Comparative Efficacy Among Chronic Phase-Chronic Myeloid Leukemia (CP-CML) Patients After Failure Of 2nd Generation Tyrosine Kinase Inhibitors (2G TKIs)

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4010-4010
Author(s):  
Jeff H. Lipton ◽  
Peter Bryden ◽  
Manpreet K Sidhu ◽  
Hui Huang ◽  
Lisa J McGarry ◽  
...  

Abstract Introduction Despite major advances in treatment, resistance and intolerance (R/I) continue to be a significant challenge in the management of CP-CML, with failure of commonly used 2G TKIs (dasatinib, nilotinib, bosutinib) occurring in >50% of patients over the course of treatment in the post-imatinib setting. Treatment options for patients who developed R/I to these 2G TKIs often had been limited to stem cell transplant or clinical trials. The availability of the new pharmacologic treatments has provided more options for patients in this setting. Ponatinib is the only TKI recommended to treat all TKI-resistant mutations listed in the National Comprehensive Cancer Network (NCCN) clinical practice guidelines, including the T315I mutation for which no other TKI is effective. However, the comparative efficacy of using ponatinib versus switching to a different pharmacologic treatment after 2G TKI failure has not been systematically examined. Methods A systematic review was conducted in MEDLINE, EMBASE and the Cochrane Libraries (2002-2012) as well as 3 conferences (ASH, ASCO, and EHA) over 5 years (2008-2012). Studies were included if they enrolled 10 or more adult patients and presented results for CP-CML patients who were R/I following 2G TKI treatment. All study designs were considered and no restriction was applied with respect to therapy dose, due to incomplete reporting of doses in the available studies. Reported cumulative response rates (regardless of time period of reporting) and derived confidence intervals from individual studies were plotted, with node size determined by number of patients in study arm. In addition, Bayesian methods were used to synthesize major cytogenetic response (MCyR) and complete cytogenetic response (CCyR) from individual studies and estimate the overall response probability with 95% credible interval (CrI) for each treatment. Bayesian analysis also was used to estimate the likelihood that each treatment offers the highest probability of CCyR/MCyR based on available evidence. Response probabilities for ponatinib were estimated using individual patient data from the phase 2 PACE study and published phase 1 study data. For the PACE study, only patients who had received 2 prior TKIs were included in the analysis, to provide an appropriate comparison to the published 2G TKI studies which included predominantly 3rd line patients. The base case analysis includes patients both with and without the T315I mutation; a sensitivity analysis focused on the subset of studies without substantial numbers of enrollees with the T315I mutation and those that presented subgroup results excluding patients with the mutation. Results 13 clinical trials and observational studies were included in the analysis. All studies reported CCyR and 8 reported MCyR. CCyR data from each study, with derived confidence intervals, are presented in Figure 1. Synthesized treatment-specific probabilities of CCyR across 2G TKIs ranged from 22.0% (bosutinib) to 26.9% (nilotinib) compared to 60.5% (95% CrI 52.1% to 68.6%) for ponatinib. Treatment-specific probabilities of MCyR across 2G TKIs ranged from 29.7% (bosutinib) to 49.9% (dasatinib or nilotinib) compared to 70.2% (62.1% to 77.7%) for ponatinib. CCyR and MCyR rates for omacetaxine were lower than those observed for both the 2G TKIs and ponatinib (9.9% and 19.8% respectively). The probability of ponatinib providing superior response to all other included treatments was estimated at 99.9% for CCyR and 97.4% for MCyR. Results in patients without the T315I mutation were similar: the probability of CCyR with ponatinib was 52.1% (41.9% to 62.4%) compared to 22.1% to 26.9% across 2G TKIs. The probability of MCyR with ponatinib was 64.2% (54.1% to 73.6%) compared to 29.7% to 50.0% across 2G TKIs. Conclusions The analysis suggests that CP-CML patients who are resistant or intolerant to prior 2G TKI therapies have higher complete (33.6 to 38.5 percentage points higher) and major (20.3 to 40.5 percentage points higher) cytogenic response with ponatinib compared with the 2G TKIs included in this analysis. Based on available data, ponatinib appears to provide a higher probability of treatment response compared to all other pharmacologic treatments commonly used in this indication. This observation was consistent both for the overall patient population and among the subset of patients without the T315I mutation. Disclosures: Lipton: Novartis: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol Myers Squibb: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ariad: Equity Ownership, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau. Bryden:Ariad Pharmaceuticals, Inc.: Research Funding. Sidhu:Ariad Pharmaceuticals, Inc.: Research Funding. Huang:Ariad Pharmaceuticals, Inc.: Employment. McGarry:Ariad Pharmaceuticals, Inc.: Employment; GSK: Consultancy; BMS: Consultancy; Pfizer: Consultancy; Janssen (J&J): Consultancy. Lustgarten:ARIAD: employees of and own stock/stock options in ARIAD Pharmaceuticals, Inc Other, Employment. Woods:Ariad Pharmaceuticals, Inc.: Research Funding. Hawkins:Ariad Pharmaceuticals, Inc.: Research Funding.

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4551-4551 ◽  
Author(s):  
Jeffrey H. Lipton ◽  
Dhvani Shah ◽  
Vanita Tongbram ◽  
Manpreet K Sidhu ◽  
Hui Huang ◽  
...  

