Citations

8567 Background: Adjuvant osimertinib (osi) improves disease-free survival (DFS) in patients (pts) with resected, early-stage, EGFR-mutant (EGFRmut) NSCLC, yet the benefit of osi after CRT in pts with unresectable locally advanced NSCLC is unknown. Post-hoc analysis of the PACIFIC trial showed a lack of survival benefit with consolidation durva versus placebo in pts with EGFRmut NSCLC. Comparisons between consolidation durva and EGFR TKIs in unresectable EGFRmut NSCLC following CRT are lacking. Methods: We conducted a multi-institutional retrospective analysis of pts with stage III unresectable EGFRmut NSCLC (exon19 deletion, exon21 L858R), who received EGFR TKI or durva after ≥ 2 cycles of platinum-based chemotherapy plus definitive radiation therapy between 2015-2022. Baseline characteristics including age, sex, smoking history, PD-L1 status, and outcomes on DFS, overall survival (OS), and safety were collected. Multivariable (MVA) cox regression analysis was used for statistical analysis. Treatment-related adverse events (trAE) were defined using CTCAE 5.0. Results: Seventeen pts from 12 institutions received an EGFR TKI (osi, n=15; erlotinib, n=2), and 13 pts received consolidation durva. Median follow-up was 23 months. Median age of all pts was 61 years (IQR:52-72) and 76.7% were female. Most pts in both groups had never-smoked and had adenocarcinoma. All pts received ≥ 60 Gy of radiation with concurrent chemotherapy. PD-L1 expression was ≥ 50% in 1/10 (10%) pts treated with durva vs 6/13 (46.2%) treated with TKI, p=0.09. Median duration on treatment for EGFR TKI and durva was 12.2 months and 4.8 months, respectively. Pts treated with EGFR TKI had significantly longer 24-month DFS versus pts treated with durva after adjusting for stage (3A vs 3B vs 3C) (Table). Any grade tRAE occurred in 58.8% (10/17) of pts treated with EGFR TKI vs 38.5% (5/13) with durva. Grade > 3 tRAE occurred in 15.4% (1 pneumonitis and 1 AST/ALT elevation) of pts treated with durva but in none of pts treated with EGFR TKI. Three pts within each arm came off treatment due to toxicity (EGFR TKI: 1 pneumonitis and 2 dermatitis; durva: 1 of each pneumonitis, Type 1 diabetes, AST/ALT elevation). Conclusions: EGFR TKI therapy after definitive CRT was associated with significantly longer DFS compared to durva in this retrospective study of pts with stage III unresectable EGFRmut NSCLC, without unanticipated safety signals. Follow-up is ongoing and OS outcomes will be evaluated subsequently. Further investigation is warranted to define the optimal therapy for locally advanced EGFRmut NSCLC. [Table: see text]

e20032 Background: The introduction of anti-CD38 antibodies (daratumumab) in the treatment landscape of multiple myeloma (MM) has increased the progression-free survival (PFS) in recent years. Still, the ideal combination (Dara-IMiD vs. Dara-PI) of these drugs in patients with relapsed MM is unclear. Methods: We reviewed MM patients treated with daratumumab as second-line therapy at our institution from 2016 to 2022 to assess the outcomes with the different combination therapies. We used the Kaplan-Meier method to estimate PFS from the first relapse. Results: We identified 329 patients with a median age of 63.6 years (range: 27.1 – 90.4). Most of the patients received triplet induction therapy (95%) and upfront transplant (67%) as primary therapy. At the time of Dara initiation, 41% were refractory to IMiDs, 22% to PIs, 18% to both, and 18% to neither drug. Patients treated with Dara-IMiD had significantly better PFS than Dara-PI (28.7 months vs. 18.5 months, p < 0.01, respectively). In a subgroup analysis based on the FISH results, high-risk patients had similar PFS outcomes (24.3 vs. 10.2 months, p = NS, respectively), while standard-risk patients benefited significantly from the Dara-IMiD regimen (48.3 vs. 19.2 months, p < 0.01, respectively). Among patients treated with Dara-IMiD, those already refractory to IMiDs from the first line had significantly shorter PFS than those without IMiD resistance (14.9 vs. 43.3 months, p < 