Citations 579

Prognostic Value of the Serum Free Light Chain Ratio in Patients with Newly Diagnosed Myeloma: Proposed Incorporation into the International Staging System.

Blood | October 10, 2019 | Volume: 110 | Issue: 11 | Pages: 659-659

10.1182/blood.v110.11.659.659

Abstract Background: The serum free light chain (FLC) ratio is a readily available laboratory test that has independent prognostic significance in monoclonal gammopathy of undetermined significance (MGUS) (Blood2005;106:812–17) and solitary plasmacytoma (Blood2006;108:1979–83). The purpose of this study was to determine if the FLC ratio will be of prognostic value in multiple myeloma (MM). Methods: We used a well characterized cohort of 1027 newly diagnosed MM patients seen at Mayo Clinic from January 1, 1985 to December 31, 1998 (Mayo Clin Proc2003;78:21–33) to ensure adequate follow up. Archived serum samples from blood drawn within 30 days of initial diagnosis were available on 790 of the 1027 patients. Quantitation of serum free κ and λ concentrations was performed on the archived sera by immunonephelometry, using specific antibodies on a BNII nephelometer. FLC ratio was calculated as κ /λ, i.e., free κ concentration divided by free λ, reference range 0.26–1.65. If the FLC ratio is >1.65, κ is considered to be the “involved” FLC and λ the “uninvolved” FLC, and vice versa if the ratio is less than 0.26. Incorporation of FLC into the International Staging System (ISS) was assessed in 576 of 790 patients (73%), in whom samples or data were available to estimate the ISS. Results: 790 patients (median age 66 years) were studied. The FLC ratio was outside the reference range in 95.1% of patients. The median involved κ and λ concentrations were 37.1 and 71.3 mg/dL, respectively. A cut-point κ /λ FLC ratio of <0.03 or >32 was chosen for further modeling analysis on the basis of its separation of the cohort into two roughly comparable parts. Overall survival was significantly inferior in patients with an FLC ratio <0.03 or >32 (n=479 patients) compared to those with an FLC ratio that was 0.03–32 (n=311 patients), with median survival of 30 versus 39 months, respectively, P<0.001 (hazard ratio 1.3, 95% CI 1.12–1.54). The FLC ratio (<0.03 or >32) retained independent significance after adjusting for the International Staging System (ISS) (P=0.03). The FLC ratio made the most significant contribution to predicting prognosis in patients with ISS Stage 2 (n=265 pts), separating this category of patients into those with 5 year survival rates of 20.5% (FLC ratio <0.03 or >32; n=152 pts) versus 35.2% (FLC ratio 0.03–32; n=113 pts), P=0.02. We studied the additional prognostic value of the serum FLC to the variables used in the ISS by defining FLC ratio <0.03 or >32, Sβ2M ≥3.5 g/L, and serum albumin <3.5 g/dL as three risk factors in a risk-stratification model. Patients with 0, 1, 2, or 3 risk factors had significantly different overall survival, with median overall survival times of 51, 39, 30 and 22 months, respectively, P<0.001. Conclusions: The serum FLC ratio at initial diagnosis is an important predictor of prognosis in myeloma. We show that the serum FLC ratio can be incorporated into the ISS, providing the greatest prognostic value in ISS Stage 2 patients, as well as providing a new risk-stratification model.
Lenalidomide Maintenance Therapy In Multiple Myeloma: A Meta-Analysis Of Randomized Trials

