GPIb and anti-GPIIb/IIIa, unlike responses to other treatment modalities (e.g., steroids or immunoglobulins). TPO-RA could be a preferable treatment option in ITP patients having anti-GPIb. Figure 1. Average 6-months platelet counts of TPO-RA-treated ITP patients divided into groups by presence of antibody/ies. Figure 1. Average 6-months platelet counts of TPO-RA-treated ITP patients divided into groups by presence of antibody/ies. Disclosures Off Label Use: Eltrombopag, romiplostim and avatrombopag are a thrombopoietin receptor agonist approved for the treatment of thrombocytopenia in adults with chronic ITP. In some preliminary studies these medicines found as safe and effective treatment option in children and adolescents. Bussel:amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; GlaxoSmithKline: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; Novartis: Consultancy, Research Funding; Genzyme: Consultancy; BiologicTx: Research Funding; Ligand: Consultancy, Research Funding; Eisai: Consultancy, Research Funding; Shionogi: Consultancy, Research Funding; momenta: Consultancy; Protalex: Consultancy; Symphogen: Consultancy.

scholarly journals PETIT and PETIT 2: Treatment with Eltrombopag in 171 Children with Chronic Immune Thrombocytopenia (ITP)

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1450-1450 ◽  
Author(s):  
James B. Bussel ◽  
John D. Grainger ◽  
Purificacion Garcia de Miguel ◽  
Jenny M. Despotovic ◽  
Franco Locatelli ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Employment Equity ◽  
Advisory Committees ◽  
Platelet Counts ◽  
Chronic Itp ◽  
Thrombopoietin Receptor ◽  
Count Response ◽  
Equity Ownership