Abstract INTRODUCTION Patients with chronic myeloid leukemia (CP-CML) failing 1st line imatinib are most commonly treated with the second-generation (2G) tyrosine kinase inhibitors (TKIs) dasatinib and nilotinib. However, for patients who experience resistance or intolerance (R/I) to 2G-TKIs in 2nd line, there currently is no consensus on the optimal therapy sequence for 3rd line treatment. The comparative efficacy of using ponatinib in the 3rd line after 2G TKI failure was examined in a previous study (Lipton et al., ASH 2013). This study assesses the comparative efficacy of ponatinib versus sequential treatment of alternate 2G TKIs in 3rdline setting in two separate patient populations, post-imatinib and dasatinib patients and post-imatinib and nilotinib patients. METHODS A systematic review was conducted in MEDLINE, EMBASE and the Cochrane Libraries (2002-2014), as well as 3 conferences (ASH (2008-2014), ASCO (2008-2014), and EHA (2008-2013)). Studies evaluating any TKI were included if they enrolled 10 or more post-imatinib adult patients with CP-CML who were also R/I to dasatinib or nilotinib. All study designs were considered and no restriction was applied with respect to therapy dose, due to incomplete reporting of doses in the available studies. Analyses was run on two groups of patients, those failing imatinib and dasatinib (Group Ima/Das) and those failing imatinib and nilotinib (Group Ima/Nil). Bayesian methods were used to synthesize major cytogenetic response (MCyR) and complete cytogenetic response (CCyR) from individual studies and estimate the overall response probability with 95% credible interval (CrI) for each treatment. Bayesian analysis also was used to estimate the likelihood that each treatment offers the highest probability of CCyR/MCyR based on available evidence. RESULTS Six studies evaluating bosutinib, nilotinib and ponatinib for Group Ima/Das (n= 419) and five studies evaluating bosutinib, dasatinib and ponatinib for Group Ima/Nil (n=83) were included in the analysis. All studies reported CCyR in both groups. Five studies evaluating bosutinib, nilotinib and ponatinib reported MCyR in Group Ima/Das and three studies evaluating bosutinib and ponatinib reported MCyR in Group Ima/Nil. Synthesized treatment-specific probabilities and 95% CrI for CCyR are presented in Figure 1. Synthesized treatment-specific probabilities of CCyR for Group Ima/Das were 27% for nilotinib, 20% for bosutinib and 54% (95% CrI 43%% to 66%) for ponatinib. Treatment-specific probabilities of MCyR for Group Ima/Das were 41% for nilotinib, 28% for bosutinib and 66% (95% CrI 55%% to 77%) for ponatinib. The probability of ponatinib providing superior response to all other included treatments for group Ima/Das was estimated to be >99% for both CCyR and MCyR. Synthesized treatment-specific probabilities of CCyR for Group Ima/Nil were 25% for dasatinib, 26% for bosutinib and 67% (95% CrI 51%% to 81%) for ponatinib. Treatment-specific probabilities of MCyR for Group Ima/Nil were 33% for bosutinib and 75% (95% CrI 60%% to 87%) for ponatinib. The probability of ponatinib providing superior response to all other included treatments for group Ima/Nil was estimated to be >99% for both CCyR and MCyR. CONCLUSIONS The post imatinib and dasatinib group included more studies with larger sample sizes compared with the post imatinib and nilotinib group. Overall, response rates appear higher for TKIs in the post imatinib and nilotinib group compared with the post imatinib and dasatinib group. For both groups, patients on ponatinib had higher CCyR and MCyR rates compared with the sequential 2G TKIs included in this analysis. Based on available data, ponatinib appears to provide a higher probability of treatment response for patients failing imatinib and dasatinib/ nilotinib compared with sequential 2G TKI therapy commonly used in this indication. Figure 1 Figure 1. Disclosures Lipton: Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Bristol Myers: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Ariad: Equity Ownership, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Shah:Ariad Pharmaceuticals: Research Funding. Tongbram:Ariad Pharmaceuticals: Research Funding. Sidhu:Ariad Pharmaceuticals Inc.: Research Funding. Huang:ARIAD Pharmaceuticals, Inc.: Employment, Equity Ownership. McGarry:ARIAD Pharmaceutical, Inc.: Employment, Equity Ownership. Lustgarten:ARIAD Pharmaceuticals Inc: Employment, Equity Ownership. Hawkins:Ariad Pharmaceuticals Inc.: Research Funding.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 644-644 ◽  
Author(s):  
Jorge Cortes-Franco ◽  
H. Jean Khoury ◽  
Franck Emmanuel Nicolini ◽  
Selim Corm ◽  
Jeffrey H. Lipton ◽  
...  

Abstract Abstract 644 Background: Omacetaxine is a first-in-class cetaxine with clinical activity against Ph+ CML and a mechanism of action independent of tyrosine kinase inhibition. Currently available tyrosine kinase inhibitors (TKIs) have not demonstrated activity in CML patients (Pts) who harbor the Bcr-Abl T315I mutation. Study Goals: To evaluate the safety and efficacy of subcutaneously (SC) administered omacetaxine in Pts with imatinib (IM)-resistant T315I+ Ph+ CML. Methods: Eligible Pts include adult CML Pts in chronic, accelerated, or blast disease phase (CP, AP, BP) with a confirmed Bcr-Abl T315I mutation and resistance to IM therapy. Induction schedule: 1.25 mg/m2 SC omacetaxine twice daily for 14 days every 28 days until hematologic response. Maintenance dosing: 1.25 mg/m2 SC omacetaxine twice daily for 7 days every 28 days. Study Results: To date, 90 Pts have been enrolled, with data available for analysis on 66 Pts (40 CP, 16 AP and 10 BP). The median age was 58 yrs (19-83) with 70% male Pts and a median disease duration of 54 mo (5-285). All Pts failed prior IM therapy, and 79% failed two or more prior TKIs. The presence of baseline T315I mutation was confirmed in all Pts. Baseline clonal evolution was evident in 10 (25%) CP, 6 (38%) AP, and 7 (70%) BP Pts. Eight CP Pts entered the study in CHR. The median follow-up for all Pts was 6.4 mo (0.2 to 29.6). Efficacy: In CP Pts, CHR was achieved in 26 Pts and maintained in 8 Pts for an overall CHR rate of 85%; the median duration of CHR was 7.7+ mo (1.7 to 23.6). Overall cytogenetic response was 27.5% with 6 (15%) Pts achieving a major cytogenetic response (MCyR, 4 complete, 2 partial). The median duration of MCyR was 6+ mo (0.8 to 16.1). Major molecular response was achieved in 15% of Pts and a reduction of baseline T315I mutated clone occurred in 56.7% of CP Pts. In AP Pts, overall hematologic response was achieved in 6 (37.5%) Pts with 5 CHR and 1 return to chronic phase (RCP). Median duration of response was 3.9+ mo (1.7 to 14.8). One AP Pt achieved a complete cytogenetic response; duration 1.9+ mo. In BP Pts, overall hematologic response was achieved in 3 (30%) Pts with 2 CHR and 1 RCP. The median overall survival for CP Pts has not been reached and 35 (88%) Pts were alive at the time of data cut- off. The median overall survival was 18.8 mo for AP and 1.8 mo for BP Pts. Median time to progression was 11.2, 3.1, and 1.2 mo for CP, AP, and BP Pts, respectively. Safety: Grade 3/4 related events occurred in 45 of 66 (68%) Pts. The most commonly reported events were thrombocytopenia (58%), anemia (36%) and neutropenia (33%). Non-hematologic toxicities were primarily grade 1/2 with the most frequently reported events of diarrhea (44%), fatigue (35%), pyrexia (32%), nausea (26%), and asthenia (21%). Grade 3/4 non-hematologic toxicities were uncommon with no events occurring in >5% of Pts and infection (3%) the most common event. Treatment delays occurred in approximately 50% of the Pts with median duration of approximately 12 days for all disease phases and cycles (CP=12, AP=10, and BP=12 days). The primary causes of delay were thrombocytopenia, neutropenia and pancytopenia. Sixteen deaths occurred during the study (5 CP, 4 AP, and 7 BP).Three deaths (1 CP, 1 AP, and 1 BP) were considered to have a possible relationship to omacetaxine: sepsis, pancytopenia, and sudden death with unknown cause, respectively. Conclusions: Omacetaxine administered by subcutaneous injection produces durable hematologic and cytogenetic responses with a safety profile consisting mainly of hematologic toxicities. Omacetaxine may provide a treatment option for this patient population who currently has no available approved drug therapies. Disclosures: Cortes-Franco: ChemGenex: Membership on an entity's Board of Directors or advisory committees, Research Funding. Khoury:ChemGenex: Membership on an entity's Board of Directors or advisory committees, Research Funding. Nicolini:ChemGenex: Research Funding. Corm:ChemGenex: Research Funding. Lipton:ChemGenex: Membership on an entity's Board of Directors or advisory committees, Research Funding. Jones:ChemGenex: Research Funding. Hochhaus:ChemGenex: Research Funding. Craig:ChemGenex: Employment. Benichou:ChemGenex: Employment. Humphriss:ChemGenex: Employment. Kantarjian:ChemGenex: Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3543-3543 ◽  
Author(s):  
Alexis A. Thompson ◽  
Mark C. Walters ◽  
Janet L. Kwiatkowski ◽  
Suradej Hongeng ◽  
John B. Porter ◽  
...  