0.01, respectively). In addition, the lenalidomide-based combination resulted in significantly better PFS compared to pomalidomide in our cohort (40.5 vs. 19.2 months, p < 0.01, respectively). However, no difference was found in the IMiD refractory population (12.3 vs. 15.1 months, respectively). Finally, no significant differences were seen between Dara-IMiD and Dara-PI in patients only refractory to IMiDs (16.1 vs. 12.8 months, p = NS, respectively). Conclusions: While further studies are required to adjudicate the best combination, we conclude that Dara-IMiD might be more effective in patients with relapsed MM, especially for patients not refractory to IMiD at first line. [Table: see text]

e20011 Background: Drug refractoriness is an important factor determining choice of next therapy and prognosis in multiple myeloma (MM). It is debatable whether refractoriness to a drug varies among patients (pts) with MM progressing on different administration schedules of the drug. Outcomes of MM pts refractory to different doses of lenalidomide have been previously described, but similar data about proteasome inhibitors (PIs) are limited. In this study, we assessed the impact of refractoriness to different schedules of bortezomib (V) on outcomes with subsequent therapies in MM pts. Methods: We retrospectively reviewed MM pts at our center diagnosed between January 2004 and December 2018, who progressed on/ after receiving first line therapy with V containing regimens. At first relapse, we divided pts into 3 groups- MM progressing on or within 60 days of receiving (1) 1-1.3 mg/m2 V once weekly or more frequently (Standard Dose Refractory), (2) 1-1.3 mg/m2 V once every 2 weeks or less frequently (Low Dose Refractory), and (3) MM progressing at least 60 days after stopping V (Not Refractory). In addition to V, we classified pts as being refractory to cyclophosphamide and immunomodulatory drugs (IMiDs) at first relapse. We classified salvage regimens into daratumumab (Dara), PI, IMiD, PI+IMiD, and VDTPACE like regimens. We then assessed progression free survival (PFS) and overall survival (OS) for next line therapy, and for next V containing therapy using Kaplan Meier and Cox models. Results: A total of 302 pts were included. Median age at diagnosis was 62 years and 60% pts were male. Overall, 23%, 31%, and 27% were International Staging System (ISS) stage I, II, and III respectively; 40% had high risk FISH as per mSMART. Of the 302 pts, 134 (44%) pts received another V containing regimen after the first line therapy at any time during the disease course. Using a multivariable Cox model to adjust for ISS, high risk FISH, refractoriness to other drugs, duration of first line therapy, and treatment received at relapse, the Not Refractory Group had a better PFS for both 2nd line therapy and the next V containing line of therapy, while no significant differences were seen between the Standard Dose Refractory and Low Dose Refractory groups. OS differences followed the same trend but were not statistically significant (Table). Conclusions: On multivariable analysis, the PFS did not differ among standard dose vs low dose refractory pts, and both were significantly inferior to pts not refractory to V. These data suggest that refractoriness to V might not be a dose dependent phenomenon. [Table: see text]

e20010 Background: For the year 2019, the United States age-adjusted rate of new Multiple Myeloma (MM) cases was 6.8 per 100,000 people and the age-adjusted death rate was 3 per 100,000 people. Vitamin D Deficiency (VDD) and associated complications are very common in MM patients. Aim of our study was to evaluate the prevalence and risk of VDD in patients with MM and VDD associated disability and mortality in the VDD patients. Methods: We performed a cross-sectional retrospective analysis of Nationwide Inpatient Sample data 2016-2018. Adults hospitalizations with MM were identified using ICD 10 code. Hospitalized patients were grouped into patients with VDD and without VDD. We ran chi square, unpaired-t test and mixed-effect survey logistic regression