scholarly journals A Longitudinal Evaluation of Euroflow and Combined Quantitative Immunoprecipitation (QIP) and Free Light Chain (FLC) Mass Spectometry (MS) in Functional High Risk Multiple Myeloma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3090-3090
Author(s):  
Andrew Spencer ◽  
Tiffany Khong ◽  
Flora Yuen ◽  
Hannah Victoria Giles ◽  
Malgorzata Gorniak ◽  
...  

Introduction: The achievement of minimal residual disease (MRD) negativity is being increasingly recognised as the optimal measure of therapeutic response for both newly diagnosed and relapsed and/or refractory multiple myeloma (MM) patients. Bone marrow (BM) evaluation with either Next Generation Sequencing (NGS) or Next Generation Flow-cytometry (NGF) affords a high level of sensitivity and the attainment of MRD negativity (< 1 in 10-5 MM cells) with either approach is a powerful predictor of superior progression free survival (PFS). Both, however, are limited by the requirement for invasive bone marrow biopsy and the technical limitations imposed by variability in sample quality. Moreover, we and others have demonstrated the presence of significant spatial heterogeneity in MM that increases in the context of disease progression. Against this background we have evaluated a blood-based strategy for disease burden evaluation, Quantitative ImmunoPrecipitation (Mass Spectometry (QIP MS) and Free Light Chain Mass Spectometry (FLC MS) in a uniformly treated cohort of functional high-risk MM patients also undergoing sequential NGF (EuroFlow platform) MRD evaluation. Methods: Newly diagnosed MM patients failing (<partial remission [PR] as best response) front-line bortezomib-based induction therapy were enrolled onto the Australasian Leukaemia and Lymphoma Group (ALLG) MM17 trial (ACTRN12615000934549) evaluating an intensive salvage approach utilising a combination of carfilzomib, thalidomide and dexamethasone (KTd) as re-induction (KTd x 6 cycles) and as post autologous stem cell transplantation (ASCT) consolidation (KTd x 2 cycles followed by Td x10 cycles). NGF MRD status was determined pre-ASCT, post-ASCT and post-KTd consolidation utilising the standardised 8-colour EuroFlow platform. Matched serum samples from the 3 time-points were evaluated in parallel with QIP and FLC MS. Briefly, polyclonal antibodies (anti-IgG, -IgA, -IgM, -total κ, -total λ, free κ and free λ) covalently attached to paramagnetic microparticles were incubated with serum, washed and treated to simultaneously elute and reduce patient immunoglobulins. Light chain mass spectra were generated on a MALDI-TOF-MS system. Concordance between NGF and MS was assessed via the derivation of Cohen's kappa values. Results: Fifty patients were enrolled onto the ALLG MM17 trial. QIP and/or FLC MS identified the serum monoclonal paraprotein (PP) at baseline in all cases (100% sensitivity). Serum samples for MS with matched BM for NGF were available on 33 patients pre-ASCT, 32 post-ASCT and 26 post-KTd consolidation (91 matched samples in total). Sequential MS demonstrated serological complete remission (disappearance of MS baseline detectable monoclonal intact immunoglobulin [PP] and/or FLC) (CRMS) in 11%, 47% and 53% of patients pre-ASCT, post-ASCT and post-KTd, respectively. NGF MRD negativity at the same time points was 39%, 52% and 71% (the latter equivalent to a 50% MRD negativity rate within the original n=50 intention-to-treat population). The Cohen's kappa values for the 3 time-points were 0.21, 0.18 and 0.35 indicating fair to moderate concordance with the best concordance at the post-KTd consolidation time-point and with a Cohen's kappa value for the entire cohort (n=91) of 0.30. The sequential MS demonstrated that 12 patients had discordant disappearance of baseline PP and free light chains (FLC) prior to achieving CRMS. In 11 the FLC disappeared before the PP and in 1 the PP prior to the FLC. The former though to be due to either the FLC falling below the sensitivity of the technique following successful therapy or the presence of 2 sub-clones with differential drug sensitivity, whereas the latter was likely secondary to the persistence of a FLC expressing sub-clone. Post-KTd MS demonstrated good concordance with serological response (Cohen's kappa value = 0.61) but with 18% of patients demonstrating sCR/CR despite persisting MS detectable PP and/or FLC. Conclusion: These preliminary data confirm the utility of QIP MS and FLC MS for the sequential monitoring of tumour burden in HR MM. Concordance with standard monitoring was good with MS detectable disease in some patients with serological sCR/CR consistent with the higher sensitivity of MS. Concordance with NGF was only fair to moderate mandating the future comparison of larger sample sets to better understand the relationship between the 2 methodologies. Disclosures Spencer: Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; Secura Bio: Consultancy, Honoraria; Servier: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria; Specialised Therapeutics Australia: Consultancy, Honoraria. Khong:Novartis Oncology: Research Funding. Quach:Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Sanofi: Research Funding; GSK: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees. Kalff:Amgen: Honoraria; Celgene: Honoraria; pfizer: Honoraria. Reynolds:Novartis Australia: Honoraria; Alfred Health: Employment, Other: Biostatistician for trials funded by the Australian government and Abbvie, Amgen, Celgene, GSK, Janssen-Cilag, Merck, Novartis, Takeda, but sponsored by Alfred Health.; AUSTRALASIAN LEUKAEMIA & LYMPHOMA GROUP (ALLG): Consultancy; Novartis AG: Equity Ownership.

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4502-4502
Author(s):  
Angela Dispenzieri ◽  
Surendra Dasari ◽  
Bonnie Kaye Arendt ◽  
Mindy Kohlhagen Kohlhagen ◽  
Taxiarchis Kourelis ◽  
...  

