Long-term Responders Research Articles

55P Long-term responders (LTR) with niraparib maintenance in platinum-sensitive recurrent high-grade serous ovarian cancer (PSROC) focusing on subsequent therapies and post-progression outcomes (GEICO-88R study)

55P Long-term responders (LTR) with niraparib maintenance in platinum-sensitive recurrent high-grade serous ovarian cancer (PSROC) focusing on subsequent therapies and post-progression outcomes (GEICO-88R study)

Outcomes following long-term response to immune checkpoint inhibitors in patients with advanced melanoma.

9520 Background: Immune checkpoint inhibitors (ICI) targeting PD-1 and CTLA-4 can achieve durable responses. Historically, therapies in advanced malignancies were considered palliative, however long-term results from ICI melanoma studies suggest cure may be possible for some patients (pts). Despite clinical trial data, little is known about the risk, character, and clinical outcome of late recurrences after ICI. Methods: ICI treated pts with advanced melanoma who had a long-term disease control, defined as not requiring a subsequent line of systemic therapy within 3 years, were retrospectively identified at 11 centres. Those who had progressive disease managed with local therapies were included if no new systemic therapy was commenced within the 3 years. Demographics, disease characteristics, treatment, toxicity, recurrence patterns, management and outcomes were collected. Results: 567 pts were identified, with a median follow up of 7 years since start of therapy. At ICI commencement, 41% and 17% had M1c or M1d disease respectively, 26% had an elevated LDH, 33% were BRAF mutant and 24% had received prior therapy. The ICIs received were anti-PD-1 +/- an investigational agent (59.3%), anti-PD-1 plus anti-CTLA-4 (35.8%), or an anti-CTLA-4 (5%). The median duration of therapy was 18 months, with 31% of pts stopping due to toxicity. 63 pts (11.1%) had oligo-progression within 3 years from ICI start. 53 pts (9.3%) had progression after 3 years, with median time to progression of 16.3 months. Subsequent late progression was more common in those who had oligo-progression within 3 years of treatment compared to those who had not (14/63, 22% vs 39/504, 7.7%, P<0.001). The risk of late progression was lower in those who achieved a complete response (CR) compared to those without a CR (23/369, 6.2% vs 30/198, 15.2%, P<0.001). The landmark 5 year PFS was 95% compared to 89% in those with or without a CR respectively. Duration of therapy, treatment cessation due to toxicity, or corticosteroid use were not associated with the risk of late progression. Most late progression occurred within year 3 to 5 (38/53, 72%). 15 pts who progressed after 3 years were managed with local therapy alone. In progressors retreated with PD-1 alone as the next subsequent therapy, 14 of 26 (54%) responded (7 CR, 7 PR). In the total cohort, there were 31 (5.5%) deaths, 7 (1.2%) from melanoma. Of the pts with a CR, 14 (3.7%) died, only 1 (0.3%) from melanoma. Of the 53 pts who progressed after 3 years, 10 (19%) died, 7 (13%) from melanoma. Conclusions: In this population of pts with advanced melanoma with long term disease control from ICI, the risk of subsequent disease progression and death was low (1.2%). Predictors for late progression after 3 years were a non-CR best response and prior progression within 3 years. This and other data suggest a significant proportion of long-term ICI responders are likely cured, and may inform frequency and duration of follow up.

A phase II trial of olaparib and durvalumab in patients with recurrent IDH-mutated gliomas.