analysis to find out odds ratio and 95%CI showing outcomes of VDD in MM patients. Results: We found 330,175 hospitalizations with MM. Of these 11,480 were noted to be patients with VDD with higher prevalence (0.64% vs 0.37%) of and strong association (aOR:1.41, 95%CI:1.35-1.47) with MM in comparison without MM. Amongst MM, females [1.50, 1.49-1.51], black race [1.23, 1.22-1.24], urban teaching hospitals [1.22, 1.22-1.23], and hospitals in mid-west region [1.30, 1.29- 1.32] had higher prevalence odds of VDD compared with males, white race population, rural hospitals and hospitals in northeast region. (p<0.0001) Patients with VDD had higher prevalence and strong association with higher morbidity [5.1% vs 3.9%, 1.24,1.14-1.36; c-value=0.67], severe/extreme disability [77.2% vs 73.3%, 1.26, 1.20-1.33; c-value=0.73], and discharge to locations other than home [51.15% vs 45.69%, 1.29, 1.23-1.34; c-value=0.69] in comparison without VDD. (p<0.0001) [Table]. Conclusions: Significant poor outcomes warrant early identification of VDD and role of same hospitalization vitamin D replacement amongst MM patients with higher risk. [Table: see text]

8056 Background: Multiple myeloma (MM) is preceded by monoclonal gammopathy of undetermined significance (MGUS). A transitional stage of smoldering multiple myeloma (SMM) can be identified between MGUS and MM. While MGUS carries a steady risk of progression of 1% per year, SMM is more heterogenous with nearly 40% of patients progressing in the first 5 years, 15% in the next 5 years, reaching the same low risk as MGUS after 10 years. SMM with its high risk of progression in the initial years after diagnosis presents a viable opportunity for early intervention. For implementing early intervention, the ability to identify SMM patients at the highest risk of progression is critical. This has led to the development of several risk stratification systems. Using these systems high risk SMM patients studied in phase 3 trials demonstrated delayed progression to MM and improved overall survival with early initiation of therapy. However, these approaches showed limited specificity exposing patients at lower risk of progression to therapy. To date, identifying high risk SMM patients and confirming disease stability in low risk SMM patients remain an important clinical need. Genomic instability has been shown to be a sensitive indicator of disease progression in cancer. Telomere dysfunction is an early event in genomic instability. The 3-dimensional spatial profiling of telomeres using TeloView technology allows for quantification of telomere dysfunction, and was shown to be instrumental in risk stratification of cancer patients generally, but particularly in selected hematological malignancies. Importantly, in a previous SMM proof-of-concept study telomeric parameters measured by TeloView technology was found to be significantly different between SMM patients who progressed to active MM within 2 years and those who remained stable for over 5 years. Methods: We analyzed a total of 162 SMM patients using TeloView technology. 88 patients were employed as training dataset in Receiver Operating Curve (ROC) modeling to develop a scoring model that stratifies individual SMM patients based on risk of progression to full stage MM. An additional cohort of 74 SMM patients was used for blind validation of the developed scoring model. Results: We report area-under-the-curve (AUC) in the ROC analysis of 0.8 (accuracy 80%) achieved by the scoring model developed using the training dataset. Furthermore, the independent blind validation achieved positive predictive value of 83% and negative predictive value of 71%, with sensitivity and specificity of 80% and 76% respectively. Conclusions: The result of this study supports presenting TeloView as an accurate prognostic biomarker which appears able to stratify SMM patients into their respective risk groups with high sensitivity and specificity. This will potentially allow for evidence-based treatment decisions for high risk SMM patients and confident monitoring of stable patients.