Abstract INTRODUCTION: Our group has demonstrated that MASS-FIX is a quick, inexpensive, and accurate means to diagnose and monitor the serum and urine of patients with plasma cell disorders. Screening can be done with a MALDI-TOF MS and samples reflexed to microflow liquid chromatography coupled with electrospray ionization (ESI) and Q-TOF MS (microLC-ESI-Q-TOF MS). Because this technique provides a mass/charge (m/z) for a given patient's monoclonal protein, this method can provide greater sensitivity and specificity to monitor for complete response (CR), especially in patients receiving therapeutic monoclonal antibodies. Our goal was to assess the performance of miRAMM in patients with AL who have been classified as complete response using conventional means. METHODS: We identified 77 patients with AL who had both documented CR by immunofixation (Seibia) of the serum (SIFE), urine IFE (UIFE), and serum free light chain (FLC; The Binding Site) and paired serum samples to test by MALDI-TOF and ESI-TOF. No urine samples were available to test. Paired serum samples from baseline and approximately one year post-therapy were immunoaffinity purified using nanobodies targeting kappa, lambda, alpha, gamma and mu as previously described. For the MALDI-TOF (Bruker Microflex, LT), a range of 9,000 to 32,000 m/z was acquired. The m/z distribution was then visually inspected for the presence of a peak that was distinct from the polyclonal background in both the M+1 and M+2 light chain mass ranges. For the ESI-TOF, spectra were also collected on an TripleTOF 5600 quadrupole time-of-flight mass spectrometer (ABSciex, Vaughan ON, CA) in ESI positive mode with a Turbo V dual ion source with an automated calibrant delivery system. TOF MS scans were acquired from m/z 600−2500 with an acquisition time of 100 ms. RESULTS: Median age of the cohort was 58 (range 42, 81). Fifty-eight percent were male. No test was 100% sensitive at baseline with positive results as follows: abnormal FLC ratio, 82%; positive SIFE, 70%; 73% positive UIFE; positive serum MASS-FIX, 71%; and ESI-TOF, 79% . There was light chain isotype agreement in all cases, except for 2 patients for whom the SIFE and the FLCr disagreed. Of the 56 patients with baseline positive MASS-FIX, there was evidence of the original monoclonal protein in 5 patients (see figure for example of spectra illustrating same m/z before and after therapy). Of the 63 patients who had baseline positive ESI-TOF, there was evidence of the original monoclonal protein in 8 patients. Small unrelated monoclonal proteins were seen both by SIFE and by mass spectrometry techniques. With the spectrometry techniques, however, these transient oligoclonal bands could be distinguished from the original monoclonal protein when they shared the same isotype based on the difference in m/z. DISCUSSION: At baseline, the MALDI was able to identify the baseline monoclonal protein in a comparable number of patients as SIFE, UIFE, and FLC. Approximately 10% of patients thought to be in CR using routine screening tests were found to have persistence of their original clone by MALDI and by ESI-TOF. Small post-therapy unrelated monoclonal proteins were also seen both by IFE and by MALDI, but either the presence of a different isotype or in the case of MALDI, a different m/z, made it clear that the monoclonal protein was not related to the original clone. The sensitivity of the assay will improve significantly when we formalize the introduction of free light chain magnetic beads to capture the serum FLCs. Routine use of MASS-FIX of the urine will also increase performance characteristics. Figure. Figure. Disclosures Dispenzieri: Celgene, Takeda, Prothena, Jannsen, Pfizer, Alnylam, GSK: Research Funding. Gertz:Prothena: Honoraria; celgene: Consultancy; spectrum: Consultancy, Honoraria; Teva: Consultancy; Physicians Education Resource: Consultancy; annexon: Consultancy; Apellis: Consultancy; Alnylam: Honoraria; Medscape: Consultancy; Amgen: Consultancy; janssen: Consultancy; Research to Practice: Consultancy; Abbvie: Consultancy; Ionis: Honoraria. Kumar:Novartis: Research Funding; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding. Dingli:Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Millennium Takeda: Research Funding; Millennium Takeda: Research Funding. Kapoor:Takeda: Research Funding; Celgene: Research Funding. Russell:Vyriad: Equity Ownership.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1923-1923
Author(s):  
Jonathan J Keats ◽  
Esteban Braggio ◽  
Scott Van Wier ◽  
Patrick Blackburn ◽  
Angela Baker ◽  
...  

Abstract Abstract 1923 Our understanding of the genetic abnormalities associated with the development of multiple myeloma has increased significantly in the last decade. However, very little is known about how, or if, myeloma tumor genomes change with time and if therapeutic interventions influence these events. To address these issues we studied a cohort of 29 patients for whom at least two serial samples (1-65 months, median 19 months) were available for analysis. Each serial pair was analyzed by both array-based comparative genomic hybridization (aCGH) and microarray gene expression profiling (GEP) to identify DNA copy number abnormalities (CNA) at a 25kb resolution and gene expression differences present in the bulk of the tumor mass. Though this does not address the intra-clonal heterogeneity that may exist at a given time point, it does answer if the bulk of the tumor mass is changing with time. This study has unearthed several surprising and clinically relevant findings. First, myeloma tumor genomes are not as unstable as previous cytogenetic analyses suggest. In 40% of patients we observed no detectable CNA changes (1-37 months, median 12 months). In 24% of patients we observed the exclusive acquisition of new CNA (1-12, median 3.5) (3-22 months, median 18 months). In 36% of patients we observed both the loss (1-20, median 3) and gain (1-33, median 21) of CNA (5-43 months, median 20 months). Because time was not a significant influence on the detection of stable or unstable genomes we compared CNA changes with TC class and found patients with the high-risk 4p16 and maf IgH translocations were over-represented in the latter subset of patients. These observations raise the question of what happens between multiple rounds of therapy and if different regimens influence these phenotypes differently. For two patients with no CNA changes between the first two time points there was an additional sample that extended the follow-up by 52 and 12 months. Again no CNA changes were seen between diagnosis and these final samples taken 63 and 50 months later. For one patient with CNA changes (5 shared, 29 lost, and 32 gained) we have a detailed time course of 5 samples from diagnosis through to end-stage plasma cell leukemia. This patient received continuous lenalidomide-dexamethasone (Rd) for 20 months and progessed with a clone containing a BIRC2/3 deletion, which activates the NFKB pathway. The patient received single agent PR-171 and a bortezomib containing regimen and unexpectedly, the tumor genome observed in the third sample was almost identical (32 shared, 2 lost, and 4 gained CNA) to the first time point, including two copies of BIRC2/3. Subsequently, the patient received melphalan-prednisone-bortezomib (MPV) and the tumor genome observed in the fourth and fifth samples, which were identical, were similar to that seen in the second sample (24 shared, 13 lost, and 39 gained CNA). To understand these observations better we performed FISH to ascertain if the observed clones were detectable earlier, albeit at a low frequency. These experiments proved that the two dominant subclones observed at time points 1 and 3 versus 2, 4, 5 were mutually exclusive at the single cell level. Moreover, both of these clones were detectable at diagnosis with 12% of the tumor mass being the second subclone that eventually evolved into plasma cell leukemia. Interestingly, we assayed 5 of the 39 unique CNA observed in the final two samples and only one, the 17p13 deletion, was detectable earlier. This suggests the MPV regimen effectively eliminated a clone that was previously sensitive to Rd and selected for a dramatically evolved subclone that was previously sensitive to two different proteasome inhibitors. Although it is clear that the high-risk patients are enriched in the subset with the most changes, it is not clear if the specific drugs used (Melphalan vs IMID vs proteasome inhibitor) or intervention strategy (Cycled vs continuous/maintenance) and perhaps the response achieved (PR vs CR) influences these events. These observations do highlight two important clinical concepts that need to be considered in the future. First, the meaning of a partial response needs further investigation as this may reflect effective elimination of one subclone but not another. Second, because some patients are not changing or can revert back to a previous subclone we need to consider re-chanllenging patients with previously effective regimens when patients progress. Disclosures: Fonseca: Genzyme: Consultancy; Medtronic: Consultancy; BMS: Consultancy; AMGEN: Consultancy; Otsuka: Consultancy; Celgene: Consultancy, Research Funding; Intellikine: Consultancy; Cylene: Research Funding; Onyx: Research Funding; FISH probes prognostication in myeloma: Patents & Royalties. Stewart:Millennium: Consultancy; Celgene: Honoraria. Bergsagel:Amgen: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Genentech: Membership on an entity's Board of Directors or advisory committees; Millennium: Speakers Bureau; Novartis: Speakers Bureau.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3750-3750
Author(s):  
Jorge E. Cortes ◽  
Ricardo Pasquini ◽  
Hagop M. Kantarjian ◽  
David Joske ◽  
Luis A Meillon ◽  
...  

