Long-term Responders Research Articles

Clinical Characteristics and Pharmacokinetics Change of Long-Term Responders to Antiprogrammed Cell Death Protein 1 Inhibitor Among Patients With Advanced NSCLC

IntroductionImmune checkpoint inhibitors (ICIs) induce long-term, durable responses in patients with advanced NSCLC. Nevertheless, these responses are limited to a few patients, and most responders have disease progression. The purpose of this study was to determine the differences in clinical factors and blood drug concentrations between long-term responders (LTRs) and non-LTRs. MethodsWe retrospectively analyzed consecutive patients with advanced NSCLC who received antiprogrammed cell death protein 1 (PD-1) inhibitor monotherapy (nivolumab) from December 22, 2015, to May 31, 2017. Patients who obtained a clinical benefit for more than 6 months were referred to as “responders”; among these, individuals who had a durable response for more than 2 years were defined as “LTRs.” Those with a clinical benefit for less than 2 years were defined as “non-LTRs.” ResultsA total of 212 patients received anti–PD-1 inhibitor monotherapy. The responders accounted for 35% (75 of 212) of the patients. Of these, 29 (39%) were LTRs and 46 (61%) were non-LTRs. The overall response rate and median tumor shrinkage in the LTR group were significantly higher than those in the non-LTR group (76% versus 35%, p < 0.0001, and 66% versus 16%, p < 0.001, respectively). The groups had no significant difference in PD-L1 expression and serum drug concentration at 3- and 6-month post-treatment initiation. ConclusionsSignificant tumor shrinkage was associated with a long-term response to an anti–PD-1 inhibitor. Nevertheless, the PD-L1 expression level and pharmacokinetic profile of the inhibitor could not be used to predict the durable response among the responders.

Acute Vasoreactivity Testing and Outcomes in Pulmonary Arterial Hypertension: A Call for Increased Testing.

Pulmonary arterial hypertension (PAH) has a progressive, unremitting clinical course. Vasoreactivity testing (VdT) during right heart catheterisation (RHC) identifies a subgroup with excellent long-term response to calcium channel blockade (CCB). Reporting on these patients is limited. Established in 2011, the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) registry offers the opportunity to assess the frequency of VdT during RHC, treatment and follow up of PAH patients. Registry data from 3,972 PAH patients with index RHC revealed 1,194 VdT appropriate patients. Data was analysed in three groups: 1) VdT+CCB+: VdT positive, CCB treated; 2) VdT+CCB-: VdT positive, no CCB prescribed, 3) VdT-/noVdT: VdT negative, or VdT not tested. Data was reviewed for adherence to guidelines, clinical response (World Health Organization functional class [WHO FC], 6-minute-walk-distance [6MWD], RHC), and outcomes (survival or lung transplantation). Patients included had idiopathic (IPAH=1,087), heritable (HPAH=67) and drug or toxin-induced PAH (DPAH=40). A VdT was performed in 22% (268/1,194), with incomplete data in 26% (70/268); 28% (55/198) were VdT+. Analysis group allocation was: VdT+CCB+ (33/55), VdT+CCB- (22/55), VdT- (143)/noVdT (996). From patients with 1-year data VdT+CCB+ and VdT-/noVdT patients improved WHO FC, 6MWD and cardiac index (CI); VdT+CCB- data remained similar. Within the VdT+CCB+ group, 30% (10/33) were long-term CCB responders with a 100% 5-year survival; non-responders had a 61% survival at 5.4 years. Long-term responders were younger at diagnosis (40 yrs vs 54 yrs). Use of VdT testing and documentation is poor in this contemporary patient cohort. Nonetheless, survival inVdT+CCB+ patients from the PHSANZ registry is excellent, supporting guidelines promoting VdT testing. Strategies to promote the use of VdT are warranted.

Identification and external validation of clinical-molecular features to predict benefit from oxaliplatin reintroduction/rechallenge in patients with refractory metastatic colorectal cancer (mCRC).

153 Background: Oxaliplatin is a backbone cytotoxic treatment for mCRC patients, particularly in the front-line setting. In the refractory disease, current treatment options are scarce and with limited efficacy. Several retrospective studies have explored the efficacy of oxaliplatin reintroduction/rechallenge (OxRe) in this scenario. However, more evidence is still needed to determine which patients do benefit from this treatment strategy. Methods: The discovery cohort includes all patients treated with oxaliplatin in a third- or fourth-line setting at VHIO between 2015 and 2021 (N = 102). Results were externally validated in a real-world cohort of patients treated at community oncology practices from Oncoclínicas Group in Brazil (N = 157). We analyzed the impact of clinical-molecular features in uni- and multivariable prognostic models in terms of median progression free survival (mPFS) (discovery cohort) and median time to treatment discontinuation (mTTD) (validation cohort). For both cohorts separately, data was extracted from EHRs in structured formats (demographics, tumor characteristics, pharmacy records) and combined with elements from unstructured sources (physician notes on progression and survival status) using technology-based abstraction techniques. Results: In the discovery cohort, 102 out of 735 mCRC patients (13,9%) were eligible. Median oxaliplatin-free interval (from Oxl stop to OxRe) was 17 months (CI95% 13.0-23.2). In OxRe setting, mPFS was 4.0 months (CI95% 3.29-5.03). In PFS multivariate analysis, determinants of favorable outcome were left tumor location (p = 0.01), oxaliplatin-free interval (p = 0.03), administration of Bev in refractory setting (p = 0.001), and not receiving Bev in first-line treatment (p = 0.008). Overall, 27% of all patients had a mPFS &gt; 6 months with OxRe. In the validation cohort, out of 4,317 patients with mCRC, 157 (4%) were treated with OxRe. Median oxaliplatin-free interval was 15 months. Median time to treatment discontinuation (mTTD) of the OxRe was 3.4 months (CI95% 2.8-4.2). In multivariable model, the only independent prognostic factor was addition of Bev to OxRe (p = 0.036). Interestingly, 31% of all patients had mTTD &gt; 6 months, largely enriched (65%) in patients with first Bev exposure at the time of OxRe. Conclusions: This study suggests that in refractory mCRC patients re-exposed to oxaliplatin-based chemotherapy, the addition of Bev is associated with improved outcomes. One-third of the patients are long-term responders (PFS/TTD &gt; 6 months), reinforcing the value of this strategy in selected populations and the relevance of anti-angiogenic agents in refractory mCRC.