Background Transfusion-dependent β-thalassemia (TDT) is treated with regular, lifelong red blood cell (RBC) transfusions and despite iron-chelating therapy, carries a risk of serious organ damage from iron overload and other complications. Transplantation with autologous CD34+ cells encoding a βA-T87Q-globin gene (LentiGlobin for β-thalassemia) is being evaluated in patients with TDT. Interim results are presented here from the ongoing, international, single-arm, phase 3 Northstar-2 study (HGB-207; NCT02906202) of LentiGlobin gene therapy in pediatric, adolescent, and adult patients with TDT (defined by receiving ≥100 mL/kg/yr of RBCs or ≥8 RBC transfusions/yr) and non-β0/β0 genotypes. Methods Patients undergo hematopoietic stem cell (HSC) mobilization with G-CSF and plerixafor. Following apheresis, CD34+ cells are transduced with BB305 lentiviral vector and infused into patients after pharmacokinetic-adjusted, single-agent busulfan myeloablation. The primary efficacy endpoint is transfusion independence (TI; weighted average hemoglobin [Hb] ≥9 g/dL without RBC transfusions for ≥12 months). HSC engraftment, βA-T87Q-globin expression, Hb levels, detection of replication competent lentivirus (RCL), and adverse events (AE) are also assessed. Patients are followed for 2 years and offered participation in a long-term follow-up study. Summary statistics are presented as median (min - max). Results Twenty patients were treated in Northstar-2 as of 13 December 2018 and have been followed for a median of 8.1 (0.5 - 22.2) months. At enrollment, median age was 16 (8 - 34) years; 5 patients were <12 years of age. Median drug product cell dose was 8.0 (5.0 - 19.9) x106 cells/kg and vector copy number was 3.2 (1.9 - 5.6) copies/diploid genome. Time to neutrophil and platelet engraftment in the 18/20 and 15/20 evaluable patients was 22.5 (13 - 32) and 45 (20 - 84) days, respectively. Non-hematologic grade ≥3 AEs in ≥3 patients after LentiGlobin infusion included stomatitis (n=12), febrile neutropenia (n=6), pyrexia (n=4), epistaxis (n=3), and veno-occlusive liver disease (n=3). One serious AE of grade 3 thrombocytopenia was considered possibly related to LentiGlobin. No patient died, had graft failure, or had detection of RCL. No insertional oncogenesis has been observed. Gene therapy-derived HbAT87Q stabilized approximately 6 months after infusion. In adolescent and adult patients treated with LentiGlobin, median HbAT87Q at Months 6, 12 and 18 was 9.5 (n=11), 9.2 (n=8), and 9.5 (n=3) g/dL, respectively. The median total Hb without transfusions at Months 6, 12, and 18 were 11.9 (n=11), 12.4 (n=8), 12.3 (n=2) g/dL, respectively. At Month 6, 91% (10/11) of patients had total Hb of >11 g/dL without transfusions. Five adolescent and adult patients were evaluable for the primary endpoint of transfusion independence, 4 (80%) of whom achieved TI. The median weighted average Hb during TI was 12.4 (11.5 - 12.6) g/dL which compared favorably to pre-transfusion nadir Hb levels before enrollment (median 9.1 g/dL [7.5 - 10.0 g/dL]). At time of analysis, the median duration of TI was 13.6 (12.0 - 18.2) months. One patient who did not achieve TI stopped transfusions for 11.4 months but resumed transfusions due to recurrent anemia. This patient had a 71.4% reduction in RBC transfusion volume from Month 6 to Month 18 compared to baseline. Marrow cellularity and myeloid:erythroid (M:E) ratios were evaluated in 8 adolescent and adult patients with ≥12 months follow-up to assess the effect of LentiGlobin treatment on dyserythropoiesis. Seven of 8 patients had improved marrow M:E ratios at Month 12 (0.63 - 1.90) compared with baseline (0.14 - 0.48). In patients who stopped transfusions, soluble transferrin receptor levels were reduced by a median of 72% (58% - 78%) at Month 12 (n=6). Updated outcomes in adolescents and adults and outcomes in pediatric patients will be reported. Summary In this update of the Northstar-2 study of LentiGlobin gene therapy in patients with TDT and non-β0/β0 genotypes, transfusion independence was observed in 4/5 evaluable adolescent and adults and 10/11 treated patients had total Hb of >11 g/dL without transfusion support 6 months after LentiGlobin infusion. HbAT87Q stabilized approximately 6 months after treatment and patients who stopped RBC transfusions had improved erythropoiesis. A safety profile consistent with busulfan conditioning was observed after LentiGlobin gene therapy. Disclosures Thompson: bluebird bio, Inc.: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Baxalta: Research Funding. Walters:TruCode: Consultancy; AllCells, Inc: Consultancy; Editas Medicine: Consultancy. Kwiatkowski:bluebird bio, Inc.: Consultancy, Research Funding; Terumo: Research Funding; Celgene: Consultancy; Agios: Consultancy; Imara: Consultancy; Apopharma: Research Funding; Novartis: Research Funding. Porter:Protagonism: Honoraria; Celgene: Consultancy, Honoraria; Bluebird bio: Consultancy, Honoraria; Agios: Consultancy, Honoraria; La Jolla: Honoraria; Vifor: Honoraria; Silence therapeutics: Honoraria. Thrasher:Rocket Pharmaceuticals: Consultancy, Membership on an entity's Board of Directors or advisory committees; Orchard Therapeutics: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Generation Bio: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees; 4BIOCapital: Membership on an entity's Board of Directors or advisory committees. Thuret:BlueBird bio: Other: investigators for clinical trials, participation on scientific/medical advisory board; Celgene: Other: investigators for clinical trials, participation on scientific/medical advisory board; Novartis: Other: investigators for clinical trials, participation on scientific/medical advisory board; Apopharma: Consultancy. Elliot:bluebird bio, Inc.: Employment, Equity Ownership. Tao:bluebird bio, Inc.: Employment, Equity Ownership. Colvin:bluebird bio, Inc.: Employment, Equity Ownership. Locatelli:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Bellicum: Consultancy, Membership on an entity's Board of Directors or advisory committees; bluebird bio: Consultancy; Miltenyi: Honoraria.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 42-43
Author(s):  
Brad S. Kahl ◽  
Anik R. Patel ◽  
Omer Zaidi ◽  
Sonya J. Snedecor ◽  
Anna G. Purdum

