FDA-approved Therapy Research Articles

A phase 2 study of Bruton's tyrosine kinase inhibition for the prevention of anaphylaxis.

IgE-mediated anaphylaxis is a potentially fatal systemic allergic reaction for which there are no currently FDA-approved preventative therapies. Bruton's tyrosine kinase (BTK) is an essential enzyme for IgE-mediated signaling pathways, and is an ideal pharmacologic target to prevent allergic reactions. In this open-label trial, we evaluated the safety and efficacy of acalabrutinib, a BTK inhibitor that is FDA-approved to treat some B cell malignancies, in preventing clinical reactivity to peanut in adults with peanut allergy. After undergoing graded oral peanut challenge to establish their baseline level of clinical reactivity, 10 patients had a 6-week rest period, then received four standard doses of 100 mg acalabrutinib twice daily and underwent repeat food challenge. The primary endpoint was the change in patients' threshold dose of peanut protein to elicit an objective clinical reaction. At baseline, patients tolerated a median of 29 mg of peanut protein before objective clinical reaction. During subsequent food challenge on acalabrutinib, patients' median tolerated dose significantly increased to 4,044 mg (range, 444 - 4,044 mg). Seven patients tolerated the maximum protocol amount (4,044 mg) of peanut protein with no clinical reaction, and the other 3 patients' peanut tolerance increased between 32- and 217-fold. Three patients experienced a total of 4 adverse events that were considered to be possibly related to acalabrutinib; all events were transient and nonserious. Acalabrutinib pretreatment achieved clinically-relevant increases in patients' tolerance to their food allergen, thereby supporting the need for larger, placebo-controlled trials. gov NCT05038904FUNDING. AstraZeneca Pharmaceuticals, the Johns Hopkins Institute for Clinical and Translational Research, the Ludwig Family Foundation, and NIH grants AI143965 and AI106043.

EBV Reactivation and Lymphomagenesis: More Questions than Answers.

Epstein-Barr Virus (EBV) is a ubiquitous herpesvirus that affects almost all humans and establishes lifelong infections by infecting B-lymphocytes leading to their immortalization. EBV has a discrete life cycle with latency and lytic reactivation phases. EBV can reactivate and cause lymphoproliferation in both immunocompetent and immunocompromised individuals. There is sparse literature on monitoring protocols for EBV reactivation and no standardized treatment protocols to treat EBV-driven lymphoproliferation. While there are no FDA-approved therapies to treat EBV, there are several strategies to inhibit EBV replication. These include immunosuppression reduction, nucleoside analogs, HDAC inhibitors, EBV-specific cytotoxic T-lymphocytes (CTLs), and monoclonal antibodies, such as rituximab. There is currently an open clinic trial combining the use of a HDAC inhibitor, nanatinostat, and ganciclovir to treat refractory/relapsed EBV lymphomas. Another novel therapy includes tabelecleucel, which is an allogenic EBV-directed T-cell immunotherapy that was approved by the European Medicines Agency, but is currently only available in the US for limited use in relapsed or refractory EBV-positive PTLD. Further research is needed to establish EBV monitoring protocols in high-risk populations, such as those with autoimmune disease, cancer, HIV, or receiving immunosuppressive therapy. Additionally, standardized treatments for both the prevention of EBV reactivation in high-risk populations and treatment of EBV reactivation and lymphoproliferation need to be established.

AARDVARK: an automated reversion detector for variants affecting resistance kinetics.

Resistance to two classes of FDA-approved therapies that target DNA repair-deficient tumors is caused by mutations that restore the tumor cell's DNA repair function. Identifying these "reversion" mutations currently requires manual annotation of patient tumor sequence data. Here we present AARDVARK, an R package that automatically identifies reversion mutations from DNA sequence data. AARDVARK is implemented in R (≥3.5). It is available on GitHub at https://github.com/davidquigley/aardvark. It is licensed under the MIT license.

Intranasally Administered MSC-Derived Extracellular Vesicles Reverse Cisplatin-Induced Cognitive Impairment.

Neurotoxic side effects of chemotherapy include deficits in attention, memory, and executive functioning. Currently, there are no FDA-approved therapies. In mice, cisplatin causes long-term cognitive deficits, white matter damage, mitochondrial dysfunction, and loss of synaptic integrity. We hypothesized that MSC-derived small extracellular vesicles (sEVs) could restore cisplatin-induced cognitive impairments and brain damage. Animals were injected with cisplatin intraperitoneally and treated with MSC-derived sEVs intranasally 48 and 96 h after the last cisplatin injection. The puzzle box test (PBT) and the novel object place recognition test (NOPRT) were used to determine cognitive deficits. Synaptosomal mitochondrial morphology was analyzed by transmission electron microscopy. Immunohistochemistry using antibodies against synaptophysin and PSD95 was applied to assess synaptic loss. Black-Gold II staining was used to quantify white matter integrity. Our data show that sEVs enter the brain in 30 min and reverse the cisplatin-induced deficits in executive functioning and working and spatial memory. Abnormalities in mitochondrial morphology, loss of white matter, and synaptic integrity in the hippocampus were restored as well. Transcriptomic analysis revealed upregulation of regenerative functions after treatment with sEVs, pointing to a possible role of axonal guidance signaling, netrin signaling, and Wnt/Ca2+ signaling in recovery. Our data suggest that intranasal sEV treatment could become a novel therapeutic approach for the treatment of chemobrain.

