Lust, John A.

Abstract Abstract 1988 Background With the utilization of novel agent-based combination therapies and autologous stem-cell transplantation (ASCT) in multiple myeloma (MM), the rigorous response category of stringent complete remission (sCR) in the international uniform response criteria is increasingly becoming attainable. In addition to the standard criteria for complete remission (CR), sCR requires normalization of the free light chain ratio and disappearance of clonal cells as determined by the marrow immunofluorescence or immunohistochemistry. We have previously validated the new response category of sCR created in by the International Myeloma Working Group and demonstrated that sCR represents a deeper level of response, translating into a superior OS. Herein we report the survival outcomes of patients attaining sCR or standard CR, from a 2-year landmark after ASCT in a cohort of patients with extended follow-up. Additionally, we report the outcome of patients who remained in sCR for at least 6 months (sustained-sCR) after ASCT. Patients and Methods Maximal response rates of four hundred and forty-five consecutive patients who underwent ASCT within 12 months of diagnosis of MM were determined. The population achieving varying degrees of complete remission (n=237) is the focus of this study. We performed a landmark analysis 2 years after ASCT to ensure that all the patients attaining at least CR had sufficient time to reach the response levels being studied. Patients were categorized as having sustained sCR (sus-sCR) if the duration of sCR was at least 6 months. Overall survival (OS) was estimated by the Kaplan Meier method and the survival curves were compared by log-rank test. Results The median follow-up of the entire cohort was seventy-seven months (95% CI: 73–82 months). The sCR rate after ASCT was 24% (n=109). Median time to progression (TTP) of patients attaining sCR was 50 months from ASCT, and median overall survival (OS) is not reached, in contrast to those attaining standard CR (n=37, TTP=20 months, OS=81 months) or near CR/nCR (n=91; TTP= 19 months, OS=60 months, p<0.0001 for both TTP and OS). OS of patients surviving at least 2 years from ASCT (Figure 1a) continued to remain superior for those attaining sCR (n=105, median: not reached) versus 70 months for the CR group (n=32; p=0.004). Among patients achieving sCR (n=109), OS of patients with sus-sCR (n= 75) at 6 months from ASCT is not reached (5-year OS=91%, 7-year OS=86%) versus median OS of 66 months (5-year OS=49%, 7-year OS=37%; p<0.0001) for those who had non-sustained-sCR (n=34) after ASCT (Figure 1b). Conclusion In our landmark analysis of patients with MM who survived at least 2 years from ASCT, those attaining sCR have a markedly superior outcome compared to those attaining standard CR. However, among patients attaining sCR, those with sustained sCR of 6 months or greater had the best outcome. Myeloma trials reporting response rates should identify patients achieving sCR and CR separately owing to markedly disparate outcomes of the two categories. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 1831 Poster Board I-857 IL-1 Antagonists Are More Effective at Inhibiting IL-6 Production than Apoptosis Inducing Agents: Implications for Targeting the Myeloma Proliferative Component. John A. Lust, MD,PhD1, Steven R. Zeldenrust, MD, PhD1, Laurie L. Moon-Tasson1*, and Kathleen A. Donovan, PhD1*. 1Division of Hematology, Mayo Clinic, Rochester, MN, United States, 55905. Background Multiple myeloma patients with an elevated growth rate have a shortened duration of response and survival. IL-6 is a central myeloma growth factor and we have shown that abnormal production of IL-1beta in the myeloma microenvironment stimulates the generation of paracrine IL-6 and myeloma cell growth in vivo. Dexamethasone and IL-1Ra both have the ability to inhibit IL-1 induced IL-6 production in vitro however their ability to inhibit IL-6 production and myeloma cell growth have not been investigated in a comparative fashion. Methods In vitro, IL-1 (100, 10, 1 pg/ml) was added to stromal cell cultures in the presence or absence of IL-1Ra (1 and 0.1 μg/ml) or dexamethasone (100 and 10 μM). IL-6 levels were quantitated by ELISA. In vivo, a patient with smoldering myeloma (≥ 10% bone marrow plasma cells) received 100 mg of IL-1Ra SQ qd for 6 months, low dose dexamethasone (20 mg qweek) for 6 months, followed by the combination of IL-1Ra and dexamethasone for 6 months. The bone marrow plasma cell percentage (BMPC), serum IgG, the plasma cell labeling index (marker of myeloma cell proliferation) and the C-reactive protein (marker of IL-6 production) were monitored serially. Results The effects of IL-1Ra and dexamethasone on IL-1 induced IL-6 production by marrow stromal cells are detailed in Figure 1. The results showed that IL-1Ra at 1 μg/ml was able to inhibit IL-1 induced IL-6 production back to baseline at all IL-1 concentrations tested. The inhibitory effect was less pronounced at 0.1 μg/ml IL-1Ra but still superior to dexamethasone. Dexamethasone was less effective at IL-6 inhibition compared to IL-1Ra using 100 and 10 pg/ml of IL-1 but similar at 1 pg/ml of IL-1. Of interest, the patient treated with IL-1Ra alone, dexamethasone alone, and the combination appeared to mimic these results in vivo. Anakinra alone induced a reduction of the PCLI and CRP. Dexamethasone alone decreased the M-protein; however the PCLI and CRP values increased. The PCLI increased from 0% to 0.8% and the CRP increased from 0.18 up to 1.48 indicating increased levels of IL-6 and a more active proliferative component of the disease. Subsequently, the combination of dexamethasone and IL-1Ra led to a further decrease in the IgG and the PCLI and CRP decreased again; PCLI decreased from 0.8% to 0.2% and CRP decreased from 1.48 down to 0.40. Conclusion The above results suggest that agents such as IL-1Ra are more effective at IL-6 inhibition and targeting the proliferative myeloma component than apoptosis inducing agents such as dexamethasone. Combination therapy with IL-1 inhibitors and apoptosis inducing agents may be useful in patients with active myeloma that have an elevated PCLI at diagnosis. Disclosures No relevant conflicts of interest to declare.