Clinical response to benralizumab can be predicted by combining clinical outcomes at 3 months with baseline characteristics.

Benralizumab is highly effective in many, but not all, patients with severe asthma. Baseline characteristics alone are insufficient to predict an individual's probability of long-term benralizumab response. The objectives of the present study were to: 1) study whether parameters at 3 months, in addition to baseline characteristics, contribute to the prediction of benralizumab response at 1 year; and 2) develop an easy-to-use prediction tool to assess an individual's probability of long-term response. We assessed the effect of benralizumab treatment in 192 patients from the Dutch severe asthma registry (RAPSODI). To investigate predictors of long-term benralizumab response (≥50% reduction in maintenance oral corticosteroid (OCS) dose or annual exacerbation frequency) we used logistic regression, including baseline characteristics and 3-month Asthma Control Questionnaire (ACQ-6) score and maintenance OCS dose. Benralizumab treatment significantly improved several clinical outcomes, and 144 (75%) patients were classified as long-term responders. Response prediction improved significantly when 3-month outcomes were added to a predictive model with baseline characteristics only (area under the receiver-operating characteristic (AUROC) 0.85 versus 0.72, p=0.001). Based on this model, a prediction tool using sex, prior biologic use, baseline blood eosinophils, forced expiratory volume in 1 s, and at 3 months OCS dose and ACQ-6 was developed which classified patients into three categories with increasing probability of long-term response (95% CI): 25% (3-65%), 67% (57-77%) and 97% (91-99%), respectively. In addition to baseline characteristics, treatment outcomes at 3 months contribute to the prediction of benralizumab response at 1 year in patients with severe eosinophilic asthma. Prediction tools as proposed in this study may help physicians optimise the use of costly biologics.

The Outcome of Discontinuing Tyrosine Kinase Inhibitors in Advanced Sarcoma Following a Favorable Tumor Response to Antiangiogenics Therapy.

(1) Background: The use of antiangiogenic TKIs (AA-TKIs) has recently emerged as a major paradigm shift in the treatment of advanced sarcoma. However, the feasibility of drug holidays for patients demonstrating a very favorable response remains unknown. (2) Methods: We aim to explore the outcomes of patients with advanced sarcoma who discontinued AA-TKIs after a (near-) complete remission or were long-term responders. Patients with advanced disease were included if they had bilateral or multiple lung metastases, extrapulmonary recurrence, a short disease-free interval, etc., at the initiation of AA-TKIs. (3) Results: A total of 22 patients with AA-TKI discontinuation were analyzed, with a median follow-up of 22.3 months post-discontinuation. Prior to discontinuation, there were four drug-induced complete remissions (CRs), twelve surgical CRs, and six long-term responders. Disease progression was observed in 17/22 (77.3%) patients, with a median of 4.2 months. However, since the majority were still sensitive to the original AA-TKIs and amenable to a second surgical remission, 7 out of these 17 patients achieved a second CR after disease progression and were thus considered as relapse-free post-discontinuation (pd-RFS). Therefore, the pd-RFS and post-discontinuation overall survival (pd-OS) in the last follow-up were 12/22 (54.5%) and 16/22 (72.7%), respectively. Remarkably, surgical CR and drug tapering off (versus abrupt stopping) were associated with a greater pd-RFS and pd-OS (p < 0.05). Furthermore, higher necrosis rates (p = 0.040) and lower neutrophil-to-lymphocyte ratios (NLR) (p = 0.060) before discontinuation tend to have a better pd-RFS. (4) Conclusions: Our results suggest that AA-TKI discontinuation with a taper-off strategy might be safe and feasible in highly selected patients with advanced sarcoma. Surgical CR, NLR, and tumor necrosis rates before discontinuation were potential biomarkers for AA-TKI withdrawal.

Living in the twilight zone: a qualitative study on the experiences of patients with advanced cancer obtaining long-term response to immunotherapy or targeted therapy

PurposeThe introduction of immunotherapy and targeted therapy has drastically improved the life expectancy of patients with advanced cancer. Despite improved survival, obtaining long-term response can be highly distressing and comes with uncertainties that affect several life domains. The aim of this study is to gain a deeper understanding of long-term responders’ lived experiences with obtaining long-term response to immunotherapy or targeted therapy.MethodsWe conducted an exploratory qualitative study using thematic data analysis. Semi-structured in-depth interviews were conducted with 17 patients with advanced melanoma or lung cancer who had a confirmed response to or long-term stable disease while on immunotherapy or targeted therapy.ResultsLong-term responders are living in a twilight zone, where they neither feel like a patient, nor feel healthy. This impacts their self-image, interactions with their social environment, and feelings of uncertainty. Due to their uncertain life perspective, long-term responders are going back and forth between hope and despair, while they are longing for their ‘old’ life, several barriers, such as protective behavior of the social environment, force them to adjust to a life with cancer.ConclusionLong-term responders are facing many challenges, such as searching for a renewed identity, dealing with ongoing uncertainty, and having to adapt to a new normal. This emphasizes the importance of providing this new patient group with tailored information and support.Implications for Cancer SurvivorsHealthcare professionals can support patients by normalizing their feelings and providing space for varying emotions. Using patient-tailored scan frequencies could help temper fear of progression.