ABSTRACT Introduction: Patients with indolent non-Hodgkin lymphomas (iNHL), including follicular lymphoma (FL), have high response to first-line treatment. However, retreatment is often required when relapses occur, and those with multiple relapses represent a patient population with an unmet need for effective treatment. Clinical data for several treatment options exist for the general relapsed and refractory (R/R) population; however, there are relatively fewer data specific to FL patients with ≥2 lines of prior treatment. This work systematically identified the available efficacy data in the double R/R FL population. Methods: The MEDLINE and EMBASE databases were searched through February 10, 2020. Studies were limited to interventional clinical trials of R/R FL patients (or mixed histologies with a predominance of FL) and articles published in English. Studies also must have reported one or more efficacy measures, such as overall response rate (ORR), complete response (CR), duration of response (DoR), time to next treatment (TTNT), progression-free survival (PFS), and overall survival (OS). Potential interventions of interest were lenalidomide ± rituximab (R), duvelisib, ibrutinib, venetoclax, polatuzumab vedotin + R, obinutuzumab, copanlisib, umbralisib, idelalisib, and tazemetostat. Results: Of 35 publications examining treatment outcomes in R/R FL patients, only 14 (representing 5 unique clinical trials) were specific to the ≥ 2-line population. These trials were: CHRONOS Part B (copanlisib), DAWN (ibrutinib), DELTA (idelalisib), DYNAMO (duvelisib), and Morschhauser et al. 2019 (tazemetostat) and included a total of 605 participants. All studies used similar inclusion criteria, and patients included were similar in age (median 62-65), disease stage (III/IV), and ECOG score (0-2). Patients in the CHRONOS study had a median number of prior treatments of 2, whereas those in the DELTA study had 5. ORR ranged from 21% (ibrutinib) to 59% (copanlisib) (Table). The DoR ranged from 8.3 months in tazemetostat patients with EZH2 gene mutation to 19.4 months for ibrutinib. PFS ranged from 5.7 months in tazemetostat patients with wild-type EZH2 to 11.2 months for copanlisib. Median TTNT was only reported in the DAWN study (16 months). Conclusions: Very few clinical data exist reporting efficacy outcomes specific to the double R/R FL population. The limited data indicate that current treatments do not produce durable responses for most double R/R FL patients, demonstrating an unmet need. Further research is needed to fully understand the efficacy and safety of other potential interventions for this population. Disclosures Kahl: Genentech:Consultancy;Pharmacyclics LLC:Consultancy;AstraZeneca Pharmaceuticals LP:Consultancy, Membership on an entity's Board of Directors or advisory committees;ADC Therapeutics:Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Celgene Corporation:Consultancy;AbbVie:Consultancy;Roche Laboratories Inc:Consultancy;BeiGene:Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Janssen:Consultancy, Membership on an entity's Board of Directors or advisory committees;Acerta:Consultancy, Research Funding.Patel:Kite, a Gilead Company:Current Employment.Zaidi:BMS:Consultancy.Snedecor:Pharmerit - an OPEN Health Company:Other: Employment at consultancy paid by Kite Pharma to conduct this work.Purdum:Kite, a Gilead Company:Current Employment.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1130-1130 ◽  
Author(s):  
Jerald P. Radich ◽  
Giovanni Martinelli ◽  
Andreas Hochhaus ◽  
Enrico Gottardi ◽  
Simona Soverini ◽  
...  

Abstract Abstract 1130 Poster Board I-152 Background Nilotinib is a selective and potent BCR-ABL inhibitor, with in vitro activity against most BCR-ABL mutants (excluding T315I) indicated for the treatment of patients with Philadelphia chromosome positive (Ph+) CML in CPor AP resistant or -intolerant to prior therapy, including imatinib. In a previous analysis of nilotinib in patients with BCR-ABL mutations, mutations occurring at three specific amino acid residues (E255K/V, Y253H, and F359C/V) were shown to be associated with less favorable response to nilotinib. The current analysis is based on mature data with a minimum follow-up of 24-months for all patients. Outcomes of patients at 24 months were analyzed by mutation type. Methods Imatinib-resistant CML-CP (n = 200) and CML-AP (n = 93) patients were subdivided into the following mutational subsets: no mutation, sensitive mutations (including mutations with unknown in vitro IC50). or E255K/V, Y253H, or F359C/V mutations at baseline. Patients with mutations of unknown in vitro sensitivity were classified as sensitive in this analysis based on a previous finding that patients with these mutations responded similarly to nilotinib as patients with sensitive mutation. Patients with baseline T315I mutations were excluded from this analysis. Patient groups were analyzed for kinetics and durability of cytogenetic and molecular response to nilotinib, as well as event-free survival (EFS), defined as loss of hematologic or cytogenetic response, progression to AP/BC, discontinuation due to disease progression, or death, and overall survival (OS). Results In CML-CP and -AP patients with no mutation, sensitive mutations, or E255K/V, Y253H, or F359C/V mutations, hematologic, cytogenetic and molecular responses are provided in the Table. Overall, patients with no mutations responded similarly to patients with sensitive mutations, whereas patients with E255K/V, Y253H, or F359C/V mutations had less favorable responses. This correlation was observed in both CML-CP and CML-AP patients, respectively. Median time to CCyR was 3.3 months (range, 1.0–26.7) for CML-CP patients with no mutations, and 5.6 months (range, 0.9–22.1) for patients with sensitive mutations. At 24 months, CCyR was maintained in 74% of CML-CP patients with no mutation and in 84% of patients with sensitive mutations. One patient with CML-CP and an E255K mutation achieved CCyR at 25 months and maintained until last assessment at 30 months. Median time to MMR was similar at 5.6 months (range, 0.9–25.8) for CML-CP patients with no mutations and 5.6 months (range, 2.7–22.1) for patients with sensitive mutations. No patient with a less sensitive mutation achieved MMR. Median EFS and 24-month estimated OS rate are provided in the Table. Conclusions Imatinib-resistant CML-CP and CML-AP patients treated with nilotinib therapy with BCR-ABL mutations (excluding E255K/V, Y253H, or F359C/V) achieved rapid and durable cytogenetic responses, and estimated EFS and OS at 24 months similar to that of patients with no mutations, respectively. Patients with E255K/V, Y253H, or F359C/V mutations had lower and less-durable responses and shorter EFS than patients with sensitive mutations. Alternative therapies may be considered for patients with these uncommon mutations (E255K/V, Y253H, and F359C/V). Disclosures Radich: Novartis: Consultancy, Honoraria, Research Funding. Hochhaus:Novartis: Research Funding. Branford:Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding. Shou:Novartis: Employment. Haque:Novartis: Employment. Woodman:Novartis: Employment. Kantarjian:Novartis: Research Funding. Hughes:Bristol-Myers Squibb: Advisor, Honoraria, Research Funding; Novartis: Advisor, Honoraria, Research Funding. Kim:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Wyeth: Research Funding. Saglio:Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1125-1125 ◽  
Author(s):  
Michael P Osborn ◽  
Susan Branford ◽  
Deborah L White ◽  
John F Seymour ◽  
Ruth Columbus ◽  
...  