Abstract Abstract 3750 Background: The WORLD CML Registry is a multinational, prospective registry established to longitudinally assess global patterns of current and evolving methods for diagnosis, treatment, and clinical outcome measures in pts with CML and to compare clinical practice patterns to management recommendations provided by the European LeukemiaNet (ELN; Baccarani M, et al. J Clin Oncol. 2009;27:6041–6051). Here, we report overall efficacy and safety data from this registry, as well as clinical monitoring practices and outcomes in the subgroup of pts with CML in chronic phase (CP) treated with first-line imatinib. Methods: Pts (≥ 16 y of age) with CML in CP, accelerated phase (AP), or blast crisis (BC) within 6 mo + 2 weeks of confirmed CML diagnosis were enrolled at sites in Latin America, Asia-Pacific, the United States, Russia, Turkey, the Middle East, and Africa. Baseline demographics and medical history were collected at enrollment; disease status and management information were collected at approximate 6-mo intervals or when there was a change in disease status/management. Adverse events (AEs) were collected only if they resulted in a dose/regimen change, nonadherence to treatment, or death. Results: A total of 1837 of the 1889 pts enrolled between February 2008 and December 31, 2010, were evaluable (ie, had confirmed informed consent forms and no protocol deviations) and are the basis for this analysis. Median age was 47 y (range, 16–92 y), and 58% of pts were male. CML diagnosis was established using hematologic (91% of pts), bone marrow (82%), cytogenetic (83%), and molecular (polymerase chain reaction [PCR]; 53%) assessments. Nearly all pts (94%) were initially diagnosed in CP (Table). As of the data cutoff (December 31, 2010), median overall survival (OS) and median event-free survival (EFS) in all pts were not reached. Estimated OS and EFS rates at 3 y were 90.4% and 74.8%, respectively. AEs reported in ≥ 1% of pts were thrombocytopenia (3%) and neutropenia (2%). In the CML-CP subgroup, imatinib (Glivec®/Gleevec®) was administered as first-line therapy (in clinical practice or in a clinical trial) to 63% of pts (n = 1083). Disease burden in CML-CP pts on imatinib over time was most commonly assessed via blood counts (Table). Cytogenetic and molecular assessments were used in a minority of CML-CP pts at most time points. Only 50% of pts had a disease assessment at 3 mo (hematologic, 49%; cytogenetic, 10%; molecular, 15%). Of the pts on first-line imatinib outside of a clinical trial setting (n = 1024), 95 (9%) had their dose increased, 77 (8%) had their dose decreased, and 82 (8%) were switched to nilotinib or dasatinib. In all CML-CP pts treated with first-line imatinib, estimated OS and EFS rates at 3 y were 92.1% and 76.6%, respectively (Table). Estimated OS and EFS rates at 3 y were higher in pts who had higher imatinib exposure (treatment received ≥ 85% of total days) vs pts who received imatinib treatment on < 85% of days. Conclusions: The majority of CML-CP pts treated with first-line imatinib did not have cytogenetic or molecular assessments in accordance with current ELN recommendations, particularly at early time points. Additionally, pts who had higher drug exposure to imatinib had higher estimated OS and EFS rates at 3 y than those who did not. Disclosures: Cortes: Novartis: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Ariad: Consultancy, Research Funding. Kantarjian:Novartis Pharmaceuticals Corp: Consultancy, Research Funding; BMS: Research Funding; Pfizer: Research Funding. Piccolo:Novartis Pharma AG: Employment. Zernovak:Novartis Pharmaceuticals Corp: Employment, Equity Ownership. Sivarathinasami:Novartis Healthcare Pvt. Ltd,: Employment. Eng:Novartis Pharmaceuticals Corp: Employment, Equity Ownership. Kim:Novartis: Consultancy, Research Funding, Speakers Bureau; BMS: Consultancy, 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; ARIAD: Research Funding; II-Yang: Consultancy, Honoraria, Research Funding. Hughes:Novartis Pharmaceuticals Corp: Consultancy, Honoraria, Research Funding; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding; Ariad: Consultancy; CSL: Research Funding.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3150-3150 ◽  
Author(s):  
Raymond L. Comenzo ◽  
Daniel E Fein ◽  
Hani Hassoun ◽  
Christina Bello ◽  
Joanne F Chou ◽  
...  