Blood | October 10, 2019 | Volume: 122 | Issue: 21 | Pages: 407-407

10.1182/blood.v122.21.407.407

Abstract Background Conflicting results have emerged, especially with respect to the impact on overall survival (OS), from trials evaluating lenalidomide maintenance (LM) therapy after induction therapy alone or post-autologous stem cell transplant (ASCT) in multiple myeloma (MM). We performed a systematic review and meta-analysis of existing outcome data from LM trials to evaluate role of lenalidomide as maintenance strategy in MM. Patients and methods A comprehensive search of electronic databases and abstracts through June 2013 was performed to identify randomized controlled trials (RCTs) that compared LM vs. placebo/no maintenance. Single arm studies were excluded. Pooled hazard ratio (HR) or odds ratio (OR) estimates with 95% confidence intervals (CIs) were calculated using the random-effects model for clinical endpoints of progression free survival (PFS), OS, response rate (RR) and adverse events (AEs), including second primary malignancies (SPMs). Analyses were performed using Comprehensive Meta-Analysis Software Version 2. We assessed between-study heterogeneity with the Cochran Q test and quantified its extent with the I2 statistic. Results Overall, five RCTs, with data extractable from four phase III trials (3 publications and 1 abstract) were identified (n= 1935). All studies were RCTs with an adequate randomization. MRC MM XI study was excluded from analyses as survival data are not available. Two placebo controlled trials (IFM 05-02, CALGB 100104) addressed the role of LM post-ASCT, one placebo-controlled trial (MM-015) studied LM therapy in the non-transplant setting and the remaining trial (RV-MM-PI209) had a 2 X 2 design comprising of both ASCT and non-transplant randomized arms followed by a second randomization of LM versus no maintenance. There was no heterogeneity for estimate of PFS results (Cochran Q, p=0.68; I2=0%), but considerable heterogeneity for estimate of OS (Cochran Q, p=0.09; I2= 55%), among the studies. There was significant prolongation of both PFS (HR 0.49, 95% CI, 0.41–0.58, p<0.001) and OS (HR 0.77, 95% CI, 0.62–0.95, p=0.013) with LM vs. placebo/no maintenance (Figure 1). Best response during maintenance was reported only in 2 studies and odds of responding (very good partial response or better) were not significantly different with LM (OR 1.28, p=0.3). Grade 3-4 AEs data were available from 3 trials for calculation of pooled OR with LM compared with placebo. We observed a nearly two-fold increase in the risk of SPMs with LM (OR 1.99; 95% CI, 1.31–3.04; p=0.001). Patients on LM were more likely to have grade 3-4 AEs than placebo: neutropenia (OR 4.9, p<0.001), thrombocytopenia (OR 2.7, p<0.001), fatigue (OR 2.3, p=0.01) and venous thromboembolism (OR 3.2, p=0.02). Odds of discontinuing treatment were also significantly higher in patients on lenalidomide (OR 2.9, p<0.001). Conclusions Meta-analysis of RCTs demonstrates significant improvement in PFS and modest improvement in OS with LM. There is an increased risk of grade 3-4 adverse effects, including SPMs with LM. Substantial heterogeneity for estimate of OS among protocols is a limitation of this analysis. Lack of uniform access to lenalidomide upon disease progression in the placebo/no maintenance arms of the constituent studies should be taken into account while interpreting aggregate effect estimates for OS in this meta-analysis. OS: Cochran Q p=0.09, I2=55%, substantial heterogeneity PFS: Cochran Q p=0.68, I2=0%, minimal heterogeneity Disclosures: Off Label Use: Lenalidomide for maintenance therapy in multiple myeloma. Kumar:Merck: Consultancy, Honoraria; Celgene: Consultancy, Research Funding; Millennium: The Takeda Oncology Company: Research Funding; Novartis: Research Funding; Genzyme: Research Funding. Dispenzieri:Celgene, Millenium, Jansenn, Pfizer: Research Funding. Bergsagel:Onyx: Consultancy. Lacy:Celgene Corporation: Research Funding.
Acquired in Vitro Resistance to Ibrutinib Is Associated with Transcriptional Re-Programming and Sustained Survival Signaling in Waldenströms Macroglobulinemia and Mantle Cell Lymphoma, Independent of BTK Cys481 Mutation

Blood | October 10, 2019 | Volume: 124 | Issue: 21 | Pages: 2250-2250

10.1182/blood.v124.21.2250.2250

Abstract Background: While B-cell receptor (BCR) signaling is essential for the development, of normal B cells, its aberrant hyper-activation results in neoplastic transformation of B-lymphocytes. Recent investigations using small molecule inhibitors validate the BCR pathway as a valuable target. Bruton’s tyrosine kinase (BTK) is one of the components of a signaling hub that transduces signals from the BCR into the cell for its activation and has been shown to be a therapeutic target. Ibrutinib (PCI-32765), an irreversible BTK inhibitor has shown clinical efficacy in CLL, mantle cell lymphoma (MCL) and Waldenströms macroglobulinemia (WM). Ibrutinib binds to cysteine-481 of the BTK protein and blocks its phosphorylation, resulting in termination of BCR-mediated activation of cells with a concomitant induction of death. Despite the clinical success of ibrutinib, a high percentage of patients achieve only partial response and eventually acquire resistance to the drug, resulting in aggressive relapse of the disease. A mutation of Cys481-Ser in BTK (ibrutinib-BTK binding site) has been reported to be one of the reasons for the development of ibrutinib resistance (IR). To understand the mechanisms resulting in acquisition of IR, we developed preclinical models of IR in WM and MCL. Materials: Ibrutinib was obtained from Pharmacyclics, CA. Validated human WM models (BCWM.1, RPCI-WM1 and MWCL.1 cell lines) and human MCL models (Jeko-1 and Maver cell lines) were used for the study. Results: BTK was constitutively phosphorylated at Y223 and Y551 in all the cell lines tested and this was inhibited by ibrutinib in a dose dependent manner. Phosphorylation of other kinases in the cascade such as SYK (Y323 and Y525/526) and PLCg2 (Y759 and Y1217) were also inhibited while AKT phosphorylation at both Ser473 and Thr308 was consistently increased in presence of ibrutinib. Treatment with ibrutinib induced cell cycle arrest in the G1 phase by 24h followed by apoptosis. Cell growth assays (MTS assay) showed that BCWM.1 was the most sensitive cell line followed by MWCL-1, RPCI-WM1, Maver and Jeko-1. Exposure of WM and MCL cells for prolonged periods of time with progressively increasing concentrations of ibrutinib resulted in outgrowth of clones (IR WM and MCL cell lines) that were resistant to apoptosis with a slow growth rate as compared to wild type parental cells. IR cells attained 2 – 20 fold resistance to ibrutinib as compared to the respective parental lines as determined by MTS assay. Sequence analysis of the BTK gene in all the cell lines revealed no mutation in IR cells at Cys481 suggesting that in an acquired IR state, resistance to ibrutinib can be developed independent of BTK Cys481 mutation. Interestingly, we found p-BTK levels to be markedly reduced in IR cells. Ibrutinib reversal experiments suggested that while a continuous presence of ibrutinib is needed for inhibition of BTK phosphorylation, a stable IR state could be maintained (for >1 month) in the absence of ibrutinib. This suggested the cells reliance on a parallel survival pathway, independent of BTK phosphorylation. Focused mRNA (Nanostring nCounter assay) and immunoblot analysis revealed significant changes in the expression profiles of several cellular elements. These included transcription factors such as PU.1, IRF4, BLIMP1, BCL-6 b-catenin as well as the phosphorylated ERK1/2, STAT1 and 3 suggesting a reprogramming of critical cellular networks, which IR tumor cells might be utilizing to overcome ibrutinib-induced cytotoxicity. Importantly, we observed that IR cells retained high levels of p-AKT and showed an increase in expression of BCL2 family members, as well as BCL-2 itself. Treatment of IR cells with ibrutinib +/- MK2206 (AKT inhibitor), or ABT-199 (BCL-2 inhibitor), synergistically induced cytotoxicity in IR cells, suggesting the importance of these parallel survival pathways (AKT/BCL2) in maintaining an IR state. Conclusion: Here we demonstrate that in the absence of BTK Cys481 mutation, an IR state is associated with reprogramming of transcriptional networks countering ibrutinib-induced toxicity by activation of AKT and BCL-2. Our current data exposes multiple vulnerabilities within IR cells, which can be therapeutically exploited to potentially delay onset of IR, by targeting alternative oncogenic mechanisms that are activated in presence of sustained BTK inhibition. Disclosures No relevant conflicts of interest to declare.
The Mayo Clinic Experience with 66 Patients with Type II Cryoglobulinemia.