8051 Background: Patients with multiple myeloma (MM) that do not respond to initial therapy have worse outcomes compared to primary responders, and effective treatments are lacking in this population. However, the outcomes of primary refractory disease in the modern treatment era have not been studied. Methods: From 2007-2019, we reviewed MM patients treated with triplet/quadruplet therapy in our institution to assess the incidence of primary refractory disease and the impact of salvage therapies in this population. Primary refractory disease was defined as either progressive disease or stable disease at 4-6 cycles. The Kaplan-Meier estimates were used for survival probabilities. PFS and OS were calculated from MM diagnosis to progression, escalation/change of treatment, or death, respectively. For the primary refractory group, the second PFS and second OS were measured from the start of second-line therapy. The Cox regression model was used for multivariable analysis with the following variables (age, ISS, induction therapy, FISH, and bone marrow plasma cells at diagnosis). Results: We identified 1127 patients, of which 1086 were evaluated for hematologic response after 4-6 cycles. Of these, 93.3% (1013) had evidence of response, while 6.7% (73) had primary refractory disease. With a median OS of 50.7 months, patients with primary refractory disease had an increased risk for shorter survival in univariable and multivariable analysis (HR: 3.6, 95% CI = 2.61 – 4.96, HR = 3.89, 95% CI = 2.68 – 5.65, respectively). In subgroup analysis of primary refractory patients, the median second PFS and second OS from the first relapse were 11.9 months (95% CI: 8.7 – 17.3 months) and 43.4 (95% CI: 31.4– 75.9 months), respectively. Patients that received 2nd line ASCT had increased second PFS (20.9 vs. 8.1 months, respectively, p < 0.01) and second OS (74.7 vs. 31.3 months, respectively, p = 0.02) compared to patients that did not. Patients that took daratumumab as the second line did not have any significant survival differences compared to those who did not, p = NS. Conclusions: We conclude that early progression remains a significant factor for shorter OS in the current era, and salvage ASCT could be the most beneficial option for this population. [Table: see text]

8043 Background: Extramedullary Multiple Myeloma (EMM) has an aggressive clinical course and can present at diagnosis [primary EMM, (pEMM)] or relapse [secondary EMM, (sEMM)]. Here, we report clinical characteristics and outcomes of EMM, and predictive factors for the development of sEMM. Methods: We identified 299 patients with biopsy-proven EMM between 01/01/2000 and 12/31/2021. Patients with solitary plasmacytomas, paraskeletal MM and primary plasma cell leukemia were excluded. A 1:1 matched pair analysis (matched for year of diagnosis of MM for comparable follow-up and treatment eras) was performed to compare clinical characteristics and outcomes for patients with and without sEMM. Results: The median follow-up from the diagnosis of MM was 11.5 years (95%CI: 9.3-14.8). Of 299 patients, 204 (68%) patients had sEMM and 95 (32%) had pEMM, with largely comparable baseline characteristics (Table). The median overall survival (OS) from the diagnosis of sEMM was 0.7 (95% CI: 0.6-0.9) years compared to 3.6 (95%CI: 2.4-5.6) years for pEMM (p<0.0001). For sEMM, mutlvariable analysis (MVA) for OS identified visceral organ involvement (eg. liver, lung/pleura, brain, pancreas, etc.) to be associated with inferior OS [HR 1.6 (95% CI: 1.1-2.4), p=0.01]; high-risk cytogenetics (HR-CTG), ISS-3 stage, and age did not impact OS from sEMM. For pEMM, HR-CTG [HR 2.3 (95% CI 1.1 -4.8), p=0.03] and ISS-3 stage [HR 3.1 (95% CI 1.5-6.7), p=0.003] were associated with