Current and novel therapeutic strategies for optimizing immunotherapy outcomes in advanced non-small cell lung cancer.

During the past decade, immunotherapy has dramatically improved the outcomes of patients with non-small cell lung cancer (NSCLC). The development of specific antibodies against the programmed death (PD1) receptor and its ligand PD-L1 (programmed death ligand-1) has demonstrated substantial efficacy in advanced NSCLC either in the first or in the second line. However, the success of immune checkpoint inhibitors (ICIs) as monotherapy did not reach all patients and long-term responders still represent a small subset of cases. Under these circumstances, different strategies have been and are being tested to optimize clinical outcomes. Here, we reviewed the current evidence and the more promising perspectives of ICI combination approaches, such as the addition of chemotherapy, antiangiogenic agents, other co-inhibitory or co-stimulatory checkpoints, and targeted therapies.

Durable Response to CD19 CAR T Cell Therapy Is Associated with Cytotoxicity and Clonotypic Expansion of the Native T Cell Repertoire

Background: Axicabtagene ciloleucel (Axi-cel), a CD19 directed CAR T cell therapy, results in durable remission in a subset of patients with relapsed refractory large B cell lymphoma (LBCL) in the absence of persistent circulating CAR T cells. Aim: We postulated that long-term efficacy of CAR T therapy depends on the downstream triggering of native T cell immunity. To investigate this hypothesis, we performed single cell transcriptomic analysis of peripheral blood samples obtained at serial time points from patients participating in the ZUMA 1 Axi-cel study. We interrogated the T cell repertoire in patients who achieved durable remission compared to those experiencing disease relapse with respect to the expression of activated, cytotoxic, and inhibitory markers and clonotypic expansion of critical T cell subsets. Methods: Single cell immunoprofiling (expression + V(D)J sequencing) was performed using the 10x Genomics single cell 5' assay on PBMC samples from ZUMA-1 patients (N=32), collected at leukapheresis, 4 weeks, 6 months, and 12 months post Axi-cel. Based on clinical response, patients were divided into 3 groups: non-responders (N=8), relapsed within 1 year from CAR T infusion (N=9), and long-term responders (N=12). Three participants did not consent to the release of clinical outcomes. Results: A total of 405,775 cells passed quality check, capturing 73 cellular populations (Fig. 1a). T cells comprised the largest compartment with 28 different populations and 264,059 cells. Long-term responders demonstrated a distinct T cell landscape compared to relapsed patients, notable for a higher CD8/CD4 T cell ratio and increased expression of cytotoxic genes at all time points. Accordingly, activated CD8 cytotoxic effector memory T cell (Tem) populations were significantly increased in long-term responders compared to relapsed patients; especially two Tem populations, one characterized by high expression of CD44, GZMB and TGFB1 (Tem/TGFB1+), and a second highly expressing cytotoxic markers such as GZMA, GZMB, NKG7, CTS7, and CTSW (Tem/NKG7+). Following CAR T cell infusion, relapsed patients exhibited increased proportions of T regs and of T reg-like Th17 cells highly expressing FOXP3, IL2RA, and CTLA4. In contrast to all other CD4 populations, which were more abundant in the relapsed group, long-term responders presented higher abundance of CD4 cytotoxic T lymphocytes (CD4 CTL), characterized by high expression of both CD4-related and cytotoxic markers, including granzymes, and GNLY. Comparison of the TCR repertoire pre- and post-CAR T demonstrated a greater clonal expansion (TCRα/β-clonotype frequency > 1) of cytotoxic T cell populations in the long-term responders compared to relapsed and non-responder patients. In particular, higher clonotypic expansion was observed in the Tem/TGFB1+, Tem/NKG7+, and CD4 CTL populations (Fig. 1b). In contrast to our observations for the cytotoxic T cell populations, T regs were identified as more clonally expanded over time in the relapsed patients compared to the long-term responders. Conclusion: The application of single-cell immunoprofiling on longitudinal samples from CAR T cell treated LBCL patients from the ZUMA-1 trial demonstrated striking differences in cellular populations and clonal expansion patterns among patients who demonstrated long term remission compared to those who relapsed within 1 year following initial response. Reduced cytotoxic T cell expansion and increased proportions of immunomodulatory T cell populations were noted in relapsed patients compared to long term responders. These data provide insight into crucial factors that can be leveraged both to predict patient response and to further our understanding of long-term remission following CAR T cell treatment. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Discovery of Mutated ZNF208 Gene As a Novel Transcription Factor Exclusively Associated with Accelerated Phase and Blast Crisis Chronic Myeloid Leukemia: Hunt for Common Biomarker of Fatal CML Progression