Abstract Abstract 1125 Poster Board I-147 The Australasian Leukaemia and Lymphoma Group conducted a trial (TIDEL I) in 103 patients with newly diagnosed chronic phase CML, using imatinib 600 mg/day with dose escalation to 800 mg/day for suboptimal response. This was defined as failure to achieve (1) complete haematological response (CHR) at 3 months, (2) major cytogenetic response (MCR) at 6 months, (3) complete cytogenetic response (CCR) or molecular equivalent at 9 months, or (4) less than 0.01% (IS) BCR-ABL by RQ-PCR at 12 months. Here we report the outcomes with all surviving patients having been treated for at least 60 months. We aimed to determine whether the patient outcome at 60 months was predicted by the molecular response within the first 18 months of imatinib therapy. The outcomes for patients maintaining a dose of imatinib of ≥600 mg/day in the first 12 months was compared to those who were on a reduced dose for at least part of this time. Event-free survival (EFS) was defined as death from any cause, accelerated phase/blast crisis (AP/BC), and loss of CHR, MCR or CCR. The 103 patients included 66 males and 37 females with a median (±SD) age of 49 (±14) years. All patients had an ECOG performance status of 0-2 at enrolment. The 5-year EFS was 71%, transformation (AP/BC) free survival (TFS) was 95%, and overall survival was 87%. Of the 14 patients who died, 3 died in blast crisis, 2 from transplant-related complications, 8 from CML-unrelated causes, and the cause of death of 1 patient was unavailable. The annual rates of progression to AP/BC over 5 years were 3%, 1%, 0%, 1%, and 0%, while annual event rates were 13%, 8%, 8%, 1%, and 4%. CCR was achieved by 89% of patients by 60 months, while 72% achieved a major molecular response (MMR) by this time. In the first 12 months of treatment, 55% of patients maintained an imatinib dose of ≥600 mg/day (mean ±SD dose = 604 ±10 mg/day), while 45% were on <600 mg/day for at least part of this time (mean ±SD dose = 511 ±100 mg/day). EFS at 60 months was significantly higher in patients taking ≥600 mg/day compared with those who had been dose-reduced to <600 mg/day (89% vs 56%, P<0.001). Annual event rates for the ≥600 mg/day group were 6%, 2%, 2%, 0%, and 2%, while annual event rates for those on <600 mg/day were 14%, 16%, 16%, 8%, and 4%. By 60 months, 96% of patients who had been on ≥600 mg/day within the first 12 months had achieved CCR, while only 80% of those who had been on <600 mg/day had achieved this milestone (P<0.001). Log rank analysis of the achievement of MMR was also significant (P=0.03). Overall survival and TFS after 12 months were both similar between the dosing groups. There was no difference between the dosing groups' median age (50 vs 48 years, P=0.36) or Sokal score (1.04 vs 0.94, P=0.33) that may otherwise account for these results. The outcome was also determined for all patients dependent on the BCR-ABL levels at various assessment timepoints. Patients with a BCR-ABL level of <10% (IS) at 6 months (n=92) had an EFS of 78% at 60 months, while all of those with a level >10% (IS) (n=8) had an event (P<0.001). Patients with a level of ≤1% (IS) at 12 months (equivalent to CCR) (n=81) had an EFS of 75% compared with 25% (n=13) for those with levels >1% (IS) (P<0.001). At 18 months, a level ≤0.1% (IS) (n=58) conferred an EFS of 88%, while those who had failed to attain this depth of response (n=30) had an EFS of 60%. There was a significant difference in EFS between those who had achieved an MMR at 18 months and those who had achieved a CCR, but no MMR (88% vs 67%, P=0.03). In conclusion, our data suggest that patients maintaining a dose of ≥600mg in the first 12 months of imatinib therapy are more likely to achieve CCR and MMR, and superior EFS compared to those with a lower dose. This study also confirms that achieving an MMR by 18 months is associated with improved EFS. This emphasises the value of achieving a molecular response early in the treatment course, as well as adding weight to the evidence supporting the role of molecular monitoring in CML. Disclosures Branford: Novartis Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: Honoraria, Research Funding. White:Novartis and Britol-Myers Squibb: Research Funding. Seymour:Bayer Schering: Consultancy, Membership on an entity's Board of Directors or advisory committees, Travel grants; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Travel Grants. Catalano:Roche: Honoraria, Research Funding, Travel grants. Mills:Celgene Pty Ltd: Honoraria, Membership on an entity's Board of Directors or advisory committees. Hughes:Bristol-Myers Squibb: Advisor, Honoraria, Research Funding; Novartis: Advisor, Honoraria, Research Funding.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3286-3286 ◽  
Author(s):  
Philipp D. le Coutre ◽  
Anna Turkina ◽  
Dong-Wook Kim ◽  
Bernadeta Ceglarek ◽  
Giuliana Alimena ◽  
...  

