Kumar, Shaji

TPS8057 Background: Multiple myeloma (MM) is the second most prevalent blood cancer, representing approximately 1% of all cancers. Although overall survival has improved in recent years due to new approved agents, the vast majority of MM patients (pts) ultimately stop responding to treatment. Moreover, about a quarter of MM pts characterized as “high risk” experience limited benefit from existing treatments. Seminal genomic sequencing research efforts, such as the MMRF CoMMpass study, have highlighted that a large number of MM cases harbor potentially actionable oncogenic molecular alterations and published reports on small numbers of cases suggest that Precision Medicine (PM) interventions clinically targeting such actionable drivers may benefit MM pts. These results suggest that PM approaches in MM are possible and should be further studied clinically. To that end, we have launched MyDRUG, a master protocol aimed at developing new myeloma regimens based on individual pt’s genomics. Methods: This study is a Phase I-II, multicenter master protocol in functional high risk MM patients (i.e patients having progressed from baseline treatment within 18 months without maintenance or 3 years on maintenance) with 1-3 prior lines of therapy. Patients are screened for actionable genomic alterations on the CLIA-grade MI-ONCOSEQ platform. Patients with actionable alterations are assigned to the appropriate targeted agent used in combination with a backbone regimen ixazomib, pomalidomide and dexamethasone (IPd), whereas patients without such alterations go on an immune arm (see Table). Inclusion criteria include measurable disease (as measured by M-protein and FLC) and acceptable hematologic and metabolic functions. A maximum of 12 evaluable pts will be accrued onto the phase I portion of each arm and an additional 21 evaluable phase II pts will be accrued onto each arm for a total of 27 evaluable pts at the MTD combination dose. The primary objective of the study is to evaluate ORR per IMWG consensus criteria. Secondary objectives are to assess adverse events (AEs), progression-free survival, and overall survival (OS). Experimental correlative aims include assessing molecular or clonal response, molecular and immune signatures of resistance/response, MRD. Clinical trial information: NCT03732703. [Table: see text]

TPS8052 Background: The most common translocation in multiple myeloma (MM) is t(11;14)(q13;q32), present in approximately 20% of cases. MM cells with t(11;14) usually have a favorable high BCL-2 level and inferior outcomes compared to standard risk MM. Venetoclax (VEN) is a potent, selective, orally available small-molecule BCL-2 inhibitor that induces cell death in MM cell lines and primary samples. VEN has single agent activity in relapsed/refractory MM (RRMM) with an acceptable safety profile, especially in t(11;14) MM; however, non- t(11;14) MM patients may benefit from single agent VEN and VEN incorporated in multi-agent RRMM regimens. Dexamethasone (d) promotes Bcl-2 dependence in MM resulting in sensitivity to VEN and this combination with bortezomib (Vd-VEN) has an acceptable safety profile with high response rates in heavily pre-treated MM. Combination therapy with daratumumab and bortezomib (DVd) has become a standard of care in RRMM. Our hypotheses are that the addition of VEN will improve upon this standard and be most effective in the t(11;14) positive subset. Methods: Eligibility criteria include RRMM with measurable disease, not bortezomib refractory, platelet count > 100K. t(11;14) is an integral biomarker with status (positive or negative) established at registration. After a Ph1 study to determine the recommended phase 2 VEN dose, patients are randomized to DVd +/- VEN [stratified by prior lines of therapy and R-ISS]. The primary Ph2 objectives are to compare 8-cycle minimal residual disease (MRD) negative rate and to inform the role of t(11;14) as a biomarker. The Ph2 design proposed by Freidlin et al. follows a decision algorithm as outlined in the table below. Simulations were run to establish an optimal sample size given various parameters including biomarker prevalence and power to make appropriate decisions for a Ph3 design. Target Ph2 accrual is 240 patients with a 1/3 positive:2/3 negative t(11;14) split. Clinical trial information: NCT03701321. [Table: see text]