Other Authors and their Affiliations: Muhammad Absar8, Tanveer Akhtar8, Masood Shammas9, Salman Basit10, Aamer Aleem11, Amer Mahmood11 1College of Applied Medical Sciences (CoAMS-A), King Saud Bin Abdulaziz University for Health Sciences / KAIMRC/ SSBMT, Al-Ahsa, Saudi Arabia; 8Hematology, Oncology and Pharmaco-genetic Engineering Sciences (HOPES) Group, Health Sciences Laboratories (HaSiL), Department of Zoology, Faculty of Biological Sciences, University of the Punajb, Lahore, Pakistan; 9Dana Farbar Cancer Institute, University of Harvard , Boston , United States of America; 10Centre for Genetics and Inherited Diseases, Taibah University, Madinah; 11College of Medicine, King Saud University, Riyadh, Saudi Arabia. #Corresponding author: Dr. Zafar Iqbal, drzafar.medgen1@gmail.com; iqbalz@ksau-hs.edu.sa Introduction: Chronic Myeloid Leukemia (CML) primarily develops as a result of t(22;9) that creates Philadelphia chromosome and oncogenic BCR-ABL fusion transcript (1). Discovery of BCR-ABL paved the way for designing signal transduction inhibitor drugs called tyrosine kinase inhibitors (TKIs) that have revolutionized CML treatment in 21st century, by making survival of CML equal to general population (2). Nevertheless, TKIs are minimally effective CML patients progressed to blast crisis (BC-CML). Unfortunately mechanism of CML progression is poorly understood (2). Various transcription factors (TFs) are associated with different diseases and progression of many cancers (3). Although a large number of TFs are involved in pathogenesis of acute leukemias, very little is known about role of TFs in CML progression. Therefore, objective of this study was to find about novel TFs associated with CML progression. Materials and Methods: Patient selection: The study subjects included accelerated phase (AP-CML) and blast crisis phase CML (BC-CML) patients (Experimental groups 1 & 2, respectively) while chronic phase treatment-naïve CML patients (CP-CML) were used as control 1, CP-CML CML long-term TKI responders (at least 3 continuous years of MMR) as control group 2 and TK-resistant CML patients as control group 3, along with healthy controls. Sample collection: DNA extraction and Clinical follow-up: 10 ml peripheral blood was collected from all study subjects. DNA was extracted and patient follow-up was carried out during course of this study. All treatment criteria per ENL guidelines were adopted. Whole Exome Sequencing (WES): WES was carried out using Illumina NGS instrument (HiSeq). bcl files were converted to fastq files by using bcl2fastqtool (4). Raw reads were aligned to genome using BWA tools while whole exome variants were annotated using Illumina Variant Studio (4). R package was employed to align specific TF-gene mutants to disease phenotypes (5). TF-genes mutated in all AP/BC-CML patients but not mutated in any of control groups were selected. Variants were confirmed using Sanger sequencing. Results: We found ZNF208 as a novel TF-gene mutated in all AP/BC-CML but in none of the controls (missense mutations G64A). It shows that mutated ZNF208 is a novel biomarker exclusively for advanced phases of CML. Discussion: ZNF208, a member of zing-finger binding transcription factor family, has been reported to be play role as tumor suppressor gene in various cancers through distant signaling pathways (3,6,7). Further studies are required to find exact role of ZNF208 in CML progression and its evaluation as potential biomarker and novel drug target in AP- and BC-CML. Conflict of interest: The authors declare that they have no conflict of interests.

Higher Rates of Severe Infection and Persistent Cytopenias in Long-Term CAR19 Responders Than after Autologous HCT: A Single Institution Study of 139 Subjects

Introduction: Chimeric antigen receptor (CAR) T-cell therapy is a leading treatment for relapsed or refractory aggressive and indolent lymphomas. One major adverse effect of CAR T-cell therapy is prolonged risk for infection. To quantify infectious risk after CAR, we performed a single center analysis of patients after anti-CD19 CAR T-cell therapy axicabtagene ciloleucel (axi-cel, n=78) and compared these with chemo-responsive lymphoma patients concurrently undergoing autologous hematopoietic cell transplant (HCT) with cyclophosphamide, carmustine, and etoposide conditioning (n=61). Methods: All 139 patients were treated between 09/2017 and 10/2021, with 37/78 CAR and 32/61 HCT patients treated after the first report of COVID-19 in California (02/2020). Median follow up was 718 days (range 175-1650 days). We included only patients without documented relapse of their lymphoma to avoid the confounding impact of lymphoma relapse on study endpoints. There was no significant difference in age or sex between groups. The CAR-treated cohort had fewer non-CAR prior lines of therapy (mean 3.0 vs mean 3.6, p=0.014, Wilcoxon rank sum test). Nearly all patients in the CAR group (76/78) were treated for large B-cell lymphoma (LBCL) entities, with 2/78 having follicular lymphoma with a prior LBCL history. Similarly, a minority of patients in the HCT group were treated for mantle cell lymphoma (4/61) and follicular lymphoma (5/61). Of the CAR patients 19/78 had an HCT prior to CAR, and 1/61 HCT patients had prior CAR treatment. For each patient we catalogued and graded post-treatment infections after day +30 (D+30) to focus on post-discharge events. Endpoints analyzed were any infection as well as severe infections (grade ≥3). Death and treatment for a second malignancy were considered competing events. We additionally catalogued blood count measurements including hemoglobin, platelets, white blood cell count (WBC), absolute neutrophil count (ANC) and absolute lymphocyte count (ALC) at regular intervals from pre-treatment through D+800. There was no difference in baseline WBC or ANC between groups. CAR-treated patients had a higher baseline ALC and hemoglobin while HCT-treated patients had higher baseline platelets (p<0.05 for all values, Wilcoxon rank sum test). Results: There was no difference in overall survival between groups (p=0.18, log-rank test). We performed cumulative risk regression considering infections for 1200 days starting at D+30. When considering all infections there was no significant difference in the total incidence of infections between the CAR and HCT group. However, there was increased risk in CAR-treated patients for severe (grade >= 3) infections (Figure 1A, HR 2.4, CI 1.2-4.78, Gray's p=0.013). The increased risk for severe infection was sustained when considering only infections that occurred greater than one-year post-transplant (HR 3.06, CI 1.14-8.21, Gray's p=0.021). The increased risk for severe infection in the CAR-treated cohort remained if patients with prior HCT were excluded, or if COVID-19 cases were excluded. We used linear mixed effects modeling to assess cytopenic risk longitudinally from D+28 to D+800. Age, sex, and non-CAR lines of therapy were also included in the multivariate model. CAR-treated patients demonstrated significantly reduced WBC, ANC, and ALC relative to patients treated with HCT (Figure 1B, p-value <5E-7, <0.05, and <5E-5 respectively, restricted maximum likelihood with t-test using Satterthwaite's approximation). These values remained significant if CAR patients with prior HCT were excluded from analysis. WBC and ANC were significantly reduced relative to pre-lymphodepletion baseline through D+365 (p<0.05, Wilcoxon signed-rank test). There was no difference in hemoglobin level in CAR-treated vs HCT patients using the same methods. Platelet counts in CAR-treated patients resolved to the same level as following HCT by the end of the follow up period. Conclusion: Lymphoma patients without relapse after axi-cel CAR T-cell therapy have greater risk for severe infections than a concurrent group of patients treated with autologous HCT. This risk is associated with prolonged reduction in WBC, ANC, and ALC but not platelets or hemoglobin. Clinical surveillance for infections in these immune compromised CAR-treated patients therefore remains critical, with role of additional prophylaxis strategies needing further investigation. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