Blood | October 10, 2019 | Volume: 104 | Issue: 11 | Pages: 1493-1493

10.1182/blood.v104.11.1493.1493

Abstract Background: Cryoglobulinemia(CG) is a relatively uncommon disorder which has been recognized as a syndrome for nearly forty years. The further classification into types I, II, and III was established thirty years ago, with Type II consisting of a monoclonal immunoglobulin possessing activity towards a polyclonal component. In the interim, many disease associations have been described and various therapies tried, but clinical trials remain rare, and the natural history, causes, and pathways of CG require further investigation. Methods: We examined the records of all patients seen at the Mayo Clinic, Rochester, with Type II CG between 3/2/1994 and 11/27/2000 using a prospectively held dysproteinemia database. Results: Of 66 total patients 30 were male(45%) and 36 were female(55%) with mean ages of 52.7±11.0 and 60.9±12.6, respectively. 63 patients were Caucasian, with one each of African, Hispanic, and other. 34 patients(52%) presented with purpura, 16 with edema(24%), 12 with neuropathy(18%), 12 with fatigue, 10 with arthralgia(15%), 8 with weight loss(12%), 5 with livido reticularis(8%), 4 with leg ulcers(6%), and 2 with infarcted extremities(2%). Of our patients, 13 had Type II CG (20%) unassociated with infection or lymphoma. 38 patients(58%) had hepatitis C(HCV), of whom 12 underwent genotyping with 10 having genotype 1a or 1b and 2 having genotype 2a or 2b. No patients had isolated Hepatitis B(HBV) though 8 HCV patients were coinfected with HBV. One patient each had CMV and EBV. 7 patients(10%) had Sjogren’s disease, and 1 had scleroderma. 11 patients (17%) had a lymphoproliferative disorder (LPD), and 5 more went on to develop LPD. Of these, 7 patients had a B-cell LPD, 4 had a MALT lymphoma, 4 had a non specific LPD, one had a lymphoplasmacytic lymphoma, and one had Gaucher’s thrombocytopenia. Significant renal disease developed in 23 patients(35%), with 12 being membranoproliferative glomerulonephritis (18%) and 3 being mesangioproliferative glomerulonephritis. Pertinent laboratory finding included a mean cryocrit of 7.6%±12.5, a positive rheumatoid factor in 36 out of 36, and hypocomplementemia in 33 of 41(80%). Liver function testing was reflective of the patient’s hepatitis status. Serum electrophoresis in 48 patients revealed the following patterns: 22 were normal(46%), 15 had a γ peak(31%), 5 polyclonal patterns(10%), 5 hypogammaglobulinemia, and one a β-γ peak. Of 32 samples where a monoclonal antibody was isolated 29 were IgM (91%), and 3 IgG (9%). The light chains were 88% κ, with 12% λ. Treatment was generally guided by the comorbidities, and many (30%) required no specific treatment for Type II CG. In the 38 HCV patients, 17 received interferon with or without ribavirin and 18 were deemed not to need treatment, while 2 received steroids alone and 1 was lost to follow up. In 28 patients without HCV 20 received steroids(71%), while 5 received other treatments and 3 were untreated. Of 46 patients who received any treatment, 27 (59%) achieved no response or had disease progression and required a change in therapy. To date, 8 patients have died, with none of deaths specifically attributable to complications of cryoglobulinemia. Conclusion: Type II CG is a non fatal disease most frequently associated with HCV. Optimal disease specific treatment is as yet undefined, and is generally directed at the underlying comorbidity when possible. Not all cases require treatment and many can be followed symptomatically.
AL Amyloidosis and Patient Reported Quality of Life

