Dimopoulos, Meletios Α.

e19505 Background: CFZ combined with dexamethasone is approved to treat pts with RRMM, with CFZ given once-weekly at 70 mg/m2 (Kd70 QW) or twice-weekly at 56 mg/m2 (Kd56 BIW). No randomized trials have directly compared Kd70 QW with Kd56 BIW. We performed a post hoc comparison between pts who received Kd56 BIW in the ENDEAVOR trial and pts who received Kd70 QW in the A.R.R.O.W. or CHAMPION-1 trials. Methods: Data were analyzed from 3 trials of CFZ in RRMM: A.R.R.O.W. (240 pts in Kd70 QW arm; 2–3 prior therapies and refractory to most recent therapy), CHAMPION-1 (104 pts received Kd70 QW; 1–3 prior therapies), and ENDEAVOR (464 pts in Kd56 BIW arm; 1–3 prior therapies). Pts who received Kd70 QW in A.R.R.O.W. and CHAMPION-1 were pooled and compared with pts who received Kd56 BIW in ENDEAVOR. As study populations slightly varied among the 3 trials, an analysis of safety and efficacy was performed in a subgroup of pts who received 2–3 prior therapy lines and were not refractory to bortezomib (BTZ). Also, we performed regression analyses (controlling for age, ISS stage, BTZ and lenalidomide refractory status, and number of prior regimens) among all pts in the trials who received Kd70 QW or Kd56 BIW. Results: Among BTZ non-refractory pts with 2–3 lines of prior therapy, median progression-free survival (PFS) was 12.1 months (95% CI 8.4–14.3) for Kd70 QW (n = 146) and 14.5 months (95% CI 10.2–NE) for Kd56 BIW (n = 217), and the overall response rate (ORR) was 69.9% (95% CI 61.7–77.2) for Kd70 QW and 72.4% (95% CI 65.9–78.2) for Kd56 BIW. The rate of grade ≥3 adverse events (Kd70 QW vs Kd56 BIW) was 67.6% and 85.3%; among adverse events of interest, the grade ≥3 rate was 1.4% and 5.1% for cardiac failure, 3.4% and 6.0% for renal failure, and 5.5% and 15.7% for hypertension. Kd70 QW represents a convenient and well-tolerated treatment modality for pts with RRMM. In a Cox proportional hazards model, the hazard ratio for PFS (Kd70 QW vs Kd56 BIW) was 0.91 (95% CI 0.69–1.19), and in a logistic regression model the odds ratio for ORR (Kd70 QW vs Kd56 BIW) was 1.12 (95% CI 0.74–1.69). Conclusions: This post hoc analysis suggests that once-weekly Kd70 has a comparable benefit-risk profile to twice-weekly Kd56. Clinical trial information: NCT02412878, NCT01677858, NCT01568866.

8027 Background: A.R.R.O.W. demonstrated superior progression-free survival (PFS) with once-weekly K (70 mg/m2)-dexamethasone (Kd70) vs twice-weekly K (27 mg/m2)-dexamethasone (Kd27) in relapsed and refractory multiple myeloma (RRMM) pts, regardless of age. Weekly Kd70 is US-approved for relapsed or refractory MM (1–3 prior therapy lines). For a comprehensive fitness measure, frailty scales were developed incorporating age, comorbidities, and functional status. (Palumbo Blood 2015; Facon Blood 2015). Here we assessed post hoc pt outcomes by frailty status. Methods: PFS and safety were assessed by treatment arm and a frailty algorithm incorporating age, medical history–derived Charlson Comorbidity Index, and ECOG performance status; pts with frailty scores of 0, 1, or ≥2 were classified as fit, intermediate (int), or frail, respectively. PFS was assessed with the Kaplan-Meier method. Safety was assessed in pts who received ≥1 treatment dose. Results: Pt distribution by frailty status was generally balanced between arms (Table). Once-weekly Kd70 vs twice-weekly Kd27 resulted in median PFS for fit, int, and frail pts of 15.7 vs 5.7 (mos; HR 0.53 [95% CI, 0.33–0.86]), 11.1 vs 7.7 mos (HR 0.81 [95% CI, 0.55–1.19]), and 10.3 vs 6.6 mos (HR 0.76 [95% CI, 0.49–1.16]), respectively. Rates of grade ≥3 treatment-emergent adverse events (TEAEs) of interest were similar between treatment arms across frailty subgroups (Table). In the once-weekly Kd70 subgroups, there was no grade ≥3 peripheral neuropathy (PN); grade ≥3 cardiac failure rates were ≤4%. Conclusions: Once-weekly Kd70 resulted in PFS benefits vs twice-weekly Kd27 with a favorable benefit/risk profile regardless of frailty score as defined. These results support weekly Kd70 as a treatment option for both fit and frail RRMM pts. Clinical trial information: NCT02412878. [Table: see text]