Aberrant Glycosylation as Immune Therapeutic Targets for Solid Tumors.

Glycosylation occurs at all major types of biomolecules, including proteins, lipids, and RNAs to form glycoproteins, glycolipids, and glycoRNAs in mammalian cells, respectively. The carbohydrate moiety, known as glycans on glycoproteins and glycolipids, is diverse in their compositions and structures. Normal cells have their unique array of glycans or glycome which play pivotal roles in many biological processes. The glycan structures in cancer cells, however, are often altered, some having unique structures which are termed as tumor-associated carbohydrate antigens (TACAs). TACAs as tumor biomarkers are glycan epitopes themselves, or glycoconjugates. Some of those TACAs serve as tumor glyco-biomarkers in clinical practice, while others are the immune therapeutic targets for treatment of cancers. A monoclonal antibody (mAb) to GD2, an intermediate of sialic-acid containing glycosphingolipids, is an example of FDA-approved immune therapy for neuroblastoma indication in young adults and many others. Strategies for targeting the aberrant glycans are currently under development, and some have proceeded to clinical trials. In this review, we summarize the currently established and most promising aberrant glycosylation as therapeutic targets for solid tumors.

PET imaging of TREM1 identifies CNS-infiltrating myeloid cells in a mouse model of multiple sclerosis.

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system (CNS) that causes substantial morbidity and diminished quality of life. Evidence highlights the central role of myeloid lineage cells in the initiation and progression of MS. However, existing imaging strategies for detecting myeloid cells in the CNS cannot distinguish between beneficial and harmful immune responses. Thus, imaging strategies that specifically identify myeloid cells and their activation states are critical for MS disease staging and monitoring of therapeutic responses. We hypothesized that positron emission tomography (PET) imaging of triggering receptor expressed on myeloid cells 1 (TREM1) could be used to monitor deleterious innate immune responses and disease progression in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS. We first validated TREM1 as a specific marker of proinflammatory, CNS-infiltrating, peripheral myeloid cells in mice with EAE. We show that the 64Cu-radiolabeled TREM1 antibody-based PET tracer monitored active disease with 14- to 17-fold higher sensitivity than translocator protein 18 kDa (TSPO)-PET imaging, the established approach for detecting neuroinflammation in vivo. We illustrate the therapeutic potential of attenuating TREM1 signaling both genetically and pharmacologically in the EAE mice and show that TREM1-PET imaging detected responses to an FDA-approved MS therapy with siponimod (BAF312) in these animals. Last, we observed TREM1+ cells in clinical brain biopsy samples from two treatment-naïve patients with MS but not in healthy control brain tissue. Thus, TREM1-PET imaging has potential for aiding in the diagnosis of MS and monitoring of therapeutic responses to drug treatment.

Animal Models of Osteoarthritis: Updated Models and Outcome Measures 2016-2023.

Osteoarthritis (OA) is a global musculoskeletal disorder that affects primarily the knee and hip joints without any FDA-approved disease-modifying therapies. Animal models are essential research tools in developing therapies for OA; many animal studies have provided data for the initiation of human clinical trials. Despite this, there is still a need for strategies to recapitulate the human experience using animal models to better develop treatments and understand pathogenesis. Since our last review on animal models of osteoarthritis in 2016, there have been exciting updates in OA research and models. The main purpose of this review is to update the latest animal models and key features of studies in OA research. We used our existing classification method and screened articles in PubMed and bibliographic search for animal OA models between 2016 and 2023. Relevant and high-cited articles were chosen for inclusion in this narrative review. Recent studies were analyzed and classified. We also identified ex vivo models as an area of ongoing research. Each animal model offers its own benefit in the study of OA and there are a full range of outcome measures that can be assessed. Despite the vast number of models, each has its drawbacks that have limited translating approved therapies for human use. Depending on the outcome measures and objective of the study, researchers should pick the best model for their work. There have been several exciting studies since 2016 that have taken advantage of regenerative engineering techniques to develop therapies and better understand OA. Osteoarthritis (OA) is a chronic debilitating disease without any cure that affects mostly the knee and hip joints and often results in surgical joint replacement. Cartilage protects the joint from mechanical forces and degrades with age or in response to injury. The many contributing causes of OA are still being investigated, and animals are used for preclinical research and to test potential new treatments. A single consensus OA animal model for preclinical studies is non-existent. In this article, we review the many animal models for OA and provide a much-needed update on studies and model development since 2016.

Curriculum Innovations: Inspiring Neurology Residents to Pursue Fellowship Training in Movement Disorders.