Abstract Abstract 3150 Background: AL is a plasma cell dyscrasia characterized by the pathologic production of monoclonal light chains which misfold, deposit in various organs, including the heart, and can cause early death. High dose melphalan with stem cell transplant (SCT) results in high hematologic response rates and is a standard treatment for eligible patients. Achieving a complete hematologic response (CR) to SCT results in extended event-free and overall survival (OS), up to 8 and 13 years respectively in one large series. (Blood 2011; 118:4346) We have studied the addition of novel agents as consolidation following risk-adapted SCT (RA-SCT) in order to improve hematologic response (HR) rates and therefore outcomes. (Br J Haem 2007;139:224; Amyloid 2010;17:80a) In this report we examine the long-term outcomes of patients who received initial therapy with RA-SCT followed by consolidation for hematologic response less than CR (HR < CR). Methods: We performed a retrospective study to assess the HR rates, incidence of hematologic progression and overall survival (OS) of AL patients enrolled at diagnosis on two consecutive phase II trials using RA-SCT with consolidation for HR < CR (NCT01527032 and NCT00458822). OS was calculated from date of transplant to date of death or last follow up. Median event free survival (EFS) and OS were estimated by the method of Kaplan Meier. Cumulative incidence function was used to estimate the incidence of progression and death. Results: Between 2002 and 2011, 83 patients were enrolled and underwent RA-SCT on these trials and, following RA-SCT, those with HR < CR received consolidation with thalidomide and dexamethasone (TD) in the first and bortezomib and dexamethasone (BD) in the second trial. Thirty-six patients had cardiac involvement (43%) and all patients had free light chain measurements employed to score hematologic response and progression using consensus criteria (Am J Hematol 2005;79:319; Blood 2010;116:1364a). The frequency of CR following SCT was 24% and increased to 48% with post-SCT consolidation. The CR rates increased at 1 year compared to 3 months post-SCT from 21% to 36% with TD and from 28% to 62% with BD. With a median follow up of 5.1 years, the EFS is 4.5 years (95% CI: 2.6 to not reached) and the OS of all patients has not been reached (Figure 1). Sixteen patients died prior to hematologic progression and 26 patients have progressed with a cumulative incidence of hematologic progression of 8%, 18%, and 29% at 1, 2 and 3 years, respectively (Figure 2). Thirty-one percent (8/26) of relapsed patients have not required second-line therapy while among those who have, 78% (14/18) have responded including 44% (8/18) with CR. The median OS following hematologic progression was 5 years (95% CI: 2.6–5.8). Conclusions: Half of the AL patients on initial therapy trials employing RA-SCT and consolidation for HR < CR achieved CR with 36% of pts on the TD and 62% on the BD consolidation trial in CR at 1 year post-SCT respectively. At 3 years post-SCT the cumulative incidence of relapse was 29% and a third of relapsed patients did not require therapy, likely due to the very sensitive serum free light chain assay that detects low level hematologic progression in the absence of organ progression. Almost 80% of patients requiring second-line therapy responded, over half with CR, and median OS after relapse was 5 years. These results indicate that initial therapy with RA-SCT and consolidation is an effective initial treatment strategy for patients with AL in the era of novel agents. With over 5 years of follow up the median OS has not been reached. Disclosures: Comenzo: Millennium Pharmaceuticals, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Off Label Use: Use of the investigational agent MLN9708, an oral proteasome inhibitor, in the treatment of relapsed or refractory light-chain amyloidosis. Hassoun:Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Research Funding. Giralt:Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millenium: Membership on an entity's Board of Directors or advisory committees; Onyx: Membership on an entity's Board of Directors or advisory committees, Research Funding. Landau:Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Research Funding.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2270-2270
Author(s):  
Hiroaki Minami ◽  
Keiji Nogami ◽  
Midori Shima

Abstract Thrombin-catalyzed activation of factor (F)VIII by cleavages at Arg372, Arg740, and Arg1689 is essential for the propagation phase of blood coagulation cascade. Activated FVIII (FVIIIa) forms the tenase complex and markedly amplifies the activation of FX as a cofactor of FIX. We had already demonstrated that thrombin interacts with FVIII through the residues 392-394 and 484-509 in the A2 domain and the C2 domain, and each association regulates cleavage at Arg740, Arg372, and Arg1689, respectively (Nogami K, JBC 2000, 2005; BJH 2008), and recently reported that the A1 acidic clustered region 340-350 involving the sulfated tyrosine regulate the cleavage of Arg372 (Minami et al. 55th ASH). On the other hand, Fay and colleague suggested that recombinant FVIII lacking the C2 domain retains greater than 50% cofactor activity (JBC 2010), supporting the presence of other thrombin-binding region responsible for cleavage at Arg1689 of the light chain. In this study, we attempted to identify this thrombin-binding site(s). We focused on the acidic residues 1659-1669 and 1675-1685 within the light chain, which had similar sequence to the A1 residues 340-350 in terms of involving the clustered acidic residues and sulfated tyrosine as well as hirugen residues 54-65. We prepared four of synthetic peptides corresponding to the residues 1659-1669 and 1675-1685 with sulfated tyrosine, P(1659-69s) and P(1675-85s), and with non-sulfated tyrosine, P(1659-69) and P(1675-85). The inhibitory effect on the thrombin-catalyzed FVIII activation by each peptide was evaluated in a one-stage clotting assay. Each peptide showed a dose-dependent inhibition on thrombin-catalyzed activation. These inhibitory effects were greater in order of P1675-85s, P1659-69s, P1675-85, P1659-69, and the IC50 were 25, 67, 71 and 225 µM, respectively. The peptides with sulfated tyrosine had approximately 3-fold greater inhibition of the FVIII activation by thrombin than with non-sulfated tyrosine. The IC50 in the presence of mixture of P1675-85s and P1659-69s was 30.4 µM, suggesting that these peptides had no an additive effect. The impacts of P1659-69s and P1675-85s on the thrombin-catalyzed cleavage at Arg1689 were examined by SDS-PAGE/western blotting. These peptides blocked the cleavage at Arg1689 in dose-dependent fashions. In timed-course assay, the presence of P1659-69s and P1675-85s decreased the cleavage rate of Arg1689 by 61.3 % and 81.8 %, respectively compared to its absence. The direct binding of P1659-69s and P1675-85s to thrombin was examined by surface resonance plasmon (SPR)-based assay and by the zero-length cross-linking reagent EDC. In SPR-based assay using a Biacore T200TM, thrombin bound to immobilized P1659-69s and P1675-85s directly with high affinity. The Kd values adjusted to 1:1 binding model of global fitting were 203 nM and 94 nM, respectively. EDC cross-linking in fluid-phase assay revealed that formation of EDC cross-linking products between biotinylated P1659-69s or P1675-85s and thrombin were observed in dose-dependent fashions. The products between the biotinylated peptides (800 nM) and thrombin were competitively reduced by the addition of non-biotinylated peptides. Moreover, N-terminal sequence analysis of cross-linking products between both peptides-thrombin indicated that thrombin bound to the residues 1664-1669 and 1683-1684. Taken together, we demonstrated that the A3 residues 1659-1669 (QEEIDYDDTIS) and residues 1675-1685 (EDFDIYDEDEN) contained the thrombin binding-sites responsible for proteolytic cleavage at Arg1689 of the A3 domain. Disclosures Nogami: Bayer, NovoNordisk, Baxalta, Chugai, Kaketsuken, Pfizer, Biogen: Honoraria; Chugai: Membership on an entity's Board of Directors or advisory committees; Bayer, Novo Nordisk, Baxalta. Biogen: Research Funding. Shima:Chugai Pharmaceutical Co., Ltd. and F. Hoffmann-La Roche Ltd.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 227-227
Author(s):  
Silke Kapp-Schwoerer ◽  
Andrea Corbacioglu ◽  
Verena I. Gaidzik ◽  
Peter Paschka ◽  
Daniela Weber ◽  
...  