Abstract Abstract 3286 Poster Board III-1 Introduction: Nilotinib, a potent and highly selective BCR-ABL kinase inhibitor, is approved for the treatment of patients (pts) with Philadelphia chromosome-positive chronic myelogeneous leukemia (Ph+ CML) in chronic phase (CML-CP) and accelerated phase (CML-AP) who are resistant or intolerant to prior therapy including imatinib. The ENACT study is a Phase IIIb, open-label, multicenter study that evaluated the efficacy and safety of nilotinib in adult pts with imatinib-resistant or intolerant CML in a clinical practice setting outside of a registration program. It is the largest single source of efficacy and safety information of any available tyrosine kinase inhibitor (TKI) in CML, particularly among the elderly. Methods: The present is a sub-analysis of the ENACT study on the efficacy and safety of 400 mg twice daily nilotinib in elderly (aged =60 years) pts initiating treatment in CML-CP who were resistant and/or intolerant to imatinib. Results: Of the 1,422 CML-CP pts enrolled in the ENACT study between January 2006 and October 2008, 452 (32%) were elderly (=60 years) at study initiation and 165 (37%) of these pts were =70 years [10 (2%) were =80 years]. Countries that enrolled =20 elderly pts include France, Italy, USA, Germany, UK, Spain, Canada, and Brazil. At study initiation, elderly pts had longer median durations of CML (<60: 51.1 months; =60: 69.3; =70: 66.6) and higher proportions with CML duration >5 years (<60: 43%; =60: 56%; =70: 52%). Besides imatinib, prior CML treatments received by elderly pts included dasatinib (=60: 20%; =70: 19%), cytarabine (=60: 23%; =70: 19%), busulfan (=60: 10%; =70: 7%), and interferons (=60: 50%; =70: 42%). Elderly pts were previously treated with imatinib for longer median durations (<60: 27.4 months; =60: 32.7; =70: 29.9), with higher proportions treated for >5 years (<60: 12%; =60: 19%; =70: 18%). The proportion of imatinib-intolerant to resistant elderly pts was about 1:1, which was higher than the proportion among <60 pts at about 0.6:1, such that relatively few elderly pts had prior highest imatinib dose >800 mg (<60: 34%; =60: 26%; =70: 21%). While response rates to prior imatinib were similar, among pts who required therapy after failing imatinib, elderly pts had lower cytogenetic response rates (<60: 22%; =60: 17%; =70: 19%) to prior dasatinib. During ENACT, less than 50% of elderly pts experienced nilotinib dose interruptions (=60: 46%; =70: 41%) and reductions (=60: 7%; =70: 6%) lasting >5 days, which was consistent with the overall ENACT dataset. The median duration of dose interruptions and reductions was 15 (=70: also 15) and 41 (=70: 32) days, respectively. The main reason for dose interruptions and reductions was adverse events (AEs). The median duration of nilotinib exposure was 227 days (=70: 219) and the median dose intensity was 749 mg/day (=70: 775). Efficacy was similar among elderly pts, with 39% (=70: 35%) of pts achieving complete hematologic response (CHR), 41% (=70: 39%) achieving major cytogenetic response (MCyR) and 31% (=70: 33%) achieving complete cytogenetic response (CCyR). MCyR rate was also similar among elderly hematologic responders (=60: 64%; =70: 65%). Among elderly pts requiring nilotinib therapy after both imatinib and dasatinib, and therefore have more resistant CML, CHR rate was 39% (=70: 32%), MCyR rate was 28% (=70: 29%) and CCyR rate was 20% (=70: 16%). Safety was likewise similar among elderly pts, with grade 3/4 study drug-related AEs occurring in 56% of pts (=70: 53%). The most frequent of these AEs were thrombocytopenia (=60: 24%; =70: 21%) and neutropenia (=60: 14%; =70: 11%). The most common method of managing these AEs was brief dose interruptions and/or reductions [thrombocytopenia (=60:86/108 pts; =70: 30/35), neutropenia (=60: 42/62 pts; =70: 9/18)]. Among elderly pts with prior dasatinib, 53% (=70: 58%) experienced grade 3/4 study drug-related AEs, while 7 out of 8 pts with pleural effusion on dasatinib no longer had it on nilotinib. Conclusions: In ENACT, pts aged =60 years at study initiation appear to have longer durations of CML, be more heavily pre-treated and more intolerant to imatinib than the younger cohort. Nonetheless, nilotinib induced comparable clinical responses in CML-CP pts regardless of age. Importantly, the safety profile of nilotinib is maintained in elderly pts. Disclosures: le Coutre: Novartis: Honoraria, Research Funding; BMS: Honoraria. Turkina:Novartis Pharmaceuticals: Honoraria. Kim:Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Wyeth: Research Funding. Ceglarek:Novartis Pharmaceuticals: Honoraria. Shen:Novartis Pharmaceuticals: Honoraria. Smith:Novartis Pharmaceuticals: Honoraria. Rizzieri:Novartis Pharma: Honoraria, Research Funding, Speakers Bureau. Szczudlo:Novartis: Employment. Berton:Novartis Pharmaceuticals: Employment. Wang:Novartis Pharmaceuticals: Employment. Wang:Novartis Pharmaceuticals: Research Funding. Nicolini:Novartis Pharma: Consultancy, Honoraria, Research Funding, Speakers Bureau; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding, Speakers Bureau; Chemgenex: Honoraria, Speakers Bureau.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1518-1518
Author(s):  
Hun Ju Lee ◽  
Susan O'Brien ◽  
Hagop M. Kantarjian ◽  
Farhad Ravandi ◽  
Stefan Faderl ◽  
...  

