Lacy, Martha Q.

8011 Background: Literature suggests that three or more organ involvement is a contraindication for autologous stem cell transplant (ASCT) in light chain amyloidosis (AL). Most centers limit transplantation to patients who have no more than two organs significantly involved. Methods: We retrospectively reviewed all patients with AL Amyloidosis involving three or more organs and who had ASCT between 1996-2015 at Mayo clinic, Rochester, Minnesota. Results: Seventy five patients underwent ASCT with three or more organs involved. Median age at diagnosis was 54 years and 67% were males. The heart was involved in 95%, followed by kidneys (84%). Thirty eight patients (51%) had no induction treatment prior to ASCT. Full dose melphalan (200mg/m2) was given in 45%, and the remaining received a reduced dose (140mg/m2). Overall response rate (hematological) was 75%. The median progression-free (PFS) and overall survival (OS) were 16.3 and 68.9 months, respectively. The 100-day mortality was 16% and overall forty four patients (59%) died during the follow up period. The most common causes of death were cardiovascular events (32%) and progressive amyloidosis (25%). On multivariable analysis, predictors for PFS were Mayo stage III/IV (RR 3.3, P = 0.0012) and hematological response (≥VGPR, RR 0.4, P = 0.012). An NT-ProBNP level of ≥2000 pg/ml was an independent predictor for shorter PFS (RR 2.6, P = 0.013). Predictors for OS included any hematological response (RR 0.1, P < 0.0001) and Mayo stage III/IV (RR 7, P < 0.0001). When looking at the NT-ProBNP, a level ≥2000 was prognostic (RR 5.5, P = 0.001). Number of organs involved (3 vs. 4-5) was not significant in either PFS or OS. Conclusions: We conclude that the high prevalence of cardiac involvement is the main driver for the poor outcome in patients who have three or more organs involved. Using selection criteria defined for safe transplantation in cardiac amyloidosis should result in low therapy-related mortality independent of the number of organs involved. The concept of considering patients with three organs involved ineligible for stem cell transplantation should be abandoned.

7559 Background: Waldenström macroglobulinemia (WM) is a rare indolent lymphoma commonly treated with rituximab (R)-based therapy. The use of rituximab maintenance (mR) in WM is controversial. We present a case-control study of patients (pts) with WM treated with mR. Methods: Pts evaluated at Mayo Clinic, Rochester with active WM that received mR between 1/2000 & 6/2018 were included. Cases comprised pts who received mR following R-based induction as primary therapy. Cases were matched based on the time of diagnosis in 1:2 ratio with a control group treated with R-based primary induction therapy without mR. Time to event analyses were performed from initiation of R-based induction. Results: Of 776 pts with active WM, 42 (5%) cases received mR and 84 pts were selected as controls. The median follow-up and the proportion of high risk pts were comparable between the two cohorts (Table). Pts in the mR cohort show a trend toward longer time to next therapy (TTNT) and a significantly longer overall survival (OS) compared to the control group (Table). The R-based induction therapies were comparable in the two cohorts (p = 0.6). Median duration of mR was 1.9 yrs (95% CI 1.6-2) and mR was used most frequently every (q) 2 (range 1-6) months. Of the 42 mR pts, 25 (60%) received an R-based combination for induction and 17 (40%) received R monotherapy as induction. Five (12%) pts discontinued mR due to toxicity, infections were reported in 13 pts (31%) during mR therapy and 3 pts (7%) received IVIg infusions for recurrent infections. Conclusions: R-based induction followed by mR demonstrates a longer OS in WM compared to R-treated control population not receiving mR, albeit at a high rate of infections. Despite limitations of a retrospective study, with a heterogeneously treated cohort, these data add to the body of literature supporting Rituximab maintenance. Results from an ongoing randomized controlled trial are awaited. [Table: see text]