The aging US population has led to the increased prevalence of neurodegenerative diseases and the critical need for specialists with advanced training in the management of these conditions. Focus on Common Movement Disorders (FOCMD), a 2-day educational course hosted by Vanderbilt University, was started 16 years ago to provide neurology residents with exposure to the diagnosis and treatment of movement disorders. The aim of the course was to provide early-career neurology residents with relevant exposure to the field of movement disorders, through which we hope to increase medical knowledge of movement disorders and common Food and Drug Administration (FDA)-approved therapies and inspire residents to pursue fellowship training in the field. FOCMD consists of lectures and small-group workshops that provide an overview of common movement disorders and approved therapies. All North American neurology residency program directors are invited to nominate a first-year or second-year resident. Attendees are administered standardized multiple-choice precourse and postcourse examinations to assess foundational knowledge of common movement disorders and FDA-approved therapies and to measure acquisition of the course material. Past participants are regularly surveyed to gauge their impression of the course's effect on fellowship selection and their utilization of therapies common in the treatment of movement disorders. Since 2008, FOCMD has trained 854 neurology residents from 113 programs. Between 2010 and 2020, 507 residents completed the precourse and postcourse examinations. There was an increase of 22.4 (95% CI 20.67-24.49; p < 0.001) percentage points between the precourse and postcourse examinations or an additional 3.8 questions were answered correctly. Follow-up surveys were sent to 414 past participants, and 116 were completed. Survey responses revealed that 84% of past attendees completed a fellowship, 44% of which were in the field of movement disorders. In addition, 82% of past participants reported that the course affected subspecialty selection and 63% reported treating patients with movement disorders in their current practice. Experience with FOCMD has shown it to be successful in introducing neurology residents to the subspecialty early in their career and increasing medical knowledge on movement disorders. An educational program of this format may also positively influence fellowship selection.

Probenecid ameliorates testosterone-induced benign prostatic hyperplasia: Implications of PGE-2 on ADAM-17/EGFR/ERK1/2 signaling cascade.

Benign prostatic hyperplasia (BPH) is one of the most prevalent clinical disorders in the elderly. Probenecid (Prob) is a well-known FDA-approved therapy for gout owing to its uricosuric effect. The present study evaluated the use of Prob for BPH as a COX-2 inhibitor. Prob (100 and 200 mg/kg) was intraperitoneally injected into male Wistar rats daily for 3 weeks. In the second week, testosterone (3 mg/kg) was subcutaneously injected to induce BPH. Compared with BPH-induced rats, Prob treatment reduced prostate weight and index and improved histopathological architecture. The protease activity of ADAM-17/TACE and its ligands (TGF-α and TNF-α) were regulated by prob, which in turn abolished EGFR phosphorylation, and several inflammatory mediators (COX-2, PGE2, NF-κB (p65), and IL-6) were suppressed. By reducing the nuclear import of extracellular regulated kinase protein 1/2 (ERK1/2), Prob helped re-establish the usual equilibrium between antiapoptotic proteins like Bcl-2 and cyclin D1 and proapoptotic proteins like Bax. All of these data point to Prob as a promising treatment for BPH because of its ability to inhibit COX-2-syntheiszed PGE2 and control the ADAM-17/TGF-α-induced EGFR/ERK1/2 signaling cascade. These findings might help to repurpose Prob for the treatment of BPH.

1273-P: Guidance to Persons Who Screen Positive for Islet Autoantibodies and Their Health Care Providers—Ask the Experts

Objective: Detecting early-stage type 1 diabetes (T1D) by screening for islet autoantibodies (IA) can prevent serious morbidity at clinical onset and allow for a trial prevention, e.g., FDA-approved teplizumab therapy. The Ask the Experts program provides confirmation of positive screening results, monitoring, and education for individuals who screen positive for IA as well as their families and health care providers (HCPs). Methods: Individuals and HCPs concerned for T1D (e.g., screen positive for IA) can enroll in Ask the Experts via phone, e-mail or website. We recommend and facilitate screening or confirmation of IA status and collect demographic and clinical data. When IA positivity is confirmed, we partner with HCPs to provide early T1D training and collaborative follow-up, customized to HCP interest and clinical capacity. Results: We have enrolled 71 participants to date, mostly youth (83%), aged 1 to 62 years (61% female; 79% non-Hispanic white). Most referrals were for confirmation of IA results (52%) or HCP concern for early T1D based on dysglycemic HbA1c or glucose (30%). IA were measured at 6 commercial laboratories, including the Barbara Davis Center Autoantibody Laboratory with 53% screening positive for a single IA and 47% for multiple IA. The most common IA detected was insulinoma antigen-2 IA (48%) with glutamic decarboxylase 65 and insulin IAs both present in 41% of those who screened positive. Of those who presented with one or more IA on screening, 66% were negative for all four major IA on confirmation testing completed at the Barbara Davis Center Autoantibody Laboratory. 80% of individuals confirmed IA positive have engaged in remote monitoring while 20% have been followed by their local HCP with our training and support. Conclusion: Persons who screen positive for IA should have confirmation testing completed given the discordance between screening and confirmation results. HCPs require support for following screening detected individuals. Disclosure K.M.Simmons: Advisory Panel; Provention Bio, Inc., Consultant; Dexcom, Inc., Provention Bio, Inc., Research Support; Novartis. K.A.Bautista: None. C.Geno rasmussen: None. R.Karban: None. H.K.O'donnell: None. B.I.Frohnert: Advisory Panel; Provention Bio, Inc. A.Steck: None. M.Rewers: Research Support; Provention Bio, Juvenile Diabetes Research Foundation (JDRF), Hemsley Charitable Trust, Dexcom, Inc., Janssen Research &amp; Development, LLC. Funding The Leona M. and Harry B. Helmsley Charitable Trust