Blood | October 10, 2019 | Volume: 126 | Issue: 23 | Pages: 3317-3317

10.1182/blood.v126.23.3317.3317

Abstract Background: Patients with light chain amyloidosis (AL) often have delayed diagnosis and present with significant symptomatology; this may result in decreased quality of life (QOL). With improving treatment options providing longer survival, it is increasingly important to assess QOL. However there is paucity of data in the literature addressing QOL in AL patients. We prospectively employ a "Hematology Patient Reported Symptom Screen" (HPRSS) which consists of three questions about fatigue, pain and overall QOL. The aim of this study is to understand if HPRSS parameters predict various clinical outcomes. Methods: Eligibility for this retrospective study was as follows: 1) New diagnosis of AL between 2009-2014; 2) baseline HPRSS documented in the medical record; and 3) at least a year of follow-up, which included either death within or follow-up through 12 months after diagnosis. The HPRSS questions were rated on a 1-10 scale, with 10 being the worst for fatigue and pain, and 10 being the best for overall QOL. Scores were abstracted from visits at time of diagnosis, and at 12 months +/- 1 month post-diagnosis. We considered a 2-point difference in serial scores a "change" over time. Results: For the 302 patients in this study, the baseline median scores [interquartile range] for fatigue, pain, and QOL were 6 [3,7], 2 [0,5] and 5 [3,8], respectively. Median overall survival (OS) was 39.1 months, with 102 deaths in the first year. There were significant differences in baseline HPRSS between those who lived longer than one year and the early death patients in the domains of fatigue (5 [IQR 3, 7] vs. 7 [IQR 5, 8], p<0.0001) and QOL (6 [IQR 4, 8] vs. 5 [IQR 3, 7], p=0.006), but not in pain (2 [IQR 0, 5] vs. 2 [IQR 0, 5]). There were significant baseline differences in the early death group for alkaline phosphatase, bilirubin, creatinine, and Mayo stage. Patients who received ASCT had the best baseline fatigue 4 [2.5,6] and QOL 7 [5,8] scores and were significantly different from those who did not receive ASCT [fatigue p<0.0001) and QOL (p<0.0001)] On univariate analysis fatigue and QOL were prognostic for OS. On multivariate analysis Mayo 2012 staging, autologous stem cell transplant and baseline fatigue remained independently prognostic. When analyses were restricted to the 125 patients with HPRSS measurements at 12 months, we found that over time QOL scores improved significantly 6 [IQR 3.5, 8] to 7 [IQR 5, 8] (two sided Wilcoxon signed rank p=0.01), but fatigue (5 [IQR 2, 5] to 4.5 [IQR 3, 6]) and pain scores (2 [IQR 0 ,4] to 1.5 [IQR 0, 4]) did not. Patients with worse baseline parameters tended to have improvement in QOL by 12 months while those with the best baseline parameters tended to decline in QOL although not statistically significant. When we included the 102 patients who died within 12 months to the comparison, the early death patients had the worst baseline parameters and there were significant differences across all 4 groups for most characteristics (Table 1). There was no association between achieving hematologic or organ response with change in QOL. Conclusion: Asking patients with AL to rate their fatigue and QOL using a 10-point scale has predictive value. Patient reported fatigue at diagnosis is an independent prognostic factor for survival. Survival at one year was associated with significant improvement in QOL. Table 1. Baseline parameters between patients with early death and/or survive 12 months. Grouped by Patient Reported QOL at 12 months Relative to Baseline Dead by 12 months, n=102 Improved, n=44 Stable, n=55 Worsened, n=26 pa HPRSS scores [IQR] Baseline QOL Baseline fatigue Baseline pain 12 month QOL 12 month fatigue 12 month pain 5 [3,7] 7 [5,8] 2 [0,5] NA NA NA 4 [3-5] b,c,d6 [4-8] b,c2 [0-4] 7 [6-9] b,d4 [1.25-6] 1 [0-3] 7 [4-8] 4 [2-7] 2 [1-5] 7 [4-8] 5 [3-6] 2 [0-4] 8 [7-10] 2.5 [0-5.25] 2 [0-6.25] 5 [3-7] 5 [3-6] 2.5 [1-4] <0.0001 <0.0001 NS NS 0.001 NS dFLC, mg/dL 48 (2.89-726) 30 (1.1-494) 19 (36-455) 22 (0.2-2097) 0.008 Troponin, ng/mL 0.065 (<0.01-0.84) 0.02 (<0.01-1.6) 0.01 (<0.01-0.19) 0.01 (<0.01-0.14) <0.0001 NT-proBNP pg/mL 5222 (159-70,000) 1766 (26-16868) 1381 (24-19180) 496 (56-2973) <0.0001 Received Transplant (%) 4 (4) 13 (33) 36 (50) 13 (50) 0.0002 a Significant by Wilcoxon across all 4 categories; b Significant difference between Improved and Worsened; c Significant difference between Improved and Stable; d Significant difference between Worsened and Stable Disclosures Kumar: Millenium: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Abbvie: Research Funding; Janssen: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Novartis: Research Funding; Onyx: Consultancy, Research Funding. Thompson:Kite Pharma: Research Funding.
Impact of Novel Agents on Young Patients with t(11;14) Multiple Myeloma