High-Throughput DNA Sequencing Identifies a Novel Splice-Site Mutation in Fanconi Anemia Pathway Gene FANCD2 As a Potential Biomarker of Early and Late Phases of Disease Progression in Chronic Myeloid Leukemia

OtherAuthors: Muhammad Absar4, Tanveer Akhtar4, Masood Shammas8, Salman Basit9, Aamer Aleem10, Amer Mahmood10 8Dana Farbar Cancer Institute, University of Harvard , Boston USA, 9Centre for Genetics and Inherited Diseases, Taibah University, Madinah 10College of Medicine, King Saud University, Riyadh, Saudi Arabia. Introduction: Chronic Myeloid Leukemia (CML) results due to t(22;9) that leads to formation of Philadelphia chromosome and subsequently BCR-ABL fusion transcript, the later leading to leukemogenesis(1). This led to identification of tyrosine kinase inhibitors (TKIs) as novel drugs that revolutionised CML treatment in 21st century by improving the survival of CML equal to general population at least in developed countries (2). Nevertheless TKIs lose their effectiveness if CML patients progress to blast crisis (BC-CML). Despite extensive research in CML field, mechanism of its progression is still poorly understood and universal molecular biomarkers of CML progression are unknown (2). There are different mechanisms associated with initiation and progression of various cancers. DNA repair defects mediated through biologically very important Fanconi anemia (FA) pathway genes are associated with many cancers (3). Nevertheless, FA pathway genes have not been reported in myeloid malignancies. In this study, in searching for mutated genes associated with many mechanism, we hereby report mutations in a very important FA-pathway gene associated exclusively with CML progression for the first time in literature. Materials and Methods: Patient selection: Whole-exome sequencing (WES) was employed to find out mutations in novel TF-genes associated with accelerated phase (AP-CML) and blast crisis phase CML (BC-CML) patients (Experimental groups 1 & 2, respectively). Chronic phase treatment-naïve CML patients (CP-CML) were used as control 1, CP-CML CML long-term TKI responders (at least 3 continuous years of MMR) as control group 2 and TK-resistant CML patients as control group 3, along with healthy controls. Sample collection: DNA extraction and Clinical follow-up: 10 ml peripheral blood was collected from all study subjects. DNA was extracted and patient follow-up was carried out during course of this study. All treatment criteria per ENL guidelines were adopted. Whole Exome Sequencing (WES): WES was carried out using Illumina NGS instrument (HiSeq). bcl files were converted to fastq files by using bcl2fastqtool (4). Raw reads were aligned to genome using BWA tools while whole exome variants were annotated using Illumina Variant Studio (4). R package was employed to align gene mutants to disease phenotypes (5). DNA repair genes mutated in all AP/BC-CML patients but not mutated in any of control groups were selected. Variants were confirmed using Sanger sequencing. Results: A novel splice-site substitution (C2022T) in FANCD2 gene (that is a very important member of FA-pathway genes) was detected in all AP/BC-CML but in none of the controls. It shows that mutated FANCD2 can serve as a novel biomarker exclusively for advanced phases of CML. Discussion: It is the first report that a member of FA-pathway genes (FANCD2) has been reported mutated in progression of myeloid malignancies (6). It shows that DNA repair defects and genomic instability mediated through FA-pathway could be one of the important mechanisms in CML progression. Mutations in FANCD2 and such other genes could be reason why CML blast crisis patients have poor outcome of stem cell transplantation. Moreover, anti-cancer drugs targeting DNA repair defects (PARP inhibitors) like Olaparib in combination with TKIs could be effective in patients with mutated FANCD-2 and other such genes. Conflict of interest: The authors declare that they have no conflict of interests.