Summary Improvement in survival in Light chain (AL) amyloidosis has been seen over recent decades, enabling more patients to achieve long‐term survival. Patients with AL amyloidosis who survived ≥10 years from time of diagnosis ( n = 186) were the subject of this study. Ten‐year survivors represented 22% of the total population. These patients were characterized by favourable patient, organ and plasma cell features. Of note, trisomies were less common among 10‐year survivors compared to those who did not survive to 10 years. All‐time best haematological response was complete response in 67%, very good partial response in 30%, partial response in 2% and no response in 1%, with 11% having received a consolidative strategy for inadequate response to first line therapy. The overall organ response rate to first‐line therapy was 76%, which increased to 86% when considering subsequent line(s) of therapy. Forty‐seven percent of the 10‐year survivors did not require a second‐line therapy. The median treatment‐free survival (TFS) among the 10‐year survivors was 10·5 years (interquartile range 7·4‐12·2). On multivariate analysis independent predictors for TFS were the achievement of complete haematological response and lack of cardiac involvement. Long‐term survivors are increasingly seen in AL amyloidosis and present distinct patient, organ and clonal disease features.

Abstract The high-risk abnormality del(17p) can be detected by fluorescence in situ hybridization on malignant plasma cells (PCs) and has an adverse prognostic impact in patients with multiple myeloma (MM). Patients with del(17p) have reduced overall survival (OS). Patients who acquire del(17p) later during the disease course are not well described. The disease characteristics at diagnosis predicting for acquired del(17p) and its overall impact on patient survival is not known. We compared 76 patients with MM who were negative for del(17p) at diagnosis and acquired it later with 152 control MM patients who did not acquire del(17p) at a comparable time point. Patients acquired del(17p) at a median of 35.6 months (range, 4.6-116.1 months) from diagnosis of MM after a median of 2 lines of therapy (range, 1-10 lines of therapy). When compared with controls, patients with acquired del(17p) had shorter median progression-free survival (PFS) (30.1 vs 23.0 months; P = .032) and OS (106.1 vs 68.2 months; P &lt; .001) from diagnosis. After the detection of del(17p), the median PFS was 5.4 months and the median OS was 18.1 months. High lactate dehydrogenase level (odds ratio [OR], 3.69; 95% confidence interval [CI], 1.11-12.24) and presence of t(4;14) (OR, 2.66; 95% CI, 1.09-6.48) or any high-risk translocation (OR, 2.23; 95% CI, 1.00-4.95) at diagnosis predicted acquisition of del(17p). High PC proliferative rate predicted shorter OS from detection of del(17p) (hazard ratio, 2.28; 95% CI, 1.31-3.96; P = .004). Our study shows that acquisition of del(17p) is an important molecular event associated with reduction in OS in MM. Certain baseline factors may predict acquisition of del(17p). This needs validation in prospective data sets.