Citations

TPS7570 Background: Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin lymphoma (NHL), and although > 50% of pts achieve long-term remission with first-line therapy, pts with R/R disease as well as those with R/R grade 3b follicular lymphoma (FL), double-, or triple-hit high-grade lymphomas have poor long-term outcomes (Crump 2017; Kahl 2016; Jain 2012). Autologous (auto) chimeric antigen receptor (CAR) T cell therapy has provided additional options for pts with R/R disease, but only when leukapheresis and manufacturing prove feasible (Jacobson 2020). Allogeneic (allo) CAR-T cells were designed specifically to address these unmet needs by using healthy donor T cells to produce a readily available product and remove the need for bridging chemotherapy. We are currently investigating the safety and efficacy of CTX110, an allo anti-CD19 CAR-T cell product modified by using CRISPR/Cas9-editing to disrupt the endogenous T-cell receptor (TCR) alpha constant (TRAC) locus in order to remove TCR expression and disrupt β2-microglobulin, which eliminates major histocompatibility complex (MHC) class I expression. Disruption of the TCR should significantly reduce or eliminate risks of graft-versus-host disease and elimination of MHC class I expression may increase CAR-T cell persistence by mitigating CTX110 rejection. In addition, the anti-CD19 CAR transgene construct is precisely inserted into the TRAC locus. Methods: The Phase 1 CARBON trial (NCT04035434) is an open-label, multicenter, global study evaluating the safety and efficacy of CTX110 in pts ≥18 y with R/R DLBCL NOS, double- or triple-hit DLBCL, or transformed or grade 3b FL with ≥2 prior lines of therapy or who are ineligible for/refused prior auto hematopoietic stem cell transplant (HSCT). Pts who received prior auto CAR-T or allo HSCT are excluded. Pts will receive lymphodepleting chemotherapy with fludarabine 30mg/m2 and cyclophosphamide 500mg/m2 for 3 days, followed by CTX110 infusion. In part A, dose escalation will be performed using a 3+3 design. Upon completion of dose finding, the cohort will be expanded to further assess safety signals and efficacy including the primary efficacy endpoint of overall response rate. Key secondary efficacy endpoints include duration of response, progression-free survival, and overall survival. The trial is currently open and enrolling. Clinical trial information: NCT04035434.

2537 Background: Orva-cel is a B-cell maturation antigen–targeted chimeric antigen receptor (CAR) T cell therapy being evaluated in the phase 1/2 EVOLVE study (NCT03430011) in pts with RRMM who had at least 3 prior lines of therapy (Tx). We previously reported safety and efficacy in the phase 1 study and established the recommended dose (RD) of orva-cel as 600 × 106 CAR+ T cells (Mailankody et al, ASCO 2020). Cytokine release syndrome (CRS), a dominant toxicity of CAR T cell therapy, is mediated in part by IL-1. We explore the role of ppx with AKR, an IL-1 signaling inhibitor, on reducing the incidence of grade (G) ≥2 CRS after orva-cel treatment at the RD. Methods: Fourteen pts were enrolled sequentially for AKR ppx and treated with orva-cel at the RD. The non-AKR ppx control group comprised the remainder of the phase 1 pts receiving orva-cel at the RD (n = 19). The median follow-up (range) was 3.0 mo (1.8–6.2) for the AKR ppx group and 8.8 mo (5.3–12.2) for the non-AKR ppx group. AKR was administered as 100 mg SC the night before orva-cel infusion, 3 h before the infusion (Day 1), and q24 h on Days 2–5. Dosing was increased to q12 h if CRS developed. CRS was graded by Lee (2014) criteria. Tocilizumab (T) and steroids (S) were used per protocol-specified treatment management guidelines. Results: Disease characteristics and outcomes are shown in the table. In AKR ppx and non-AKR ppx groups, median number of prior regimens was 6 and 5, and bridging Tx was used in 57% and 68% of pts, respectively. The total frequency of CRS was similar in the 2 groups, but with less G 2 in the AKR ppx pts; relative risk (95% CI) = 0.54 (0.21, 1.38). No G ≥3 CRS was seen in either group. The incidence of neurological events (NE), G ≥3 infection, and macrophage activation syndrome/hemophagocytic lymphohistiocytosis (MAS/HLH) was similar. T and S use was numerically lower with AKR ppx. Orva-cel expansion kinetics were similar in the 2 groups. All pts had a 2-month efficacy assessment, with ORR in 100% of AKR ppx and 95% of non–AKR ppx pts. Conclusions: In this nonrandomized evaluation of AKR ppx with orva-cel treatment, the incidence of G ≥2 CRS was lower in pts receiving AKR ppx. The use of AKR ppx produced no adverse effect on the incidence of NE, infection, or MAS/HLH, nor on orva-cel expansion or disease response. These results warrant further study of AKR ppx in CAR T cell therapy. Clinical trial information: NCT03430011. [Table: see text]