Clinical and Molecular Features of Highly Durable Response to Azacitidine+Venetoclax in Acute Myeloid Leukemia

Introduction: In older and/or unfit patients with newly diagnosed AML, the median duration of response to azacitidine+venetoclax (Aza/Ven) is 17.5 months. However, there is wide variability in duration of response, with some patients relapsing quickly and others with highly durable responses. Although several factors including measurable residual disease negativity and the presence of an NPM1 and/or IDH2 mutation have been associated with durable responses, it is currently difficult to predict which patients may achieve very prolonged remissions with Aza/Ven. This uncertainty may be stressful for patients and can make decisions regarding other available therapies such as allogeneic stem cell transplant challenging. We hypothesized that specifically studying the very long-term responders to Aza/Ven (an outlier group we have termed "Super Responders") may identify predictors of durable responses. Methods: To investigate predictors of very long-term response to Aza/Ven, charts of patients with newly diagnosed AML treated with Aza/Ven between January 2015 and December 2021 at a single institution were reviewed. Baseline patient demographic and clinical data was recorded, and responses to Aza/Ven were assessed according to ELN criteria. Patients who proceeded to transplant after responding to Aza/Ven were excluded from this analysis. To identify a group of Super Responders, event-free survival (EFS) was calculated and outliers were identified by Interquartile Range (IQR) box plot analysis. Clinical and disease characteristics of the Super Responders were then compared to the Non-Super Responders using chi-square or Fisher's exact tests for categorical variables and t-tests or Wilcoxon tests for continuous variables. Approval for this retrospective study was obtained from the Institutional Review Board. Results: Charts from 184 patients treated with frontline Aza/Ven for newly diagnosed AML were reviewed. After excluding 40 patients who proceeded to allogeneic transplant after response to Aza/Ven, 144 patients were analyzed. Fifteen outliers (termed Super Responders) with the longest EFS were identified by box plot analysis (Figure 1). These 15 patients also represented the top 10% of EFS (represented by green dots in Figure 1). The n=15 Super Responders had a median EFS of 31.8 months (range 23.7 to 84.6 months) compared to a median EFS of 3.4 months (range 0 to 20.8 months) among the n=129 Non-Super Responders (p<0.001). There was no significant difference in the frequency of secondary or treatment-related AML, SWOG cytogenetic classification, or ELN risk group when comparing the Super Responders to the Non-Super Responders (Table 1). Regarding molecular profile, mutations identified in Super Responders included: TET2 (n=7), SRSF2 (n=5), NPM1 (n=5), IDH2 (n=4), RUNX1 (n=2), IDH1 (n=2), DNMT3A (n=2), PHF6 (n=2), ASXL1 (n=2), TP53 (n=1), SF3B1 (n=1), and FLT3-TKD (n=1). The Super Responders had a higher incidence of IDH mutations, 40% vs 14% (p = .02). The rate of NPM1 mutations was not significantly different between groups, although 0% of subjects with NPM1 mutations in the Super Responder group had concomitant FLT3-ITD mutations compared to 40% in the Non-Super Responder group. No Ras pathway mutations were identified in Super Responders. Conclusions: Traditional prognostic factors including ELN risk group, cytogenetic classification, and having secondary or treatment-related AML do not predict whether a patient will have a highly durable response to Aza/Ven. Consistent with prior reports, IDH mutations (especially IDH2 mutations) are more common in Super Responders. NPM1 mutations did not appear to be more common in Super Responders in our analysis but this may be related to not controlling for the presence of a co-occurring FLT3-ITD mutation. Notably, no Super Responders had FLT3-ITD or Ras pathway mutations, consistent with prior data suggesting that Ras mutations may contribute to resistance to Aza/Ven. Multivariate analyses and analyses looking at the role of co-occurring mutations and measurable residual disease in predicting the likelihood of highly durable response to Aza/Ven are ongoing. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Effect of Intratrigonal Botulinum Toxin in Patients with Bladder Pain Syndrome/Interstitial Cystitis: A Long-Term, Single-Center Study in Real-Life Conditions.

The high percentage of treatment failures seen in patients with bladder pain syndrome/interstitial cystitis (BPS/IC) managed conservatively frequently demands invasive treatment options. We aimed to evaluate the long-term efficacy and adverse events of intratrigonal botulinum toxin injection in such circumstances, as well as to determine possible predictors of response to toxin treatment. A retrospective cohort study included 47 female BPS/IC patients treated with onabotulinum toxin A (OnabotA) in a tertiary hospital between the years 2009 and 2022. All patients received 100 U of OnabotA in ten injections limited to the trigonal area. Patients were divided into three groups based on their treatment response as responders, non-responders and lost to follow-up due to non-medical reasons. The clinical and surgical records of the individuals were retrieved, including the 10-point visual analogue scale (VAS), the number of treatments, the time between injections, and the age at the first injection. A total of 25 patients (>50% of the cohort) were long-term responders, but none of the evaluated parameters was a predictor for this circumstance: age, pain intensity, or duration of improvement following the injection. The time between injections was stable (around 1 year). No severe adverse events were registered. The intratrigonal injection of botulinum toxin in patients with BPS/IC was an effective and safe long-term treatment for patients' refractory to conservative forms of treatment. Age, basal pain intensity, and time to injection request did not predict long-term response to OnaBotA.

142P The predictive biomarker for immune-related adverse events (irAEs) in patients with metastatic renal cell carcinoma treated with the combination therapy of nivolumab plus ipilimumab: Musashino study-irAE

Combination immunotherapy with an anti-PD-1 inhibitor and an anti-CTLA-4 inhibitor is used as first-line therapy in metastatic renal cell carcinoma (mRCC). While providing the benefit of a certain population of long-term responders, the frequency of immune-related adverse events (irAEs) is known to be high with the combination therapy. Thus, predictive biomarkers of irAEs could help guide treatment strategies.

Serum cytokines predict efficacy and toxicity, but are not useful for disease monitoring in lung cancer treated with PD-(L)1 inhibitors.