8015 Background: Multiple myeloma (MM) is a heterogeneous disease with varying survival outcomes depending on the presence of certain genetic abnormalities. Common abnormalities include trisomies, translocations involving chromosome 14, and amplifications or deletions of chromosomes 1, 13, and 17. t(11;14), occurring in approx. 15% of patients (pts) with MM, is considered a standard risk abnormality, but recent data suggest that the prognosis may be inferior to what had been expected. This is of particular relevance as new therapeutic options such as the BCL-2 inhibitor venetoclax has been shown to be effective in t(11;14) pts. Methods: This was a multicenter study designed and conducted by the IMWG, to identify the outcomes of pts with t(11;14) using a retrospective cohort of pts. Pts with MM diagnosed between 2005 and 2015 with t(11;14) identified on FISH performed within six months (mos) of diagnosis, and with treatment details available and if alive, a minimum of 12 mos of follow up, were enrolled. Results: The current analysis includes 848 pts with a median age of 64.4 years; 60.0% are male. The median follow-up from diagnosis for the entire cohort was 45.7 mos; 84.7% of the pts were alive at the last follow up. ISS stage distribution included: Stage 1 (35.3%), Stage II (38.9%) and stage III (25.8%). The distribution of FISH abnormalities included: del 13q (14.5%), 1q amp (12.1%), del 17p or monosomy 17 (6.1%). Pts received initial therapy with different regimens: IMiD-24.3%, PI-41.0%, both-20.8% and 13.8% had no novel agent. The drug classes by line of therapy are shown in table. An early stem cell transplant (SCT) was used in 40.8% of pts. The median time to next treatment (TTNT) after initial treatment was 15.0 (95% CI: 12.2 to 17.7) mos. The median overall survival from diagnosis for the entire cohort was 82.5 (95% CI: 73.5 to 95.8) mos. Conclusions: This is the first study to examine the outcomes of a large group of myeloma pts with t(11;14) abnormality. Pts receiving a combination if a PI and an IMiD appear to have the best survival outcomes and thse receiving an early SCT appear to have excellent survival with median OS approaching 10 years. Additional pts are being accrued to this study and additional analysis examining the variables affecting response duration and survival will be presented. [Table: see text]

8014 Background: TCR-MM is defined as being refractory to immunomodulatory agents, proteasome inhibitors, and anti-CD38 mAbs, representing an urgent unmet medical need with a median OS of 3-5 months( Pick M et al, Eur J Haem 2018; Gandhi U et al, ASH 2018). Sd has shown a 26.2% overall response rate (ORR) in 122 patients (pts) with TCR-MM in the Phase 2b STORM study ( Chari A et al, ASH 2018). Here, we evaluate the OS of pts in the STORM study with Sd and in pts with bortezomib, carfilzomib, lenalidomide, pomalidomide, and daratumumab (“penta”)-exposed, TCR-MM from an observational cohort not receiving Sd. Methods: Data were drawn from STORM and a retrospective cohort from the nationally representative Flatiron Health Analytic Database (FHAD). All pts from both sources had penta-exposed TCR-MM. In order to align study populations, OS was evaluated in pts in STORM whose first therapy after their MM reached TCR status was Sd and in pts in the FHAD who received ≥1 therapy after their MM reached TCR status. The index date for this evaluation was the start date of treatment after their MM reached TCR status. A Cox proportional hazards regression model was performed to assess the survival impact of Sd. In STORM, ORR was assessed by an Independent Review Committee based on IMWG criteria. Results: In the FHAD, 69 pts with TCR-MM were identified. Characteristics of the two groups of pts were similar, except that pts in STORM were more heavily pretreated, had a higher frequency of high-risk MM, a longer time since initial diagnosis of MM, and higher baseline hemoglobin and platelet values. Among the 122 pts in STORM, 64 received Sd as their first therapy after their MM became TCR, and ORR was 32.8%. Among the 69 pts from FHAD, 37 received ≥1 therapy after their MM became TCR. Median OS (N = 64) was 10.4 months for pts receiving Sd in STORM and 5.2 months (N = 37) for pts not receiving Sd in FHAD (HR = 0.49, p = 0.0241). Conclusions: The prognosis of TCR-MM in the real-world population appears very poor. Within the limits of this analysis, median OS of pts receiving Sd as their first therapy after their MM becomes TCR is significantly better than those not receiving Sd, suggesting that Sd may be associated with an OS benefit in pts with TCR-MM. Clinical trial information: NCT02336815.