Blood | October 10, 2019 | Volume: 124 | Issue: 21 | Pages: 2059-2059

10.1182/blood.v124.21.2059.2059

Abstract Background: Outcome studies for the unique cohort of young patients with multiple myeloma (MM) are sparse. In general, MM is a heterogenous disease with the genetic signature being one of the major determinants of prognosis. We have recently reported on improvement in overall survival (OS) of young patients with the use of novel agents, but the maximal survival gain has been achieved by integrating autologous stem cell transplant (SCT) to our current approach. Herein, we report on outcomes of patients with MM who were 50 years or younger at diagnosis and stratified by fluorescence in situ hybridization (FISH) results. Our study focuses on t(11;14) myeloma as its prognostic impact remains unclear with the use of novel agents upfront. Methods: Out of 1384 patients with MM, evaluated consecutively at Mayo Clinic, Rochester, MN between 1/1/2000 and 12/31/2011, 290 (21%) were 50 years or younger at diagnosis. Interphase FISH, performed within 100 days of diagnosis of MM, was utilized to stratify patients as high-risk [deletion 17p, t(14;16), t(14;20) or t(4;14)] or standard-risk [normal FISH, trisomies, t(11;14), t(6;14) or monosomy13/deletion 13q]. FISH results were available in 125 young patients that comprise the cohort of interest in the current study. OS from diagnosis was estimated by the Kaplan-Meier method. Results: Median age at diagnosis of MM was 47 years (range: 22 to 50 years) and 58% of the patients were male. At the time of data cut-off (7/31/2014), 45 (36%) patients had died with 90% of all known causes of deaths (n=39) being MM related. FISH abnormalities were noted in 114 (91%) patients. At diagnosis, 46%, 30% and 24% patients were categorized as International Staging System (ISS) stage I, II and III, respectively. The estimated median follow up was 60 months (95% CI: 54-67) and the 5-year OS rate was 69% [median 86 months (95% CI: 76-108)]. Standard (n=100; 80%) and high (n=25; 20%) risk patients had a median OS of 89 months (95% CI: 76-108) and 77.6 months (95% CI: 42-130), respectively (p=0.87). In order to further investigate the similar outcomes between these broad risk-groups with typically diverse disease course, we assessed the outcomes based on the common genetic abnormalities (Table 1) within each of the 2 categories. Presence of t(11;14) (n=37; 29%) was associated with a significantly shorter median OS (76 months) compared to patients with trisomic and normal FISH profile (n=46) (91 months, p=0.01; Figure 1). Patients with t(11;14) also had a significantly shorter median OS compared to those with other standard-risk FISH abnormalities (median OS 96 months, p=0.02). Presence of t(11;14) was not associated with higher plasma cell labeling index (PCLI, p=0.29) or worse ISS stage (p=0.99) compared to patients without t(11;14). OS survival of patients with t(11;14) was similar to those with high risk features (median 76.2 vs. 77.6 months, p=0.32). Of 24 (65%) patients with t(11;14) who underwent SCT, 79% had early SCT (within 12 months from diagnosis). Median OS was 79.4 months (95% CI: 36-108) vs. not reached (NR) (95% CI: 27-NR), respectively (p=0.79) in early versus late SCT. Twenty-one (57%) and 13 (35%) patients with t(11;14) received initial immunomodulatory drugs or bortezomib-based therapies, respectively. Those receiving frontline bortezomib had a higher median OS (76.2 months, 95% CI 76-79) compared to 64.8 months (95% CI 32-108) with other initial agents although it did not reach statistical significance (p=0.78). Conclusion: Presence of t(11;14) is associated with an inferior OS compared to patients with normal FISH, trisomies, or other standard risk abnormalities in young patients with MM. Given, the inherent biases associated with a retrospective study from a referral institution, our findings require external validation. However, our data suggest that our current therapeutic approaches in managing young patients with this unique genetic signature are inadequate. Table 1FISHn(%)Median OS in months (95% CI)t(11;14)37(29)76.2 (53.5-107.7)Trisomies35(28)91.3 (76.4-NR)13/del(13q)11(9)NR (32-NR)Normal11(9)95.5 (45.4-95.6)t(4;14)11(9)NR (40.1-NR)del(17p)/-1710(8)42 (19.2-129.6)t(14;16)4(3)77.6 (42.4-NR)Others6(5)NR (11.5-NR) Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.
Associations of DNA Repair Gene Polymorphisms in XRCC1 and ERCC2 with Clinical Outcome in ECOG Trial E9486.