PD-(L)1 inhibitors (IO) have improved the prognosis of non-small-cell lung cancer (NSCLC), but more reliable predictors of efficacy and immune-related adverse events (irAE) are urgently needed. Cytokines are important effector molecules of the immune system, whose potential clinical utility as biomarkers remains unclear. Serum samples from patients with advanced NSCLC receiving IO either alone in the first (1L, n=46) and subsequent lines (n=50), or combined with chemotherapy (ICT, n=108) were analyzed along with age-matched healthy controls (n=15) at baseline, after 1 and 4 therapy cycles, and at disease progression (PD). Patients were stratified in rapid progressors (RP, progression-free survival [PFS] <120 days), and long-term responders (LR, PFS >200 days). Cytometric bead arrays were used for high-throughput quantification of 20 cytokines and other promising serum markers based on extensive search of the current literature. Untreated NSCLC patients had increased levels of various cytokines and chemokines, like IL-6, IL-8, IL-10, CCL5, G-CSF, ICAM-1, TNF-RI and VEGF (fold change [FC]=1.4-261, p=0.026-9x10-7) compared to age-matched controls, many of which fell under ICT (FC=0.2-0.6, p=0.014-0.002), but not under IO monotherapy. Lower baseline levels of TNF-RI were associated with longer PFS (hazard ratio [HR]= 0.42-0.54; p=0.014-0.009) and overall survival (HR=0.28-0.34, p=0.004-0.001) after both ICT and IO monotherapy. Development of irAE was associated with higher baseline levels of several cytokines, in particular of IL-1β and angiogenin (FC=7-9, p=0.009-0.0002). In contrast, changes under treatment were very subtle, there were no serum correlates of radiologic PD, and no association between dynamic changes in cytokine concentrations and clinical outcome. No relationship was noted between the patients' serologic CMV status and serum cytokine levels. Untreated NSCLC is characterized by increased blood levels of several pro-inflammatory and angiogenic effectors, which decrease under ICT. Baseline serum cytokine levels could be exploited for improved prediction of subsequent IO benefit (in particular TNF-RI) and development of irAE (e.g. IL-1β or angiogenin), but they are not suitable for longitudinal disease monitoring. The potential utility of IL-1/IL-1β inhibitors in the management and/or prevention of irAE in NSCLC warrants investigation.

Phase II trial of daratumumab with DCEP in relapsed/refractory multiple myeloma patients with extramedullary disease

Extramedullary multiple myeloma (EMD) is an aggressive subentity of multiple myeloma (MM) with poor prognosis. As more innovative therapeutic approaches are needed for the treatment of MM with EMD, we conducted this multicenter, non-randomized phase II trial of daratumumab in combination with dexamethasone, cyclophosphamide, etoposide and cisplatin (DARA-DCEP). A total of 32 patients (median age 59, range 35–73) were treated with DARA-DCEP. Based on the best response during the study, the complete remission (CR) rate was 35.5% and overall response rate (ORR) 67.7%. During the median follow-up of 11 months, the median progression-free survival (PFS) was 5 months and median overall survival (OS) 10 months. There were 7 long-term responders whose median PFS was not reached. The most common grade ≥ 3 hematologic AE was thrombocytopenia. The most common non-hematologic AE was nausea (22.6%), followed by dyspepsia, diarrhea and stomatitis (all 12.9%). Grade ≥ 3 daratumumab infusion-related reaction was noted in 9.7% of the patients. Except for the planned 30% dose adjustment in cycle 1, only 2 patients required DCEP dose reduction. This is one of the very few prospective trials focusing on EMD and we successfully laid grounds for implementing immunochemotherapy in MM treatment.

Deep Brain Stimulation of the Central Lateral and Ventral Posterior Thalamus for Central Poststroke Pain Syndrome: Preliminary Experience

ObjectiveThe beneficial effects of thalamic deep brain stimulation (DBS) at various target sites in treating chronic central neuropathic pain (CPSP) remain unclear. This study aimed to evaluate the effectiveness of DBS at a previously untested target site in the central lateral (CL) thalamus, together with classical sensory thalamic stimulation (ventral posterior [VP] complex). Materials and MethodsWe performed a monocentric retrospective study of a consecutive series of six patients with CPSP who underwent combined DBS lead implantation of the CL and VP. Patient-reported outcome measures were recorded before and after surgery using the numeric rating scale (NRS), short-form McGill pain questionnaire (sf-MPQ), EuroQol 5-D quality-of-life questionnaire, and Beck Depression Inventory. DBS leads were reconstructed and projected onto a three-dimensional stereotactic atlas. ResultsNRS—but not sf-MPQ–rated pain intensity—was significantly reduced throughout the follow-up period of 12 months compared with baseline (p = 0.005, and p = 0.06 respectively, Friedman test). At the last available follow-up (12 to 30 months), three patients described a more than 50% reduction. Two of the three long-term responders were stimulated in the CL (1000 Hz, 90 μs, 3.5–5.0 mA), whereas the third preferred VP complex stimulation (50 Hz, 200 μs, 0.7–1.2 mA). No persistent procedure- or stimulation-associated side effects were noted. ConclusionsThese preliminary findings suggest that DBS of the CL might constitute a promising alternative target in cases in which classical VP complex stimulation does not yield satisfactory postoperative pain reduction. The results need to be confirmed in larger, prospective series of patients.

Long-Term Response to Tyrosine Kinase Inhibitors for Metastatic Renal Cell Carcinoma.