2013 Background: Isocitrate dehydrogenase mutations (IDHmt) define astrocytomas and oligodendrogliomas. IDHmt results in accumulation of R-2-hydroxyglutarate (2HG), leading to epigenetic dysregulation and defective homologous recombination repair, providing a rationale for poly (adenosine 5’-diphophate-ribose) polymerase (PARP) inhibitors. PARP inhibition upregulates PD-L1 so the combination with immune checkpoint inhibition is potentially synergistic. Methods: Patients (pts) with recurrent high-grade IDHmt gliomas were enrolled in this phase II open-label study (NCT03991832). Eligibility included progressive disease with up to 2 prior lines of systemic therapies and ECOG 0–1. Pts received olaparib 300 mg twice daily continuously and durvalumab 1500 mg IV every 4 weeks. Simon’s optimal two-stage design was used. The primary objective was overall response rate (ORR) and disease control rate (DCR) by RANO criteria. Secondary objectives included overall survival (OS), progression free survival (PFS) and safety.Exploratory biomarkers of response and resistance were assessed with serial blood samples using cell-free methylated DNA immunoprecipitation and high-throughput sequencing (cfMeDIP-seq) as well as multiplex-immunohistochemistry. Results: In the 29 pts enrolled between January 2020–February 2023, median age was 40.5 (range 23–66) and 41% were female. Initial tumor grade was 2 in 9, 3 in 8 and 4 in 12 pts, respectively. Median time to enrollment from tumour diagnosis was 5.9 years. All had prior resection and median number of prior systemic therapies was 2. One patient clinically deteriorated before starting treatment. ORR was 10%, 95% CI 2.2–27%, with responses in 3 pts. One pt with grade 4 astrocytoma had a complete response and remains on treatment after 33 months. The other 2 responders with grade 4 astrocytoma had response durations of 4.1 and 9.8 months. DCR was 28% (95% CI 12.7–47.2%) with 5 additional pts demonstrating stable disease. With a median follow-up of 33 months, mOS was 9.5 months (95% CI 4.3–19.3) and mPFS was 1.9 months (95% CI 1.8–3.0). There was no treatment-related grade 3–4 toxicities. Any grade toxicities included fatigue (48%), nausea (17%), diarrhea (10%), and cytopenias (3%). Using serial cfMeDIP-seq, cell free DNA methylomes comparing responders versus progressors using the top differentially methylated regions can predict treatment response with high accuracy (AUC 0.833). Post progression, differentially methylated genes converge on TGF-β and signal transduction pathways, suggesting possible mechanisms of resistance. Multi-modal analysis of long-term responders will additionally be presented. Conclusions: Combination treatment with olaparib and durvalumab for pts with IDHmt glioma is well tolerated but has limited efficacy in unselected pts. cfMeDIP-seq can reliably predict tumour progression providing a blood-based biomarker of treatment response. Clinical trial information: NCT03991832 .

Non-Small Cell Lung Cancer Metastatic Without Oncogenic Alterations.

This overview provides a thorough review of current treatment approaches for first-line management of nononcogenic addicted non-small cell lung cancer. We also address pertinent clinical decision-making queries encountered in everyday practice, such as the optimal treatment strategy for PD-L1-high patients, predictive factors for response to immune checkpoint inhibitors (ICI) both in terms of patient and cancer characteristics, the potential benefits of dual checkpoint blockade, and the unresolved issue of safe discontinuation strategies for long-term responders. Around one in five patients falls into this latter category while the majority develop either primary or acquired resistance to ICI-based first-line therapy, necessitating effective subsequent lines of treatment. Docetaxel, with or without combination of antiangiogenic agents, serves as the backbone of treatment, although evidence in the post-ICI setting is limited. Given that an inflamed tumor microenvironment (TME) is crucial for ICI responses, targeting the TME in cases of acquired resistance alongside continued ICI administration appears rational, although clinical trials so far have failed to confirm this hypothesis. Antibody-drug conjugates have emerged as a promising treatment modality, offering the potential for reduced toxicity and improved efficacy by targeting specific cancer antigens. Moreover, several chemotherapy-free approaches are currently under investigation for treatment-naïve patients, including alternative ICI and drugs targeting epitopes on both cancer and immune cells.

Multiple myeloma patients with a long remission after autologous hematopoietic stem cell transplantation

Autologous stem cell transplantation (autoHCT) is considered standard of care for newly diagnosed multiple myeloma (MM). Although most patients eventually progress after autoHCT, a small proportion achieve a durable response. In this retrospective study we included 1576 patients, 244 (15%) of whom were long-term responders (LTR), defined as having a progression-free survival (PFS) of ≥8 years after transplant. Patients in the LTR group were younger than the non-LTR group (median age 58.4 vs. 59.5 years; p = 0.012), less likely to have high-risk cytogenetics (4% vs. 14%; p < 0.001), more often had <50% bone marrow plasma cells (67% vs. 58%; p = 0.018) and R-ISS stage I disease (43% vs. 34%). More patients in the LTR group received post-transplant maintenance (63% vs. 52%; p = 0.002). Patients in the LTR group had higher rates of complete response (CR) at day100 (41% vs. 27%; p < 0.001) and at best post-transplant response (70% vs. 37%; p < 0.001), compared to the non-LTR group. Patients in the LTR groups had a median PFS of 169.3 months and the median overall survival (OS) had not been reached. The leading cause of death in the LTR was disease progression. In conclusion, 15% of patients in the cohort were LTR after upfront autoHCT, with distinct characteristics and a median PFS of more than 14 years.