e19519 Background: NSMM is a rare subtype of myeloma that has not been well characterized in the era of novel agent induction therapy. Thus, we evaluated the clinical and cytogenetic features of patients with newly diagnosed NSMM evaluated at our institution. Methods: We evaluated all NSMM patients seen at the Mayo Clinic, Rochester from 2008-2017 based on the absence of a detectable monoclonal protein in their serum and urine electrophoresis and having a concurrent involved serum immunoglobulin light chain of less than 5 mg/dL. Survival analysis was performed by the Kaplan-Meier method and clinical and cytogenetic features were reported descriptively. Results: This cohort consisted of 30 consecutive patients with NSMM with a median age of 62 years (40-79) of which 16 (53%) were male. The median bone marrow plasma cell involvement was 70% (Range: 0 – 100). There were 3/25 (12%) patients who presented with a creatinine of 2 mg/dL or greater and 6/23 (26%) patients who presented with hypercalcemia (11 mg/dL or greater). The ISS classification of this cohort is as follows: Stage 1- 8 (36%) patients, Stage 2- 3 (14%) patients and Stage 3- 11 (50%) patients. There were 6 (21%) out of 28 patients with high risk cytogenetics (either del 17p, t(4;14), t(14;16) or t(14;20). The distribution of primary cytogenetic abnormalities among this cohort was as follows: t(11;14) – 16 (57%), t(4;14) – 1 (4%), trisomies – 6 (21%) and other - 5 (13%). The median overall survival (OS) for patients in this cohort was 59 months (95% CI: 34 – 64). In comparison to a control cohort of newly diagnosed secretory myeloma patients matched for age, gender and year of diagnosis in a 1:2 ratio, the median OS was worse for the NSMM cohort but this was not statistically significant (59 vs. 92 months, p = 0.257). Conclusions: Patients diagnosed with NSMM had a predisposition towards having a t(11;14) primary cytogenetic abnormality. In the era of novel agent induction therapy, they may have a survival outcome that may be worse than newly diagnosed secretory myeloma patients.

e19503 Background: The risk of venous thromboembolic events (VTE) despite mandatory thromboprophylaxis (TPx) in patients with multiple myeloma (MM) receiving contemporary lenalidomide (Len)-based regimens is not well-defined. Methods: Medline, Embase, and CENTRAL databases were queried to identify phase 1-3 clinical trials of Len-based regimens with mandatory TPx published until April 2018. Random effects meta-analysis was performed using CMAv3 software to obtain crude, and per 100 patient-cycle incidence rate (IR). Prespecified subgroup analyses were performed to obtain IR for VTE by (1) line of treatment (newly diagnosed [ND], relapsed/refractory [RR] and maintenance [Mx] phase) and (2) different Len-based regimens. Results: We screened 1069 citations and analyzed data from 43 trials with 8696 patients, including 17 in ND, 23 in RR and 3 in Mx phase. 12 out of 43 were Phase 3 randomized controlled trials. The overall incidence of VTE in 8696 patients was 4.6% (95% CI, 3.7-5.8%), with 1.0 event (95% CI, 0.7-1.4%) per 100 patient cycles. In patients with NDMM (n = 3295), 193 (5.9%) experienced VTE with a pooled IR of 0.9 (95% CI, 0.3-2.3) per 100 patient-cycle. Among RRMM patients (n = 3981), 251 (6.3%) experienced VTE with a pooled IR of 1.0 (95% CI, 0.4-2.3) per 100 patient-cycle. The incidence of VTE was highest with the following triplet regimens: Rd + Proteasome inhibitor (PIs) and Rd + Anthracycline (Ac) [+/- Vincristine], with the latter having a high risk of VTE regardless of the treatment phase (table). With Len Mx (n = 1420), 38 (2.7%) patients had VTE, with a pooled IR of 0.2 (95% CI, 0-2.1) per 100 patient-cycle. Conclusions: Patients with MM undergoing treatment with Len-based regimens remain at risk of VTE despite current TPx strategies. The estimates of VTE IR provided by this analysis can guide clinicians in assessing treatment-related risk of VTE in this setting. [Table: see text]

8049 Background: Monoclonal gammopathy of undetermined significance (MGUS) is rare in young patients (pts; age <40 years at diagnosis), with a prevalence of < 0.3%, representing approximately 2% of all patients with MGUS. We hypothesized that MGUS detected in pts <40 years of age may be associated with a higher risk of progression. Methods: We identified 249 pts with MGUS <40 yrs old, evaluated at Mayo Clinic, Rochester from 1997 to 2016. The endpoint was time to progression assessed by Kaplan-Meier method. Results: 119 were male, 130 were female. Most (n= 179, 72%) were diagnosed between the ages of 30-39. The type of MGUS was IgG 69%, IgA 10%, IgM 15%, and other 5%. 135 pts (54%) had concurrent immune-related conditions, including autoimmune, inflammatory, and infectious disorders at the time of diagnosis of MGUS. Pts without immune-related conditions tend to have higher M protein compared to pts with immune-related conditions (mean, 0.36 gm/dl VS 0.20 gm/dl, p =0.057). During follow up, the M protein resolved in 36 patients. The M protein was more likely to resolve in pts with immune-related conditions compared with pts without immune-related conditions (RR 1.91, 95% CI 1.02-3.59). Progression was seen in 16 pts: 9 smoldering multiple myeloma (SMM), 4 multiple myeloma (MM), 1 macroglobulinemia, 2 non-Hodgkin’s lymphoma. The rate of progression to SMM, MM, or related disorder at 5 and 10 years was 6.0% and 13.8%, respectively. The size of M protein was a significant risk factor for progression (HR 4.23, 95% CI 2.17-7.91) The risk of progression at 5 and 10 years for pts with immune-related conditions concurrently present when MGUS was first diagnosed was 1.5% and 10.1% respectively; corresponding rate in pts without immune-related conditions at the time of diagnosis was higher at 12.3% and 18.9%, respectively (p =0.016), (HR 2.36, 95% CI 0.85-6.52). Similar results were seen when patients in whom the M protein resolved were excluded. Conclusions: Young patients with MGUS may have a higher risk of progression, 1.4% per year; approximately 50% are diagnosed in the setting of immune-related disorders. When occurring in the setting of immune related disorders, the M protein is smaller, more likely to resolve, and may have a lower risk of progression than in pts in whom MGUS is detected without concurrent immune-related disorder.