7509 Background: Waldenstrom macroglobulinemia (WM) is a rare lymphoma for which scant comparative data exist to guide frontline therapy. Herein, we compare 3 commonly used regimens in WM: R-Benda, DRC, and BDR in frontline setting. Methods: Patients (Pts) with active WM seen at Mayo Clinic between 2000 & 2018 who received R-Benda, DRC or BDR as primary therapy were included in this retrospective study. Response rates were assessed by Consensus Criteria. All time to event analyses were performed from the frontline therapy, using Kaplan-Meier method. Results: The study included 172 pts with active WM (R-Benda, n=67, DRC, n=75, BDR, n=30).The median follow-up for the entire cohort was 3.7 years (y) (95% CI 3.7-3.0). Baseline characteristics, including IPSS, and time to frontline therapy from WM diagnosis were similar across the 3 cohorts. Clinically relevant endpoints are shown in the Table. Hematologic and non-hematologic toxicities were similar across the 3 groups. Grade 3 neuropathy requiring treatment discontinuation was encountered in 13% pts treated with BDR. 56 pts received subsequent salvage therapy [(10% in R-Benda arm, 44% in DRC arm, & 53% in BDR arm]; 29% pts in the R-Benda arm and 30% pts in DRC arm received a PI-based regimen while 69% pts in the BDR arm received alkylator-rituximab based therapy. Conclusions: Outcomes (MRR, TTNT and EFS) with frontline R-Benda are superior in comparison to frontline DRC or BDR in patients with WM. Clinically relevant endpoints are not significantly different with DRC vs. BDR. The toxicity profile across the 3 groups was comparable. [Table: see text]

8606 Background: The rapidity of response to initial therapy in multiple myeloma (MM) depends on a variety of factors. There is limited data on its implications on long term outcomes in patients (pts) with newly diagnosed MM. Methods: We retrospectively examined the outcomes in a cohort of 454 pts with newly diagnosed MM between Jan 2000- Dec 2011 undergoing induction therapy. Results: The median age at diagnosis was 66 yrs (29-92). Pts had measurable serum M-spike (>= 1 g/dL), dFLC (>=10 mg/dl) or 24 hour urinary M protein excretion (UrM; >=200 mg) in 70, 63 and 39% respectively. We first examined the relationship between the response to first cycle of therapy and overall survival (OS). We divided pts into quartiles based on their % reduction in the serum M spike, dFLC or UrM. The median OS (Table) was poorest for pts with the least reduction of serum M protein (P<0.001) and of dFLC. The cutoffs for Q1 was 25, 40and 40% decrease for serum M spike, dFLC and 24 hr UrM respectively. Among various baseline characteristics only higher age was predictive of a poor (Q1) response. Given the trend toward worse OS among the Q 4 group (maximum decrease in serum M spike), we examined the relationship to cytogenetic risk. Among 232 pts with FISH data available, proportion of pts with high-risk disease was 27, 12, 22 and 31% respectively in quartiles 1 - 4). In a multivariate analysis, quartile 1 and 4 of serum M-protein response and the high-risk FISH were independent risk factors associated inferior OS. Conclusions: Both shallow and very deep response to therapy in cycle 1 is a strong indicator of eventual disease outcome and should be considered as marker of high-risk disease, likely through different mechanisms. For the shallow responders, prospective trials should assess if a change in therapeutic management will alter the outcome of these pts. The rapid deep responders also appear represent a different high-risk biology, emphasizing the fact that pts with high-risk disease often have excellent initial responses, but poor long term outcomes. [Table: see text]