Abstract PO2-04-01: Predictors of exceptional response to first line HER2-targeted therapy for metastatic breast cancer

Abstract Background HER2-targeted therapies have transformed the trajectory of HER2-positive (HER2+) metastatic breast cancer (MBC), with a subgroup of responders remaining on first line (1L) therapy for many years (yrs). Despite these promising outcomes, the paradigm remains palliative, with some patients (pts) receiving therapy indefinitely. Opportunities to interrupt therapy are controversial and anecdotal in the setting of a limited understanding of long-term responders and lack of predictive biomarkers. Methods We identified prevalent pts with HER2+ MBC seen and consented at Dana-Farber Cancer Institute between 2010 and 2023, regardless of the original date of MBC diagnosis. Exceptional responders (ExRes) were pts without evidence of progressive disease (PD) 3 yrs from initiation of 1L therapy for MBC. Conventional responders (ConRes) were pts who experienced PD within 3 yrs of 1L treatment initiation. We compared clinicopathological characteristics and treatment patterns between ExRes and ConRes using Chi-square or Wilcoxon test. We analyzed median time to treatment switch due to PD (TTS-PD) – i.e., time from metastatic diagnosis to 1L treatment end due to PD - and overall survival, via the Kaplan-Meier method and with a landmark analysis at year 3 (Y3). Our primary aim was to identify predictors of exceptional response to 1L anti-HER2 therapy. Results Of 635 pts with HER2+ MBC, we identified 147 ExRes and 370 ConRes and excluded 118 pts due to follow up ≤ 3 yrs and no PD events. Median follow up was 7.1 yrs (IQR 5.5-11.0) for ExRes and 7.1 yrs (IQR 4.0-11.4) for ConRes. Median age at MBC diagnosis was 50.7 yrs (range 21.9-91.9) for ExRes and 49.8 yrs (26.9-82.3) for ConRes. ExRes presented more often with de novo MBC than ConRes (52.1 vs 30.6%, p&amp;lt; 0.0001). On metastatic samples, more ExRes than ConRes had HER2 3+ tumors by immunohistochemistry (IHC) (93.7 vs 81.0%, p=0.002), whereas the proportion of ER-positive disease was similar between the two groups (45.6 vs 53.4%, p=0.1). Most pts received (neo)adjuvant anti-HER2 agents in both groups (62.5 vs 72.7%, p=0.1). More ExRes than ConRes (55.8 vs 42.7% p=0.007) received 1L chemotherapy (CT) plus trastuzumab (H)/pertuzumab (P). Alternative 1L treatments were CT plus H (26.5 vs 25.7%), H +/- P +/- endocrine therapy (8.2 vs 10.5%), T-DM1 (2 vs 9.2%), tyrosine kinase inhibitors-based regimens (7.5 vs 10.8%). For pts with recurrent MBC, disease-free interval was longer for ExRes than ConRes (median 4.7 vs 3.4 yrs, p=0.01). Visceral involvement at MBC relapse was similar for ExRes and ConRes (78.2 vs 77.8%, p=0.9). Brain metastases at any timepoint were less frequent among ExRes than ConRes (42.9 vs 55.1%, p=0.01). Among ExRes, 70 (47.6%) pts experienced PD after Y3, with a median TTS-PD of 4.6 (4.1-5.1) yrs. In a landmark analysis at Y3, the 2-year TTS-PD was 68.5% (95% CI: 59.8%-75.7%) (5 yrs from treatment start), and 4-year overall survival was 86.5% (95% CI: 78.1%-91.9%) (7 yrs from treatment start). ConRes received a median of 5 (1-19) treatment regimens for MBC, with a median 1L TTS-PD of 12 (10.8-13) mo. A total of 89 (60.5%) ExRes and 214 (57.8%) ConRes underwent tumor sequencing. Data comparing genomic features between ExRes and ConRes will be presented. Conclusions In this prospective cohort, 28% of pts with HER2+ MBC had exceptional response to 1L anti-HER2 therapy. Consistent with prior data, ExRes present more frequently with de novo disease and HER2 IHC 3+ tumors. In our cohort, ExRes had a median follow-up of 7.1 years and 52.4% never experienced PD. Although a significant proportion of pts with HER2+ MBC derive long-term benefit from anti-HER2 therapy, the treatment paradigm remains palliative, and it is unknown whether biomarkers may reliably predict exceptional response and guide future treatment. Ongoing work will explore whether genomic features vary between ExRes and ConRes. Citation Format: Stefania Morganti, Tianyu Li, Katheryn Santos, Melissa Hughes, Nolan Priedigkeit, Yvonne Li, Marla Lipsyc-Sharf, Gregory Kirkner, Janet Files, Julie Kasparian, Elizabeth Grant, Gunjan Gupta, Giuseppe Curigliano, Sara Tolaney, Andrew Cherniack, Nabihah Tayob, Nancy Lin, Heather Parsons. Predictors of exceptional response to first line HER2-targeted therapy for metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-04-01.