Abstract Background: Nucleophosmin (NPM1mut) mutations represent one of the most common gene mutations in acute myeloid leukaemia (AML) and can be used for monitoring minimal residual disease (MRD). In a former study, we could define clinical relevant check-points and a cut-off value to identify patients (pts) at high risk of relapse. Aims: To confirm our previous results on the clinical relevance of NPM1mut transcript levels (TL) in an extended cohort of younger AML pts (18 to 60 years) harbouring NPM1mut type A, B, C, D, JT, 4, QM, NM or KM, and to assess the impact of concurrent FLT3 internal tandem duplications (ITD) and DNMT3A (DNMT3Amut) mutations on NPM1mut TL kinetics. Methods: All pts were enrolled in one of four AMLSG [AMLHD98A (n=46; NCT00146120); AMLSG 07-04 (n=199; NCT00151242); AMLSG 09-09 (n=179; NCT00893399); AMLSG 16-10 (n=75; NCT01477606)] treatment trials. Treatment comprised double induction therapy (DI) with ICE (idarubicin, cytarabine, etoposide) with or without ATRA or gemtuzumab ozogamicin, or 1 cycle of daunorubicin and cytarabine followed by 1 to 4 cycles of high-dose cytarabine (n=292), autologous (n=19) or allogeneic stem cell transplantation (n=141). NPM1mut TL (ratio of NPM1mut/ABL1 transcripts x 104) were determined by RQ-PCR using TaqMan technology; the sensitivity of the assays was 10-5 to 10-6. DNMT3A and FLT3 -ITD (FLT3 -ITDmut) mutation status was assessed by standard PCR-based methods. Results: A total of 2835 samples from 499 NPM1mut pts were analysed at diagnosis (n=439), after each treatment cycle (n=1394) and during follow-up (FU) (n=1002). Peripheral blood (PB) samples were only included in the advanced FU period (defined as at least 12 months after completion of therapy). NPM1mut TL at diagnosis varied between 7.03 x103 and 2.38 x 107 (median 5.37 x 105). Pretreatment NPM1mut TL were not associated with clinical characteristics (e.g., age, WBC, BM blasts, FLT3 -ITDmut, DNMT3Amut) with the exception of LDH level (p=0.006) and did not impact event-free survival (EFS), relapse-free (RFS) and overall survival (OS). NPM1mut TL as log 10 transformed continuous variable at different time points during therapy were significantly associated with shorter remission duration (RD) and shorter OS. After DI therapy, the cumulative incidence of relapse (CIR) at 4 years was 10% for RQ-PCR-negative pts (n=41) versus 45% for RQ-PCR-positive pts (n=226) (p<0.0001); the lower CIR translated into a significant better OS (92% versus 60%, respectively; p=0.001). After completion of therapy, CIR at 4 years was 13% for RQ-PCR-negative pts (n=126) and thus significantly lower compared with 56% in RQ-PCR-positive pts (n=139; p<0.00001). Again, the lower CIR translated into a significantly better OS (81% versus 55%, respectively; p<0.00001). Multivariable analysis performed at both time points showed that NPM1mut TL were significantly associated with a shorter RD (HR, 1.86; 2.30, respectively) and shorter OS (HR, 1.58; 1.72, respectively). During FU, 1002 bone marrow (BM) and PB samples from 280 pts were analysed. The relapse rate at 2 years for pts exceeding the previously defined cut-off value of >200 NPM1mut copies was 90% with a median time to relapse of 1.38 months. In contrast, only 6/104 pts with sustaining RQ-PCR negativity relapsed. Finally, we evaluated the impact of concurrent FLT3 -ITDmut and DNMT3Amut on kinetics of NPM1mut TL. Following the first induction cycle, the median NPM1mut TL was significantly lower in pts with the NPM1mut/FLT3 -ITDwildtype/DNMT3Awildtype genotype compared to pts with the genotype NPM1mut/FLT3 -ITDmut/DNMT3Amut. This effect could be observed throughout subsequent treatment cycles. Conclusions: The results of our analysis on an extended cohort of younger AML pts with NPM1mut highly confirmed the two clinically relevant MRD check-points, after DI and after completion of therapy; during the FU period, exceeding a cut-off value of >200 TL was highly predictive for relapse. Finally, we found a significant impact of concurrent FLT3 -ITDmut/DNMT3Amut on the kinetics of NPM1mut TL. Disclosures Fielder: Amgen: Other: Congress Participation; Teva: Other: Congress Participation; Kolltan: Research Funding; Amgen: Research Funding; Pfizer: Research Funding; Astellas: Other: Congress Participation. Horst:Boehringer Ingleheim: Research Funding; MSD: Research Funding; Pfizer: Research Funding; Gilead: Honoraria, Research Funding; Amgen: Honoraria, Research Funding. Götze:Celgene Corp.: Honoraria; Novartis: Honoraria. Schlenk:Pfizer: Honoraria, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees; Teva: Honoraria, Research Funding; Boehringer-Ingelheim: Honoraria; Arog: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Daiichi Sankyo: Membership on an entity's Board of Directors or advisory committees.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2187-2187
Author(s):  
Surbhi Sidana ◽  
Nidhi Tandon ◽  
Angela Dispenzieri ◽  
Morie A. Gertz ◽  
Francis K Buadi ◽  
...  