Abstract Abstract 1518 Background: Treatment with TKIs has greatly improved the outcome of patients with Ph+ ALL. However, many patients treated with TKI-based therapy eventually have a relapse. The response to salvage therapy and long-term outcomes of these patients are unknown. Aims: Describe the outcomes of patients with Ph+ ALL with resistance to or relapse after frontline TKI-based chemotherapy. Methods: We analyzed the outcome of patients who were treated in clinical trials at our institution between February 2001 and July 2008 with TKI-based chemotherapy for newly diagnosed Ph+ ALL who had refractory or relapsed disease. Results: One hundred thirteen patients were treated with frontline hyperfractionated cyclophosphamide, doxorubicin, vincristine, and dexamethasone (HCVAD) plus imatinib (HCVAD+I; n=54) or HCVAD plus dasatinib (HCVAD+D; n=59). Of these, 35 (31%) experienced primary resistance (n=1) or relapse (n=34). The median age was 51 years [range (r): 20–85]; 12 patients (34%) were older than 60 years. Median follow-up was 21.1 mo (r: 4.2–56.7). Median white blood cell and platelet counts at diagnosis were 14.4 × 109/L (r: 1.2–292.9) and 48 × 109/L (r: 4–425), respectively. White blood cell count was >30 × 109/L in 13 patients (37%). Median peripheral and bone marrow blast percentages were 53% (r: 0–97%) and 80% (r: 1–98%), respectively. Twenty-two patients (63%) had received HCVAD+I and 13 (37%) HCVAD+D. Twenty-three patients (66%) had experienced first complete remission (CR1) with 1 cycle of induction. Median CR1 duration was 12 mo (r: 1.9–42). Four patients underwent allogeneic stem cell transplantation (ASCT) in CR1. ABL kinase domain mutations were investigated in 28 patients (80%) at relapse; 16 (57%) had mutations, including 5 (14%) with T315I (all had received HCVAD+D). Upon relapse, 31 patients received first salvage therapy (S1), 24 with chemotherapy [HCVAD+D, n=8; HCVAD+I, n=3; HCVAD+nilotinib (N), n=1; HCVAD+asparaginase (Asp), n=1; methotrexate, vincristine, Asp, and dexamethasone (MOAD), n=2; others, n=9]; 6 with a TKI only (I, n=2; D, n=1; N, n=1; others, n=2); and 1 with ASCT. Three patients were unfit for treatment. Median cycles of S1 were 2 (r: 1–8). Thirteen patients (42%) had second complete remission (CR2) (HCVAD+D, n=6; HCVAD+I, n=2; HCVAD+N, n=1; HCVAD+Asp, n=1; others, n=3). Median time to CR2 was 1.5 mo (r: 0.7–8.8). Five patients underwent ASCT in CR2. Median CR2 duration was 7.3 mo (r: 1.4–36.2). Complete cytogenetic response was seen in 11 patients (35%); major molecular response (BCR-ABL/ABL ratio <0.05%) in 9 (29%); and complete molecular response in 7 (22%); and complete hematologic response in 15 (48%). Times to complete cytogenetic response and complete molecular response were 1.3 mo (r: 0.7–10.6) and 3 mo (r: 1.5–8.7), respectively. Seven patients had second relapse. Fifteen patients (7 relapse, 8 refractory) received second salvage therapy (S2) with systemic chemotherapy (MOAD, n=2; phase I/single-agent TKI, n=8; others, n=5); 1 patient had solitary central nervous system (CNS) relapse treated with intrathecal cytarabine and methotrexate. CR3 was obtained in 1 patient, the patient with sole CNS relapse. Median disease-free survival (DFS) and overall survival (OS) after S1 were 6.5 mo (r: 0.5–45) and 7.3 mo (r: 1.4–36.2), respectively. At last follow-up, 2 patients (6%) were alive and 33 had died, 11 (33%) of infectious complications, 5 (15%) of organ failure, 3 (9%) of bleeding complications, 2 (6%) of graft-versus-host disease complications, 2 (6%) of CNS relapse, and 10 (30%) of other or unknown causes. Median OS after S2 was 2.1 mo (r: 1.4–2.6). In univariate analysis, age >60 years was associated with worse OS after S1 [4.2 vs. 12.7 mo; 95% confidence interval (CI) 1.8 to 6.7 vs. 7.5 to 17.9 (P=0.006)]. Complete hematologic response was associated with improved OS after S1 [15.4 vs. 4.3 mo; 95% CI 9.1 to 21.8 vs. 2.5 to 6.0 (P<0.001)]. Major molecular response was associated with improved OS after S1 [18.1 vs. 5.7 mo; 95% CI 9.3 to 26.8 vs. 3.6 to 7.8 (P=0.003)]. Choice of prior TKI (HCVAD+I vs. HCVAD+D) did not significantly influence CR and OS after relapse. Conclusion: Patients with refractory or relapsed Ph+ ALL after TKI-based therapy have poor outcome, particularly those who are older or have persistent BCR/ABL transcripts. New agents are needed to improve the outcome in this population. Disclosures: Kantarjian: BMS: Research Funding. Ravandi:Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Honoraria. Cortes:Chemgenex: Membership on an entity's Board of Directors or advisory committees, Research Funding; Ariad: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol-Myers Squibb: 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.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1645-1645 ◽  
Author(s):  
Carol Moreno ◽  
Marco Montillo ◽  
Panayiotidis Panayiotis ◽  
Adrian Bloor ◽  
Jehan Dupuis ◽  
...  

Abstract Background Ofatumumab was given a conditional approval in the EU on April 2010 for the treatment of CLL refractory to fludarabine (F-ref) and alemtuzumab (A-ref), encouraging the retrieval of further data in patients treated in a “daily life” setting and to investigate treatment safety. Aims The main objective of this study was to obtain information on the safety profile of ofatumumab given outside clinical trials in patients with previously treated CLL. The secondary endpoints were efficacy, progression-free-survival (PFS), and overall survival (OS). Methods This was an observational, retrospective study. Patients were eligible regardless of prior treatments or disease status and provided they had not been included in ofatumumab clinical trials. Data on patients’ characteristics at diagnosis, prior treatment, adverse events response rate, PFS and OS were recorded. Results One-hundred and twenty patients were screened of which 103 from 25 centers in 10 European countries were eventually eligible for the study. There were 71 males; median age at initiation of ofatumumab was 64 years (range, 38-84); 66% patients were in advanced clinical stage (Rai III-IV/Binet C) and 33 patients presented bulky lymphadenopathy. Number of prior lines of therapy was 4 (range, 1-13). 94% had received prior F-based therapy, 54% received A-based therapy and 51% received both. Eighty-one percent had been previously exposed to rituximab-combination regimens. Fifty-four percent were F-ref, 70% A-ref and 41% were both F- and A-refractory. Cytogenetics within 3 months prior therapy was available in 52 patients of which 34 presented abnormalities (11 patients: 17p-; 9 patients: 11q-; 2 patients: 13q-; 1 patient: trisomy 12; 11 patients: two or more abnormalities including 17p- or 11q-). Forty-two of 50 patients showed unmutated IGHV genes. The median number of cycles of ofatumumab given was 9 (range, 0-16) and the median percentage of given/planned cycles was 83.3% (range, 0-133). In most patients the treatment dose and schedule were as follows: 300 mg 1st infusion followed by 2000 mg for subsequent infusions (8 weekly followed by 4 doses monthly). One hundred and sixty-one adverse events were reported in 68 patients, with 28 (17%) of them being considered as ofatumumab-related. Infusion related-reactions occurred in 19 (28%) patients (III-IV: 6%). Neutropenia was reported in 26% (III-IV: 19%), thrombocytopenia in 15% (III-IV: 12%) and anemia in 15% (III-IV: 7%). The non-hematological adverse events, included infection 44% (III-IV: 36%), fatigue 10% (III-IV: 4%), fever 10% (III-IV: 6%), rash 10% (III-IV: 3%), cough 7% (III-IV: 1%), diarrhea 6% (grade III-IV: 0%) and nausea 1% (III-IV: 0%). Hematologic toxicity correlated with the number of prior lines of therapy. Autoimmune hemolytic anemia and Richter syndrome were reported in one patient each. Two heavily pre-treated patients (5 and 6 prior lines of therapy, respectively) developed progressive multifocal leukoencephalopathy. The overall response rate (ORR) was 23% and the median PFS and OS were 5 and 12 months, respectively. The main causes of death were disease progression (61%) and infection (28%). Conclusions The safety profile of ofatumumab given outside clinical trials to patients with poor-prognosis and heavily pre-treated CLL was consistent with that observed in clinical trials. Although not unexpectedly the ORR was lower in this study, PFS and OS were in line with those reported in phase II trials. Disclosures: Montillo: Roche: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; GSK: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Mundipharma: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding. Bloor:GSK: Consultancy, Honoraria, Paid speaker Other. Schuh:GSK: Honoraria; Celgene: Honoraria; Mundipharma: Honoraria. Geisler:Roche: Consultancy; GSK: Consultancy. Hillmen:GlaxoSmithKline: Honoraria, Research Funding. Stilgenbauer:GSK: Honoraria, support Other. Smolej:GSK: Consultancy, Honoraria, travel grants Other. Jaeger:GSK: Honoraria, Research Funding. Leblond:Roche : Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau; Janssen: Honoraria, Membership on an entity’s Board of Directors or advisory committees; Mundipharma: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Speakers Bureau. Kimby:Roche: Consultancy, Honoraria, Research Funding; celgene: Consultancy, Honoraria, Research Funding; Teva: Consultancy, Honoraria, Research Funding; Emergent BioSolutions: Consultancy, Honoraria, Research Funding; Gilead Sciences: Consultancy, Honoraria, Research Funding; Jansen: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria, Research Funding.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 270-270
Author(s):  
Julia E. Maxson ◽  
Jason Gotlib ◽  
Daniel A. Pollyea ◽  
Angela G. Fleischman ◽  
Anupriya Agarwal ◽  
...  

