2023 White Paper on Recent Issues in Bioanalysis: ISR for ADA Assays, the Rise of dPCR vs qPCR, International Reference Standards for Vaccine Assays, Anti-AAV TAb Post-Dose Assessment, NanoString Validation, ELISpot as Gold Standard (Part 3 - Recommendations on Gene Therapy, Cell Therapy, Vaccines Immunogenicity & Technologies; Biotherapeutics Immunogenicity & Risk Assessment; ADA/NAb Assay/Reporting Harmonization).

The 17th Workshop on Recent Issues in Bioanalysis (17th WRIB) took place in Orlando, FL, USA on June 19-23, 2023. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 17th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week to allow an exhaustive and thorough coverage of all major issues in bioanalysis of biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on "EU IVDR 2017/746 Implementation and impact for the Global Biomarker Community: How to Comply with these NEW Regulations" and on "US FDA/OSIS Remote Regulatory Assessments (RRAs)" were the special features of the 17th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2023 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2023 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations on Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity. Part 1A (Mass Spectrometry Assays and Regulated Bioanalysis/BMV), P1B (Regulatory Inputs) and Part 2 (Biomarkers, IVD/CDx, LBA and Cell-Based Assays) are published in volume 16 of Bioanalysis, issues 8 and 9 (2024), respectively.

2022 White Paper on Recent Issues in Bioanalysis: FDA Draft Guidance on Immunogenicity Information in Prescription Drug Labeling, LNP & Viral Vectors Therapeutics/Vaccines Immunogenicity, Prolongation Effect, ADA Affinity, Risk-based Approaches, NGS, qPCR, ddPCR Assays (Part 3 - Recommendations on Gene Therapy, Cell Therapy, Vaccines Immunogenicity & Technologies; Immunogenicity & Risk Assessment of Biotherapeutics and Novel Modalities; NAb Assays Integrated Approach).

The 2022 16th Workshop on Recent Issues in Bioanalysis (WRIB) took place in Atlanta, GA, USA on September 26-30, 2022. Over 1000 professionals representing pharma/biotech companies, CROs, and multiple regulatory agencies convened to actively discuss the most current topics of interest in bioanalysis. The 16th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on ICH M10 BMV final guideline (focused on this guideline training, interpretation, adoption and transition); mass spectrometry innovation (focused on novel technologies, novel modalities, and novel challenges); and flow cytometry bioanalysis (rising of the 3rd most common/important technology in bioanalytical labs) were the special features of the 16th edition. As in previous years, WRIB continued to gather a wide diversity of international, industry opinion leaders and regulatory authority experts working on both small and large molecules as well as gene, cell therapies and vaccines to facilitate sharing and discussions focused on improving quality, increasing regulatory compliance, and achieving scientific excellence on bioanalytical issues. This 2022 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2022 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations on Gene Therapy, Cell therapy, Vaccines and Biotherapeutics Immunogenicity. Part 1 (Mass Spectrometry and ICH M10) and Part 2 (LBA, Biomarkers/CDx and Cytometry) are published in volume 15 of Bioanalysis, issues 16 and 15 (2023), respectively.

Impact of Organ Impairment on the Pharmacokinetics of Therapeutic Peptides and Proteins.

The kidneys and liver are major organs involved in eliminating small-molecule drugs from the body. Characterization of the effects of renal impairment (RI) and hepatic impairment (HI) on pharmacokinetics (PK) have informed dosing in patients with these organ impairments. However, the knowledge about the impact of organ impairment on therapeutic peptides and proteins is still evolving. In this study, we reviewed how often therapeutic peptides and proteins were assessed for the effect of RI and HI on PK, the findings, and the resulting labeling recommendations. RI effects were reported in labeling for 30 (57%) peptides and 98 (39%) proteins and HI effects for 20 (38%) peptides and 55 (22%) proteins. Dose adjustments were recommended for RI in 11 of the 30 (37%) peptides and 10 of the 98 (10%) proteins and for HI in 7 of the 20 (35%) peptides and 3 of the 55 (5%) proteins. Additional actionable labeling includes risk mitigation strategies; for example, some product labels have recommended avoid use or monitor toxicities in patients with HI. Over time, there is an increasing structural diversity of therapeutic peptides and proteins, including the use of non-natural amino acids and conjugation technologies, which suggests a potential need for reassessing the need to evaluate the effect of RI and HI. Herein, we discuss scientific considerations for weighing the risk of PK alteration due to RI or HI for peptide and protein products. We briefly discuss other organs that may affect the PK of peptides and proteins administered via other delivery routes.