582-P: Exercise Training Reverses NAFLD in Mice with Obesity Independent of Changes in Hepatic Mitochondrial Oxidative Capacity

Obesity is a primary cause of hepatic lipid accumulation, leading to nonalcoholic fatty liver disease (NAFLD). As there are no FDA-approved therapies for NAFLD treatment, weight loss through lifestyle intervention is the first-line therapy. Exercise improves hepatic function in patients with obesity related NAFLD. However, the mechanisms whereby exercise mediates the enhancement of liver function are largely unknown. This study evaluated the impact of exercise training on NAFLD in mice with obesity. At 8 weeks of age, mice were randomized to low-fat (LFD) or high-fat diet (HFD). After 4 weeks of dietary intervention, mice were randomized to either control (SED) or exercise training (ExT) with experimental diet for 10 weeks. ExT mice completed 45 minutes of moderate-intensity treadmill running 4 days/week. Body weight was measured weekly, and body composition and maximal treadmill running were evaluated at weeks 0, 4, and 14. Blood lactate accumulation was measured during the final treadmill test. Mice were euthanized 48 hours after the last exercise session for liver histopathology, blood chemistry, and ex vivo mitochondrial function analysis. Liver function was assessed via serum liver panel and quantification of hepatic lipids. High-resolution respirometry was used to determine maximal hepatic fatty acid oxidation, NADH- and succinate-linked oxidative phosphorylation (OXPHOS), and electron transfer capacity in tissue homogenates. HFD increased body mass, which was reduced with ExT. ExT increased maximal running time independent of diet. HFD worsened lactate metabolism, which was improved with ExT. HFD increased liver weight, which was decreased with ExT. HFD-induced increases in hepatic lipid and serum ALT and ALP were reversed with ExT. Hepatic mitochondrial OXPHOS and electron transfer were reduced with HFD relative to LFD. These data suggest that exercise-induced reversal of NAFLD is not mediated by hepatic mitochondrial oxidative capacity. Disclosure E.C. Heintz: None. W.S. Dantas: None. J.E. Stampley: None. G.M. Davis: None. B.A. Irving: None. C.L. Axelrod: None. J.P. Kirwan: None. Funding Nutrition Obesity Research Center (P30DK072476); Louisiana Clinical and Translational Science Center (U54GM104940); Centers of Biomedical Research Excellence (P20GM103528)

Engineered Extracellular Vesicles Derived from Dermal Fibroblasts Attenuate Inflammation in a Murine Model of Acute Lung Injury.

Acute respiratory distress syndrome (ARDS) represents a significant burden to the healthcare system, with ≈200000 cases diagnosed annually in the USA. ARDS patients suffer from severe refractory hypoxemia, alveolar-capillary barrier dysfunction, impaired surfactant function, and abnormal upregulation of inflammatory pathways that lead to intensive care unit admission, prolonged hospitalization, and increased disability-adjusted life years. Currently, there is no cure or FDA-approved therapy for ARDS. This work describes the implementation of engineered extracellular vesicle (eEV)-based nanocarriers for targeted nonviral delivery of anti-inflammatory payloads to the inflamed/injured lung. The results show the ability of surfactant protein A (SPA)-functionalized IL-4- and IL-10-loaded eEVs to promote intrapulmonary retention and reduce inflammation, both in vitro and in vivo. Significant attenuation is observed in tissue damage, proinflammatory cytokine secretion, macrophage activation, influx of protein-rich fluid, and neutrophil infiltration into the alveolar space as early as 6 h post-eEVs treatment. Additionally, metabolomics analyses show that eEV treatment causes significant changes in the metabolic profile of inflamed lungs, driving the secretion of key anti-inflammatory metabolites. Altogether, these results establish the potential of eEVs derived from dermal fibroblasts to reduce inflammation, tissue damage, and the prevalence/progression of injury during ARDS via nonviral delivery of anti-inflammatory genes/transcripts.

Abstract B031: Investigation of the ubiquitin ligase RNF31 as a mediator of immune evasion in advanced prostate cancer