Abstract B-cell activation is increasingly linked to numerous fibrotic lung diseases, and it is well known that aggregates of lymphocytes form in the lung of many of these patients. Activation of B-cells by pattern recognition receptors (PRRs) drives the release of inflammatory cytokines, chemokines, and metalloproteases important in the pathophysiology of pulmonary fibrosis. However, the specific mechanisms of B-cell activation in patients with idiopathic pulmonary fibrosis (IPF) are poorly understood. Herein, we have demonstrated that B-cell activation by microbial antigens contributes to the inflammatory and profibrotic milieu seen in patients with IPF. B-cell stimulation by CpG and β-glucan via PRRs resulted in activation of mTOR-dependent and independent pathways. Moreover, we showed that the B-cell–secreted inflammatory milieu is specific to the inducing antigen and causes differential fibroblast migration and activation. B-cell responses to infectious agents and subsequent B-cell–mediated fibroblast activation are modifiable by antifibrotics, but each seems to exert a specific and different effect. These results suggest that, upon PRR activation by microbial antigens, B-cells can contribute to the inflammatory and fibrotic changes seen in patients with IPF, and antifibrotics are able to at least partially reverse these responses.

Abstract Background monarchE is a phase 3, open-label study evaluating abemaciclib combined with endocrine therapy (ET) compared to ET alone in patients with node positive, HR+, HER2-, high risk early breast cancer (EBC) that resulted in a statistically significant improvement in invasive disease-free survival (IDFS) at a pre-planned interim analysis. Following the positive interim analysis, patients continued to be followed for IDFS, distant recurrence, and overall survival. Methods After surgery and, as indicated, radiotherapy and/or chemotherapy, 5,637 patients with HR+, HER2-, high risk EBC were randomized (1:1) to standard of care adjuvant ET with or without abemaciclib (150 mg BD for 2 years). Patients with ≥4 positive nodes, or 1-3 nodes and either grade 3 disease, tumor size ≥5 cm, or central Ki-67 ≥20% were eligible. Here we present results of the primary outcome IDFS analysis which was planned after approximately 390 IDFS events. Results At the primary outcome analysis, median follow-up was approximately 19 months in both arms (an increase of 3.5 months from the interim analysis). A total of 1437 (25.5%) patients had completed the 2-year treatment period; 3281 (58.2%) were still in the 2-year treatment period. With 395 IDFS events observed in the intent-to-treat population, abemaciclib plus ET continued to demonstrate superior IDFS versus ET alone, with a 28.7% reduction in the risk of developing invasive disease (p=.0009; HR = 0.713; 95% CI = 0.583, 0.871). Two-year IDFS rates were 92.3% in the abemaciclib plus ET arm and 89.3% in the ET alone arm. There was a consistent benefit of abemaciclib in all prespecified subgroups. The addition of abemaciclib to ET also resulted in an improvement in distant relapse-free survival (DRFS). Overall survival was immature at the time of analysis. A key secondary endpoint was efficacy in patients with centrally assessed high Ki-67 (≥20%) (Ki-67H) (n=2498). Disease characteristics were well balanced between the arms of this population. Abemaciclib plus ET demonstrated superior IDFS vs ET alone, with a 30.9% reduction in risk of developing invasive disease (p=.0111; HR = 0.691; 95% CI = 0.519, 0.920) and 2-year IDFS rates of 91.6% and 87.1%, respectively. An improvement in DRFS treatment effect was also observed in the Ki-67H population. At the time of data cutoff, the median treatment duration of abemaciclib was 17.3 months and the median duration of ET was balanced between the arms (18.3 months in the abemaciclib arm and 18.7 months in the ET alone arm). Safety was consistent with the results at the interim IDFS analysis and with the known safety profile of abemaciclib. Conclusions At the primary outcome