Pulmonary Arterial Hypertension (PAH) Group 1 (Part A): Overview, Classification, Clinical Subsets, and Workup

Abstract: Pulmonary hypertension is a rare, progressive disease characterized by increased pulmonary arterial pressure and right ventricular failure due to pulmonary vascular remodeling. The disease definition and management have evolved over time. The 6th WSPH now defines it as a mean pulmonary arterial pressure &gt;20mmHg, while recent ESC/ERS guidelines recommend lowering the threshold for pulmonary vascular resistance to 2WU. : Understanding of the disease has improved through registries, classifying it into five distinct groups with similar histology, pathophysiology, and therapeutic approaches. These groups include PAH, with heritable and idiopathic causes, as well as various clinical subsets involving connective tissue disease, HIV, portopulmonary hypertension, congenital heart disease, and schistosomiasis. Long-term responders to calcium channel blockers, PAH with venous/capillaries involvement, and persistent PH of newborns are categorized under Group 1, now re-classified as IPAH. : A comprehensive workup for suspected patients includes various tests like electrocardiogram, pulmonary function testing, autoimmune workup, HIV testing, echocardiogram, right heart catheterization, and cardiopulmonary exercise testing. : This review emphasizes the disease's definition and epidemiology, delving into each subset and providing updated workup guidelines. The subsequent article will focus on risk stratification and treatment strategies.

COLUMBUS 7-year update: A randomized, open-label, phase III trial of encorafenib plus binimetinib versus vemurafenib or encorafenib in patients with BRAF V600E/K-mutant melanoma

BackgroundTreatment with encorafenib plus binimetinib and encorafenib monotherapy is associated with improved progression-free survival (PFS) and overall survival (OS) compared with vemurafenib in patients with BRAF V600E/K-mutant metastatic melanoma. We report results from the 7-year analysis of COLUMBUS part 1 (NCT01909453) at 99.7 months (median duration between randomization and data cutoff). Methods577 patients with locally advanced unresectable or metastatic BRAF V600E/K-mutant melanoma who were treatment-naive or progressed after first-line immunotherapy were randomized 1:1:1 to encorafenib 450 mg once daily (QD) plus binimetinib 45 mg twice daily (BID) (n = 192), vemurafenib 960 mg BID (n = 191), or encorafenib monotherapy 300 mg QD (n = 194). No prior BRAF/MEK inhibitor was allowed. ResultsSeven-year PFS and OS rates (95 % CI) were 21.2 % (14.7–28.4 %) and 27.4 % (21.2–33.9%) in the encorafenib plus binimetinib arm and 6.4 % (2.1–14.0 %) and 18.2 % (12.8–24.3 %) in the vemurafenib arm, respectively. Median melanoma-specific survival (95 % CI) was 36.8 months (27.7–51.5 months) in the encorafenib plus binimetinib arm and 19.3 months (14.8–25.9 months) in the vemurafenib arm. Thirty-four long-term responders (complete/partial response ongoing at 7 years) were identified across arms. ConclusionsThis is the longest follow-up from a phase III trial of BRAF/MEK inhibitor combination in BRAF V600E/K-mutant metastatic melanoma. Safety results were consistent with the known tolerability profile of encorafenib plus binimetinib. Results support the long-term efficacy and known safety of encorafenib plus binimetinib in this population and provide new insights on long-term responders. Interactive data visualization is available at the COLUMBUS dashboard (https://clinical-trials.dimensions.ai/columbus7/).

Positive Vasoreactivity Testing in Pulmonary Arterial Hypertension: Therapeutic Consequences, Treatment Patterns, and Outcomes in the Modern Management Era.

Among patients with pulmonary arterial hypertension (PAH), acute vasoreactivity testing during right heart catheterization may identify acute vasoresponders, for whom treatment with high-dose calcium channel blockers (CCBs) is recommended. However, long-term outcomes in the current era remain largely unknown. We sought to evaluate the implications of acute vasoreactivity response for long-term response to CCBs and other outcomes. Patients diagnosed with PAH between January 1999 and December 2018 at 15 pulmonary hypertension centers were included and analyzed retrospectively. In accordance with current guidelines, acute vasoreactivity response was defined by a decrease of mean pulmonary artery pressure by ≥10 mm Hg to reach <40 mm Hg, without a decrease in cardiac output. Long-term response to CCBs was defined as alive with unchanged initial CCB therapy with or without other initial PAH therapy and World Health Organization functional class I/II and/or low European Society of Cardiology/European Respiratory Society risk status at 12 months after initiation of CCBs. Patients were followed for up to 5 years; clinical measures, outcome, and subsequent treatment patterns were captured. Of 3702 patients undergoing right heart catheterization for PAH diagnosis, 2051 had idiopathic, heritable, or drug-induced PAH, of whom 1904 (92.8%) underwent acute vasoreactivity testing. A total of 162 patients fulfilled acute vasoreactivity response criteria and received an initial CCB alone (n=123) or in combination with another PAH therapy (n=39). The median follow-up time was 60.0 months (interquartile range, 30.8-60.0), during which overall survival was 86.7%. At 12 months, 53.2% remained on CCB monotherapy, 14.7% on initial CCB plus another initial PAH therapy, and the remaining patients had the CCB withdrawn and/or PAH therapy added. CCB long-term response was found in 54.3% of patients. Five-year survival was 98.5% in long-term responders versus 73.0% in nonresponders. In addition to established vasodilator responder criteria, pulmonary artery compliance at acute vasoreactivity testing, low risk status and NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels at early follow-up correlated with long-term response and predicted survival. Our data display heterogeneity within the group of vasoresponders, with a large subset failing to show a sustained satisfactory clinical response to CCBs. This highlights the necessity for comprehensive reassessment during early follow-up. The use of pulmonary artery compliance in addition to current measures may better identify those likely to have a good long-term response.