Abstract Background: Metastatic Castration-Resistance Prostate cancer (mCRPC) is a disease state associated with poor survival. Current FDA-approved therapies are non-curative and can only extend mCRPC patient survival by a few months. Therefore, there is an unmet need to improve therapies for patients with advanced disease. Immunotherapy is an effective treatment strategy for a number of cancers but showed limited success in mCRPC patients. Prostate cancer cells exhibit reduced surface expression of major histocompatibility complex (MHC) molecules as an evasive mechanism from cytotoxic CD8+ T-cells. Natural killer (NK) cells are another class of immune cells with anti-tumor characteristics and can target cancer cells independently of MHC expression. Increased NK cell infiltration and activity in prostate cancer has been associated with favorable patient outcomes, but cancer cells have evolved resistance mechanisms against NK cell targeting. We hypothesize that there are druggable pathways that can be exploited to enhance anti-tumor activities of NK cells and improve efficacy of immunotherapies. Methods: To investigate these pathways, we established and characterized an in vitro co-culture system between prostate cancer and NK cells. We conducted the first targeted pool CRISPR screen identifying genes that, when knockout (KO) in prostate cancer cells, enhance killing by NK cells. We validated the screen by individually KO the gene hits. To explore the potential resistance mechanisms conferred by these hits, we performed RNA seq in control and KO cells. Results: Our screen nominated several known ligands of NK cells including CD58 and PVRL2, as well as RNF31 as the top novel target in promoting NK-mediated kill of cancer cells. RNF31 is upregulated in prostate cancer and is part of a druggable linear ubiquitin chain assembly complex (LUBAC). Single sgRNA validation experiments confirmed that RNF31 KO significantly sensitized LNCaP cells to NK92-mediated depletion. Importantly, RNF31 KO did not affect cancer cell proliferation, suggesting that the observed effects are due to the actions of NK cells. We observed that immune response related genes were upregulated in the RNF31 KO cells compare to the wildtype cells. Furthermore, pharmacologic inhibiting RNF31 via LUBAC inhibitor Hopin-8 sensitizes LNCaP cell to NK cell mediated kill. Conclusions: We anticipate that results from this study will yield insights into a novel tumor-intrinsic mechanism of immune evasion in prostate cancer and evaluate the therapeutic potential of targeting this pathway. We hope this work will help identify new therapeutic options or combination treatments that can improve the efficacy of immunotherapy in prostate cancer and significantly extend the lives of patients with advanced prostate cancer. Acknowledgements: This study was supported by the DOD Early Investigator Research Award to TL. Citation Format: Tianyi Liu, Haolong Li, Tony Junjie Hua, Hyunjin Shin, Tanushree Shenoy, Martin Sjoestroem, Arian Lundberg, Luke Gilbert, David Quigley, Alan Ashworth, Lewis Lanier, Felix Feng. Investigation of the ubiquitin ligase RNF31 as a mediator of immune evasion in advanced prostate cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Prostate Cancer Research; 2023 Mar 15-18; Denver, Colorado. Philadelphia (PA): AACR; Cancer Res 2023;83(11 Suppl):Abstract nr B031.

Real-world rates of FDA-approved targeted therapy and immunotherapy prescriptions for patients with metastatic colorectal cancer in the VA’s National Precision Oncology Program (NPOP).

3602 Background: Colorectal cancer is the fourth most common cancer among Veterans and the third leading cause of cancer-related death in the USA. Use of comprehensive genomic profiling (CGP) to guide administration of FDA-approved biomarker directed therapies can improve outcomes among metastatic CRC (mCRC) patients. We sought to compute the rates of actionable biomarkers and prescriptions of associated FDA-approved therapies among Veterans in NPOP. Methods: The NPOP database was queried to identify mCRC patients who had undergone CGP via tissue or liquid biopsy between February 2019 and July 2022 and had one of the following 5 actionable biomarker profiles: NRAS/ KRAS/ BRAF wildtype, BRAF V600E, MSI-H, TMB-H, or NTRK fusion or rearrangement. The VA’s Corporate Data Warehouse (CDW) was queried to extract prescription data for seven FDA-approved biomarker-directed therapies (targeted agents and immune checkpoint inhibitors (ICIs)). Rates of CGP-directed therapy prescriptions were assessed based upon biomarker and patient characteristics (sex, race, ethnicity, and rurality). Results: A total of 908 mCRC patients underwent CGP, with 81.4% bearing colon adenocarcinoma (COAD) and 18.6% rectal adenocarcinoma (READ). Rates of actionable biomarkers associated with FDA-approved therapies were as follows: NRAS/ KRAS/ BRAF wildtype (34.4%), TMB-H (9.6%), BRAF V600E (7.7%), MSI-H (5.6%), TMB-H and MSI-H (5.6%), and NTRK Fusion or rearrangement (0.3%). The combined rates of any actionable variant were 47.4% for COAD and 44.4% for READ patients. Relative to patients without actionable biomarkers, patients with BRAF V600E mutations were more likely to be older and white; patients with NRAS/ KRAS/ BRAF wildtype were more likely to be younger (all p &lt; 0.001). Among the 424 eligible patients, the frequencies of FDA-approved CGP-directed therapy prescriptions were as follows: MSI-H (70.7%), TMB-H (47.4%), NRAS/ KRAS/ BRAF wildtype (38.5%), and BRAF V600E (17.1%). Across all included biomarkers, African Americans (53.4%) were more likely to receive these therapies than whites (36.8%); and patients with prescriptions were more likely to be younger that those without (all p &lt; 0.01). Conclusions: Nearly 30% of patients with MSI-H mCRC did not receive efficacious ICIs, and though disease laterality data was not readily available, a substantial number of eligible patients also did not receive EGFR inhibitors. This underuse of EGFR inhibitors has been reported previously [1].There were racial and age differences in prescription rates. Further studies should evaluate the barriers to prescribing CGP-directed therapies in the care of mCRC patients. Keywords: molecular testing, metastatic colorectal cancer, comprehensive genomic profiling, actionable biomarkers, FDA approved therapies, veterans. [1] Becker et al. 2021 PMID 34250412.

Survival outcomes associated with liver-directed therapies in patients with metastatic uveal melanoma.