8004 Background: The primary objective of this phase 3 trial was to demonstrate progression free survival (PFS) improvement of isatuximab (Isa), a novel anti-CD38 monoclonal antibody, combined with pomalidomide (P)/dexamethasone (d) versus (vs) Pd. Methods: Patients (pts) with RRMM who received ≥2 prior lines, including lenalidomide (len) and a proteasome inhibitor (PI), refractory to last therapy were enrolled. IsaPd arm received Isa 10 mg/kg IV weekly for first 4 weeks (wks), then every 2 wks. Both arms received approved schedules of pom and dex (4mg PO days 1-21; 40mg [20mg if >75 yrs] PO or IV weekly) every 28 days until progression or unacceptable toxicity. Results: 307 pts (154 IsaPd, 153 Pd) were randomized and analyzed (ITT). Patient characteristics were well balanced across arms. Median age: 67 (36-86) yrs; median prior lines of therapy: 3 (2-11); estimated GFR: <60ml/min in 33.9% pts; 92.5% refractory to len, 75.9% to PI; and 19.5% pts had high-risk cytogenetics. At median follow-up of 11.6 months (mos), median PFS was 11.5 mos IsaPd vs 6.5 mos Pd; HR 0.596 (95% CI 0.44-0.81), P=0.001. PFS benefit was consistent across all major subgroups. ORR (≥PR) was 60.4% IsaPd vs 35.3% Pd, P<0.0001. VGPR rate or better was 31.8% IsaPd vs 8.5% Pd, and MRD negativity (NGS, 10-5) was seen in 5.2% IsaPd pts vs 0% Pd. At analysis date, overall survival (OS) was immature (99 events) but a trend to OS improvement in IsaPd (vs Pd) was observed (HR 0.687; 95% CI 0.461-1.023). Median treatment duration was 41 wks IsaPd vs 24 wks Pd; median Isa infusion (inf.) duration was 3.3h at 1st inf. and 2.8h at subsequent inf. Grade ≥3 AEs were observed in 86.8% IsaPd vs 70.5% Pd; 7.2% IsaPd and 12.8% Pd pts discontinued due to AEs; 7.9% IsaPd and 9.4% Pd pts died due to AEs. Inf. reactions were reported in 38.2% (2.6% grade 3-4) IsaPd. Grade ≥3 infections were seen in 42.8% IsaPd and 30.2% Pd, grade ≥3 neutropenia in 84.9% (febrile 11.8%) IsaPd and 70.1% (febrile 2.0%) Pd. Conclusions: IsaPd significantly improved PFS and ORR vs Pd, with a manageable safety profile. IsaPd is an important new treatment option for the management of RRMM. Clinical trial information: NCT02990338.

8000 Background: The diagnostic criteria for MM were revised in 2014, recategorizing ultra-high risk (i.e., 80% at two years) as active myeloma requiring therapy. The removal of patients at the highest risk of progression from the smoldering group requires reassessment of current risk stratification models. Methods: We designed a multicenter, retrospective study of SMM patients to develop a risk stratification model. Patients diagnosed with SMM on/after January 1, 2004 were included if they had no disease progression within 6 months, had baseline data from diagnosis (+/- 3 months), had a follow up of ≥1 year, and did not participate in a therapeutic trial of SMM. Various clinical and laboratory factors were explored to identify factors that predicted progression at 2 years. Univariate Cox regressions were run for each factor. For factors with p-values ≤ 0.25, optimal cut points were identified using Youden’s index. Binary factors were used in stepwise regression to fit multivariable Cox model and significant risk factors were determined (F-test). Results: Overall, 2004 patients were included (ages 26-93, 51% female). Factors independently associated with progression (optimal cutoffs) included: Serum M protein (2 g/dL), involved to uninvolved serum-free light chain ratio (20), and marrow plasma cell % (20%). Patients were stratified using the risk factors: Low- (0 factors), Intermediate- (1), and High-Risk (≥2). Previously used high risk markers such as Bence Jones proteinuria (≥500 mg/24 hours) and severe immunoparesis (50% decrease in uninvolved immunoglobulin levels) were both significant in univariate analysis, but were eliminated on step wise selection. Compared to the low risk group, intermediate- and high-risk groups had significantly higher rate of progression (Table). Within the high-risk group, having all 3 risk factors (n=61) versus 2 did not add to the model, with insufficient separation between 2 and 3 factors. Conclusions: We have developed a risk stratification model for SMM that incorporates revised cutoffs for previously used parameters (20/2/20) that can be universally applied. Additonal analysis are being conducted to develop models that utilize common cytogenetic abnormalities, as well as those without FLC given lack of availability of all tests across the world. [Table: see text]