Abstract Background: Eltrombopag (EPAG), an oral thrombopoietin receptor agonist, is approved for treating thrombocytopenia in adults with chronic immune thrombocytopenia (ITP) with insufficient response to prior therapy. Pooled data from 2 similarly designed, randomized, double-blind, placebo (PBO)-controlled studies investigating safety and efficacy of EPAG in pediatric ITP are presented here. Methods: Subjects aged 1 to <18 years with a confirmed diagnosis of persistent or chronic ITP and a platelet count <30 Gi/L at day 1 were randomized 2:1 to EPAG or PBO and stratified by age: 12–17 years (Cohort 1), 6–11 years (Cohort 2), and 1–5 years (Cohort 3). Subjects could continue baseline ITP medications. After the PBO-controlled randomized phase, subjects were permitted to complete 17 or 24 weeks of treatment with open-label (OL) EPAG. Dose was adjusted based on platelet counts to a maximum of 75 mg daily. Results: A total of 174 subjects were enrolled in both studies; 171 received ≥1 dose of EPAG. 159 subjects were randomized (intent-to-treat population), and 157 received ≥1 dose of randomized study treatment (safety population). In the randomized period, 3 EPAG and 1 PBO subject discontinued study treatment, of which 2 EPAG and 1 PBO discontinued due to adverse events (AEs). In the OL-EPAG period, an additional 14 EPAG subjects discontinued study treatment, 6 due to AEs. Males comprised 47% of the EPAG and PBO groups and 20% and 24% were East Asians, respectively. Most subjects (93%) were diagnosed with ITP for ≥12 months, and 13% were receiving ITP medications at baseline. The majority of subjects (81%) received ≥2 prior ITP therapies. Most subjects (59%) had a baseline platelet count <15 Gi/L. All 9 (6%) splenectomized subjects were randomized to the EPAG group. Randomized Period A higher proportion of EPAG versus PBO subjects (62% vs 24%; P < 0.001) achieved a response with platelet counts ≥50 Gi/L at least once between weeks 1–6 (Cohort 1, 64% vs 11%; Cohort 2, 64% vs 27%; Cohort 3, 54% vs 36%, respectively). At each week, a higher proportion of EPAG subjects had a response versus PBO (Fig. 1). A lower proportion of EPAG subjects (13%) received rescue treatment compared with PBO subjects (31%; P = 0.009). The odds of having World Health Organization (WHO) bleeding grades 1–4 (0.19; P = 0.011) and clinically significant (WHO grades 2–4) bleeding (0.29; P = 0.007) were lower for EPAG versus PBO subjects. EPAG-Only Period Sustained reduction or discontinuation of baseline ITP medications, primarily corticosteroids, was achieved by 50% of subjects; 81% of subjects had a platelet count response at least once; 52% (n = 80/154) had a platelet count response for ≥50% of assessments; and 38% (n = 58/154) responded for ≥75% of assessments. For >13 of 24 weeks, 47% of subjects achieved responses (Fig. 2). The median average daily dose for EPAG-exposed patients in Cohorts 1, 2, and 3 were 64.0 mg (0.93 mg/kg), 57.6 mg (1.50 mg/kg), and 37.0 mg (2.02 mg/kg), respectively. AEs Similar proportions of subjects in the EPAG and PBO groups reported an AE during the