Abstract Introduction: Melphalan based chemotherapy is commonly used for treatment of light chain amyloidosis (AL). Patients with AL often receive chemotherapy before autologous stem cell transplantation (ASCT) if they have high plasma cell burden or while awaiting ASCT. Melphalan is an alkylator and can affect bone marrow stem cells. Limited data is available on the effect of melphalan on stem cell mobilization in patients with amyloidosis. This study aims to identify the impact of melphalan therapy on collection of stem cells and ASCT in amyloidosis. Methods: All patients with AL seen at our institution within 90 days of diagnosis over a 10-year period (2006 to 2015) who underwent stem cell harvest were identified from an institutional database. Data pertaining to demographics, diagnosis, treatment, stem cell harvest and ASCT was extracted from the electronic medical records. Analysis was carried out by chi-square and Fisher's exact test for categorical variables and Kruskal-Wallis and Wilcoxon rank sum test for ordinal and continuous variables. Results: Three hundred and seventy two patients with AL who met the inclusion criteria were identified, of whom 10% (n=38) received melphalan based chemotherapy prior to harvesting, 28.5% (n=106) received non-melphalan based chemotherapy and 61.3% (n=228) received no chemotherapy prior to stem cell collection. Bortezomib based regimens were the most common (78%, n=83) non-melphalan based chemotherapy. All three groups were similar in terms of median age at diagnosis (59.1 years), median age at collection (59.4 years), gender distribution (59% males, n=221) and type of involved free light chain (FLC), with lambda being more common (72.2%, n=268). Patients who received melphalan-based chemotherapy had more cardiac (73.8% vs. 45.2% vs. 46.4%, p=0.005) and renal (84.2% vs. 50.9% vs. 68%, p=0.0002) involvement compared to other chemotherapy and no chemotherapy groups, respectively. In contrast, patients who received non-melphalan based chemotherapy had higher plasma cell burden (15% vs. 6% vs. 10%, p< 0.0001) and greater difference between involved and uninvolved FLC (44.2 mg/dL vs. 13.3 mg/dL vs. 13.2 mg/dL, p< 0.0001) compared to melphalan and no chemotherapy, respectively. Median duration of melphalan based chemotherapy was shorter at 54 days (34.5 to 79.5) or estimated 2 cycles compared to 101 days (60 to 135.5) or estimated 4 cycles (p=0.0019). Despite shorter duration of chemotherapy, total stem cell yield (million CD34/kg) was lower in patients who received melphalan based chemotherapy (5.54) compared to non-melphalan based chemotherapy (8.14) or no prior chemotherapy (7.94); p<0.0001. Similarly, day one stem cell yield (million CD34/kg) was the lowest in the melphalan group (2.71), followed by other chemotherapy group (3.63) and highest in no chemotherapy group (4.84); p<0.0001. This trend persisted for average stem cell yield per collection as illustrated in table 1. Filgrastrim (GCSF) alone was the most common mobilizing agent. However, patients with any chemotherapy prior to harvesting had higher utilization of plerixafor; 26.3% (n=10) in the melphalan group and 39.6% (n=42) in the non-melphalan group compared to 11.6% (n=27) if no prior chemotherapy (p<0.0001). However, no statistically significant difference was seen for melphalan vs. non-melphalan chemotherapy groups (p=0.44). In patients who underwent ASCT (85%, n=315), median stem cell dose (million CD34/kg) was different in the melphalan (3.66), non-melphalan (4.2) and no chemotherapy groups (4.44) (p=0.047), though the difference was not statistically significant amongst the 2 chemotherapy groups (p=0.34). There was also no difference in time to engraftment (table 1). Conclusions: Melphalan based chemotherapy, even if used for a short duration of time, significantly decreases both total stem cell yield and the yield on day one. It therefore has the potential to add to resource utilization with more collections needed. As much as possible, limited cycles of melphalan based chemotherapy or non-melphalan based treatment should be utilized in patients who are transplant eligible. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Alnylam: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees; Jannsen: Research Funding; Celgene: Research Funding; pfizer: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding. Kapoor:Amgen: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Kumar:Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Research Funding; Glycomimetics: Consultancy; BMS: Consultancy; Sanofi: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Millennium: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Kesios: Consultancy.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2082-2082
Author(s):  
Nidhi Tandon ◽  
Surbhi Sidana ◽  
Morie A. Gertz ◽  
Angela Dispenzieri ◽  
Martha Q. Lacy ◽  
...  