FDA Approval Summary: Mobocertinib for Metastatic Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations.

On September 15, 2021, the FDA granted accelerated approval to mobocertinib (Exkivity, Takeda Pharmaceuticals USA, Inc.) for the treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion mutations, as detected by an FDA-approved test, whose disease has progressed on or after platinum-based chemotherapy. The approval was based on data from Study AP32788-15-101 (NCT02716116), an international, non-randomized, multi-cohort clinical trial that included patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations. The overall response rate in 114 patients whose disease had progressed on or after platinum-based chemotherapy was 28% [95% confidence interval (CI), 20%-37%] with a median duration of response of 17.5 months (95% CI, 7.4-20.3). The most common adverse reactions (>20%) were diarrhea, rash, nausea, stomatitis, vomiting, decreased appetite, paronychia, fatigue, dry skin, and musculoskeletal pain. Product labeling includes a Boxed Warning for QTc prolongation and torsades de pointes. This is the first approval of an oral targeted therapy for patients with advanced EGFR exon 20 insertion mutation-positive NSCLC.

2021 White Paper on Recent Issues in Bioanalysis: TAb/NAb, Viral Vector CDx, Shedding Assays; CRISPR/Cas9 & CAR-T Immunogenicity; PCR & Vaccine Assay Performance; ADA Assay Comparability & Cut Point Appropriateness (Part 3 - Recommendations on Gene Therapy, Cell Therapy, Vaccine Assays; Immunogenicity of Biotherapeutics and Novel Modalities; Integrated Summary of Immunogenicity Harmonization).

The 15th edition of the Workshop on Recent Issues in Bioanalysis (15th WRIB) was held on 27 September to 1 October 2021. Even with a last-minute move from in-person to virtual, an overwhelmingly high number of nearly 900 professionals representing pharma and biotech companies, contract research organizations (CROs), and multiple regulatory agencies still eagerly convened to actively discuss the most current topics of interest in bioanalysis. The 15th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on biomarker assay development and validation (BAV) (focused on clarifying the confusion created by the increased use of the term "Context of Use - COU"); mass spectrometry of proteins (therapeutic, biomarker and transgene); state-of-the-art cytometry innovation and validation; and, critical reagent and positive control generation were the special features of the 15th edition. This 2021 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2021 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations on TAb/NAb, Viral Vector CDx, Shedding Assays; CRISPR/Cas9 & CAR-T Immunogenicity; PCR & Vaccine Assay Performance; ADA Assay Comparability & Cut Point Appropriateness. Part 1A (Endogenous Compounds, Small Molecules, Complex Methods, Regulated Mass Spec of Large Molecules, Small Molecule, PoC), Part 1B (Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine) and Part 2 (ISR for Biomarkers, Liquid Biopsies, Spectral Cytometry, Inhalation/Oral & Multispecific Biotherapeutics, Accuracy/LLOQ for Flow Cytometry) are published in volume 14 of Bioanalysis, issues 9 and 10 (2022), respectively.

Elucidating the Impact of Immunogenicity Assessment Postapproval: A Targeted Analysis of Immunogenicity Postmarketing Requirements and Commitments.

Insufficient availability of data to evaluate immunogenicity incidence or clinical impact during regulatory review could require further evaluation postapproval. Through a keyword search of all postmarketing requirements and commitments (PMRs/PMCs) associated with products with their original US Food and Drug Administration (FDA) approvals between 2009 and 2018, we identified products that had PMRs/PMCs established to address concerns or uncertainty related to immunogenicity. Of the 113 relevant products, 50% had an immunogenicity-related PMR/PMC; of these, 68% were related to developing immunogenicity assays and 48% requested an assessment of clinical impact. Fifty-five percent of the products with a fulfilled PMR/PMC had a change in the immunogenicity information in their labeling immediately following fulfillment. This work highlights that there are often unknowns associated with immunogenicity incidence and/or impact at the time of approval. Earlier regulatory discussions on immunogenicity assessments in premarket development could improve the understanding and communication of the risk/benefit profile and reduce the need for some immunogenicity PMRs/PMCs.

A Systematic Assessment of US Food and Drug Administration Dosing Recommendations For Drug Development Programs Amenable to Response-Guided Titration.