randomization period. The most common AEs (≥10% of subjects) were headache, upper respiratory tract infection, and nasopharyngitis in the EPAG group, and headache, epistaxis, and vomiting in the PBO group. Serious AEs (SAEs) were reported in 8% of EPAG subjects versus 12% of PBO subjects. No SAEs were reported by >1 subject in either treatment group except epistaxis, which was reported by 2 subjects in the PBO group. No SAEs were common to both treatment groups. In the randomized period, an ALT elevation of ³3 x ULN occurred in 5 (4.7%) subjects in the EPAG group and no subjects in the PBO group. In the OL period, there were an additional 7 subjects with ALT ³3 x ULN. All elevations resolved either while still on treatment or after discontinuation of study treatment. Overall, the hepatobiliary laboratory findings were mostly mild, reversible, and not accompanied by impaired liver function. Fewer EPAG than PBO subjects reported bleeding AEs (17% vs 36%, respectively). No thromboembolic events were reported. Cataract events were experienced by 2 subjects who received EPAG; both had used corticosteroids and 1 had pre-existing cataracts. Conclusions: EPAG was safe and raised platelet counts in 62% of pediatric patients with persistent and chronic ITP during the randomized phase. Treatment with EPAG was well tolerated in both studies as evidenced by the low incidence of treatment discontinuations due to AEs. Disclosures Bussel: Shionogi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Rigel: Honoraria; Novartis: Honoraria; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Immunomedics: Research Funding; IgG of America: Research Funding; GlaxoSmithKline: Equity Ownership, Honoraria, Research Funding; Genzyme: Research Funding; Eisai, Inc.: Research Funding; Cangene: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria; Amgen: Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Symphogen: Membership on an entity's Board of Directors or advisory committees; Sysmex: Research Funding. Off Label Use: Eltrombopag is a thrombopoietin receptor agonist approved for the treatment of thrombocytopenia in adults with chronic ITP. Use in children and adolescents will be discussed.. Grainger:GlaxoSmithKline: Honoraria; Baxter: Honoraria, Research Funding; Amgen: Honoraria. Pongtanakul:GlaxoSmithKline: Research Funding. Komvilaisak:GlaxoSmithKline: I am an investigator on this study. Other. Sosothikul:CSL Behring: Research Funding; GlaxoSmithKline: Research Funding. Drelichman:GlaxoSmithKline: I am investigator on this study. Other. David:GlaxoSmithKline: Research Funding. Marcello:GlaxoSmithKline: Employment. Iyengar:GlaxoSmithKline: Employment. Chan:GlaxoSmithKline: Employment. Chagin:GlaxoSmithKline: Employment. Theodore:GlaxoSmithKline: Employment, Equity Ownership. Bakshi:GlaxoSmithKline: Employment, Equity Ownership. Bailey:GlaxoSmithKline: Employment, Equity Ownership.

A Randomized, Double-Blind, Placebo-Controlled Phase 1/2 Study to Determine the Safety and Efficacy of Romiplostim in Children with Chronic Immune (Idiopathic) Thrombocytopenic Purpura (ITP).