9590 Background: Metastatic uveal melanoma (mUM) is characterized by a hepatotropic pattern of spread and poor outcomes. Tebentafusp, the only FDA approved therapy, is restricted to patients (pts) with the HLA-A*02:01 genotype. As a result, a variety of liver-directed therapies (LDT) are commonly used for management of hepatic metastases. Methods: Pts with mUM with hepatic metastases who underwent LDT, including radiofrequency ablation, microwave ablation, hepatic metastatectomy, Yttrium-90 radioembolization (SIRT), transarterial chemoembolization (TACE), bland embolization, and immunoembolization (IE), were identified from an institutional database. Data collected included: age, gender, tumor location and size, baseline liver function tests (LFT) and lactate dehydrogenase (LDH), molecular tumor characteristics (where available), type(s) of LDT received, systemic therapies received, and vital status. Time from onset of hepatic metastasis until death (Liver-OS), as well as time from initial diagnosis of primary uveal melanoma until death (Ocular-OS) were calculated. Results: A total of 119 pts were identified. The median age at diagnosis was 53.8 years (range 26-83), 47% were female. At the time of LDT initiation, 33% had bilobar disease and 16% had extrahepatic metastasis. 18% pts had elevated LFTs and 55% had elevated LDH. 72% of pts had M1a disease, 24% had M1b and 4% had M1c disease. 45% of pts received more than one form of LDT. SIRT (31%) was the commonly administered initial LDT, followed closely by IE (26%) and TACE (9%). 86% of pts received systemic therapy including 42% who received immune checkpoint blockade overlapping with LDT. Molecular profiling in 26 pts revealed recurrent mutations in BAP1 (n = 18) and SF3B1 (n = 8). The median ocular-OS across all pts was 71.0 months (95% confidence intervals (CI), 62.8-99.4). The median liver-OS across all pts was 31.8 months (95% CI 25.2-35.3). In pts who received TACE, IE, or SIRT exclusively (n = 44), the median Liver-OS was 15.2 months (95% CI 12.8-NA) for TACE (n = 8), 23.3 months (95% CI 15.8-NA) for SIRT (n = 28), and 28.2 months (95% CI 22.6-NA) for IE (n = 8). Conclusions: Our results provide additional support for the utilization of LDT in pts with mUM, as demonstrated by improved OS compared to historical survival data.

CfDNA NGS detection of fusions acquired as mechanisms of resistance in the post-EGFR setting across multiple solid tumors.

3053 Background: Oncogenic fusions are rare but have targetable, FDA-approved therapies across all solid tumor types. These fusions have been associated with resistance to EGFR-TKI (EGFRi) in advanced non-small cell lung cancer (NSCLC) and anti-EGFR antibodies in colorectal cancer (CRC), but the prevalence of acquired fusions and their associated clinical outcomes have not been well-studied. We examined fusions in &gt;5,000 patients with advanced NSCLC or CRC who had a history of EGFR-directed therapy in the GuardantINFORM clinical-genomic database. Methods: Fusions in ALK, FGFR1-3, NTRK1-3, ROS1 and RET were examined in a cohort of 2,379 patients with NSCLC and 1,072 with CRC tested with Guardant360 or Guardant360 CDx (Guardant Health, Redwood City, CA) before approved EGFR-targeting therapies, and in 3,531 patients with NSCLC and 2,132 patients with CRC tested after EGFR therapy. Fusion clonality was calculated as the fusion variant allele fraction (VAF):max somatic VAF for each patient, with subclonal fusions defined as having clonality &lt; 0.5. Clinical outcomes were compared between patients with and without fusions in the post-EGFR population, adjusting for age, gender, regimen/line of therapy, and max VAF. Comparisons of fusion prevalence pre- and post-EGFR therapy were performed using Fisher’s exact test. Results: Fusions were detected more frequently in patients with NSCLC and CRC after EGFR therapy relative to pretreatment (NSCLC: 3.2% vs. pre-EGFR 0.5%, p&lt;0.05; CRC: 6.4% vs. pre-EGFR 1.1%, p&lt;0.05). Fusions in RET were most enriched in the post-EGFR NSCLC population (1.0% vs. pre-EGFR 0.1%, OR=11.6, p&lt;0.05), while fusions in the FGFR family were most enriched in the post-EGFR CRC population (3.0% vs. pre-EGFR 0.3%, OR=10.8, p&lt;0.05). The majority of fusions post-EGFR were subclonal in patients with NSCLC (86%) and CRC (96%), consistent with these fusions emerging as mechanisms of resistance. In patients with NSCLC, clinical outcomes (as measured by time-to-next-treatment (TTNT)) were significantly shorter in patients who acquired fusions compared to those without fusions (median 5.9 vs. 9.5 months, log-rank p=0.01, adjusted HR=1.7, adjusted p=0.02). Patients with CRC showed no significant difference in TTNT between those with and without acquired fusions. In patients with NSCLC who acquired fusions, 45% received an EGFRi in the next line and 23% received a TKI targeted to their fusion; TTNT on these therapies was not significantly different (median 5.3 months vs. 6.4 months, respectively). Conclusions: Fusions in patients with NSCLC and CRC were enriched post-EGFR therapy and were associated with inferior clinical outcomes in NSCLC. Recognition of the subclonal prevalence of acquired fusions provides important context as oncologists consider the next line of therapy. This work highlights the potential utility of genomic profiling in patients over the course of treatment.

HRD signature and HRD genomic landscape of tumors from 896 patients with early-stage breast cancer (BC).

