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]

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]

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]

8013 Background: Ide-cel is an FDA-approved treatment for RRMM patients (pts). However, there is limited data on how BT for disease control during its manufacturing process affects clinical outcomes. Methods: Eleven US academic centers contributed data to this analysis without involvement from the manufacturer. By 5/1/2022, 235 pts had undergone leukapheresis, with 214 infused with a median follow up of 9 months (mos). BT was given between leukapheresis and CAR-T infusion. Results: In this analysis, 79% of pts (n = 170) received BT, which included alkylator-based in 35.5%, steroid and/or IMiD/Ab combos (IMiD combos) in 14%, PI combinations (PI combos) in 12%, and selinexor in 10%. BT recipients had higher ECOG PS 2-4, R-ISS 2-3, ferritin, and CRP before lymphodepleting (LD) chemo, however, no difference among BT subgroups. No difference in prior lines of therapy or penta-refractory between BT and No BT (NBT) groups or BT subgroups. Median cycle of the BT was 1 (1-7), with overall response rate (ORR) of 12%, with no difference among BT subgroups. Incidence and severity of CRS and ICANs were comparable in BT and NBT. However, pts who received BT had a longer median hospital stay compared to NBT, particularly in the alkylator/selinexor subgroups. There were no significant difference in cytopenias at day 90 post CAR-T between the BT and NBT or BT subgroups. For the 73% (n = 157) evaluable for day 90 response, there was no difference in the complete or ORR between the BT and NBT groups (41% vs. 52%; p = .2 and 84% vs. 87.5%, p = .8, respectively). Median PFS was worse at 8.1 mos in BT vs 11.5 mos in NBT (p = .03). Among BT subgroups, PFS was the longest with IMiD combos with median PFS not reached (NR), comparable to NBT, and was significantly longer than all other BT subgroups (p = 0.01). The median OS was 13.8 mos with BT and NR in NBT (p = .002). In BT subgroup analysis, alkylators had a shorter OS, although, this was not significant (p = .06). There was no significant difference in PFS and OS in relationship to response to BT (p = .6 and p = .9, respectively). Conclusions: Pts without BT had longer PFS and OS post ide-cel, likely reflective of less aggressive disease. Those who received BT with steroid/IMiD and Ab combos had similar PFS as NBT. However, BT choice is complicated by disease severity and should be evaluated per patient circumstances. [Table: see text]

8012 Background: Cilta-cel was FDA approved in 2022 for the treatment of RRMM. We evaluated the outcomes of patients treated with intended SOC cilta-cel. Methods: 12 US academic medical centers contributed data to this retrospective study. As of 12/31/2022, 177 patients were leukapheresed and 139 received cilta-cel. Results: The table describes the study population compared to the CARTITUDE-1 trial. More patients in our study had extramedullary disease (EMD, 35%) and high-risk cytogenetics (41%). 55% of the patients would not have met eligibility criteria for CARTITUDE-1. Common reasons for ineligibility were cytopenias (19%), prior BCMA therapy (14%), organ dysfunction (12%), oligosecretory disease (13%), and plasma cell leukemia (8%). 83% of the patients received bridging chemotherapy (overall response rate, ORR: 28%). Lymphodepletion included fludarabine (Flu) + cyclophosphamide (Cy): 81%, bendamustine: 11%, Cy: 4%, and cladribine + Cy: 4%. Median CAR-T cells infused were 0.6 million/kg (range: 0.1-0.9), and 19% of patients were treated on an expanded access protocol (EAP). Median follow-up was 2.3 months (range: 0-8). Cytokine release syndrome (CRS) was seen in 81% (≥ grade 3: 7%) and immune effector cell-associated neurotoxicity syndrome (ICANS) in 22% (≥ grade 3: 8%) of patients. Tocilizumab, steroids, and anakinra were used in 61%, 44%, and 10% of patients, respectively. Delayed neurotoxicity (NT) was seen in 9% (cranial nerve palsy: 8, Parkinsonism: 2, others: 3). Grade ≥ 3 cytopenias at day ≥ 30 were seen in 75% of patients. Infections were seen in 32% of patients. Day 30 (N=115) and best response rates (N=118) were: ≥ partial response (PR), 75/80%; ≥ very good PR, 44/62%; and ≥ complete response (CR), 26/40%, respectively. In the non-EAP FluCy population (N=88), best ORR/≥CR were 89/49%. 17 patients died by data cut-off, 4 due to disease progression and 13 (9%) due to non-relapse mortality (NRM) (grade 5 CRS: 3, infection: 6, CRS/infection: 1, grade 5 ICANS: 1, delayed NT: 2). Conclusions: Patients treated with intended SOC cilta-cel had a favorable ORR (80%) despite a larger proportion of patients having high-risk features relative to trial patients and limited follow-up. Response rates were higher in patients receiving conforming products with FluCy conditioning (89%). Delayed NT and NRM were seen in 9% of patients. Results will be updated with continued follow-up. D.K.H., K.K.P, M.J., Y.L. & S.S. contributed equally. [Table: see text]