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 680-680 ◽  
Author(s):  
George R. Buchanan ◽  
Lisa Bomgaars ◽  
James B. Bussel ◽  
Diane J. Nugent ◽  
David J. Gnarra ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Treatment Period ◽  
Research Funding ◽  
Bleeding Events ◽  
Employment Equity ◽  
Advisory Committees ◽  
Platelet Counts ◽  
Chronic Itp ◽  
Equity Ownership

Abstract Abstract 680 Introduction: ITP is an autoimmune disorder characterized by thrombocytopenia due to accelerated destruction as well as suboptimal platelet production. Childhood ITP is most commonly an acute illness; however, chronic ITP (duration > 6 months) develops in 20%–30% of ITP cases. Romiplostim, a peptibody protein designed to increase platelet production, is approved for treating chronic ITP in adults. The objective of this study was to evaluate the safety and efficacy of romiplostim in the treatment of thrombocytopenia in children with chronic ITP. Patients and Methods: ITP patients aged 12 months to <18 years with persistent severe thrombocytopenia for at least six months before enrollment (mean of 2 platelet counts ≥ 30 × 109/L at baseline) were included in this study. Patients were randomized (3:1) to receive romiplostim or placebo and stratified by age: 12 months - <3 years (N=4), 3 - <12 years (N=8), and 12 - <18 years (N=8). Treatment for a 12 week period was followed by a 4 week pharmacokinetic (PK) assessment period for responding patients (those who achieved a platelet count of >20 × 109/L above baseline for 2 consecutive weeks without rescue therapy at any point during the treatment period). Treatment was initiated at 1 μg/kg once weekly by subcutaneous injection. The dose was adjusted in 2 μg/kg increments every two weeks, to a maximum dose of 10 μg/kg/week based on weekly platelet counts. The incidence of adverse events (AEs) during the 12-week treatment period and the number of patients achieving platelet counts >50 × 109/L for 2 consecutive weeks during the treatment period, or achieving an increase in platelet count >20 × 109/L above baseline for 2 consecutive weeks during the treatment period was recorded. Results: A total of 22 (romiplostim, 17; placebo, 5) patients were randomized; 16 (73%) were boys and 6 (27%) were girls. Eight patients had undergone splenectomy. The mean age was 9.5 (SD: 5.1) years, with 4 subjects aged 12 months - <3 years, 10 aged 3 - <12 years, and 8 aged 12 - <18 years. The median baseline platelet count was 13 × 109/L (range 2 to 29 × 109/L) and the median duration of ITP was 2.4 years (range 0.6 to 14 years). All patients completed the study. Sixteen of 17 patients in the romiplostim arm (94%) and 5/5 in the placebo arm (100%) had at least 1 AE during the treatment period. The most common AEs were (romiplostim, placebo, respectively) headache (35%, 40%), epistaxis (35%, 20%), cough (12%, 40%), and vomiting (12%, 40%). Serious AEs were experienced by 1 patient in the romiplostim arm (moderate influenza and sepsis) and none in the placebo arm. AEs considered to be treatment related were reported for 3 (18%) and 1 (20%) subjects in the romiplostim and placebo arms, respectively; none of the treatment-related AEs were serious or of ≥3 grade severity. No patients died during the study and none tested positive for neutralizing antibodies to romiplostim or thrombopoietin. The same group of patients in the romiplostim-treated arm (15/17, 88.2%, 95% CI: 63.6%, 98.5%) achieved both efficacy endpoints during the treatment period. The median platelet count in the romiplostim-treated arm after 6 weeks of treatment was ≥50 × 109/L. The median weekly platelet count in the placebo arm remained stable at approximately 10 × 109/L. None of the placebo-treated patients achieved either platelet count endpoint. Rescue medication was administered to 2/17 (12%) of romiplostim- and 2/5 (40%) of placebo-treated patients during the 12 week treatment period. Twelve (71%) and 2 (40%) subjects in the romiplostim and placebo arms, respectively, experienced bleeding events. The majority of bleeding events (15/17) in the romiplostim arm occurred in the first 6 weeks of treatment. Most bleeding events (14/17) in the romiplostim arm and all bleeding events in the placebo arm occurred when the platelet count was < 30 × 109/L. A total of 14 patients treated with romiplostim entered the PK assessment period. The romiplostim serum concentration results were not different among the 3 age cohorts. The mean weekly dose of romiplostim in the treatment period was 3.4 (SD: 1.6) μg/kg. Conclusion: Treatment with romiplostim appeared to be well tolerated in pediatric ITP patients, with no new safety concerns observed in this study as compared to adults with chronic ITP. Romiplostim was effective in treating thrombocytopenia in children with chronic ITP. Disclosures: Buchanan: Amgen Inc.: Research Funding. Off Label Use: Use of romiplostim, a thrombopoietin mimetic, in treatment of thrombocytopenia in pediatric ITP patients. . Bomgaars:Novartis: Research Funding. Bussel:Eisai, Inc: Research Funding; Sysmex: Research Funding; Shionogi: Membership on an entity's Board of Directors or advisory committees; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Immunomedics: Research Funding; Amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; GlaxoSmithKline: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; Genzyme: Research Funding; Scienta: Speakers Bureau. Nie:Amgen Inc.: Employment, Equity Ownership. Eisen:Amgen Inc.: Employment, Equity Ownership. Berger:Amgen Inc.: Employment, Equity Ownership.