A key goal in drug development is optimized dosing for patients. Interactions between drug developers and regulatory scientists throughout development are important for the optimization of dosing and serve as a forum to discuss approaches for optimal dosing, such as precision or individualized dosing. To date, there has not been a systematic assessment of the advice provided by the US Food and Drug Administration (FDA) to drug developers from an individualized dosing perspective. Here, we reviewed FDA recommendations on dose selection for efficacy trials at end-of-phase meetings between the FDA and drug developers for 76 new molecular entities approved between 2013 and 2017 that are considered amenable for an individualized dosing method, response-guided titration. Forty FDA dosing recommendations were identified as specific to dose selection and design of the respective efficacy trials and subsequently: (i) characterized based on if they were supportive of individualized dosing and (ii) compared with dosing regimens used in efficacy trials and labeling at approval to evaluate if FDA recommendations were implemented. Of these 40 recommendations for efficacy trials, 35 (88%) were considered supportive of individualized dosing. Eighteen of these 40 recommendations (45%) were incorporated into efficacy trials and 11 (28%) were incorporated into labeling. This research suggests that early FDA-sponsor interactions can support the study of doses in efficacy trials that may lead to individualized dosing strategies in labeling.

Communicating Immunogenicity-Associated Risk in Current U.S. FDA Prescription Drug Labeling: A Systematic Evaluation.

BACKGROUND: Communicating the clinical impact of immunogenicity in labeling is important for safe and effective use of certain prescription products. Current U.S. Food and Drug Administration (FDA) guidance does not provide comprehensive recommendations on the communication of clinical impact of immunogenicity in labeling. To understand current labeling practice, we evaluated the immunogenicity data and clinical impact information in labeling of selected prescription products. METHODS: We created a database of 71 therapeutic biologics and drug products that had an immunogenicity assessment initially approved by FDA's Center for Drug Evaluation and Research between 2014 and 2018. We analyzed the content and format of immunogenicity information (e.g., anti-drug antibody incidence and/or immunogenicity impact on pharmacokinetics (PK), safety, and/or effectiveness) in the most recent approved labeling. RESULTS: Immunogenicity information was in the ADVERSE REACTIONS section in 98% of the reviewed labeling. Immunogenicity impact on PK was reported in 52% of the labeling, typically within the ADVERSE REACTIONS section, but supportive PK data were often not included in the CLINICAL PHARMACOLOGY section. Additionally, the immunogenicity impact on safety and/or effectiveness was communicated in 70% of the labeling, with 23% clearly communicating the effect as clinically meaningful, and 10% providing actionable recommendations. CONCLUSIONS: Most of the reviewed labeling includes immunogenicity information within the ADVERSE REACTIONS section. However, there is inconsistency in providing supportive PK data and high variability in reporting immunogenicity impact on safety and effectiveness in labeling. Development of a communication framework that allows for consistent inclusion of immunogenicity impact statements in labeling could improve how immunogenicity risk is conveyed in prescription drug labeling.

2018 White Paper on Recent Issues in Bioanalysis: focus on flow cytometry, gene therapy, cut points and key clarifications on BAV (Part 3 - LBA/cell-based assays: immunogenicity, biomarkers and PK assays).

The 2018 12th Workshop on Recent Issues in Bioanalysis took place in Philadelphia, PA, USA on April 9-13, 2018 with an attendance of over 900 representatives from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day full immersion in bioanalysis, biomarkers and immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule bioanalysis involving LCMS, hybrid LBA/LCMS and LBA/cell-based assays approaches. This 2018 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2018 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations for large molecule bioanalysis, biomarkers and immunogenicity using LBA and cell-based assays. Part 1 (LCMS for small molecules, peptides, oligonucleotides and small molecule biomarkers) and Part 2 (hybrid LBA/LCMS for biotherapeutics and regulatory agencies' inputs) are published in volume 10 of Bioanalysis, issues 22 and 23 (2018), respectively.

SIK2 Restricts Autophagic Flux To Support Triple-Negative Breast Cancer Survival.

Triple-negative breast cancer (TNBC) is a highly heterogeneous disease with multiple, distinct molecular subtypes that exhibit unique transcriptional programs and clinical progression trajectories. Despite knowledge of the molecular heterogeneity of the disease, most patients are limited to generic, indiscriminate treatment options: cytotoxic chemotherapy, surgery, and radiation. To identify new intervention targets in TNBC, we used large-scale, loss-of-function screening to identify molecular vulnerabilities among different oncogenomic backgrounds. This strategy returned salt inducible kinase 2 (SIK2) as essential for TNBC survival. Genetic or pharmacological inhibition of SIK2 leads to increased autophagic flux in both normal-immortalized and tumor-derived cell lines. However, this activity causes cell death selectively in breast cancer cells and is biased toward the claudin-low subtype. Depletion of ATG5, which is essential for autophagic vesicle formation, rescued the loss of viability following SIK2 inhibition. Importantly, we find that SIK2 is essential for TNBC tumor growth in vivo Taken together, these findings indicate that claudin-low tumor cells rely on SIK2 to restrain maladaptive autophagic activation. Inhibition of SIK2 therefore presents itself as an intervention opportunity to reactivate this tumor suppressor mechanism.