Abstract Background We have recently identified mutations in Colony Stimulating Factor 3 Receptor (CSF3R, aka GCSFR) in ∼60% of chronic neutrophilic leukemia (CNL) and atypical chronic myeloid leukemia (aCML) patients (Maxson et al, NEJM 2013). These mutations fall into two categories: membrane proximal point mutations (the most common of which is T618I) and truncation mutations. Drug and siRNA screening of primary patient samples revealed that the two classes of CSF3R mutations exhibit differential sensitivity to inhibition of SRC or JAK kinases. CSF3R truncation mutations conferred sensitivity to SRC family kinase inhibition, while CSF3R membrane proximal mutations (T618I) conferred sensitivity to JAK kinase inhibition. A patient with the T618I membrane proximal mutation responded to treatment with the FDA approved JAK inhibitor, ruxolitinib. CSF3R truncation mutations have also been observed in a subset of severe congenital neutropenia patients who are at high risk for development of acute myeloid leukemia. Prior studies in this context have shown that truncation mutations result in loss of endocytic and degradation motifs, leading to increased expression of the receptor. The differences in signaling and drug sensitivity of these mutation classes suggest that membrane proximal mutations may activate CSF3R signaling through a distinct, as-yet unknown mechanism. Furthermore, a subset of CNL patients harbor both membrane proximal and truncation mutations on the same allele, though the consequences of these compound mutations are not yet known. Methods CSF3R expression level and banding pattern were assessed by immunoblot of lysates from 293T17 cells transfected with wild type, membrane proximal mutant, or truncation mutant CSF3R. O-linked glycosylation was removed from the receptor by treatment with O-glycosidase and neuraminidase. Ligand independence of the CSF3R mutants was analyzed in murine interleukin-3 (IL3)-dependent Ba/F3 cells. CSF3R dimerization was assessed by co-transfecting CSF3R-Flag and CSF3R-V5 tagged constructs and then immunoprecipitating CSF3R-Flag and detecting co-immunoprecipitation of the CSF3R-V5 by immunoblot. Transforming potential of the CSF3R compound mutations relative to the corresponding point or truncation mutations was assessed by analyzing IL3-independent growth of Ba/F3 cells or mouse bone marrow colony formation. Results To better understand the functional and biochemical differences between membrane proximal and truncation mutant CSF3R, we examined transformation potential, requirement for ligand, and expression patterns in Ba/F3 and 293T17 cells. We found membrane proximal mutations to exhibit rapid transformation potential and ligand independence, while truncation mutations exhibited delayed transformation and ligand hypersensitivity. Unlike the truncation mutations, which induce dramatic overexpression of CSF3R, the T618I mutation did not result in overexpression of the receptor but instead induced a shifted banding pattern, indicative of altered protein modification. We examined the amino acid sequence surrounding the membrane proximal mutations and found residue T618 to be part of a consensus motif for O-glycosylation, wherein wild type CSF3R is O-glycosylated and the T618I mutation abrogates this O-glycosylation event. Furthermore, the T618I mutation exhibited increased receptor dimerization compared to wild type CSF3R, which likely explains its ligand independence. Finally, we found that CSF3R compound mutations have increased transforming potential in Ba/F3 and murine bone marrow colony assays compared with either class of single mutation, further underscoring the different mechanisms of action of the membrane proximal and truncation mutations. Conclusion CSF3R represents a promising therapeutic target for patients with CNL. We show that T618I, the most common CSF3R mutation in CNL, is part of an O-linked glycosylation site. Mutation of this residue leads to loss of O-linked glycosylation and represents a novel mechanism of homodimeric cytokine receptor activation. CSF3R compound mutations are more rapidly transforming relative to the membrane proximal or truncation mutations alone, warranting their further investigation for patient prognosis and therapy. Disclosures: Off Label Use: Ruxolitinib - a JAK1/2 inhibitor that we propose can be used off-label for disease management of CSF3R-mutant neutrophilic leukemia. Gotlib:Incyte: Membership on an entity’s Board of Directors or advisory committees, Research Funding, Travel Support Other. Fleischman:Incyte: Speakers Bureau. Collins:Genoptix: Membership on an entity’s Board of Directors or advisory committees. Oh:Incyte Corporation: Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau. Deininger:Novartis: Advisory Boards, Advisory Boards Other, Consultancy, Research Funding; Ariad Pharmaceuticals: Advisory Boards, Advisory Boards Other, Consultancy; Bristol-Myers Squibb: Advisory Boards Other, Consultancy, Research Funding; Celgene: Research Funding; Gilead Sciences: Research Funding. Druker:Bristol-Myers Squibb: PI or co-investigator on BMS clinical trials. OHSU and Dr. Druker have a financial interest in MolecularMD. OHSU has licensed technology used in some of these clinical trials to MolecularMD. Potential conflicts of interest are managed by OHSU. Other; Novartis: PI or co-investigator on Novartis clinical trials. OHSU and Dr. Druker have a financial interest in MolecularMD. OHSU has licensed technology used in some of these clinical trials to MolecularMD. Potential conflicts of interest are managed by OHSU., PI or co-investigator on Novartis clinical trials. OHSU and Dr. Druker have a financial interest in MolecularMD. OHSU has licensed technology used in some of these clinical trials to MolecularMD. Potential conflicts of interest are managed by OHSU. Other; Incyte: PI or co-investigator on clinical trials., PI or co-investigator on clinical trials. Other. Tyner:Incyte Corporation: Research Funding.


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