scholarly journals Predictors of Remission in Adults with Immune Thrombocytopenia Treated with Romiplostim

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 735-735
Author(s):  
Adrian Newland ◽  
James B. Bussel ◽  
Robert Bird ◽  
Donald M. Arnold ◽  
Craig M. Kessler ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Univariate Analysis ◽  
Newly Diagnosed ◽  
Employment Equity ◽  
Advisory Committees ◽  
Platelet Counts ◽  
Equity Ownership

Abstract Background: In adults with ITP, thrombopoietin receptor agonists (TPO-RA) are often assumed to be lifelong therapy. However, some patients achieve treatment-free remission (TFR) by maintaining hemostatic platelet counts after discontinuing TPO-RA, despite not replacing them with other ITP medications. Predictors of safely discontinuing romiplostim have varied across studies. In an analysis of 8 romiplostim studies, 27 patients achieved TFR; more remitters than nonremitters had ITP for <12 months but there were no unequivocal predictors of TFR (Bussel et. al. Hematology 2016;21:257). In a phase 2 study with forced romiplostim taper after 12 months, 24 (32%) of 75 patients achieved TFR; a higher platelet count in the first 2 months was associated with TFR (P<.05; Newland et. al. Br J Haematol 2016;172:262). Differences between remitters and nonremitters for baseline patient characteristics and time to first platelet response were not statistically significant. Analysis of romiplostim treatment at 2 centers found that 12 (28%) of 43 patients achieved TFR; splenectomized patients were more likely than nonsplenectomized patients to achieve TFR (P=.05; Marshall et. al. Haematologica 2016;101:e476). Aim: This multivariate analysis integrated data across multiple romiplostim studies in adults with ITP to explore predictors of TFR. Methods: Data were pooled for 911 romiplostim-treated patients in 13 ITP studies conducted from 2002 to 2014. All patients failed first-line treatments before study enrollment. Secondary thrombocytopenia patients were excluded. Romiplostim treatment was discontinued per dosing rules; 1 study included a forced taper after 1 year of romiplostim. Typically, the romiplostim dose was reduced for platelet counts >200×109/L and withheld, then reduced, for platelet counts >400×109/L. Concomitant ITP medication could be reduced for platelet counts >50×109/L. TFR was defined as a ≥6-month treatment-free period with platelet counts consistently ≥50×109/L. Univariate analysis with logistic regression examined potential predictors of TFR, including age, sex, ITP duration, prior splenectomy, platelet count (baseline and first 4 weeks), bleeding in the first 6 months, and baseline concurrent therapy. Multivariate analysis with logistic regression evaluated significant predictors from the univariate analysis. Results: TFR was achieved by 61 ITP study patients who received romiplostim. For remitters vs nonremitters, median baseline age was 53 years in both cohorts; 57% vs 61% were female; and 93% vs 88% were Caucasian (Table 1). Median ITP duration at study baseline was 0.5 years among remitters and 3.5 years among nonremitters. Prior splenectomy occurred in 21% of remitters and 36% of nonremitters. The number of prior ITP treatments was ≤3 for 74% of remitters and 39% of nonremitters. Baseline platelet count was <30×109/L for 80% of remitters and 78% of nonremitters. Median platelet counts on treatment during the romiplostim studies were often higher among remitters than nonremitters, despite increasing median doses of romiplostim over time for nonremitters (Figure). During the first 6 months on study, 30% of remitters and 43% of nonremitters had a bleeding event. Prior splenectomy and bleeding in the first 6 study months were significant predictors of lower odds of TFR in the univariate model but not in the multivariate model. In the multivariate model, shorter ITP duration predicted significantly higher odds of TFR, either <3 months (newly diagnosed) vs >12 months (chronic; odds ratio [OR], 4.275; P<.0001) or 3-12 months (persistent) vs chronic (OR, 2.171; P=.0408; Table 2). One limitation of this analysis was 19 of 61 patients entering TFR were from one study of newly diagnosed and persistent patients; the protocol included a forced romiplostim taper. Number of previous treatments was not included in the multivariate analysis. Conclusions: In this integrated analysis of 911 adult ITP patients across 13 studies, shorter ITP duration at baseline (≤12 months) was an independent predictor of TFR. Neither previous splenectomy (which predicted TFR in 1 study) nor bleeding were independent predictors of TFR in this much larger analysis. In total, these results imply that earlier use of romiplostim in adults with ITP could be associated with greater likelihood of achieving TFR. Future studies should also explore biologic variables as predictors of TFR. Disclosures Newland: Amgen Inc., Angle, Dova Pharmaceuticals, Argenx, Rigel, Shionogi, Novartis: Consultancy; Amgen Inc., GlaxoSmithKline, and Novartis: Research Funding; Novartis: Speakers Bureau. Bussel:Uptodate: Honoraria; Protalex: Consultancy; Momenta: Consultancy; Rigel: Consultancy, Research Funding; Prophylix: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Amgen Inc.: Consultancy, Research Funding. Bird:Amgen, Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Arnold:Novartis: Consultancy, Research Funding; UCB: Consultancy; UCB: Consultancy; Bristol Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding; Bristol Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding; Novartis: Consultancy, Research Funding. Kessler:Novo Nordisk: Honoraria, Research Funding; Biomarin: Research Funding; Genentech: Research Funding; Dimension Advisory boards: Membership on an entity's Board of Directors or advisory committees; DSMB: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sangamo: Research Funding; Bayer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Octapharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Mayer:Novartis: Research Funding; Amgen: Research Funding. Janssens:Roche: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Ad board, Speakers Bureau; Novartis: Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Speakers Bureau; Sanofi-Genzyme: Speakers Bureau; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Ad board, Speakers Bureau; Janssen: Consultancy, Speakers Bureau. Wang:Amgen: Employment, Equity Ownership. Eisen:Amgen Inc.: Employment, Equity Ownership.

