10th European immunogenicity platform open symposium on immunogenicity of biopharmaceuticals.

Therapeutic proteins and emerging gene and cell-based therapies are attractive therapeutic tools for addressing unmet medical needs or when earlier conventional treatment approaches failed. However, the development of an immune response directed against therapeutic agents is a significant concern as it occurs in a substantial number of cases across products and indications. The specific anti-drug antibodies that develop can lead to safety adverse events as well as inhibition of drug activity or accelerated clearance, both phenomena resulting in loss of treatment efficacy. The European Immunogenicity Platform (EIP) is a meeting place for experts and newcomers to the immunogenicity field, designed to stimulate discussion amongst scientists across industry and academia, encourage interactions with regulatory agencies and share knowledge and the state-of-the-art of immunogenicity sciences with the broader scientific community. Here we report on the main topics covered during the EIP 10th Open Symposium on Immunogenicity of Biopharmaceuticals held in Lisbon, 26-27 February 2019, and the 1-d training course on practical and regulatory aspects of immunogenicity held ahead of the conference. These main topics included immunogenicity testing, clinical relevance of immunogenicity, immunogenicity prediction, regulatory aspects, tolerance induction as a mean to mitigate immunogenicity and immunogenicity in the context of gene therapy.

Secukinumab, a fully human anti-interleukin-17A monoclonal antibody, exhibits low immunogenicity in psoriasis patients treated up to 5 years.

BACKGROUND: Secukinumab is a fully human monoclonal antibody that selectively neutralizes IL-17A, a key cytokine involved in psoriasis and psoriatic arthritis development, and has shown rapid and long-lasting efficacy and safety in the complete spectrum of psoriasis manifestations. Monoclonal antibody therapies may be associated with the production of treatment-emergent antidrug antibodies (TE-ADAs) that can affect drug pharmacokinetics, diminish clinical responses via inhibition of target binding or cause hypersensitivity reactions. Secukinumab exhibited minimal immunogenicity up to 52 weeks in patients with moderate-to-severe plaque psoriasis, as evidenced by TE-ADA in <1% patients. OBJECTIVE: To investigate the immunogenicity of secukinumab treatment up to 5 years in two phase 3 extension studies (NCT01640951 and NCT01365455) in patients with moderate-to-severe plaque psoriasis. METHODS: Immunogenicity was evaluated up to Week 268 (5 years). TE-ADAs were defined as positive antidrug antibody (ADA) signals detected in post-treatment samples from patients with negative baseline signals. Confirmed positive samples were further analysed for their neutralizing potential. RESULTS: In total, 1821 patients entered the extension studies. Among patients receiving secukinumab and evaluated for ADAs (n = 1636), 32 developed TE-ADA, which resulted in an incidence of new TE-ADA cases below 1% per year. Neutralizing antibodies were detected in 9/32 (28%) patients with TE-ADA. Half of ADA-positive cases were transient. Among pharmacokinetic samples measured at the times of immunogenicity determination (n = 9992), 544 (5.4%) had secukinumab concentrations higher than the drug tolerance level of 53.8 µg/mL. There was no effect of TE-ADA, including neutralizing antibodies, on efficacy, safety or pharmacokinetics of secukinumab. CONCLUSION: The yearly secukinumab immunogenicity incidence over 5 years of treatment was consistently below 1% in patients with moderate-to-severe plaque psoriasis. Any TE-ADAs, including neutralizing antibodies, were not associated with loss of secukinumab efficacy or with clinical concerns.

Standardizing terms, definitions and concepts for describing and interpreting unwanted immunogenicity of biopharmaceuticals: recommendations of the Innovative Medicines Initiative ABIRISK consortium.

Biopharmaceuticals (BPs) represent a rapidly growing class of approved and investigational drug therapies that is contributing significantly to advancing treatment in multiple disease areas, including inflammatory and autoimmune diseases, genetic deficiencies and cancer. Unfortunately, unwanted immunogenic responses to BPs, in particular those affecting clinical safety or efficacy, remain among the most common negative effects associated with this important class of drugs. To manage and reduce risk of unwanted immunogenicity, diverse communities of clinicians, pharmaceutical industry and academic scientists are involved in: interpretation and management of clinical and biological outcomes of BP immunogenicity, improvement of methods for describing, predicting and mitigating immunogenicity risk and elucidation of underlying causes. Collaboration and alignment of efforts across these communities is made difficult due to lack of agreement on concepts, practices and standardized terms and definitions related to immunogenicity. The Innovative Medicines Initiative (IMI; www.imi-europe.org), ABIRISK consortium [Anti-Biopharmaceutical (BP) Immunization Prediction and Clinical Relevance to Reduce the Risk; www.abirisk.eu] was formed by leading clinicians, academic scientists and EFPIA (European Federation of Pharmaceutical Industries and Associations) members to elucidate underlying causes, improve methods for immunogenicity prediction and mitigation and establish common definitions around terms and concepts related to immunogenicity. These efforts are expected to facilitate broader collaborations and lead to new guidelines for managing immunogenicity. To support alignment, an overview of concepts behind the set of key terms and definitions adopted to date by ABIRISK is provided herein along with a link to access and download the ABIRISK terms and definitions and provide comments (http://www.abirisk.eu/index_t_and_d.asp).

Tetraspan microdomains distinct from lipid rafts enrich select peptide-MHC class II complexes.

Complexes of peptide and major histocompatibility complex (MHC) class II are expressed on the surface of antigen-presenting cells but their molecular organization is unknown. Here we show that subsets of MHC class II molecules localize to membrane microdomains together with tetraspan proteins, the peptide editor HLA-DM and the costimulator CD86. Tetraspan microdomains differ from other membrane areas such as lipid rafts, as they enrich MHC class II molecules carrying a selected set of peptide antigens. Antigen-presenting cells deficient in tetraspan microdomains have a reduced capacity to activate CD4+ T cells. Thus, the organization of uniformly loaded peptide-MHC class II complexes in tetraspan domains may be a very early event that determines both the composition of the immunological synapse and the quality of the subsequent T helper cell response.