analysis, with a median follow-up of approximately 19 months, abemaciclib combined with ET continued to demonstrate a clinically meaningful improvement in IDFS in patients with HR+, HER2-, node-positive, high risk, EBC with a statistically significant improvement in IDFS in patients with central Ki-67 ≥20%. ClinicalTrials.gov: NCT03155997 Table 1: PrimaryOutcome EfficacyIntent-to-Treat PopulationIntent-to-Treat PopulationKi-67 ≥20% (Ki-67H) PopulationKi-67 ≥20% (Ki-67H) PopulationEndpointAbemaciclib + ET N=2808ET alone N=2829Abemaciclib + ET N=1262ET alone N=1236IDFS# events, n (%)163 (5.8)232 (8.2)82 (6.5)115 (9.3)log rank P value, HR (95% CI)p=.0009 0.713 (0.583, 0.871)p=.0111 0.691 (0.519, 0.920)Rate (%) at 2 years (95% CI)92.3 (90.9, 93.5)89.3 (87.7, 90.7)91.6 (89.4, 93.4)87.1 (84.3, 89.5)Difference (%) in 2-year rates (95% CI)3 (1.1, 5.0)4.5 (1.2, 7.7)DRFS# events, n (%)131 (4.7)193 (6.8)65 (5.2)102 (8.3)log rank P value, HR (95% CI)p=.0009 0.687 (0.551, 0.858)0.609 (0.445, 0.833)Rate (%) at 2 years (95% CI)93.8 (92.6, 94.9)90.8 (89.3, 92.1)93.6 (91.6, 95.1)88.5 (85.7, 90.7)Difference (%) in 2-year rates (95%CI)3 (1.2, 4.8)5.1 (2.1, 8.1) Citation Format: Joyce A. O'Shaughnessy, Stephen Johnston, Nadia Harbeck, Masakazu Toi, Young-Hyuck Im, Mattea Reinisch, Zhimin Shao, Pirkko Liisa Kellokumpu Lehtinen, Chiun-Sheng Huang, Alexey Tryakin, Matthew Goetz, Hope S Rugo, Elzbieta Senkus, Laura Testa, Michael Andersson, Kenji Tamura, Guenther G. Steger, Lucia Del Mastro, Joanne Cox, Tammy Forrester, Sarah Sherwood, Xuelin Li, Ran Wei, Miguel Martin, Priya Rastogi. Primary outcome analysis of invasive disease-free survival for monarchE: abemaciclib combined with adjuvant endocrine therapy for high risk early breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS1-01.

8521 Background: Several clinical and molecular prognostic factors (e.g, International Staging System [ISS] stage, plasma cell labeling index, genomic models) exist for multiple myeloma (MM). We hypothesized that exploiting gene signatures representative of oncogenic pathway deregulation (i.e., Ras, Myc, etc.), would improve MM prognostication and also aid with the identification of novel therapeutic targets. Methods: Using a discovery cohort (n=47) of patients with MM and corresponding gene expression data, we built upon current molecular risk-stratification and devised a Bayesian genomic (“metagene”) model for prognosis. We validated that model in an independent patient cohort (n=207). Finally, we incorporated ISS staging and clinical variables to construct a combined Clinico-Genomic Risk Stratification System. We further validated the combined model in a separate cohort (n=72), in a blinded manner. Results: Using gene signatures predictive of oncogenic pathway activation in the discovery cohort, we identified specific patterns (metagenes) of signaling pathway activation with prognostic relevance. In an independent validation cohort, this metagene-based model accurately predicted event free survival (EFS) independently of ISS (multivariate hazard ratio [HR] 3.4 for ISS stage, and 5.4 for the metagene model, p=0.002). Using multivariate risk modeling, we incorporated ISS staging and the metagene model into a Clinico-Genomic System and successfully stratified the validation cohort into three groups (low, intermediate, and high risk) with markedly different EFS (HR 4.2 for intermediate risk and 14.0 for high risk vs. the low risk cohort, p<0.0001). In an additional blinded validation, the Clinico-Genomic System again accurately predicted median overall survival (68.7 [low risk] vs 24.7 [intermediate risk] vs 18.7 months [high risk], p<0.0001); more accurately than either ISS or other reported genomic models. Conclusions: A combined Clinico-Genomic Risk Stratification System, building on patterns of oncogenic pathway activation and ISS staging system, improves upon current prognostic models in MM and identifies novel pathway targets for future therapeutic consideration. No significant financial relationships to disclose.