Long-Term Treatment of Chronic Immune Thrombocytopenic Purpura with Oral Eltrombopag: Results From the EXTEND Study.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 682-682 ◽  
Author(s):  
Mansoor N. Saleh ◽  
James B. Bussel ◽  
Gregory Cheng ◽  
Balkis Meddeb ◽  
Bhabita Mayer ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Advisory Committees ◽  
Thrombocytopenic Purpura ◽  
Once Daily ◽  
Platelet Counts ◽  
Chronic Itp ◽  
Equity Ownership

Abstract Abstract 682 INTRODUCTION: Eltrombopag (PROMACTA; GlaxoSmithKline, Collegeville, PA) is the first oral, small molecule, thrombopoietin receptor agonist approved in the US for the treatment of chronic immune thrombocytopenic purpura (ITP). Eltrombopag is also being evaluated for the treatment of thrombocytopenia due to other causes (eg, hepatitis C, MDS). Chronic ITP is characterized by autoantibody-induced platelet destruction and reduced platelet production, leading to chronically low platelet counts. Eltrombopag has been shown to significantly increase platelet counts and reduce clinically relevant bleeding symptoms in 3 placebo-controlled ITP trials evaluating a total of 429 patients. EXTEND is an ongoing open-label, phase 3 extension study to assess the long-term safety and efficacy of eltrombopag in chronic ITP. METHODS: Patients with previously treated, chronic ITP who completed a prior eltrombopag study were eligible to participate in EXTEND. Eltrombopag treatment was initiated at 50 mg once daily and then adjusted to maintain platelet counts between ≥50,000/μL and <200,000/μL, with doses between 75 mg and 25 mg once daily (or less often if necessary). Patients who achieved platelet counts ≥50,000/μL were considered responders. Bleeding events were prospectively evaluated using the World Health Organization (WHO) Bleeding Scale: grade 0 = no bleeding, grade 1 = mild bleeding, grade 2 = moderate bleeding, grade 3 = gross bleeding, and grade 4 = debilitating blood loss. Bone marrow (BM) biopsy was required after 1 year on treatment. RESULTS: At the time of this analysis, 299 patients (median age 50 years; 66% female) had received eltrombopag (240, 126, 48, and 17 patients exposed for ≥6, 12, 18, and 24 months, respectively). The median duration of eltrombopag treatment was 204 days and ranged from 2–861 days. At baseline, 33% were receiving concomitant ITP medication and 38% had been splenectomized. The majority of patients (70%) had baseline platelet counts <30,000/μL, followed by 17% and 13% with baseline platelet counts from μ30,000/μL to <50,000/μL, and μ50,000/μL, respectively; all had baseline platelet counts <50,000/μL at the time of entry into their previous study. Overall, 86% of patients (257/299) achieved a platelet count μ50,000/μL. Splenectomized and non-splenectomized patients responded equally well (89% and 82%, respectively). Patients responded to eltrombopag regardless of baseline use of concomitant ITP medications (no baseline ITP medications and baseline ITP medications: 86% each). Median platelet counts increased to μ50,000/μL by week 2, and remained μ50,000/μL throughout the observation period of the study (Figure 1). Patients on treatment for μ6 months or μ12 months achieved platelet counts of μ50,000/μL and 2x baseline for 69% (18/26 weeks) and 71% (37/52 weeks) of the time on treatment, respectively. At baseline, 56% of patients reported bleeding symptoms (WHO grades 1–4) compared to 27%, 21%, 40%, and 25% at 6, 12, 18, and 24 months, respectively. Adverse events (AEs) were reported in 248 patients (83%) while on therapy, the majority being mild to moderate. The most common AEs reported were headache (23%), upper respiratory tract infection (17%), nasopharyngitis (17%), fatigue (13%), arthralgia (12%), and diarrhea (11%). Five deaths were reported: 2 occurred on therapy and 3 occurred more than 30 days posttherapy; none considered related to study medication. A total of 24 patients (8%) met any of the hepatobiliary laboratory abnormality screening criteria (ALT ≥3x ULN, AST ≥3x ULN, total bilirubin >1.5x ULN, or alkaline phosphatase >1.5x ULN). Thirteen patients (4%) experienced 16 thromboembolic events (TEEs); 11/13 (85%) experienced the event at a platelet count lower than the maximum platelet count achieved during eltrombopag treatment. Platelet counts proximal to the TEEs ranged from 14,000–407,000/μL. Eighty-six BM biopsies were performed. No clinically relevant effects of eltrombopag on BM were detected. CONCLUSION: Oral eltrombopag treatment for up to 2 years effectively raised platelet counts, decreased bleeding symptoms, and was generally well-tolerated in chronic ITP. Disclosures: Saleh: GlaxoSmithKline: Speakers Bureau; Amgen: Speakers Bureau. Bussel:Genzyme: Research Funding; GlaxoSmithKline: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Cangene: Research Funding; Amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding; Immunomedics: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eisai, Inc: Research Funding; Sysmex: Research Funding; Scienta: Speakers Bureau; Shionogi: Membership on an entity's Board of Directors or advisory committees. Cheng:GlaxoSmithKline: Research Funding. Mayer:GlaxoSmithKline: Employment. Bailey:GlaxoSmithKline: Employment. Aivado:GlaxoSmithKline: Employment.

Cumulative Response to Eltrombopag and Impact of the Number of Prior ITP Therapies: Interim Results of a Long-Term Extension Study,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3297-3297
Author(s):  
James B Bussel ◽  
Christine K Bailey ◽  
Andres Brainsky
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Employment Equity ◽  
Phase 3 ◽  
Advisory Committees ◽  
Platelet Counts ◽  
Chronic Itp ◽  
Equity Ownership