inferior OS on MVA whereas visceral EMM or age did not impact OS from pEMM. On univariate analysis, patients with sEMM were younger (median age 58.7 vs 61 years, p=0.006), had a higher proportion of 1q duplication (32% vs 17%, p=0.001), t(4;14) [16% vs 9%, p=0.047] and elevated LDH (30% vs 19%, p=0.04), compared to the matched cohort of patients without sEMM. On MVA, younger age at diagnosis, t(4;14) and 1q duplication at diagnosis of MM were independent predictors of development of sEMM. The median OS from diagnosis of MM was 5.4 years (95%CI: 4.1-6.2) for patients with sEMM versus 7.5 years (95% CI: 6.4-10.1; p <0.001) for the matched cohort. Secondary EMM was an independent poor prognostic marker for OS from the diagnosis of MM [HR 1.6 (95%CI: 1.2-2.1); p=0.004] in addition to age, ISS3 disease and HR-CTG. Conclusions: Outcomes of patients with EMM, especially sEMM, remain dismal. Patients with sEMM have higher rates of 1q duplication and t(4;14) at diagnosis of MM and carried an independent adverse prognosis in a matched cohort. [Table: see text]

8037 Background: Both daratumumab in combination with lenalidomide and dexamethasone (DRd) and bortezomib in combination with lenalidomide and dexamethasone (VRd) are endorsed by NCCN guidelines as preferred regimens for the treatment of transplant-ineligible (TIE) patients with newly diagnosed multiple myeloma (NDMM). DRd and VRd have each demonstrated superior efficacy relative to lenalidomide and dexamethasone (Rd) alone in the MAIA and SWOG S0777 trials, respectively, but have not been compared directly in a head-to-head trial. Naive comparisons of efficacy across the 2 trials may be biased because MAIA enrolled only TIE patients (median age 73 years), whereas S0777 enrolled a mixed transplant-not-intended (TNI) population, which included both TIE patients and patients choosing to defer/refuse frontline stem cell transplantation (median age 63 years). Methods: The present study leveraged individual patient-level data (IPD) from both trials to perform an anchored indirect treatment comparison of DRd vs VRd, adjusting for differences in trial eligibility criteria and baseline patient characteristics. Harmonized inclusion criteria (NDMM, age ≥65 years, ECOG performance status ≤2) were applied to both trial populations. Age ≥65 years served as a proxy for TIE status since S0777 enrolled a mixed TNI population. Propensity score (PS) reweighting was used to balance the 2 trial populations on key baseline prognostic factors including age, sex, ISS stage, ECOG performance status, hemoglobin, eGFR, lactate dehydrogenase (LDH) level, and cytogenetic risk. Missing data were addressed with multiple imputation. After alignment of inclusion criteria and PS reweighting, an anchored indirect comparison was performed wherein within-trial progression-free survival (PFS) hazard ratios (HRs) for DRd vs Rd and VRd vs Rd were estimated and used to make indirect inference about PFS for DRd vs VRd. Results: 727 MAIA participants and 198 S0777 participants were eligible for inclusion. After PS reweighting, the trial populations were balanced on the key baseline prognostic factors identified above (standardized difference < 0.1 for each). The adjusted PFS HRs were 0.53 (95% CI: 0.41–0.68; P< 0.0001) for DRd vs Rd in MAIA and 0.88 (0.63–1.23; P= 0.46) for VRd vs Rd in S0777. In the adjusted Rd-anchored indirect comparison, the PFS HR for DRd vs VRd was 0.60 (0.39–0.90; P= 0.02). Conclusions: In this adjusted indirect treatment comparison based on IPD from the MAIA and S0777 trials, PFS was significantly longer for DRd relative to VRd. In the absence of a head-to-head trial comparing DRd and VRd, the present study may help to inform treatment selection in TIE patients with NDMM.