8009 Background: Heavily pretreated patients (pts) with relapsed/refractory multiple myeloma (RRMM) treated with standard of care therapy have median overall survival (OS) of ~12 months (mo). In the single-arm, phase 1b/2 CARTITUDE-1 study (NCT03548207), pts received a single infusion of ciltacabtagene autoleucel (cilta-cel), a CAR-T cell therapy targeting BCMA. At the final protocol-specified analysis (27.7-mo median follow-up [MFU]), overall response rate (ORR) was 98%, with 83% stringent complete response (CR); 27-mo rates of progression-free survival (PFS) and OS were 55% and 70%, respectively. Here, we report study closeout results. Methods: Eligible pts received ≥3 prior lines of therapy (LOT) or were double refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD); and had received prior PI, IMiD, and anti-CD38 antibody therapy. Primary endpoint was ORR and safety; secondary endpoints included PFS, OS, and minimal residual disease (MRD) negativity at 10-5. Results: 97 pts received cilta-cel (median age 61 years [y]; median 6 prior LOT; 42% penta-drug refractory; 88% triple-class refractory; 99% refractory to last LOT). As of October 14, 2022, MFU was 33.4 mo (range, 1.5-45.2). Median (m) duration of response was 33.9 mo (95% CI, 25.5–not estimable [NE]). mPFS was 34.9 mo (95% CI, 25.2–NE), with an estimated 47.5% progression free and alive at 36 mo. mOS was not reached (NR), with an estimated 62.9% survival at 36 mo. Of 49 MRD-evaluable pts, 26 had MRD negativity sustained for ≥12 mo, of which 20 had sustained MRD-negative ≥CR. mPFS was NR in these subgroups (Table). 18 pts were MRD negative with ≥CR at 24 mo post infusion. No new safety signals and no new neurotoxicity events were reported since the 27.7-mo MFU. 6 new cases of second primary malignancy were reported, including 2 cases of basal cell carcinoma and 1 case each of myelodysplastic syndrome, B-cell lymphoma, melanoma, and prostate cancer. 5 additional deaths occurred (progressive disease [PD], n=3; pneumonia and sepsis, n=1 each [both unrelated to cilta-cel]), for a total of 35 (PD, n=17; unrelated to cilta-cel, n=12; related, n=6). Conclusions: Longer mPFS was observed after a single infusion of cilta-cel than any previously reported therapy in heavily pretreated pts with RRMM. Achieving CR and/or sustained MRD negativity was associated with prolonged PFS. Pts continue to be followed for safety and survival in the 15-y CARTINUE long-term study (NCT05201781; MMY4002). Clinical trial information: NCT03548207 . [Table: see text]