Background: Tyrosine kinase inhibitors (TKIs) prolong progression-free survival (PFS) in patients with metastatic renal cell carcinoma (mRCC), some of which may achieve long-term responses. Herein, we report clinical and pathological characteristics of patients who achieved long-term responses during first-line TKI treatment. Methods: Patients receiving TKI as first-line therapy from January 2010 to December 2017 in seven Italian Oncology Centers were reviewed. Sixty-six patients were considered as long-term responders, as they remained progression-free for 36 months or more during TKI treatment. A logistic regression model was performed to evaluate the effect of each clinical-pathological variable on the probability of responding long-term. Results: A total of 335 patients with a median age of 66 years were included in the analysis. The median PFS and overall survival among the long-term responders was 70 and 106 months, respectively. At a landmark PFS analysis performed 36 months after the start of treatment, the median PFS was 34 months. Multivariate analysis from all patients identified previous nephrectomy, Eastern Cooperative Oncology Group Performance Status (ECOG PS) < 1, and lack of liver metastasis as favorable prognostic factors for long-term response. Female gender and lack of liver metastasis positively correlated with long-term responses in favorable-risk-score population, as well as ECOG PS < 1 in intermediate-poor risk score population. Patients Summary: Previous surgery, clinical condition, and lack of liver metastasis may predict long-term responses to tyrosine kinase inhibitors. Conclusions: TKIs can lead to a long-term response in a subset of patients with metastatic RCC. Previous nephrectomy, optimal performance status (ECOG PS = 0), and lack of liver metastasis may predict long-term responses.

Targeting Homologous Recombination Deficiency in Ovarian Cancer with PARP Inhibitors: Synthetic Lethal Strategies That Impact Overall Survival.

Simple SummarySynthetic lethality approaches to cancer therapy involves combining events to cause cancer cell death. Using this strategy, major advances have occurred in the treatment of women with ovarian cancer who have defects in the Homologous Recombination Repair (HRR) pathway. When the HRR pathway is defective, due to mutations or epigenetic changes in genes such as BRCA1 or BRCA2, cells can no longer accurately repair double strand breaks (DSBs). Capitalising on this weakness, pharmacological inhibition of poly (ADP-ribose) polymerase (PARP) that function to repair single strand breaks (SSBs) leads to synthetic lethality in cells with defective HRR. PARP inhibitors (PARPis) including olaparib, niraparib and rucaparib are approved for the clinical management of women with ovarian cancer. Understanding and overcoming issues of acquired resistance to PARPis, extending these strategies to benefit more patients and combining PARPis with other drugs, including immunotherapies, are of high priority in the field today.The advent of molecular targeted therapies has made a significant impact on survival of women with ovarian cancer who have defects in homologous recombination repair (HRR). High-grade serous ovarian cancer (HGSOC) is the most common histological subtype of ovarian cancer, with over 50% displaying defective HRR. Poly ADP ribose polymerases (PARPs) are a family of enzymes that catalyse the transfer of ADP-ribose to target proteins, functioning in fundamental cellular processes including transcription, chromatin remodelling and DNA repair. In cells with deficient HRR, PARP inhibitors (PARPis) cause synthetic lethality leading to cell death. Despite the major advances that PARPis have heralded for women with ovarian cancer, questions and challenges remain, including: can the benefits of PARPis be brought to a wider range of women with ovarian cancer; can other drugs in clinical use function in a similar way or with greater efficacy than currently clinically approved PARPis; what can we learn from long-term responders to PARPis; can PARPis sensitise ovarian cancer cells to immunotherapy; and can synthetic lethal strategies be employed more broadly to develop new therapies for women with ovarian cancer. We examine these, and other, questions with focus on improving outcomes for women with ovarian cancer.

424P Avelumab added to FOLFIRI plus cetuximab followed by avelumab maintenance in patients with previously untreated RAS wild-type colorectal cancer: The phase-II FIRE-6 (AIO KRK-0118)

The FIRE-6 avelumab study (AIO KRK-0118) was performed in RAS-wild-type mCRC patients. This multi-center single-arm study tested the efficacy of avelumab maintenance during 1st-line therapy after 4 cycles of induction treatment with FOLFIRI plus cetuximab (FOLFIRI/Cet) followed by 4 cycles of combination treatment using FOLFIRI/Cet plus avelumab. Subsequently, treatment was continued with avelumab until progression or intolerable toxicity. Patients received FOLFIRI (irinotecan plus 5-FU/FA) every two weeks plus cetuximab weekly at the standard dosing schedule. After 4 cycles of therapy, avelumab (10mg/kg q2w) was added to FOLFIRI/Cet and continued for another 4 cycles before maintenance with avelumab monotherapy was started. Median progression-free survival (PFS) according to RECIST v1.1 was evaluated as primary endpoint. With a target PFS ≥ 12.88 months, the study was designed to reject the null hypothesis of PFS ≤8.0 months with a power of 80% at a one-tailed significance level of 0.025. Secondary endpoints included ORR, OS, safety, and tolerability. From November 2019 to June 2021, 57 patients were treated within the study protocol. Treatment with FOLFIRI/Cet plus avelumab was well tolerated and no new or unexpected toxicities were observed. Median PFS was 7.0 months in 47 evaluable patients. Overall response rate was 73.2% with a disease control rate of 87.5%. Median time on avelumab maintenance was 1.9 months with a range up to 15.6 months. Median OS was not reached at the time of the latest data cut-off with only 21.4% of OS events had occurred. With a median PFS of 7.0 months, FIRE-6 avelumab did not reach its pre-specified endpoint. Avelumab maintenance after FOLFIRI/Cet therefore is not effective to postpone disease progression after FOLFIRI/Cet induction therapy in first-line RASwt mCRC patients. Some long-term responders are present and will be further analyzed. FOLFIRI/Cet plus avelumab is safe and feasible as no unexpected toxicities occurred. FIRE-6 avelumab confirms the efficacy with respect to tumor response and disease control of FOLFIRI plus cetuximab as first-line treatment of patients with RAS wild-type mCRC.