8039 Background: Treatment of MM has evolved significantly over the past decade, with increasing use of multi-drug combinations for initial therapy. In addition, supportive care approaches have also improved. We examined how these improvements have translated to survival outcomes in patients with newly diagnosed MM. Methods: Patients (n=3449) with a diagnosis of MM made between 2004 and 2017 and seen at Mayo Clinic within six months of the diagnosis, were included in this analysis. Patients were divided into three groups based on the year of diagnosis; group 1- 2004-07 (n=831), group 2-2008-12 (n=1161), and group 3-2013-17 (n=1457). Survival of the groups were estimated using Kaplan-Meier method, and compared using log rank test. Results: The median age was 64 years (22 to 96); 60% were male and 40% were female. 14% were >75 years, 33% were aged 65-75 and 53% were <65 years. The median overall survival for the whole cohort was 5.7 years (95%CI; 5.4, 6.3). The median OS for the groups 1, 2 and 3 were 3.9, 6.3 and NR, respectively; p<0.001. The 4-year survival estimates were 50%, 62%, and 75%, respectively. We then explored the improvements in patient subgroups. While all patients experienced improvements in OS over time, improvement in group 3 was most prominent for those >75 years. In patients <65 years, the 4-yr OS for groups 1, 2 and 3 were 57, 71, and 79% respectively. In patients 65-75 years of age, the 4-yr OS for groups 1, 2 and 3 were 48, 60, and 75% respectively. In patients >75 years, the 4-yr OS for groups 1, 2 and 3 were 24, 35, and 56% respectively. While patients with high-risk disease did not see as much benefit in the earlier period, substantial progress was seen in the last group. The 3-yr OS for patients with high-risk cytogenetics were 52, 55, and 73% for groups 1, 2 and 3 compared to 67, 75, and 85% for standard-risk cytogenetics respectively. 2067 patients were staged according to the International Staging System and the median OS for stages 1, 2 and 3 were 6.5, 4.6 and 2.4 in group 1; 9.2, 6.6 and 3.5 in group 2 and NR for any of the stages in group 3. Conclusions: The results confirm continued improvement in survival of newly diagnosed multiple myeloma patients, including elderly and high-risk MM.

8035 Background: D-Rd significantly reduced the risk of progression/death by 44% in transplant-ineligible NDMM pts vs Rd in the phase 3 MAIA study. To examine the impact of age on efficacy/safety of D-Rd vs Rd in this population, a subgroup analysis was conducted in pts <75 and ≥75 y of age. Methods: Transplant-ineligible NDMM pts were randomized 1:1 to Rd ± DARA; stratification was based on age (<75 vs ≥75 y), ISS (I, II, III), and region (North America vs Other). Pts received 28-day cycles of either R 25 or 10 mg (based on renal function) PO QD on Days 1-21 and either d 40 or 20 mg (based on age or BMI) PO/IV weekly until progression. In the D-Rd arm, pts received daratumumab 16 mg/kg IV QW for Cycles 1-2, Q2W for Cycles 3-6, and Q4W thereafter until progression. PFS is the primary endpoint. Results: Among 737 randomized pts (D-Rd, n=368; Rd, n=369), 321 (44%) were ≥75 y of age. For D-Rd vs Rd, relative median dose intensity for R was 79% vs 93% for <75 y subgroup and 66% vs 89% for ≥75 y subgroup, respectively. After median follow-up of 28 mo, significant PFS benefit of D-Rd vs Rd was maintained in both <75 and ≥75 y subgroups (Table). Deeper responses and MRD-negative rate (10-5 threshold) remained higher with D-Rd vs Rd in both subgroups (Table). Most common (≥10%; D-Rd/Rd) grade 3/4 TEAEs in ≥75 y pts were neutropenia (60%/41%), lymphopenia (19%/12%), anemia (16%/22%), pneumonia (15%/10%), leukopenia (12%/6%), and thrombocytopenia (8%/11%). Fewer pts receiving D-Rd vs Rd discontinued treatment due to TEAEs (<75 y: 5% vs 12%; ≥75 y: 10% vs 21%). Conclusions: D-Rd pts received less R vs Rd group regardless of age. Efficacy of D-Rd in <75 and ≥75 y pts was consistent with the ITT population, and D-Rd demonstrated acceptable tolerability regardless of age. Together with the phase 3 ALCYONE study, these studies confirm clinical benefit of daratumumab plus standard-of-care in transplant-ineligible NDMM pts ≥75 y of age. Clinical trial information: NCT02252172. [Table: see text]