Blood | October 10, 2019 | Volume: 104 | Issue: 11 | Pages: 1475-1475

10.1182/blood.v104.11.1475.1475

Abstract Although multiple myeloma is clinically defined as the accumulation of clonal, malignant plasma cells in the bone marrow, the disease shows significant heterogeneity with regard to morphology, progression and therapeutic response. Our hypothesis is that this heterogeneity likely is due, in part, to germline genetic polymorphisms that contribute significantly to an individual’s disease course and response. In particular, individuals deficient in the repair of DNA damage are not only at high risk for developing cancer, but also could show DNA repair dependent responses associated with DNA damaging therapeutic agents. In this study we examined the association of functional genetic polymorphisms in the DNA repair genes, XRCC1 (SNP positions 280, 399) and ERCC2 (SNP positions 312, 751), with toxicities and clinical outcomes in the ECOG, 3 arm chemotherapeutic trial, E9486 [A-VBMCP, B-VBMCP+Cylophosphamide, C- VBMCP+interferon]. DNA from 359 patients was genotyped and examined for association with response, toxicities, blood counts, bone pathology, and survival parameters. Notably, in the interferon arm of the trial significant associations were observed in progression free survival and polymorphisms of XRCC399 (AA median survival 51 months versus AG/GG median survival of 33 months; p=,008), ERCC751 (AA/AC median survival 33 months versus CC median survival of 48 months; p=.05), and ERCC312 (AA median survival 49 months versus AG/GG median survival of 34 months; p=.02). Hazard ratios ranged form 1.7 to 2.05 for survival differences associated with DNA repair genes in this arm. Interestingly, T cell counts are known to be impacted by interferon; and DNA repair polymorphisms in this arm were also associated with CD8+ T cell counts. While this represents a single arm of one clinical trial, it is intriguing to consider the impact of genetic polymorphisms on DNA repair in light of chemotherapeutic agents that may affect cells of the immune system. Previous studies from the ECOG Myeloma Committee of the E9486 trial show highly significant associations of survival and immune status in myeloma patients. Our results suggest genetic polymorphisms in DNA repair genes may influence clinical outcome in certain therapeutic regimens. Genetic polymorphisms in these DNA repair genes are currently being completed in 800 patients of the SW9321 SWOG/ECOG intergroup trial and additional association studies will be included in the presentation.
N-Terminal Fragment of the Type-B Natriuretic Peptide (NT-proBNP) Is a Prognostic Factor for Overall Survival in Newly Diagnosed Patients with Multiple Myeloma (MM)