8600 Background: The combination of bortezomib, dexamethasone, thalidomide, cisplatin, doxorubicin, cyclophosphamide and etoposide (VDTPACE) was developed as an intense regimen for disease control prior to tandem transplantation for multiple myeloma (MM) in total therapy protocols. The regimen is very effective in this setting, and since has also been used in the relapsed setting. We examined the outcomes of a set of patients undergoing VDTPACE therapy for relapsed MM at our institution. Methods: We identified 71 patients who received VDTPACE for relapsed MM, at Mayo Clinic from 7/2006 to 7/2012. Plasma cell leukemia was excluded. All data was extracted from clinical records. Results: The median age of patients was 59 years (range, 39-80); 48 (67.6%) were male. The median time from diagnosis to initiation of VDTPACE was 38.2 months (range, 2-125). The median number of cycles given was 1 (range, 1-9). The overall response rate after one cycle was 57.1% (14.3% VGPR, 22.2% PR and 20.6% MR) in the 63 patients in whom the response was evaluable. The median overall survival (OS) post-VDTPACE was 8.2 months (95% CI, 5.7-10.9). Eighteen (25.4%) patients went on to autologous stem cell transplantation (SCT), and 7 (9.9%) received matched allogeneic SCT following VDTPACE, and the median OS post-VDTPACE was significantly longer for these groups compared to those who were not transplanted (15.3 and 20.5 months, respectively vs 5 months, p-value <0.001). Thirty eight of 66 (57.6%) patients were rehospitalized after initial admission for infusion therapy for a median duration of 6 days (range, 1-26). The median platelet and red cell transfusions were 4 (range, 0-21) and 5 (range, 0-22) units, respectively. Renal toxicity was seen in 13/62 (21%) patients and 27/65 (41.5%) patients developed neutropenic fever. The median duration to absolute neutrophil and platelet count recovery was 18 (range 12-42) and 27 (range, 12-42) days, respectively. Three (4.2%) patients died within 30 days and 11 (15.5%) within 8 weeks of initiating VDTPACE. Conclusions: VDTPACE is an effective therapy in relapsed MM but is associated with significant morbidity and short-term mortality. It appears to be more effective when followed by an autologous or allogeneic SCT.

8587 Background: Patients (pts) undergoing an auto-transplant (ASCT) for multiple myeloma (MM) have disease assessment approximately 100 days later. This result may direct decisions of further therapy versus observation. However, some pts continue to experience a decline in their serum or urine monoclonal (M) - protein after day 100 without more therapy. Little is known about the prevalence and significance of this phenomenon. Methods: We identified 903 MM pts who underwent ASCT within 12 months (mos) of diagnosis (Dx) at our institution. Their day 100 post-ASCT M-protein from serum and urine electrophoresis with immunofixation as well as serum free light chains were compared to subsequent values during follow-up. The IMWG criteria were used to evaluate response. Results: Of the pts included, 510 (56%) were male and median age at ASCT was 59 (range 28-76). Median follow up from Dx and ASCT was 82 mos (95% CI; 75 - 86) and 74 mos (95% CI; 70 - 79) respectively. There were 453 (50%) pts seen in follow-up who had not achieved a CR at Day 100 nor initiated on maintenance therapy. Of these pts, 167 (37%) had a further decrease in their M-protein after day 100 at a median of 9.4 mos (95% CI; 8 – 10) post-ASCT. Given the time taken for maximal response, we assessed patients’ clinical response at one year post-ASCT. Compared to patients who did not have further clinical response between day 100 and 1 year, pts experiencing further response had a longer time to next therapy (TTNT) (43 mos vs. 17 mos, P < 0.001) as well as overall survival (OS) (96 mos vs. 62 mos, P < 0.001). Positive predictors for continued response included having an IgG isotype, evolution from a pre-existing MGUS, smoldering myeloma or solitary plasmacytoma and a Day 100 bone marrow plasma cell < 3%. In a multivariate analysis, elevated creatinine at Dx and lack of continued response predicted for shorter TTNT and OS post-ASCT. Older age and high-risk MM by FISH also predicted a shorter OS. Conclusions: In MM pts undergoing ASCT, continued M - protein response was seen in a third of the pts lacking a CR at day 100. This phenomenon appears prognostic and must be considered when interpreting studies evaluating post-ASCT response and the need for further therapy.