539 Background: Pathologic mutations in BRCA1, BRCA2 and PALB2 lead to impaired homologous recombination repair (HRR). Cells with defects in HRR are dependent on non-homologous DNA end joining for DNA repair through the poly(ADP-ribose) polymerase (PARP) catalytic activity. PARP inhibitors (olaparib, talazoparib) are FDA-approved therapies that are toxic to tumors with HRR deficiency (HRD) and are recommended as adjuvant therapy in high-risk germline BRCA (g BRCA) positive BC. Despite the clinical implications of HRD, the prevalence of HRR alterations and HRD signature in early-stage primary BC and its association with hormone receptor (HR) status has not been well characterized. Methods: This study used the nationwide (US-based, ~280 US cancer clinics) de-identified Flatiron Health-Foundation Medicine BC clinico-genomic database and included patients (pts) who underwent tissue comprehensive genomic profiling (FoundationOne/FoundationOneCDx) between 2014 and 2022. The analysis included all pts with BC who presented with “early” stage I-III disease), had a primary tissue specimen collected within 3 months of diagnosis, and had a reportable novel scar-based HRD signature (HRDsig). Results: A total of 896 primary BC pts with stage I-III met our inclusion criteria. Of these early BC pts 21% (188/896) were HRDsig+ (stage I: 17% (32/188); stage II: 22% (84/376); and stage III: 22% (72/332)). For early BC pts, high rates of HRDsig+ were seen in g BRCA (87% [34/39]), somatic BRCA (s BRCA, 78% [14/18]), and g PALB2 (71% [5/7]) mutated tumors, with a lower rate seen with other HRR genes [16% (10/63); ATM, BARD1, BRIP1, CDK12, CHEK1, CHEK2, FANCL, sPALB2, RAD51B, RAD51C, RAD51D and RAD54L]. HRDsig+ was also detected in 16% (135/832) of BC without g/s BRCA or g PALB2 mutations. BC pts who presented with stage I-III disease has similar prevalence of HRDsig+ when compared to those with stage IV disease (21% [188/896] vs 23% [177/767], p = 0.31), with similar trends in HR+ disease (HR+/HER2+: 7% [4/57] vs 9% [4/45], p = 0.73; and HR+/HER2-: 17% [78/466] vs 18% [82/463], p = 0.73). Conversely, in HR- cohorts, decreased prevalence of HRDsig+ was observed in the stage I-III vs stage IV cohort (HR-/HER2+: 3% [1/38] vs 18% [6/33], p = 0.04; HR-/HER2-: 31% [99/321] vs 38% [83/216], p = 0.08). Conclusions: In this study, HR+/HER2- group was the most common early BC subtype, followed by HR-/HER2-, HR+/HER2+, and HR-/HER2+. This distribution is similar to the SEER study, and closely reflects that of the general population. We observed the expected high rates of HRDsig+ in early-stage BC pts with g/s BRCA or g PALB2 mutations where clinical trial data already support the use of PARP inhibitors for early and advanced disease. Importantly, HRDsig positivity was also seen in 16% of early BC without g/s BRCA or g PALB2, and clinical trials will be needed to determine if these pts could also benefit from HRD directed therapies.

Final overall survival analysis of JUPITER-02: A phase 3 study of toripalimab versus placebo in combination with gemcitabine and cisplatin as first-line treatment for recurrent or metastatic nasopharyngeal carcinoma (NPC).

6009 Background: There are currently no FDA-approved IO therapies for NPC. Toripalimab in combination with Gemcitabine-Cisplatin (GP) chemotherapy had shown significant improvement over chemotherapy alone in progression-free survival (PFS) as first-line treatment for recurrent or metastatic (r/m) NPC at the interim PFS analysis of JUPITER-02 (NCT03581786) study. The final overall survival (OS) analysis results are summarized here. Methods: Patients with r/m NPC (n = 289) were randomized (1:1) to receive toripalimab 240 mg (n = 146) or placebo (n = 143) in combination with GP once every 3 weeks (Q3W) for up to 6 cycles, followed by monotherapy with toripalimab or placebo Q3W until disease progression, intolerable toxicity, or completion of 2 years of treatment. Stratification factors were ECOG performance score (0 vs. 1) and extent of disease (recurrent vs. primary metastatic) at enrollment. The primary endpoint was PFS by an independent review committee. Secondary endpoints included OS and safety. Results: By the cutoff date of Nov 18, 2022, when 133 events were reached for the final OS analysis, the median survival follow up was 30.1 months. A significant improvement in OS was observed for the toripalimab arm over the placebo arm: HR = 0.63 (95% CI: 0.45-0.89), two-sided p = 0.0083. The median OS was not reached in the toripalimab arm and was 33.7 months in the placebo arm. The 2-year and 3-year OS rates were 78.0% vs. 65.1%, and 64.5% vs. 49.2% respectively. A consistent effect on OS, favoring the toripalimab arm, was observed in nearly all subgroups, including PD-L1 high and PD-L1 low expression subgroups. No new safety signals were identified in the toripalimab arm since the interim report. The incidence of Grade ≥3 adverse events (AEs) (89.7% vs 90.2%) and fatal AEs (3.4% vs 2.8%) were similar between two arms. However, AEs leading to discontinuation of toripalimab/placebo (11.6% vs 4.9%), immune-related (irAEs) (54.1% vs. 21.7%) and Grade ≥3 irAEs (9.6% vs. 1.4%) were more frequent in the toripalimab arm. Conclusions: The addition of toripalimab to GP chemotherapy as 1st-line treatment for r/m NPC provided clinically important and highly significant OS advantage over GP alone with a manageable safety profile. These results support the use of toripalimab with GP chemotherapy as the new standard care for this population. Clinical trial information: NCT03581786 .