Background: Limb salvage of the proximal tibia can be difficult due to the growth potential of and functional demands of the pediatric patients. Multiple reconstruction techniques exist, however, the ideal form of reconstruction is yet to be elucidated. The purpose of the current study is to evaluate outcomes in patients with an intercalary resection of the proximal tibia reconstructed with an allograft with or without a free vascularized fibula flap (FVF). Methods: Seventeen pediatric patients (9 males, 8 females) underwent lower extremity limb salvage with the use of intercalary cadaveric allograft at a mean age of 12±4 years. The most common diagnoses were osteosarcoma (n=6) and Ewing sarcoma (n=6). Patients were reconstructed with an allograft alone (n=6) or supplemented with an FVF (n=11). Results: All surviving patients had at least 2 years of clinical follow-up, with the mean follow-up of 12±7 years. The mean time to union of the allograft was 11±4 months, with 6 patients requiring additional bone grafting. There was no difference in the need for an additional bone graft (odds ratio=1.14, P=1.0) between patients with an FVF and those without. Four patients underwent an amputation, all with an allograft alone, due to disease recurrence (n=2) and due to infection (n=2). As such, there was a higher 10-year overall limb-salvage rate when the allograft was combined with an FVF compared with an allograft alone (100% vs. 33%, P=0.001). At last follow-up, the mean Mankin and Musculoskeletal Tumor Society rating was 86%, with a higher mean score in patients reconstructed with an FVF (94% vs. 70%, P=0.002). Conclusion: Use of an intercalary allograft supplemented with an FVF to reconstruct the proximal tibia provides a durable means of reconstruction with an excellent functional outcome following oncologic proximal tibia resection in a pediatric population. Level of Evidence: Level III—therapeutic level.

Abstract Introduction Prior studies established that compliance during the early days of positive airway pressure (PAP) therapy predicts long-term adherence, which in turn relates to outcomes. However, patient impressions gathered immediately after PAP titration may be the earliest indication of adherence and could help focus efforts at improving compliance. The aim of this study was to examine whether a survey on PAP experience during polysomnography predicts adherence. Methods This prospective cohort study included PAP naïve adults with obstructive sleep apnea who had PAP titration during polysomnography and had 30 day adherence data available. Patients answered a pre-existing 5-question survey with dichotomous answers (yes/no) regarding their PAP experience (improved sleep, general discomfort, PAP related discomfort, mask discomfort, willingness to use PAP). Primary outcome was 30 day adherence (average time used per night, percent of nights used, percent of nights with &gt;4 hours use). Results We enrolled 47 patients (68% male) with average age of 62.4 years, body mass index 32.6 kg/m2, and apnea-hypopnea index 27.8/hr. Patients answered an average of 3.4±1.3 survey questions favorably. The number of favorable answers correlated with percent of nights used and percent of nights with &gt;4 hours use (P&lt;0.05). Patients with improved sleep during PAP titration had a greater percent of nights with &gt;4 hours use (82.4% vs 60.3%; P &lt;0.05). In addition, successful titration during polysomnography (less than 5 events per hour) correlated with improved adherence and less leak after 30 days. Conclusion Initial PAP titration experience influences future PAP adherence. Although there was a correlation between answers on our pre-existing questionnaire and outcomes, some questions did not contribute much for this use. We believe a next step would be to develop questions that help predict future usage and better guide therapy. Support None