Long-Term Effects of a 6-Week Power-Based Resistance Training and Fast Walking Interval Training Program on Physical Function, Muscle Power, Disability, and Frailty in Pre-Frail and Frail Older Adults

Introduction: Concurrent training has been shown to be a beneficial approach to improve overall health status in older adults. However, little is known about the adaptations of this type of training in the long term (i.e., after cessation of exercise), even less in older people affected by frailty syndrome. Therefore, this study aimed (i) to assess the effects of a 6-week concurrent training program composed of power-oriented resistance training and fast walking interval training on physical function, muscle power, disability in activities of daily living and frailty in pre-frail and frail older people, and (ii) to assess the effects of a 6-month detraining period on these outcomes. Methods: A total of 59 pre-frail and frail older adults (>75 years old; Frailty Phenotype >1) were allocated into intervention (INT; n = 32; 81.8 years; 21 women) or control (CON; n = 27; 82.5 years; 19 women) groups. Primary outcomes of this study were Short Physical Performance Battery (SPPB), relative sit-to-stand (STS) power, Barthel index, Lawton scale and Frailty Phenotype. Assessments were performed at baseline (PRE), after the concurrent training programme (POST) and after 6 months of follow-up (DET) in both groups. Mixed model repeated measures ANOVA with Bonferroni’s post hoc tests was used. Results: Immediately after the intervention (∆ = POST-PRE), INT improved SPPB (∆ = 3.0 points; p < 0.001), relative STS power (∆ = 0.87 W·kg−1; p < 0.001) and reduced their frailty levels (∆ = −1.42 criteria; p < 0.001), while no changes were observed in CON. After 6 months of detraining (∆ = DET-PRE), INT showed higher SPPB (∆ = 2.2 points; p < 0.001), higher relative STS power (∆ = 0.73 W·kg−1; p < 0.001) and lower frailty (∆ = −1.24 criteria; p < 0.001) values than those reported at baseline, which were significantly different than those reported by CON. Both, Barthel index and Lawton scale values were not modified during the study in either group. Conclusions: The 6-week concurrent training program improved physical function, muscle power and reduced frailty in pre-frail and frail older people and these improvements were maintained above baseline levels after 6 months of detraining. However, due to the individual variability found, future studies of long-term responders versus non-responders in frail populations are required.

88 Long-Term Responders to first-line single agent immunotherapy in advanced Non-Small Cell Lung Cancer. Real-world evidence from The Christie.

88 Long-Term Responders to first-line single agent immunotherapy in advanced Non-Small Cell Lung Cancer. Real-world evidence from The Christie.

Five-Year Follow-Up of POLARIS-01 Phase II Trial: Toripalimab as Salvage Monotherapy in Chinese Patients With Advanced Melanoma.

To investigate the efficacy and toxicity after long-term follow-up of anti-PD-1 antibody in advanced melanoma with predominantly acral and mucosal subtypes. In the POLARIS-01 phase II trial, 128 Chinese patients with advanced melanoma refractory to standard therapy received toripalimab until disease progression or unacceptable toxicity for ≤2 years. For those who progressed after discontinuation due to 2-year treatment completion, rechallenge was allowed. The primary objectives were safety and overall response rate (ORR). As of February 8, 2021, ORR was 17.3% (95% CI: 11.2-25.0) evaluated by the independent radiologic review committee. The median overall survival (OS) for patients with known melanoma subtypes was 16.3 m for acral, 41.5 m for nonacral cutaneous, and 10.3 m for mucosal melanoma. Thereafter, the evaluation was continued by investigators. As of November 4, 2022, 5 years after the last enrollment, median duration of response was 15.6 months (range, 3.7-64.5+), median progression-free survival (PFS) was 3.5 months (95% CI, 2.2-5.3), and 60-month OS rate was 28.5% (95% CI: 20.2-37.2). Thirteen patients completed a 2-year treatment of toripalimab, with the subtypes of acral (2/13), non-acral cutaneous (4/13), mucosal (3/13) and unknown primary (4/13). Five patients were rechallenged. Four of them, all of whom were non-mucosal, completed the rechallenge course of 2 years with PFS ≥ 24 months. This is the largest prospective anti-PD-1 trial with mature data in advanced melanoma in China. Toripalimab demonstrated a manageable safety profile and durable clinical response in Chinese patients with metastatic melanoma who had failed in standard therapy. Immunotherapy seems less efficacious for long-term responders with mucosal primaries as rechallenge therapy.