8032 Background: Patients (pts) with TCE RRMM have few treatment (Tx) options and poor HRQoL. Ide-cel, the first in class CAR T cell Tx for pts with TCE RRMM, improved PFS versus standard (std) regimens in the KarMMa-3 trial. We report the PRO results comparing the Tx arms. PROs provide further understanding of Tx benefit of ide-cel from the pts’ perspective. Methods: KarMMa-3 (NCT03651128) is an open-label phase 3 RCT comparing the efficacy and safety of ide-cel with std regimens in pts with TCE RRMM, who had received 2–4 prior regimens. In addition to clinical endpoints, we evaluated the impact of ide-cel compared with std regimens on the changes in HRQoL, measured by the EORTC QLQ-C30, EORTC QLQ-MY20, and the EQ-5D-5L questionnaires. PROs were collected at baseline (screening), day of infusion and monthly from 2–24 months (mo) and thereafter every 3 mo. This interim analysis reports PROs through 20 mo. Comparisons were performed on least squares mean (LSM) changes from baseline over time between arms using constrained longitudinal data analysis (cLDA). Results: In total, 386 pts were randomized (ide-cel, 254; std regimens, 132). PRO compliance was high over time ( > 80%). At baseline, PROs were similar between arms. LSM changes from baseline to 20 mo showed significant differences ( P < 0.05), with effect sizes of 0.3–0.7, in favor of ide-cel for most domains, including global health status/QoL, cognitive functioning, fatigue, and pain (EORTC QLQ-C30); side effects of Tx (EORTC QLQ-MY20); and the EQ-5D-5L VAS. The difference in overall LSM change reached or exceeded the pre-specified between-groups minimal importance difference (MID) for improvement in most domains in favor of ide-cel (Table). Conclusions: Ide-cel showed statistically significant and clinically meaningful improvements in HRQoL, including key MM symptoms and functioning, for pts with TCE RRMM compared with std regimens. The PRO data for ide-cel expands upon the clinical outcomes observed in the KarMMa-3 trial. Clinical trial information: NCT03651128 . [Table: see text]

8024 Background: Minimal residual disease (MRD) is prognostic for survival in multiple myeloma (MM). MRD is usually assessed in the bone marrow (BM) by flow cytometry or NGS. MRD by FDG PET/CT provides a global representation of the tumor burden, including response assessment of extramedullary disease. We examined MRD status in MM pts using both BM and PET/CT at Mayo Clinic. Methods: Medical records were reviewed retrospectively for MM pts who received CAR-T between 4/2018 and 12/2022. All PET/CT scans were assessed by radiologists. BM MRD was assessed by flow cytometry with a sensitivity of 10-5. Progression-free survival (PFS) and overall survival (OS) were analyzed by Kaplan-Meier method. Results: Among the 157 CAR-T pts, including 89 pts who received FDA-approved CAR-T, median age was 63 years, 59% (92/157) were males, 42% (66/157) had high risk cytogenetics with median of 5 prior lines of therapy, 36% (57/157) had plasmacytoma. Incidence of CRS was 83%, 5% grade ≥ 3 CRS. Incidence of ICANS was 19%, 4% grade ≥ 3 ICANS. CR/sCR rate was 37%. One hundred and thirty-seven pts (87%) had evaluable BM at month (mo) 1, 85% (117/137) were BM MRDneg at mo 1. Baseline demographics were comparable between the two groups except age, % BM plasma cells and use of bridging therapy. Among the MRDneg pts, CR/sCR rate was 44% (51/117) and 95% (111/117) had sFLC below normal. At median follow-up of 13.8 months, median PFS among pts with BM MRDneg at 1 mo was 12 mo (95% CI: 11, 30) vs 3 mo (95%CI: 2, 7) for BM MRDpos (p<0.001). Median OS among pts with BM MRDneg at 1 mo was 34 mo (95% CI: 24, NR) vs 22 mo (95%CI: 7, NA) for BM MRDpos (p<0.01). At month 1, 112 pts had both BM and PET/CT assessments available, 64/112(57%) were both BM MRDneg/PET MRDneg, 38/112 (34%) were MRDneg for either BM or PET and 10/112 (9%) were positive for both BM and PET (MRDpos/PET MRDpos). Baseline demographics except age were comparable between the 2 groups (Table). Rate of conversion from MRDpos to MRDneg was low. Rate of sustained BM and PET MRDneg at mo 12 was 44% (8/18). The median PFS and OS for BM MRDneg/PET MRDneg was significantly longer as compared to others (Table). Conclusions: Achieving FLC below normal, BM MRDneg and PET MRDneg at 1 month, regardless of IMWG response at that time, is prognostic for both PFS and OS in MM pts receiving CAR-T. Failure to achieve any of these confers poor prognosis. [Table: see text]