1087 Background: OlympiAD (NCT02000622) demonstrated the benefit of olaparib over standard of care in patients (pts) with HER2-negative (HER2-) metastatic breast cancer (MBC) and germline BRCA mutations (gBRCAm). LUCY (NCT03286842) aimed to provide additional data on the real-world effectiveness and safety of olaparib monotherapy in this setting. Methods: This Phase IIIb, open-label, single-arm study of olaparib 300 mg twice-daily, enrolled pts with HER2- gBRCAm MBC who had received a taxane and/or anthracycline in the (neo)adjuvant/metastatic setting, and ≤2 lines of chemotherapy for MBC. Hormone receptor-positive (HR+) pts had progressed on prior endocrine therapy (ET), and further ET was considered unsuitable. Primary endpoint: investigator-defined progression-free survival (PFS). Secondary endpoints: overall survival, time to first subsequent therapy or death (TFST), and investigator-assessed clinical response rate (CRR). The interim analysis was planned after 160 PFS events. Results: From Oct 2018-Sept 2019, 252 pts were enrolled (160 sites, 15 countries; mean age 46.2 [range 22-75] years; 73.4% ECOG PS 0). Median total treatment duration: 7.9 months (mo; range 0.2-20.0). Median PFS: 8.1 mo (95% confidence interval [CI] 6.9, 8.7; 166 events [65.9%]). Clinical trial information: NCT03286842 . Median TFST: 9.7 mo (95% CI 8.7, 11.1). CRR: 48.6% (95% CI 42.2, 55.0). Adverse events (AEs) in >20% of pts (all grades): nausea, anemia, asthenia, vomiting, and fatigue. 24.6% of pts reported a grade ≥3 AE, including anemia (n=33 [13.1%]). 4.4% of pts had an AE leading to treatment discontinuation. Conclusions: Interim results in this real-world population of pts with HER2- gBRCAm MBC were consistent with the OlympiAD study, and support olaparib as a chemotherapy-free alternative treatment for pts with gBRCAm advanced BC. [Table: see text]

Abstract Chromosomal translocations involving the immunoglobulin heavy-chain (IgH) locus at 14q32 are genetic hallmarks of human multiple myeloma (MM) and are likely primary oncogenic events in myeloma transformation. Common recurrent translocation partner genes of IgH account for 40–50% of cases and these rearrangements result in the transcriptional dysregulation of various proto-oncogenes such as CCND1, CCND3, FGFR3/MMSET, c-MAF, MAFB, MUM 1(IRF-4), c-MYC and it is becoming clear that these dysregulated genes play important roles in the pathogenesis and the treatment outcome of MM. Although the frequency of other partner genes of IgH translocations may be rare (&lt;1%), it is possible that many genes not currently identified as translocation partners are functionally converged into several signal pathways and play important roles as well. Through global gene expression profiling (GEP) studies of a large population of newly diagnosed MM, we have recently reported that dysregulation of any one of the three D-type cyclins is seen in almost all newly diagnosed MM and most patients with high levels of CCND2 expression was highly correlated with expression of c-MAF, MAFB or FGFR3/MMSET. In order to identify novel translocation partner genes in MM we combined GEP and fluorescence in situ hybridization (FISH) analysis in a large population of newly diagnsoed myeloma. We investigated whether IGH-CCND2 and IGH-MAFA translocations are seen in patients exhibiting high levels of CCND2 expression but not expressing c-MAF, MAFB, or FGFR3/MMSET. We also looked for a breakpoint and targeted gene at a non-random breakpoint at the 11q23 locus in 20 MM patients with 11q23 abnormalities detected by conventional G-banding. Here we report evidence of an IGH-CCND2 fusion in a newly diagnosed case of MM and an IGH-MAFA fusion in a newly diagnosed MM and an MGUS and also mapped the 11q23 breakpoint to within 100 kb in a newly diagnosed MM and a human myeloma cell line, NCU-MM-1 and identified an IGL Pou2AF1 fusion in the NCU-MM-1 line. Importantly these translcoatios do not involve the MLL or ATM genes. These three genes were all highly expressed as detected by GEP or quantitive RT-PCR in the samples in which these genes were translocated to IG loci. Although the frequency of these 3 translocations are very rare, they further the concept of a critical role of CCND2 expression in myelomegenesis and identifed the transcriptional coactivator Pou2AF1, which specifically associates with either OCT1 or OCT2, in the B-cell response to antigens and required for the formation of germinal centers, as a potential new translocation target in myeloma. Finally, our strategy of combining GEP signatures and cytogenetic analyses appears to be a practical means of identifying new IG- mediated translocations in myeloma.