Clinical significance of vasoreactivity in patients with pulmonary arterial hypertension: a new glance

Long-term responders for calcium channel blocker (CCB) therapy represent the minority population among the patients with idiopathic/hereditary/drug-induced pulmonary arterial hypertension (PAH). The frequency of vasoreactive testing (VRT) has been dramatically decreased over the past decade in clinical practice, while the amount of PAH specific therapy prescription has been raised substantially. Current review highlights the frequency of VRT in the modern population of patients with idiopathic PAH. Interconnections between pulmonary vascular morphology, physiology and genetics in long-term responders for CCB therapy and patients with negative VRT are analyzed. Pulmonary vasoreactive reserve prognostic value discussed.

Abstract 1747: The mutational landscape and its longitudinal dynamics in relapsed and refractory Hodgkin lymphoma

Abstract Introduction: In classical Hodgkin-lymphoma (cHL), only a few cases recur, and only a limited fraction of patients is primary-refractory to standard-polychemotherapy. Underlying genomic features of unfavorable clinical courses remain sparsely characterized. Here, we investigated the genomic characteristics of primary-refractory/relapsed cHL in contrast with long-term-responders (LTR). Methods: Therefore, ultra-deep next-generation panel-sequencing was performed on a total of 59 samples (20 LTR, 26 relapsed (rHL: 11 initial-diagnosis, 15 relapse) and 13 primary-refractory (prHL: 8 initial-diagnosis, 5 progression) from 44 cHL-patients applying a hybrid-capture approach. We compared samples associated with distinct disease courses concerning their oncogenic drivers, mutational signatures, and perturbed pathways. Results: Compared to LTRs, mutations in genes such as PMS2, PDGFRB, KAT6A, EPHB1, and HGF were detected more frequently in prHL/rHL. Additionally, we observed that in rHL or prHL, BARD1-mutations occur, whereas ETV1, NF1, and MET-mutations were eliminated through clonal selection. A significant enrichment of non-synonymous variants was detected in prHL compared to LTRs and a significant selection process in favor of NOTCH-pathway mutations driving rHL or prHL was observed. Conclusion: This study delineates distinct mutational signatures between LTR and rHL/prHL, whilst illustrating longitudinal dynamics in mutational profiles using paired samples. Further, several exploitable therapeutic vulnerabilities for rHL and prHL were identified. Citation Format: Hanno Witte, Axel Künstner, Thomas Hahn, Veronica Bernard, Stephanie Stoelting, Kathrin Kusch, Kumar Nagarathinam, Nikolas von Bubnoff, Cyrus Khandanpour, Arthur Bauer, Michael Grunert, Annette Arndt, Konrad Steinestel, Hartmut Merz, Hauke Busch, Alfred Feller, Niklas Gebauer. The mutational landscape and its longitudinal dynamics in relapsed and refractory Hodgkin lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1747.

Abstract 6391: Spatial proteomic profiling unveils pre-existing anti-tumor immunity as a hallmark of exceptional benefit from immunotherapy in NSCLC