Blood | October 10, 2019 | Volume: 126 | Issue: 23 | Pages: 3292-3292

10.1182/blood.v126.23.3292.3292

Abstract Background: Both MM specific and patient specific parameters place patients at risk for death. Patient frailty has been delineated primarily by age and ECOG performance score (PS) and secondarily with creatinine, eGFR, and the International Staging System (ISS), which reflect both renal function and disease burden. In an attempt to improve upon these commonly used measures, a frailty score for elderly patients that combines functional status [Activity of Daily Living (ADL) and Instrumental Activity of Daily living scores], comorbidities [Charlson comorbidity index (CCI)] and age has been developed by the IMWG. Incorporation of these tools into a busy clinical practice is challenging due to time constraints. Therefore, the identification of frail patients with an easily applicable, rapid and objective tool remains a challenge and an unmet need. A reliable, non-invasively assessable, biochemical marker of frailty would be an ideal tool to identify patients at higher risk of death. It was our goal to determine the role of NT-proBNP, a well-established cardiovascular risk biomarker, as a marker of frailty in patients with MM and in predicting overall survival (OS). Methods: Patients were elegible for this retrospective study if they were seen at the Mayo Clinic, Rochester, MN within 30 days of their myeloma diagnosis during the interval between 1/1/2007 and 12/31/2011. As part of the Mayo Clinic registration, all patients complete forms containing their past medical history, symptoms, and ADLs. Data from that first visit was abstracted and used to calculate a CCI. We excluded all patients with a concomitant diagnosis of light-chain AL amyloidosis. NT-proBNP concentration was measured in frozen sera collected within 30 days of diagnosis. NT-proBNP assay was run on the E170 Modular analyzer (Roche Diagnostics, Penzberg, Germany). We evaluated the prognostic role of NT-proBNP and these indices on OS using the Kaplan-Meier method. Results: Among the 351 consecutive patients satisfying entry criteria, median age was 65 years (range 22-95), 33% were ≥70 years, and 56% were male. Twenty-eight percent were ISS stage III, 13% had a creatinine ≥2 mg/dL, 19% had PS ≥2, and 11% had ADL score ≥2, and 30% CCI ≥2. The median value of NT-proBNP was 109 ng/L (interquartile range: 30-375 ng/L). NT-proBNP concentrations differed in the three ISS stages (median: 122 ng/L stage I, 190 ng/L stage II and 1822 ng/L stage III, P<0.0001). Median OS was 5.6 years. The best cutoff of NT-proBNP predicting OS at one year was 301 ng/L (sensitivity: 57.88%, specificity: 74.29%; AUC=0.668) and distinguished two groups with different OS (median not reached vs. 35 months, P<0.0001). Variables predictive for OS are shown in the Table and included PS, age, CCI, ISS, NT-proBNP. On multivariate analysis, ISS and NT-proBNP were independent of each other as long as age, PS and/or CCI were excluded from the model. NT-proBNP withstood these clinical variables better than did ISS (data not shown). We built two different models (table). In model 1, NT-proBNP >301 ng/L was an independent predictor of survival while age ≥70 and PS ≥2 and CCI were not significant. However, if we considered ISS stage instead of NT-proBNP in the same model, ISS stage was not significant. Conclusions: In this unselected cohort of patients with newly diagnosed multiple myeloma, NT-proBNP was a useful predictor of survival independent of age and PS. The threshold of 301 ng/L is remarkably similar to the well-established cutoff for heart failure of 300 ng/L. NT-proBNP outperformed the CCI and the ISS as risk factors. NT-proBNP is a widely available biomarker that could be added to the panel of laboratory tests of newly diagnosed MM patients and serve as a simple means of determining patient frailty in a busy clinical practice. Table. Results of univariate and multivariate analysis of various prognostic factors (NS, not significant; NI, not included). Univariate Multivariate Multivariate RR (95% CI) P Model 1 P Model 2 P PS ≥2 3.4 (2.4-4.8) <0.0001 2.5 (1.7-3.6) <0.0001 2.8 (1.9-4.0) <0.0001 Age ≥70 2.7 (1.9-3.6) <0.0001 2.1 (1.5-2.9) <0.0001 1.9 (1.3-2.7) 0.0003 CCI >=2 1.9 (1.4-2.6) <0.0001 NS NS 1.5 (1.0-2.0) 0.03 ISS stage 1.1 (1.1-1.8) 0.0004 NI NI NS NS NT-proBNP >301 ng/L 2.3 (1.7-3.2) <0.0001 1.6 (1.1-2.2) 0.007 NI NI Disclosures Merlini: Janssen-Cilag: Honoraria; Prothena: Honoraria; Millennium-Takeda: Honoraria; Pfizer: Honoraria. Kumar:Janssen: Research Funding; Celgene: Research Funding; Sanofi: Research Funding; Millenium/Takeda: Research Funding; AbbVie: Research Funding; Onyx: Research Funding; Celgene, Millenium, Sanofi, Skyline, BMS, Onyx, Noxxon,: Other: Consultant, no compensation,; Skyline, Noxxon: Honoraria.
Circulating Blood B Cells in Multiple Myeloma: Analysis and Relationship to Circulating Clonal Cells and Clinical Parameters in a Cohort of Patients Entered on the Eastern Cooperative Oncology Group Phase III E9486 Clinical Trial

Blood | October 10, 2019 | Volume: 90 | Issue: 1 | Pages: 340-345

10.1182/blood.v90.1.340

AbstractRecent analyses of circulating blood B cells in myeloma have generated controversy concerning the exact levels of these cells and whether they may represent circulating clonal tumor B cells. Previous reports suggested that CD19+ B cells are markedly increased in myeloma patients and that this population shares clonotypic rearrangements with the malignant plasma cell. We studied the numbers of CD19+ B cells by flow cytometry in previously untreated newly diagnosed myeloma patients in Eastern Cooperative Oncology Group (ECOG) phase III trial E9486. There were 628 patients who were eligible for the clinical protocol E9486, but of these 521 were also entered on the companion laboratory study (E9487) and had CD19 data. In comparison with normal controls, the myeloma patients exhibited a marked heterogeneity in the number of circulating CD19+ B cells as detected by flow cytometry. Approximately 20% of patients had significantly increased levels of circulating CD19+ B cells. However, the total CD19+ blood population from myeloma was not significantly different from the median of age-matched, normal controls. Analysis of CD19+ blood cells in relationship to circulating clonal cells was done in 13 myeloma patients using a clonotypic, quantitative allele-specific oligonucleotide-polymerase chain reaction (PCR) assay. No correlation was found between the numbers of CD19+ B cells (range, 5% to 51%) and PCR estimates of the number of clonal cells in the peripheral blood (range, .009% to 3.6%). Low CD19+ B-cell level (&lt;125 μL) was associated with clinical stage III (P = .033). A significant relationship exists between higher levels (≥125/μL) of CD19 cells and longer overall survival (P &lt; .0001). In addition, high CD19 levels also predicted a clinical response and longer event-free survival. There was a strong inverse association between the level of CD19 values at diagnosis and infections within the first 2 months of diagnosis. Importantly, the number of deaths related to infections was significantly greater in the low versus high CD19 group (P &lt; .0202). Also, CD19 is an independent prognostic factor in addition to plasma cell labeling indices, β2 -microglobulin, hemoglobin, and plasmablastic morphology. Patients with infections were more likely to have low levels of CD19+ cells. In summary, higher CD19+ cell levels are a favorable prognostic sign with no apparent relationship to circulating tumor cells. In addition, this analysis strongly suggests that low peripheral blood levels of CD19+ cells are an adverse prognostic sign in myeloma. The CD19+ cell levels in myeloma patients is an important parameter in the overall assessment of these patients.
The Selective Bcl-2 Inhibitor ABT-199 Synergizes with BTK or Proteasome Inhibitors to Induce Potent Cell Death in Preclinical Models of Bortezomib or Ibrutinib-Resistant Waldenströms Macroglobulinemia