Abstract Abstract 3297 Background: Patients with chronic immune thrombocytopenia (ITP) have an increased risk of bleeding, ranging from minor to life-threatening. The goal of treatment is to increase and maintain platelets in a safe range to prevent bleeding. Guidelines state that achieving platelet counts of 30,000/μL to 50,000/μL in patients without other risk factors avoids the most serious complications of ITP, namely intra-cerebral or gastrointestinal hemorrhage (George 1996; Provan 2010). Many patients are refractory or relapse after multiple treatments. Eltrombopag is an oral, nonpeptide thrombopoietin receptor agonist approved for the treatment of chronic ITP. In 6-week, and 6-month, placebo-controlled trials in patients with heavily pre-treated chronic ITP, eltrombopag increased platelets and reduced bleeding and the need for concomitant ITP therapy (Bussel 2007; Bussel 2009; Cheng 2011). Long-term treatment with eltrombopag is being evaluated in EXTEND, an extension study in chronic ITP patients who completed a previous eltrombopag study (Saleh 2010). Aims: To analyze in EXTEND the ability of eltrombopag to increase platelet counts to ≥50,000/μL in >50% and >75% of assessments and to determine whether the number of prior ITP therapies influences this ability. Methods: Patients in EXTEND received eltrombopag or placebo in 1 of the following prior studies of eltrombopag in chronic ITP: a 6-week phase 2 (TRA100773A; Bussel 2007) or phase 3 (TRA100773B; Bussel 2009) study, a 6-month phase 3 study (RAISE; Cheng 2011), or a phase 3 study of intermittent treatment (REPEAT; Psaila 2008). Dosing in EXTEND is individualized in order to maintain platelet counts ≥50,000/μL and <200,000/μL while minimizing the use of concomitant ITP medications. For the purpose of this analysis, response is defined as a platelet count ≥50,000/μL. Results: Among the 299 patients enrolled in EXTEND between June 2006 and February 2010, 67 (22%), 73 (24%), 47 (16%), and 112 (37%) patients had received 1, 2, 3, and ≥4 prior therapies (excluding eltrombopag). The most commonly used prior therapies were corticosteroids (81%), IVIg (45%), splenectomy (38%), and rituximab (23%). Of the 299 patients enrolled, 70% achieved response in >50% of study assessments and 46% achieved response in >75% of assessments. Among 210 patients treated ≥12 months, 79% achieved response in >50% of assessments and 56% in >75% of assessments. Among 138 patients treated for ≥24 months, 82% achieved response in >50% and 59% in >75% of assessments. Response in >50% and >75% of assessments by the number of prior therapies was similar between the groups (Figure 1). The proportion of patients who achieved a response in >50% of assessments was similar between splenectomized and non-splenectomized patients (65% and 73%, respectively). Conclusion: The majority of patients treated with eltrombopag for ≥12 months achieved a platelet count of ≥50,000/μL in >50% of study assessments. This response was observed even among patients previously treated with 4 or more ITP therapies, suggesting that eltrombopag may be a viable treatment option even for more refractory chronic ITP patients. Disclosures: Bussel: Portola: Consultancy; Eisai: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; GlaxoSmithKline: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Amgen: Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Cangene: Research Funding; Genzyme: Research Funding; Immunomedics: Research Funding; Ligand: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Shionogi: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Sysmex: Research Funding. Bailey:GlaxoSmithKline: Employment, Equity Ownership. Brainsky:GlaxoSmithKline: Employment, Equity Ownership.

Efficacy, Hematologic Effects, and Dose of Ruxolitinib in Myelofibrosis Patients with Low Starting Platelet Counts (50–100 × 109/L): A Comparison to Patients with Normal or High Starting Platelet Counts

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 176-176 ◽  
Author(s):  
Moshe Talpaz ◽  
Ronald Paquette ◽  
Lawrence Afrin ◽  
Solomon Hamburg ◽  
Katarzyna Jamieson ◽  
...  
Keyword(s):  
Platelet Count ◽  
Board Of Directors ◽  
Research Funding ◽  
Phase Iii ◽  
Spleen Volume ◽  
Employment Equity ◽  
Advisory Committees ◽  
Platelet Counts ◽  
Equity Ownership ◽  
Eortc Qlq