8583 Background: Poor prognosis and therapy exhaustion have been associated with reduced QOL in RRMM. In MM-003, a randomized, multicenter, open-label phase 3 trial, POM + LoDEX (n = 302) significantly improved progression-free and overall survival vs. high-dose dexamethasone (HiDEX; n = 153) in pts who failed lenalidomide (LEN) and bortezomib (BORT) and progressed on their last therapy. This analysis evaluated QOL changes in these pts. Methods: To assess pt-reported outcomes, cross-sectional and longitudinal analyses were performed. Minimal important differences for 5 clinically relevant EORTC QLQ-C30 domains (Global Health Status, Physical Functioning, Fatigue, Emotional Functioning, and Pain) were calculated as meaningful change thresholds (1 standard error of measurement) from baseline through cycle (C) 5. Time to QOL worsening was compared between arms using the Kaplan-Meier method. Results: Favorable trends were observed for POM + LoDEX vs. HiDEX in each of the 5 relevant domains. The cross-sectional analysis indicated statistically or marginally significant (P < .10) differences favoring POM + LoDEX in Global Health Status (C2, 4), Physical Function (C2, 3, 4), Emotional Function (C2, 3, 4), and Fatigue (C2) scores. Longitudinal comparisons between arms confirmed the significance of score changes for Global Health Status (C2; P = .01), Physical Functioning (C3 and 4; P = .018 and .028, respectively), Emotional Functioning (C3; P = .018), and Fatigue (C5; P = .008) for POM + LoDEX vs. HiDEX. HiDEX pts exhibited clinically meaningful worsening in Global Health Status and Physical Functioning scores vs. POM + LoDEX by C2 (P = .04) and C3 (P = .02), respectively. POM + LoDEX extended median time to meaningful worsening vs. HiDEX for Global Health Status (114 vs. 85 days, P = .05), Physical Functioning (174 vs. 106 days; P = .09), Fatigue (113 vs. 60 days; P = .02), Emotional Functioning (190 vs. 124 days; P = .04), and Pain (147 vs. 113 days; P = .2). Conclusions: In heavily pretreated pts who failed LEN and BORT, POM + LoDEX resulted in better clinical outcomes as well as improvement in clinically relevant QOL measurements over the course of treatment. Clinical trial information: NCT01311687.

8581 Background: Autologous stem cell transplant (ASCT) improves survival in patients with multiple myeloma (MM). Recent studies have elucidated the relationship in ASCT between absolute lymphocyte count (ALC) recovery and improved survival, highlighting the importance of immune recovery. We conducted a retrospective analysis of patients with multiple myeloma to observe the impact of different measures of immune recovery at day 100 post-ASCT on outcome. Methods: Retrospective analysis of data from the existing clinical databases identified 1184 patients with multiple myeloma that underwent ASCT at Mayo Clinic between 1987-2011. Markers of immune recovery analyzed on day 100 status-post ASCT included ALC, monocyte count, and immunoglobulin levels. Kaplan Meier analysis was performed to determine progression free survival (PFS) and overall survival (OS). Results: Among the 1184 patients, median age at diagnosis of multiple myeloma was 57 (range, 23-75 yr), and median age at time of transplantation was 59 (range, 24-75 yr); 59% were male. The median OS and PFS post-transplant were 80 months and 34 months respectively. 62% of patients were alive 5-years post-transplant. The median OS was not improved with normal vs. abnormal IgG levels at day 100 (p=.298). In contrast, monocyte recovery was a significant predictor of OS. Patients with normal monocyte counts of greater than 0.3 x 10⁹ cells/L at day 100 showed superior survival (65 vs. 37 months, p= .001). Similarly, patients with normal monocyte recovery at day 15 post-transplant showed a significant survival benefit (68 vs. 50 months, p=.007). Early ALC recovery, which has been shown to be a positive prognostic indicator at day 15 post-transplant, was not prognostic at day 100 (p= .960). Conclusions: The present study further elucidates prognostic indicators after ASCT for MM highlighting the importance of various markers of immune recovery. Immunoglobulin recovery was not associated with superior survival, while monocyte recovery at day 15 and day 100 post-transplant translated to an improved survival and requires further study. It may be hypothesized that early immune system reconstitution may have a positive effect against disease post-transplant.