Abstract Introduction Immunoglobulin light chain amyloidosis (AL Amyloidosis) is a monoclonal plasma cell proliferative disorder that is characterized by tissue deposits of misfolded insoluble κ or λ light chain derived amyloid fibrils, leading to organ dysfunction. The prognosis of patients depends on the number and severity of organ involvement, especially cardiac involvement. Autologous stem cell transplant (ASCT), if eligible, alkylator (melphalan) and novel drugs like proteasome inhibitors (PI) and immunomodulators (IMiD) have improved the overall survival (OS) during the past decades. But still, nearly half of the patients die within a year of diagnosis. We analyzed the factors predicting early relapse / progression or death (within 12 months) after first line therapy for systemic AL amyloidosis. Methods Clinical and laboratory data of all consecutive patients with systemic AL amyloidosis seen at Mayo Clinic within 90 days of their diagnosis, between 2006 and 2015, was collected by chart review and analyzed retrospectively. Patients who died within 3 months of starting the first line treatment were excluded from analysis. Early relapse (ER) was defined as relapse / progression requiring treatment change / re-institution or death within 12 months of starting first line treatment. Patients in the cohort with ER were compared with patients with a follow up of more than 12 months who had a relapse / progression beyond 12 months or had continuing response at the time of analysis. Categorical variables were analyzed using chi - square and Fisher's exact test and continuous variables using Kruskal- Wallis test and Wilcoxon rank sum test. Multivariate analysis was done using logistic regression model. Results Seven hundred and eighty six patients with newly diagnosed systemic AL amyloidosis met the study criteria and were included in the analysis. Among these, 230 (29.3%) patients had ER within 12 months of starting initial therapy while 556 (70.7%) patients either relapsed after 1 year or had continuing response at the time of analysis. Baseline demographics, organ involvement and type of first line therapy are presented in Table1. The median estimated follow up for the entire cohort from start of initial therapy was 62.9 months (95% CI; 59.9, 67.3). The variables included in the univariate and multivariate analyses for factors predicting ER were age at diagnosis (≤ vs > 70 years ), revised mayo stage (I and II vs III and IV), bone marrow plasma cell percentage (BMPC; ≤ 10% vs > 10%), presence of any chromosomal abnormalities, trisomies or IgH translocations by fluorescence in situ hybridization (FISH), multiorgan involvement [(>1 vs 1) (heart, liver, kidney, gastrointestinal tract, autonomic neuropathy), incorporation of ASCT in initial therapy. In univariate analysis, mayo stage (p<0.0001), multiorgan involvement (p=0.0008) and inclusion of ASCT as part of initial therapy (p<0.0001) were significantly associated with ER, while age (p=0.06), BMPC(p=0.9), FISH abnormalities (p=0.2) were not. However, in multivariate analysis, only mayo stage (III + IV vs I + II; p=0.01) and non-inclusion of ASCT in first line treatment (p=0.0001) were significantly predictive of ER. Conclusions Despite the introduction of ASCT and novel drugs, the early mortality in systemic AL amyloidosis remains high. This study demonstrates that patients with ER are older with higher prevalence of cardiac involvement and multiorgan involvement and higher Mayo stage (III and IV). Incorporation of ASCT as part of the initial therapy was associated with reduced early relapse, but it is difficult to separate the influence of the eligibility for ASCT from the effect of ASCT itself. This will help us in characterizing these patients to better understand their mechanisms of resistance to therapy and gives an insight to the type of initial therapy that benefits them. Disclosures Dispenzieri: GSK: Membership on an entity's Board of Directors or advisory committees; Jannsen: Research Funding; Prothena: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam: Research Funding; pfizer: Research Funding. Kapoor:Takeda: Research Funding; Amgen: Research Funding; Celgene: Research Funding. Kumar:Celgene: Consultancy, Research Funding; Kesios: Consultancy; BMS: Consultancy; Sanofi: Consultancy, Research Funding; Noxxon Pharma: Consultancy, Research Funding; Glycomimetics: Consultancy; Millennium: Consultancy, Research Funding; Array BioPharma: Consultancy, Research Funding; Onyx: Consultancy, Research Funding; AbbVie: Research Funding; Skyline: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Research Funding.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 19-19
Author(s):  
Jo Howard ◽  
Kenneth I. Ataga ◽  
R. Clark Brown ◽  
Maureen Achebe ◽  
Videlis Nduba ◽  
...  

Background: Sickle cell disease (SCD) is a lifelong, inherited disorder characterized by mutations in the hemoglobin (Hb) subunit β gene that leads to the production of sickle hemoglobin (HbS). When HbS is deoxygenated, polymerization leads to red blood cell sickling and damage, resulting in hemolysis, chronic anemia, and episodic vaso-occlusive crises (VOCs). Patients with SCD are at an increased risk of developing long-term complications, including stroke, leg ulcers, and other end-organ damage. Lower Hb levels highly correlate with increased morbidity and early mortality in SCD. Voxelotor (Oxbryta®) is an oral, once-daily HbS polymerization inhibitor indicated for the treatment of SCD in adults and adolescent patients ≥12 years of age. The 24-week analysis of the HOPE trial demonstrated that treatment with voxelotor 1500 mg resulted in a significantly greater proportion of patients achieving a &gt;1 g/dL Hb increase compared with placebo (51.1% vs 6.5%, P&lt;0.001), which was associated with concordant improvements in hematological markers of hemolysis (indirect bilirubin and reticulocyte percentage). Here we report the evaluation of efficacy and safety of voxelotor 1500 mg at 72 weeks, the conclusion of the placebo-controlled HOPE trial. Methods: In the randomized, double-blinded, placebo-controlled, phase 3 HOPE trial, adults and adolescents (aged 12-65 years) with SCD were randomized to receive voxelotor (1500 mg or 900 mg) or placebo. Included patients had an Hb level of 5.5 to 10.5 g/dL at enrollment and 1 to 10 vaso-occlusive crises in the 12 months prior to screening. Concurrent hydroxyurea was allowed if the dose had been stable for ≥90 days at enrollment. Changes from baseline in Hb and hemolysis markers (absolute and percentage reticulocyte, indirect bilirubin levels, and lactate dehydrogenase levels) and safety were assessed at week 72. Results: 89% (95% CI, 82.4% to 95.4%) of patients receiving voxelotor 1500 mg achieved a Hb increase of &gt;1 g/dL at 1 or more time points during the 72-week treatment period compared with 25% (95% CI, 16.2% to 33.8%) of those receiving placebo (P&lt;0.001). The mean change in Hb from baseline at week 72 was 1.0 g/dL in patients treated with voxelotor 1500 mg compared with 0.0 g/dL in patients receiving placebo (Figure 1; P&lt;0.001). Mean change from baseline to average Hb throughout the 72-week duration was 1.26 g/dL in patients treated with voxelotor 1500 mg. Consistent with the week 24 analysis, significant improvements in markers of hemolysis (assessed by difference in adjusted mean percent change versus placebo) were seen in indirect bilirubin (-26.6% [95% CI, -40.2% to -12.9%]) and reticulocyte percentage (-18.6% [95% CI, -33.9% to -3.3%]) in the voxelotor 1500 mg group relative to placebo, with favorable trends of reduction in other markers, such as absolute reticulocyte count (-5.8% [95% CI, -23.4% to 11.9%] and lactate dehydrogenase (-4.8% [95% CI, -13.8% to 4.1%]). The overall incidence rate of VOCs was numerically lower in the 1500 mg arm compared with placebo, but was not statistically significant. Rates of non-SCD and SCD-related treatment-emergent adverse events were similar between the treatment groups, with no new safety signals noted through week 72. Conclusions: Voxelotor 1500 mg resulted in durable improvements in Hb levels and markers of hemolysis out to 72 weeks of treatment, with approximately 90% of patients achieving an increase in Hb &gt;1 g/dL at 1 or more time points during the study. Treatment with voxelotor remained well tolerated, with no new safety signals detected with longer-term follow-up. These results support the sustained and chronic use of voxelotor to reduce anemia and hemolysis, thereby potentially mitigating the associated morbidity and mortality of SCD. Disclosures Howard: Imara, Inc., Novartis, Resonance Health: Honoraria; Agios, Forma Therapeutics, Inc., Global Blood Therapeutics, Imara, Inc., Novo Nordisk, Novartis: Membership on an entity's Board of Directors or advisory committees. Ataga:Editas Medicine: Honoraria; Global Blood Therapeutics: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Shire/Takeda: Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Novo Nordisk: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Research Funding; Forma Therapeutics: Consultancy; Modus Therapeutics: Honoraria; Bioverativ: Honoraria, Membership on an entity's Board of Directors or advisory committees. Achebe:Global Blood Therapeutics: Consultancy. Hassab:Global Blood Therapeutics: Research Funding. Agodoa:Global Blood Therapeutics: Current Employment, Current equity holder in publicly-traded company. Tonda:Global Blood Therapeutics: Current Employment, Current equity holder in publicly-traded company. Gray:Global Blood Therapeutics: Current Employment, Current equity holder in publicly-traded company. Lehrer-Graiwer:Global Blood Therapeutics: Other: Former employee and former equity holder. Vichinsky:Pfizer: Research Funding; Agios: Research Funding; Global Blood Therapeutics: Consultancy.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2620-2620
Author(s):  
Shanmugapriya Thangavadivel ◽  
Alexander Pan ◽  
Xi Chen ◽  
Chen Song ◽  
Claire Snyder ◽  
...  