8034 Background: Minimal residual disease (MRD) assessment in multiple myeloma (MM) has improved our ability to assess disease activity, resulting in more advanced prognostication. While MRD assessment remains confined to the bone marrow (BM) plasma cell population, serum studies including immunofixation (IFE) are required to complete response evaluation. The significance of those who are MRDneg yet have detectable monoclonal protein through IFE remains unclear. Methods: We retrospectively studied 256 MM patients who had MRD assessment via the Euroflow multiparametric flow cytometry on the BM with concomitant serum IFE testing. Patients who were MRDneg were included in the study. Outcomes included probability of disease progression (PD) at 1 year. The Cox-proportional hazards model was used to compare probability of PD among different groups. Time to progression (TTP) was calculated as the difference from date of MFC analysis to PD in months. Results: Among the entire cohort, 178 (70%) patients were MRDneg and median follow-up from MRD assessment was 6.3 months. Among these patients, 74 (42%) had a positive IFE at the time of MRD analysis. Within the MRDneg/IFEpos group, 31 (42%) patients remained IFEpos after a median follow up of 5.5 mo from initial MRD/IFE testing while 34 patients eventually became IFEneg after a median of 2.8 mo with no subsequent IFE available in 9 patients. The 1 year probability of PD in the MRDneg/IFEneg group was 20% compared to 41% in the MRDneg/IFEpos group (P < 0.01, Wilcoxon test). When comparing subsequent IFE status in those who were MRDneg/IFEpos, those who remained IFEpos had a trend towards shorter TTP compared to patients who later became IFEneg. Conclusions: Persistent monoclonal protein in the face of MRD negativity predicts for a shorter TTP. This likely reflects persistent disease that was not sampled on the BM aspirate in many of these patients compared to those who eventually become IFEneg with a trend towards longer TTP owing to the prolonged half-life and therefore clearance of M protein. This supports the current strategy of assessing for MRD at the time of suspected complete response to reduce the chance of positive MRD tests and thus avoidance of multiple BM exams.

8031 Background: Our prior studies identified the prognostic significance of ≥400 cPCs/150,000 analyzed events quantified by MFC in NDMM. We evaluated if a similar quantification of cPCs using MFC can add prognostic value to the current R-ISS classification of NDMM pts. Methods: We evaluated all NDMM pts seen at the Mayo Clinic, Rochester from 2009-2017 who had their peripheral blood samples evaluated by 6-color MFC prior to therapy. The cPCs detected were reported as the number of clonal events/150,000 collected total events. Survival analysis was performed by the Kaplan-Meier method and differences assessed using the log rank test. Results: This cohort consisted of 566 consecutive pts with NDMM with a median age of 66 years (27-95). The distribution of the R-ISS classification of this cohort is as follows: Stage 1- 128 (23%) pts, Stage 2- 369 (65%) pts and Stage 3- 69 (12%) pts. The median number of cPCs was 59 (0-46,412) / 150,000 events. The median time-to-next-treatment (TTNT) and overall survival (OS) for pts with ≥400 cPCs (n = 140, 25%) was 19 months and 46 months compared with 34 months and 77 months for those with < 400 cPCs respectively (n = 426, 75%) (p < 0.001 for both). The median TTNT and OS for pts based on their R-ISS classification as well as with and without the presence of ≥400 cPCs by MFC was as follows in the following Table. Conclusions: Quantifying ≥400 cPCs/150,000 analyzed events by MFC can potentially upstage the R-ISS classification of a subset of NDMM pts with stage I and II disease and identify those pts with a worse than expected survival outcome.[Table: see text]

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]