Abstract Background: Immunotherapy is firmly established as a treatment regimen in various solid tumors due to its exceptional benefits observed in a select group of patients. Despite widespread use of immune checkpoint blockade (ICB) across diverse solid tumors, including non-small cell lung cancer (NSCLC), the quest for a clinically informative biomarker for long-term benefit remains unmet. Here we investigate the potential utility of clinicopathological and spatial proteomic profiling of tumor specimens from NSCLC patients to identify predictive biomarkers of long-term benefit to ICB. Methods: Forty-nine patients diagnosed with advanced NSCLC who received ICB at Hospital del Mar, Barcelona between 2017-2021 were included. Long-term responders (LTR, n=21) were defined as patients achieving a maintained radiologic response for more than 2 years, and short-term responders (STR, n=28) as patients presenting disease progression within the first six months of ICB initiation. Clinicopathological information, incidence of immune related adverse (irAES) and PD-L1 tumor proportion score assessed by IHC was available for all of them. DSP GeoMx was performed in subset of patients (LTR n=14 and STR n=14), to assess 49 immune biomarkers. Pancytokeratin (panCK; epithelial), CD3, CD20 and SYTO 13 (nuclear) were utilized as morphology biomarkers. Regions of interest were placed in tissue areas containing tumor and segmented in Tumor (PanCK+) and tumor microenvironment (TME) (PanCK-) that was used on downstream analysis. Digital counts were normalized using the protein expression of housekeeper proteins. Statistical analysis was performed using linear mixed models. A P value less than 0.05 was considered significant. Results: Our analysis revealed specific characteristics of LTR patients compared with STR, namely LTR population was enriched for PD-L1 positive in tumors (p=0.005) and a higher incidence of immune-related adverse events (irAEs) (p=0.001). Within the Tumor compartment, LTR patients displayed significantly higher levels of IDO1, CD8, PD-L1, CD45, HLA-DR and STING, while STR patients exhibit higher levels of B7-H3, CD56 and OX40L (p&amp;lt;0.05 for all proteins). Comparison analysis of the TME compartment between LTR and STR revealed augmented levels of IDO1, CD8, CD45, CD11c, CD27 and CD3 in LTR patients, and lower levels of B7H3 and OX40L compared with STR patients (p&amp;lt;0.05 for all proteins). Conclusions: Our comprehensive analysis of metastatic NSCLC patients treated with ICB has unveiled distinct clinicopathological and immunological features associated with long-term benefit of ICB, highlighting the presence of pre-existing antitumor immunity as a stronger predictor of long-term benefit. These findings offer insights into potential biomarkers and therapeutic strategies for enhancing ICB outcomes in metastatic NSCLC. Citation Format: Sharia Hernandez, Rafael Bach, Mario Giner, Wei Lu, Larisa Kostousov, Sean Barnes, Khaja Khan, Laura Masfarré, Xavier Villanueva, Ignacio Sanchéz, Nil Navarro, Álvaro Taus, Miguel Galindo, Max Hardy, Raúl Del Rey-Vergara, Albert Iñañez, Beatriz Sanchez-Espiridion, Laura Moliner, Sergi Clavé, Beatriz Bellosillo, Ana Rovira, Júlia Perera-Bel, Ignacio Wistuba, Edurne Arriola, Luisa M. Solis, Pedro Rocha. Spatial proteomic profiling unveils pre-existing anti-tumor immunity as a hallmark of exceptional benefit from immunotherapy in NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6391.

Abstract 6436: Tumor-educated platelets for therapy stratification of metastasized castration resistant prostate cancer (CRPC)

Abstract One in ten men diagnosed with prostate cancer will have metastases. At some point the metastases becomes castration therapy resistant, contributing leading to the high mortality of prostate cancer. Novel androgen directed treatments, like abiraterone and enzalutamide, have made substantial difference to therapy response, yet only within subgroups of CRPC patients. Correct therapy stratification may prolong the life of the patients, possibly turning a deadly disease into a more chronic disease. For this to happen we need predictive biomarkers that can be used to longitudinally follow the disease in order to identify vulnerabilities and to monitor acquired resistance, e.g. we need to develop personalized liquid biopsy platforms. Using the platelet enriched fraction of a blood sample we here show that we can use the platelets ability to sequester material during circulation to provide information derived from the tumor, a.k.a. tumor-educated platelets. This information could be used as a companion diagnostic to identify patients that will respond to therapy, and to longitudinally monitor tumor progression. In this study, a previously published three gene profile, plt3G profile, was validated in a larger cohort (n=97) and showed that combined analysis of the three genes transcripts (KLK3, FOLH1, NPY) could be used to identify long-term responders regarding progression-free survival after enzalutamide (n=47; PFS; LR p&amp;lt;0,001, HR 0,32, p&amp;lt;0,001) or abiraterone (n=50; PFS; LR p=0.007, HR 0.45, p=0,009) -treatment. Furthermore, progression and resistance development could be accurately longitudinal followed. The plt3G profile showed a significant overlap with circulating tumor DNA (ctDNA) biomarkers, but in addition also provided predictive information around treatment response. Tumor-educated platelets provide therapy-predictive biomarkers as well as biomarkers for longitudinal monitoring of disease progression and resistance development, which ultimately could provide information for therapy switching. Their easy accessibility makes tumor-educated platelets an attractive biosource to be used alone or in combination others, to enable a fluid biomarker platform with the aim to turn a lethal cancer disease into a more chronic disease. Citation Format: Jonas A. Nilsson, Marie Lundholm, Lee-Ann Tjon-Kon-Fat, Linda Köhn, Camilla Thellenberg-Karlsson, Andreas Josefsson, Pernilla Wikström. Tumor-educated platelets for therapy stratification of metastasized castration resistant prostate cancer (CRPC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6436.