8541 Background: Achievement of a complete response (CR) to treatment is an important predictor of outcome for patients (pts) with myeloma (MM). The goal of the current study was to assess whether the treatment that resulted in CR has any impact on the outcomes. Methods: We identified 462 pts with MM, who fulfilled the IMWG criteria for CR, seen at Mayo Clinic between 1991 and 2011. The treatment was classified into groups by the regimen that led to CR (Table), and also based on whether an autologous stem cell transplant (ASCT) was part of the regimen. The remaining 21 pts had a variety of regimens and are not included in the Table. Results: The median age at diagnosis was 58.5 yrs (27.1–82.3 yrs) with 56% males. The overall survival (OS) from diagnosis for the entire cohort was 10.7 yrs (95% CI; 9.3, NR). The median interval from diagnosis to the recorded CR was 10.3 mos (range 1- 170), with 272 (58.4%) and 385 (82.7%) obtaining a CR in <12 mos and <24 months from diagnosis. We first compared the outcomes based on whether ASCT was part of the regimen; 328 had an ASCT while 117 pts received only chemotherapy. Median time to progression (TTP) following a CR was 5.1 yrs for the ASCT group compared with 5.5 yrs for the rest (P=0.3). Median OS from CR was 9.1 yrs for the ASCT group and 7.5 yrs for the rest (P=0.5) and OS from diagnosis was 10.1 yrs for the ASCT group and 12.6 for the rest (P=0.5). Examining the outcomes based on the regimen utilized showed that the TTP and OS from CR as well as OS from diagnosis were similar for all the groups (Table). Among pts who had a CR within a year of diagnosis, there were no differences in terms of the TTP or OS from the onset of CR or from diagnosis between the ASCT vs. chemotherapy groups or between the different regimens (P=NS for all comparisons). Conclusions: The current study highlights an important message regarding CR in MM. The results suggest that the prognostic value of CR is independent of the nature of therapy, and likely reflects the contribution of disease biology to obtaining a CR. [Table: see text]

8528 Background: RRMM patients (pts) who fail lenalidomide (LEN) and bortezomib (BORT) have poor prognosis. High-risk cytogenetics predict shorter survival. POM + LoDEX has demonstrated efficacy in pts with prior LEN and BORT and high-risk cytogenetics. MM-003 is an open-label, multicenter, phase III trial comparing POM + LoDEX vs. HiDEX in RRMM pts who failed LEN and BORT treatment (Tx) and have progressed on their last therapy. Methods: Pts must have been refractory to the last prior Tx (progressive disease [PD] during or within 60 days) and failed LEN and BORT after ≥ 2 consecutive cycles of each (alone or in combination). Randomization was 2:1 to POM 4 mg D1–21 + DEX 40 mg (20 mg for pts aged > 75 y) weekly; or DEX 40 mg (20 mg for pts aged > 75 y) D1–4, 9–12, and 17–20 (28-day cycles). Tx continued until PD or unacceptable adverse events (AEs). The primary endpoint was progression-free survival (PFS). Secondary endpoints included OS and AEs. This analysis examined pts meeting modified high-risk cytogenetic criteria—del(17p13) and/or t(4p16/14q32). Results: 302 pts received POM + LoDEX, and 153 pts received HiDEX. 225 and 107 pts, respectively, were evaluable for cytogenetics. Baseline characteristics were similar. Median PFS and OS were significantly longer with POM + LoDEX vs. HiDEX, regardless of cytogenetic risk (Table). The most common grade 3/4 AEs were neutropenia, anemia, and infection (Table). Discontinuation due to AE was low: 4% vs. 6% (high risk) and 10% vs. 4% (standard risk). Conclusions: Median PFS and OS were significantly longer with POM + LoDEX vs. HiDEX in pts with cytogenetically-defined high-risk disease, consistent with results from the intent-to-treat population. Tolerability was acceptable. POM + LoDEX should be considered a new Tx option in pts failing LEN and BORT. Clinical trial information: NCT01311687. [Table: see text]