Abstract Abstract 176 Background: Ruxolitinib (RUX) has demonstrated clinical benefit for patients with myelofibrosis (MF) with or without the JAK2V617F mutation at starting doses of 15 or 20 mg PO BID by alleviating symptoms, improving quality of life measures, reducing spleen volume and exhibiting an apparent increase in overall survival in the phase III placebo (PBO)-controlled COMFORT-I study. Reversible declines in platelet count and hemoglobin (Hgb) can occur with ruxolitinib but are rarely treatment-limiting. Patients with MF who have low platelet counts represent an important subset of MF patients; given the potential risk of bleeding complications, a dosing strategy for such patients is needed. We assessed an alternative strategy using lower starting doses of ruxolitinib with subsequent dose escalation in patients with MF who have platelet counts of 50–100 × 109/L (Study INCB018424-258; NCT01348490). Methods: RUX dosing started at 5 mg BID. With adequate platelet count, doses could increase by 5 mg once daily every 4 weeks to 10 mg BID. Further increases required evidence of suboptimal efficacy. Assessments include measurement of MF symptoms (MF Symptom Assessment Form v2.0 Total Symptom Score [TSS]); Patient Global Impression of Change (PGIC); EORTC QLQ-C30, measurement of spleen volume by MRI, and safety/tolerability. Results: A total of 50 patients have enrolled, with data available for 41 patients. Nineteen have completed 24 weeks of treatment; >70% of these patients attained a final dose of ≥10 mg BID of RUX. Treatment was generally well tolerated in this study population with no withdrawals for thrombocytopenia or bleeding events. Based on analysis of adverse events, no new safety signals were observed in this population of MF patients with low platelet counts. Data for efficacy parameters, including spleen volume reduction, TSS reduction, and improvement in EORTC-QLQ-C30 subscales and PGIC were consistent with RUX treatment in the COMFORT-I study, and demonstrated clinically meaningful efficacy compared with the COMFORT-I PBO arm (Table). Of 19 patients with platelet count data through Week 24, 5 showed increased platelet count over the duration of the study (range of increase: 20 to 95 x109/L); all 5 patients had optimized dosing to ≥10 mg BID. Compared with the 14 patients showing smaller increases or modest decreases in platelet count, these 5 patients were younger (mean age: 63 years vs. 71 years), had been diagnosed with MF more recently (2.2 years vs. 5.2 years) and had lower DIPSS scores (60% Intermediate-1; 20% Intermediate-2; 20% High vs. 0% Intermediate-1; 79% Intermediate-2; 21% High). Four patients (9.8%) reported adverse events of bleeding (excluding events related to bruising) of any grade (all events were Grade 1 except one Grade 2 hematochezia), consistent with previously reported hemorrhage frequency in the COMFORT-I study (16.8%, RUX; 12.6%, PBO). Conclusions: These preliminary findings suggest that a dosing strategy of a low starting dose of RUX with escalation to 10 mg BID may be appropriate in MF patients who have low platelet counts. Most patients were able to titrate to a dose of ≥10 mg BID of RUX, a dose showing efficacy for both spleen volume and patient-reported outcomes generally consistent with previously reported data from Phase III trials. An increase in platelet counts was observed in approximately one-fourth of patients who completed 24 weeks of RUX treatment. Escalation to, and subsequent maintenance of, a 10 mg BID dose of RUX also preserves both Hgb and platelet count which may be beneficial for MF patients with anemia or thrombocytopenia. Disclosures: Talpaz: Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding; Ariad: Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees, Research Funding; Teva: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees. Paquette:Incyte: Consultancy. Jamieson:Sunesis: Membership on an entity's Board of Directors or advisory committees; Blue Distinction Centers for Transplants BlueCross BlueShield Association: Consultancy. Lyons:Amgen: Consultancy, Research Funding; Incyte: Consultancy, Research Funding; Novartis: Research Funding. Tiu:Incyte: Honoraria, Speakers Bureau. Winton:Incyte Corporation: Consultancy, Honoraria. Odenike:Incyte: Membership on an entity's Board of Directors or advisory committees; Sanofi-Aventis:Membership on an entity's Board of Directors or advisory committees. Peng:Incyte: Employment, Equity Ownership. Sandor:Incyte: Employment, Equity Ownership. O'Neill:Incyte: Employment, Equity Ownership. Erickson-Viitanen:Incyte: Employment, Equity Ownership. Leopold:Incyte: Employment, Equity Ownership. Levy:Incyte: Employment, Equity Ownership. Kantarjian:Incyte Corporation: grant support Other. Verstovsek:Incyte Corporation: Research Funding.

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