The conservative, resource-intensive 3-tiered ADA testing strategy is under scrutiny for immunogenicity monitoring after two decades of use. A retrospective analysis of clinical ADA data from a mAb therapeutic using 1-tiered ADA testing strategy with a 1% false-positive cut point showed very similar results to the 3-tiered approach. This simplified strategy for ADA assessment could speed up data delivery and reduce resources for clinical program development without compromising patient safety.

Assessment of anti-drug antibody (ADA) and neutralizing antibody (NAb) is an important factor in contextualizing clinical study data. Recent guidance in incorporating immunogenicity information into drug product labeling underscores the need for consistency and scientific rigor to facilitate proper communication and understanding immunogenicity impact. To support this effort, a cross-industry group established harmonized recommendations and a report template for clearly summarizing the essential aspects of NAb clinical study testing and reporting. This talk will present the recommendations for NAb bioanalytical report elements such as the method, critical reagents, equipment, data analysis, and study results.

The presence of pre-existing antibodies to AAV presents a challenge in the development of systemically-delivered gene therapies. These antibodies can have a potential impact on transduction of target cells leading to reduced efficacy.  Therefore, pre-screening for anti-AAV antibodies in patients is a critical step in clinical development of AAV-based gene therapy. This presentation will discuss the technical and regulatory considerations in the development of phase-appropriate assays that can identify the right patients for the therapy. Critical activities towards co-development of a companion diagnostic that must parallel path drug development will be discussed.

Chemically modified Oligonucleotide therapeutics (ONT) have made tremendous progress in last two decades to address diseases that have been challenging to treat with small molecules or biologics. This talk will focus on factors to be considered for successful anti-drug antibody (ADA) assay development for supporting ONT based programs. A case study for development and validation of ELISA assays in monkey and human serum that meet the current regulatory guidelines for detection of ADA for STK-001, an antisense oligonucleotide in clinical development for treatment of Dravet Syndrome, will be described. Differences in the immunogenicity assays for supporting GLP toxicity studies and clinical studies, will be highlighted. Recommendations will be made for developing strategies for immunogenicity assessment for ONTs based on the available immunogenicity data for approved ONTs and regulatory expectations.

This study contains a case of immunogenicity risk assessment for FLT3L-Fc variants. We utilized various risk assessment methods that include in-silico prediction, dendritic cell loading, MHC-associated peptide proteomics, in-vitro HLA peptide binding, and in-vitro T cell proliferation and ELISpot assays. The results indicated that a single point mutation found on the FLT3L-Fc has the potential to introduce immunogenic T cell epitopes carrying a high immunogenic risk. Furthermore, our analysis of HLA genotyping suggests that certain HLA-DR alleles are highly associated with immunogenic response.

Subcutaneous delivery of therapeutic proteins can increase patient compliance and reduce burden on healthcare systems compared to intravenous infusion. However, subcutaneous administration has been proposed to increase immunogenicity. We reviewed anti-drug antibody (ADA) data for numerous biotherapeutics that were administered both intravenously and subcutaneously, and overall, no difference in immunogenicity incidence was observed. Although route of administration may in some instances influence ADA, other risk factors are likely more impactful.

Through development of an immune-specific consultation group, we present a model of risk assessment and focused clinical feedback to guide product teams through all phases of development and post-marketing. This model presents a novel and streamlined approach to addressing common concerns and unique issues throughout a global organization.

The original recognition of ADA and immune complex disease, the evolution of ADA responses, their continued impact on both clinical and preclinical studies, as well as novel ways to mitigate their formation will be examined.

Immunogenicity of biotherapeutics has the potential to negatively affect efficacy and patient safety. Identifying immunogenicity liabilities early in the discovery process of new therapeutic leads allows for the selection of alternative leads or protein engineering to mitigate these liabilities. Increased complexity of biotherapeutics (TCEs, ADCs, bispecific mAbs, engineered cytokines) can pose some unique challenges and can require modifications of the immunogenicity liabilities assessment strategy. Here we will discuss our discovery strategy to select and develop new biotherapeutics with minimized immunogenicity liabilities.

The development of anti-drug antibodies (ADAs) is a common cause for treatment failure and adverse events associated with biologic therapies. Here I will describe the development of ImmTOR tolerogenic nanoparticles to induce antigen-specific regulatory T cells. ImmTOR has been applied preclinically to mitigate ADAs against a wide range of immunogenic biologics, including adalimumab, coagulation factor VIII, enzyme replacement therapy, bacterial immunotoxin, and viral gene therapy vectors—and clinically to a fungal-derived uricase enzyme therapy for refractory gout, culminating in successful completion of Phase 3 clinical trials. I will further discuss some of the challenges and lessons learned from this experience.

Molecular therapeutic testing for eye disease is a major biomedical and pharmaceutical focus, but immune mechanisms that limit outcomes remains a challenge. Liquid biopsy proteomics can be used in living humans to identify specific immune pathways active in individuals to optimize human clinical trials in gene and molecular therapies.

Patient-centric sampling aims to improve the patient experience in clinical trials while maintaining quality assessments. In this case study, the application of capillary blood microsampling for immunogenicity aims to reduce the sampling burden for infants by decreasing volume and using a less invasive sampling technique. Assay development and validation will be presented alongside practical tips and clinical concordance.

We developed a new in silico immunogenicity profiling method with which we could show that biotherapeutic sequences can bear analogues to pathogen sequences. This may result in a high number of memory T cells that are cross-specific to the biotherapeutic and may result in unwanted immunogenicity in a large proportion of the patient population. This new method can be utilized in de-immunization approaches in early biotherapeutic development.