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.

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]

8527 Background: Pts who have exhausted lenalidomide (LEN) and bortezomib (BORT) treatment (Tx) have a poor prognosis. A significant proportion of pts have RI with increasing incidence during disease course. POM + LoDEX has demonstrated efficacy in pts with prior LEN and BORT, including those with RI. MM-003 is an open-label, multicenter, phase 3 trial comparing POM + LoDEX vs HiDEX in RRMM pts who failed LEN and BORT and progressed on their last Tx. Methods: Pts must have failed LEN and BORT after ≥ 2 consecutive cycles of each (alone or in combination) and must have been refractory to last prior Tx (progressive disease [PD] during Tx or within 60 days). Pts with creatinine clearance (CrCl) < 45 mL/min were excluded. Randomization was 2:1 to POM 4 mg D1–21 + DEX 40 mg (20 mg for pts aged > 75 y) qw; or DEX 40 mg (20 mg for pts aged > 75 y) D1–4, 9–12, and 17–20 (28-D cycles). Tx continued until PD or unacceptable adverse event (AE). The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS) and AEs. This analysis examined pts with or without moderate RI (CrCl < 60 vs ≥ 60mL/min). Results: 302 pts received POM + LoDEX; 153 pts received HiDEX, 31% and 39% had moderate RI, respectively. Pts with moderate RI were more likely to be older (64% vs 36% aged > 65 y) vs no RI. Median follow-up was 4 mo. Median PFS and OS were significantly longer with POM + LoDEX vs HiDEX regardless of RI (Table). Similar AE rates for POM + LoDEX as well as HiDEX Tx were seen in pts with and without moderate RI (Table). Discontinuation due to AE was 5% vs 7% (no moderate RI) and 11% vs 5% (moderate RI). Conclusions: POM + LoDEX significantly extended PFS and OS vs HiDEX in pts with or without moderate RI. Tolerability of POM + LoDEX was acceptable across subgroups, with few discontinuations due to AE. Clinical trial information: NCT01311687. [Table: see text]

8517 Background: An increased risk of SPM in MM pts treated with len has been reported. We performed an IPD metanalysis to estimate the incidence of SPM according to len exposure. Methods: Randomized studies of MM, from PubMed and ASCO/IMW/ASH (after 2000), that met the following criteria, were included: randomization to treatment with len (len-trials); randomization to treatment including new drug but not len (no-len-trials); available SPM data. Primary aim was to estimate cumulative incidence of SPMs by len exposure, corrected for death (competing event). Results: Data from 6,383 pts (3,218 from 8 len-trials, 3,165 from 10 no-len-trials) were analyzed. Median age was 69 years. During follow-up (median=30 mos) 420 (6.6%) SPMs were reported: 188 (2.9%) hematologic and 232 (3.6%) solid cancers. Solid tumors occurred with similar incidence in all groups. Incidence of hematologic SPM was significantly higher in patients receiving len (3.2 vs 1.1, p=0.04), but risk is limited to patients treated with melphalan+len (4.1, 95%CI: 2.4-5.8) with no excess in other combinations (len without melphalan: 1.2, 0.0-2.6; melphalan without len: 1.1, 0.0-2.7) (p=0.003). The cumulative incidence of death for any cause was much higher than the risk of SPM. Conclusions: The risk of hematologic SPMs was higher in pts receiving melphalan+len. The benefit/risk profile of len treatment remains positive. Cumulative incidence (%) of SPMs and death (95%CI). [Table: see text]