7509 Background: Axicabtagene ciloleucel (axi-cel) is an autologous CAR T approved for adult patients (pts) with r/r FL after ≥ 2 lines of systemic therapy. In the primary analysis of the pivotal ZUMA-5 trial, 94% of pts who received axi-cel to treat r/r FL achieved an objective response, with a 79% CR rate (Jacobson et al. 2022). Grade ≥ 3 cytokine release syndrome (CRS) and neurologic events occurred in 6% and 15% of pts, respectively. Here, we present the real-world outcomes of pts receiving axi-cel for r/r FL, including those who would have been ineligible for ZUMA-5. Methods: A total of 230 pts from 72 US centers receiving first axi-cel for r/r FL in the real-world setting between March 2021 and October 2022 were identified from the CIBMTR registry. The following pts were excluded: no consent, prior non-transplant cellular therapy, and FL grade 3b or 3a/3b unspecified. Of the 230 pts, 151 pts had post-infusion assessments and were included in the analysis of outcomes. Effectiveness outcomes were ORR, CR, DOR, PFS and OS. Adverse events included CRS, immune effector cell-associated neurotoxicity syndrome (ICANS) and prolonged cytopenia. Results: Of the 230 pts, median age was 62 years and 60% were male. Prior to infusion, 98% had an ECOG performance score of 0-1, 33% had elevated LDH, and 66% were chemo-resistant. Clinically significant comorbidities were present in 74% of the pts. Ninety-two (40%) pts would have been ineligible for ZUMA-5, mainly due to comorbidities. Pts had a median of 4 (range 1-13) lines of prior therapy including 14% who also underwent prior ASCT. Median time from leukapheresis to infusion was 28 days (IQR 26-34). 9% of pts received bridging therapy. Outcomes were analyzed among the 151 pts with follow-up (median 6.2 mo). ORR and CR rates were 93% (95% CI 88-97%) and 84% (95% CI 77-89%), respectively. Estimated PFS and OS at 6 mo were 88% (95% CI 81-92%) and 96% (95% CI 91-98%), respectively. Grade ≥ 3 CRS (ASTCT consensus) and ICANS (ASTCT consensus) occurred in 2% (95% CI 0-6%) and 13% (95% CI 8-19%) of pts, respectively. Median cumulative incidence estimates of CRS resolution was 5 days and ICANS resolution was 4 days. Among pts alive at Day 30 (n = 150), 11% experienced prolonged cytopenia (4% neutropenia, 9% thrombocytopenia). PFS and OS at 6 mo were comparable regardless of ZUMA-5 eligibility, while pts eligible for ZUMA-5 had fewer Grade ≥ 3 ICANS (10% vs 16%) and more rapid ICANS resolution (92% vs 71% resolved within 2 weeks). Pts aged ≥ 65 vs < 65 years had comparable effectiveness and safety profiles. Conclusions: This is the first report on axi-cel to treat r/r FL in real-world settings. Despite a broader pt population, early results demonstrate effectiveness and safety profiles consistent with those observed in the ZUMA-5 trial. The intent is to present findings from an updated dataset with longer follow-up at ASCO. Overall, these findings support the continued broad use of axi-cel to treat r/r FL.

TPS5634 Background: The prognosis for women with recurrent or persistent EC after progressing on first-line chemotherapy is poor, with a median overall survival (OS) of 12 months, highlighting the need for more efficacious therapies for this population. Immune checkpoint inhibitors either as monotherapy or when combined with kinase inhibitors have recently demonstrated encouraging response rates in pts with microsatellite instability-high (MSI-H)/mismatch repair-deficient (dMMR) and MS-stable (MSS)/MMR-proficient (MMRp) EC, respectively. Atezo is a humanized monoclonal anti-programmed cell death ligand 1 (PD-L1) inhibitor that has demonstrated monotherapy antitumor activity with an acceptable safety profile in relapsed recurrent EC. Atezo has shown compelling clinical efficacy for pts with certain solid tumors (e.g., urothelial, NSCLC, triple negative breast cancer) as monotherapy and as part of combinatorial therapy. The AFT-50 EndoMAP trial is a platform trial designed to evaluate the efficacy and safety of Atezo in combination with biomarker-defined targeted agents in pts with recurrent or persistent EC. Recognizing pts may have either progressed through or received a checkpoint inhibitor in a prior line of therapy, a non atezo cohort will also be open to enrollment. Methods: This is a phase IB/II non-randomized, multicenter, multicohort, biomarker-driven platform study consisting of two cohorts: A (atezo containing) and B (non atezo). Eligible pts have recurrent or persistent EC and have received no more than 2 prior lines of therapy. FoundationOne CDx (F1CDx) NGS assay will be used for genomic tumor profiling. In cohort A, pts may be eligible for one of the following doublets: Atezo+ipatasertib (PIK3CA/PTEN/AKT1-altered cancers), Atezo+talazoparib (tumors with genomic loss of heterozygosity (LOH) ≥16%), Atezo+Trastuzumab emtansine (ERBB2/HER2 mutated and/or amplified tumors), Atezo+Tiragolumab (MSI-H and/or TMB>10 mut/MB), and Atezo+bevacizumab (biomarker unmatched). Pts will receive Atezo in addition to the targeted agent (at the study approved dosing schedule) until progression, unacceptable toxicity, pt or physician decision to withdraw from the study, death, or study termination. Pts in cohort B, will be eligible for inavolisib (PIK3CA/PTEN/AKT1-altered cancers) + letrozole. Each cohort will enroll ~20 pts; however, the exact size of the cohort may be adjusted. The primary endpoint for Cohort A is confirmed overall response rate (ORR) for each cohort, and for Cohort B is progression free survival at 6 months. Secondary endpoints include disease control rate, duration of response, OS, safety and tolerability, 6-month PFS (cohort A). As a platform study, additional arms may be added, as supported by evolving understanding of EC and molecular targets. EndoMAP is actively enrolling at 17 sites in the US with a target of 25 sites nationwide. Clinical trial information: NCT04486352 .