Abstract Introduction: The development of Bruton tyrosine kinase inhibitors (BTKi) and their introduction into clinical practice represent a major advance in the treatment of chronic lymphocytic leukemia (CLL). Ibrutinib and other second generation BTKi as monotherapies generally do not produce minimal residual disease negative (MRD-) complete remissions even with extended therapy. The reason for lack of continued elimination of CLL to a MRD- status over time is unknown, and we hypothesized that biological differences in the CLL cells or immune microenvironment might make them resistant to elimination. Methods: Samples were obtained from patients on continuous ibrutinib who hadn't relapsed at time points of 3 years on treatment and 5 years on treatment; and pre-ibrutinib. Isolated CLL cells were subject to B-cell receptor (BCR) sequencing using NEBNext Immune Sequencing Kit by New England Biolabs (NEB, Inc., USA). In a separate cohort, 10X VDJ+5'-sequencing was performed on peripheral blood mononuclear cells. Flow cytometry and ELISA were used to identify alterations in immune cell subtype and identify immune profiles associated with MRD positive (MRD+) status. Results: To identify the clonal pattern in MRD+, we performed deep sequencing of the BCR repertoire on samples from 13 patients with 3 time points each. We found that dominant clones tended to remain constant, but new clones appeared in later time points (Figure 1). MiXCR (v3.0.5) was used with default parameters to identify preprocessed reads containing CDR3 regions from B-cell heavy, kappa, and lambda chains, generating a list of unique productive and nonproductive CDR3 sequences associated with their relative abundances and specific V(D)J gene usage. Two out of three patients (patients 1 and 3) showed significant change in the clone over time. In patients 1 and 2, we saw that heavy chain clones emerge at later time points. In patient 3 alone, we observed that at 5 years there are two dominant clones. Our findings suggest that each patient shows a diverse repertoire of CLL clones and that the dominant clone does not change significantly across time points. To identify cell populations based on gene expression patterns, we performed 10X VDJ+5'-seq. Based on the expression of known markers, we identified CLL cells and other immune cell subtypes. We identified differentially expressed genes (DEGs) for CLL cells in each time points. Over time, we observed upregulation of CD79a, LTB, TAGLN2, and LGALS, genes typically associated with leukemic cell survival. Suggesting differential expression of pro-survival genes contribute to continued presence of MRD over time. T cells are known to be dysfunctional in CLL and have not previously been extensively studied in the setting of long term BTKi. We performed flow cytometry to determine the repertoire and function of T cells at 3 and 5 years of ibrutinib therapy. We found that the percentage of CD3+ T cells increases at later time points in all the 8 patients (p&lt;0.05). Although T cell numbers increase, we do see skewing of these cells towards a terminally differentiated phenotype (p&lt;0.05). We also observed significant increases in NK cells across time points (p&lt;0.05), albeit non-functional due to high expression of inhibitory receptor KLRG1 in 7 out of 8 patients (p&lt;0.05). Although overall the number of immune cells increase in long time ibrutinib therapy, they exhibit exhausted or non-functional phenotypes. Conclusion: Extended ibrutinib treatment yields a subset of patients who become MRD- whereas a large majority remain MRD+. Our findings suggest that BCR repertoire in CLL MRD might change in long term ibrutinib therapy and induce necessary genes for its survival in the microenvironment. Although T cells and NK cells are non-functional at later time points, better understanding of these subtypes may lead to new strategies and to improve antitumor function of these cells. Differentiating the biology of why certain patients attain MRD- status on BTK inhibitor is of high interest as it could provide rationale for therapy discontinuation or add on approaches. Figure 1 Figure 1. Disclosures Rogers: AbbVie Inc.: Consultancy, Research Funding; Acerta Pharma: Consultancy; AstraZeneca: Consultancy; Genentech: Consultancy, Research Funding; Innate Pharma: Consultancy; Pharmacyclics LLC: Consultancy; Janssen Pharmaceuticals, Inc: Research Funding; ovartis Pharmaceuticals Corporation: Research Funding. Bhat: Beigene: Consultancy; AstraZeneca: Consultancy; Aptitude Health: Honoraria; Onclive: Honoraria. Kittai: Bristol-Meyers Squibb: Consultancy; Abbvie: Consultancy; Janssen: Consultancy. Blachly: INNATE: Consultancy, Honoraria; KITE: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; AstraZeneca: Consultancy, Honoraria. Byrd: Novartis, Trillium, Astellas, AstraZeneca, Pharmacyclics, Syndax: Consultancy, Honoraria; Vincerx Pharmaceuticals: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Newave: Membership on an entity's Board of Directors or advisory committees. Woyach: AbbVie Inc, ArQule Inc, Janssen Biotech Inc, AstraZeneca, Beigene: Other: Advisory Committee; AbbVie Inc, ArQule Inc, AstraZeneca Pharmaceuticals LP, Janssen Biotech Inc, Pharmacyclics LLC, an AbbVie Company,: Consultancy; AbbVie Inc, Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company: Research Funding; Gilead Sciences Inc: Other: Data & Safety.


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