Quantifying the growth of clinical actionability in precision oncology using OncoKB.

1577 Background: OncoKB ( www.oncokb.org ), Memorial Sloan Kettering's (MSK) precision oncology knowledge base, contains curated information about the oncogenic effect and therapeutic implications of somatic alterations in cancer and is the first cancer variant database to be partially recognized by the US-FDA. Individual mutations and structural alterations in OncoKB are assigned a level of evidence based on whether the alteration is a predictive biomarker of response or resistance to a genomically matched standard care or investigational drug in a specific cancer subtype. As of February 2023, OncoKB includes annotations for &gt;6200 alterations in &gt;700 cancer-associated genes, including 50 level 1 or 2 standard care genes (specified in the FDA drug label or professional guidelines) as well as 9 level 3A and 12 level 4 genes (predictive of drug response based on well-powered clinical studies or compelling biological evidence, respectively). OncoKB data is used internally to annotate &gt;15,000 MSK patient sequencing reports annually, and its content is integrated into the cBioPortal for Cancer Genomics. Methods: To quantitate the expansion of the clinical actionability landscape in precision oncology, we annotated the clinical sequencing results of 47,271 solid tumor samples from the AACR Project GENIE cohort (GENIE 11.0 - public) using two versions of OncoKB, the first from March 2017 and the second from November 2022. Results: From 2017 to 2022, we observed a 22.7% increase in the fraction of samples with a standard care biomarker (levels 1 and 2), and a 21.4% decrease in the fraction of samples with a driver alteration that was not clinically actionable. The tumor agnostic approvals of the anti-PD1 antibody pembrolizumab in microsatellite instability high (MSI-H) and tumor mutational burden high (TMB-H) solid tumors resulted in a 11.1%increase of samples with a level 1 biomarker. In sum, of the 38,722 samples across 66 cancer types with limited to no actionability in 2017 (levels 3B, 4 or no level), 21.7% became clinically actionable (levels 1, 2 or 3A) by November 2022. This is an upper bound estimate as it includes samples that may have been eligible for an FDA-approved precision oncology therapy based on cancer subtype alone. Conclusions: Our analysis highlights the significant expansion of precision oncology-based therapeutic options for patients with cancer over the past 5 years, as well as the ongoing unmet need for novel precision oncology approaches designed to address oncogenic but not currently actionable drug targets. [Table: see text]

Implementing liquid biopsy in rural cancer care when tissue is insufficient for molecular testing: Retrospective review.

e15039 Background: Liquid biopsy is a promising and minimally invasive genetic test examining plasma circulating tumor DNA. Coupled with the rapidly developing next-generation sequencing (NGS) technologies, it holds the potential for implementation in selecting signal-matched therapeutic options. Analysis of tumor cell free DNA, or liquid biopsy, is emerging as a useful adjunct to tissue biopsies in advanced solid tumors. These tests may reduce the need for repeating invasive biopsies, and may be performed serially with minimal risk to patients. Many a times solid tumor biopsies are not sufficient enough to run next generation sequencing and hence the need for repeat biopsies. The purpose of our study is to document how liquid biopsies are being used in a large, diverse community based practice in rural Missouri where travel to tertiary care center for repeat biopsies is not easy and how often the results were able to demonstrate yield of finding FDA approved therapeutic options or clinical trials for these patients. Methods: A retrospective chart review was conducted on adult patients with advanced solid tumors whose tumors were not sufficient enough to be tested for next generation sequencing and hence tested with Guardant360 assay, between December 2015 and December 2022. A total of 515 patients were referred for testing by 4 oncologists from within a five satellite rural community cancer centers. Results: The majority of patients were tested upfront for molecular marker evaluation, in either newly diagnosed advanced cancer patients, or in recurrent patients without enough tissue for testing. 66 out of 515 patients (12.8 %) were not found to have any tumor alterations on liquid biopsy. A total of 16 histological types were tested among 449 patients with lung ( n = 177; (39.42% ),breast cancer ( n = 58; 12.9 %) and colorectal ( n = 135; 30 % ); cancers being the most common types of the 16 histological subtypes. Of those with positive test results (n = 449 ), 56 (12.4%) patients had ≥ 1 FDA approved, target-matched therapeutic opportunity. Similarly, 329 patients (73%) had ≥ 1 target-matched therapeutic opportunity, outside current indications. Lastly, when no FDA-approved target-matched therapy was available results from liquid biopsy testing offered signal-based clinical trial opportunity in all 449 patients. Conclusions: Implementation of NGS-based liquid biopsy testing is feasible within a community rural oncology practice. In the era of precision oncology, such assays have the potential to expedite the efforts towards target-matched therapies and signal-based clinical trial opportunities especially when there is problem of lack of accessibility and affordability of repeat biopsies is a problem.