Blood | October 10, 2019 | Volume: 124 | Issue: 21 | Pages: 1689-1689

10.1182/blood.v124.21.1689.1689

Abstract Background:The pathological behavior of Waldenströms macroglobulinemia (WM) cells relies on aberrant B-cell receptor (BCR), and Toll-like receptor (TLR) signaling and is intricately supported by malfunctions in initiation of apoptosis. In this dynamic, a complex shift between functionally active pro-apoptotic and anti-apoptotic proteins from the Bcl-2 family occurs and bestows the malignant cells with a significant survival advantage. This defective apoptotic signaling is associated with aggressive clinical behavior, chemoresistance, and a poor prognosis in many B-cell cancers, including WM. Thus, BCR/TLR induced proliferation and abnormal apoptotic signaling due to dysregulation of Bcl-2 signaling, act in concert for the assurance of the malignant WM cells survival. Clinically, mitigation of BCR signaling with the first in class BTK inhibitor, ibrutinib, has shown promising results in WM and other B-cell cancers. However, clinical responses to the BTK inhibitor alone are less than optimal and development of ibrutinib-resistant disease is being recognized as an important and impending dilemma. We have previously shown the utility of disrupting pro-apoptotic Bcl-2 protein interactions in WM, chronic lymphocytic leukemia and multiple myeloma and that this functional interference results in re-sensitization (or heightened sensitivity) of tumor cells towards chemoimmunotherapy. As such, we examined the effects of ABT-199, a Bcl-2 specific small molecule inhibitor, in preclinical models of WM. Importantly; we conducted this investigation in proprietarily developed WM cells that have acquired resistance mechanisms towards either ibrutinib (IR WM subclones) or bortezomib (BR WM subclones). Materials:WM cell lines (BCWM.1, MWCL.1 and RPCI-WM1; WT cells) including their bortezomib resistant (BR) or ibrutinib resistant (IR) subclones were used in this study. Results: An initial comparison of Bcl-2 family members, Bcl-2, Mcl-1, BCL-xL, A1 (anti-apoptotic members), Noxa, Puma, Bim (pro-apoptotic initiators) and Bak and Bax (pro-apoptotic effectors), revealed that BR WM cells express increased levels of pro-apoptotic Bcl-2 family members, particularly Bcl-2, relative to WT cells. Similarly, A1 and Bcl-2 levels were up regulated in IR cell lines suggesting that the Bcl-2 mediated survival pathway is involved in resistance to both bortezomib and ibrutinib. Cell growth (MTS) assays using ABT-199 indicated that both BR and IR cells were equally sensitivity to Bcl-2 inhibition, with an IC50 ranging between 2 – 4mM. ABT-199 induced a dose dependent increase in MOMP with concomitant induction of apoptotic cell death, the latter confirmed by observation of PARP-1 cleavage. ABT-199 induced an intrinsic apoptotic program with the activation of caspase 9 and caspase 3 in all the cells tested. This data indicated the Bcl-2 pathway as being relevant and essential in WM cell lines even under drug resistant conditions. To evaluate the priming effect of ABT-199 on bortezomib and ibrutinib induced cell death, MTS assays were performed with these drugs in presence of IC25 concentrations of ABT-199. The addition of ABT-199 significantly reduced the IC50of both bortezomib and ibrutinib in WT, BR and IR cells. This suggested that re-sensitization of BR and IR cells towards either bortezomib or ibrutinib, respectively, was possible in presence of ABT-199. Further, combined addition of ABT-199 with bortezomib or ibrutinib showed synergistic cell death (combination index range: 0.004 – 0.6, CalcuSyn, Biosoft UK) in BR or IR WM cells, respectively. Conclusion: Dysregulation of Bcl-2 signaling is associated with the pathogenesis and promotion of drug resistance in B-cell cancers, including WM. Our report is first to highlight in WM preclinically, the antiproliferative effect of disrupting Bcl-2, through use of ABT-199. Altogether, our data suggests that therapeutic interference of Bcl-2 function with ABT-199 complements the anti-WM activity of ibrutinib or bortezomib in a synergistic manner and can in fact restore sensitivity of either drug in WM cells that are resistant to proteasome or BTK inhibitors. Focused mRNA and protein profiling analyses are currently underway to delineate the mechanisms accounting for synergy observed between concomitant Bcl-2/BTK inhibition as well Bcl-2/proteasome inhibition. Disclosures Ansell: Biothera: Research Funding. Martin:Janssen: Honoraria. Coleman:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millennium: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx: Speakers Bureau.