What patients with advanced cancer experience as helpful in navigating their life with a long-term response: a qualitative study

PurposeDespite improved survival for people with advanced cancer due to new medical treatments, a growing group of long-term responders (LTRs) has to learn to live with uncertainties that affect several life domains. At the core of their experience, they neither feel like a patient nor feel healthy. Despite growing awareness of LTRs’ experiences, learning more about how they cope with their long-term response can provide insight into how to best support them. Our study aimed to gain a deeper understanding what LTRs experience as helpful in navigating life with a long-term response.MethodsWe conducted an exploratory qualitative study using thematic data analysis. Semi-structured in-depth interviews were conducted with 17 participants with advanced melanoma or lung cancer with confirmed response or long-term stable disease while on immuno- or targeted therapy.ResultsLTRs reported several strategies to navigate life with a long-term response, for example, by involving the social environment, seeing uncertainty as an opportunity, and being present in the moment. This helped them to reclaim a sense of control, alter their perspective, and reshape their lives according to their values.ConclusionUsing different coping strategies enables LTRs to acknowledge both their sick and healthy side. Striking a healthy balance between being oriented on feeling sick or feeling healthy can help LTRs and their close others to navigate life with a long-term response. Healthcare professionals can provide support by recognizing whether LTRs are oriented at feeling sick or healthy, and by actively involving close others during medical appointments.

Regorafenib plus nivolumab in unresectable hepatocellular carcinoma: the phase 2 RENOBATE trial

Regorafenib has anti-tumor activity in patients with unresectable hepatocellular carcinoma (uHCC) with potential immunomodulatory effects, suggesting that its combination with immune checkpoint inhibitor may have clinically meaningful benefits in patients with uHCC. The multicenter, single-arm, phase 2 RENOBATE trial tested regorafenib–nivolumab as front-line treatment for uHCC. Forty-two patients received nivolumab 480 mg every 4 weeks and regorafenib 80 mg daily (3-weeks-on/1-week-off schedule). The primary endpoint was the investigator-assessed objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. The secondary endpoints included safety, progression-free survival (PFS) and overall survival (OS). ORR per RECIST version 1.1 was 31.0%, meeting the primary endpoint. The most common adverse events were palmar-plantar erythrodysesthesia syndrome (38.1%), alopecia (26.2%) and skin rash (23.8%). Median PFS was 7.38 months. The 1-year OS rate was 80.5%, and the median OS was not reached. Exploratory single-cell RNA sequencing analyses of peripheral blood mononuclear cells showed that long-term responders exhibited T cell receptor repertoire diversification, enrichment of genes representing immunotherapy responsiveness in MKI67+ proliferating CD8+ T cells and a higher probability of M1-directed monocyte polarization. Our data support further clinical development of the regorafenib–nivolumab combination as front-line treatment for uHCC and provide preliminary insights on immune biomarkers of response. ClinicalTrials.gov identifier: NCT04310709.

Clinical characteristics of patients treated with immune checkpoint inhibitors in EGFR-mutant non-small cell lung cancer: CS-Lung-003 prospective observational registry study

PurposeImmune checkpoint inhibitors (ICIs) are ineffective against epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). This study aimed to investigate the clinical characteristics of patients who were treated or not treated with ICIs, and of those who benefit from immunotherapy in EGFR-mutant NSCLC.MethodsWe analyzed patients with unresectable stage III/IV or recurrent NSCLC harboring EGFR mutations using a prospective umbrella-type lung cancer registry (CS-Lung-003).ResultsA total of 303 patients who met the eligibility criteria were analyzed. The median age was 69 years; 116 patients were male, 289 had adenocarcinoma, 273 had major mutations, and 67 were treated with ICIs. The duration of EGFR-TKI treatment was longer in the Non-ICI group than in the ICI group (17.1 vs. 12.7 months, p < 0.001). Patients who received ICIs for more than 6 months were categorized into the durable clinical benefit (DCB) group (24 patients), and those who received ICIs for less than 6 months into the Non-DCB group (43 patients). The overall survival in the DCB group exhibited longer than the Non-DCB group (69.3 vs. 47.1 months), and an equivalent compared to that in the Non-ICI group (69.3 vs. 68.9 months). Multivariate analysis for time to next treatment (TTNT) of ICIs showed that a poor PS was associated with a shorter TTNT [hazard ratio (HR) 3.309; p < 0.001]. Patients who were treated with ICIs and chemotherapy combination were associated with a longer TTNT (HR 0.389; p = 0.003). In addition, minor EGFR mutation was associated with a long TTNT (HR 0.450; p = 0.046).ConclusionICIs were administered to only 22% of patients with EGFR-mutated lung cancer, and they had shorter TTNT of EGFR-TKI compared to other patients. ICI treatment should be avoided in EGFR mutated lung cancer with poor PS but can be considered for lung cancer with EGFR minor mutations. Pathological biomarker to predict long-term responders to ICI are needed.

Long-Term Responders after Upfront Autologous Hematopoietic Stem Cell Transplant for Multiple Myeloma

Long-Term Responders after Upfront Autologous Hematopoietic Stem Cell Transplant for Multiple Myeloma