Comprehensive functional characterization of cancer-testis antigens defines obligate participation in multiple hallmarks of cancer.

Tumours frequently activate genes whose expression is otherwise biased to the testis, collectively known as cancer-testis antigens (CTAs). The extent to which CTA expression represents epiphenomena or confers tumorigenic traits is unknown. In this study, to address this, we implemented a multidimensional functional genomics approach that incorporates 7 different phenotypic assays in 11 distinct disease settings. We identify 26 CTAs that are essential for tumor cell viability and/or are pathological drivers of HIF, WNT or TGFß signalling. In particular, we discover that Foetal and Adult Testis Expressed 1 (FATE1) is a key survival factor in multiple oncogenic backgrounds. FATE1 prevents the accumulation of the stress-sensing BH3-only protein, BCL-2-Interacting Killer (BIK), thereby permitting viability in the presence of toxic stimuli. Furthermore, ZNF165 promotes TGFß signalling by directly suppressing the expression of negative feedback regulatory pathways. This action is essential for the survival of triple negative breast cancer cells in vitro and in vivo. Thus, CTAs make significant direct contributions to tumour biology.

Multiple cancer testis antigens function to support tumor cell mitotic fidelity.

While the expression of genes that are normally involved in spermatogenesis is frequently detected in tumors, the extent to which these gene products are required for neoplastic behaviors is unclear. To begin to address their functional relevance to tumorigenesis, we identified a cohort of proteins which display synthetic lethality with paclitaxel in non-small-cell lung cancer and whose expression is biased toward testes and tumors. Remarkably, these testis proteins, FMR1NB, NXF2, MAGEA5, FSIP1, and STARD6, are required for accurate chromosome segregation in tumor cells. Their individual depletion enhances the generation of multipolar spindles, increases mitotic transit time, and induces micronucleation in response to an otherwise innocuous dose of paclitaxel. The underlying basis for abnormal mitosis is an alteration in microtubule function, as their depletion increases microtubule cytaster formation and disrupts microtubule stability. Given these observations, we hypothesize that reactivated testis proteins may represent unique tumor cell vulnerabilities which, if targeted, could enhance responsiveness to antimitotic therapy. Indeed, we demonstrate that combining paclitaxel with a small-molecule inhibitor of the gametogenic and tumor cell mitotic protein TACC3 leads to enhanced centrosomal abnormalities, activation of death programs, and loss of anchorage-independent growth.

Thin-walled microvessels in human coronary atherosclerotic plaques show incomplete endothelial junctions relevance of compromised structural integrity for intraplaque microvascular leakage.

OBJECTIVES: This study sought to examine the ultrastructure of microvessels in normal and atherosclerotic coronary arteries and its association with plaque phenotype. BACKGROUND: Microvessels in atherosclerotic plaques are an entry point for inflammatory and red blood cells; yet, there are limited data on the ultrastructural integrity of microvessels in human atherosclerosis. METHODS: Microvessel density (MVD) and ultrastructural morphology were determined in the adventitia, intima-media border, and atherosclerotic plaque of 28 coronary arteries using immunohistochemistry for endothelial cells (Ulex europeaus, CD31/CD34), basement membrane (laminin, collagen IV), and mural cells (desmin, alpha-smooth muscle [SM] actin, smoothelin, SM1, SM2, SMemb). Ultrastructural characterization of microvessel morphology was performed by electron microscopy. RESULTS: The MVD was increased in advanced plaques compared with early plaques, which correlated with lesion morphology. Adventitial MVD was higher than intraplaque MVD in normal arteries and early plaques, but adventitial and intraplaque MVD were similar in advanced plaques. Although microvessel basement membranes were intact, the percentage of thin-walled microvessels was similarly low in normal and atherosclerotic adventitia, in the adventitia and the plaque, and in all plaque types. Intraplaque microvascular endothelial cells (ECs) were abnormal, with membrane blebs, intracytoplasmic vacuoles, open EC-EC junctions, and basement membrane detachment. Leukocyte infiltration was frequently observed by electron microscopy, and confirmed by CD45RO and CD68 immunohistochemistry. CONCLUSIONS: The MVD was associated with coronary plaque progression and morphology. Microvessels were thin-walled in normal and atherosclerotic arteries, and the compromised structural integrity of microvascular endothelium may explain the microvascular leakage responsible for intraplaque hemorrhage in advanced human coronary atherosclerosis.