Impact of immunogenicity on response to anti-TNF therapy in moderate-to-severe plaque psoriasis: results of the PREDIR study

Formation and clinical effects of anti-drug antibodies against biologics in psoriasis treatment: An analysis of current evidence

BACKGROUND

Formation of anti-drug antibodies (ADAs) against biologics is an important cause of psoriasis treatment failure.

OBJECTIVE

This study aimed to summarize the characteristics of ADAs formation under different biological therapies and the influence of ADAs on the clinical effects and safety of biologics in patients with psoriasis.

METHODS

PubMed, Embase, and Web of Science databases were searched from their inception to August 2022. Studies on biologics that assessed ADA levels in patients with psoriasis were included. The Cochrane risk-of-bias tool was used to assess the quality of randomized controlled trials (RCTs), the Newcastle-Ottawa Quality Assessment Scale (NOS) for case-control and cohort studies, and the Joanna Briggs Institute (JBI) critical appraisal checklist for single-arm studies. We calculated the pooled incidence with a random-effects model using R software. Subgroup analyses revealed that differences in patient characteristics, disease conditions, study design, and immunoassays may influence ADA generation and detection.

RESULTS

The analysis included 86 studies, with a total population of 42,280 individuals. The pooled ADA rates were 0.49%, 2.20%, 2.38%, 4.08%, 7.38%, 7.94%, 14.29%, 21.93%, 29.70%, 31.76%, and 39.58% for secukinumab, etanercept, brodalumab, ustekinumab, tildrakizumab, guselkumab, ixekizumab, risankizumab, infliximab, adalimumab, and bimekizumab, respectively. >70% (95% CI, 0.71-0.81) of ADAs against adalimumab were neutralizing antibodies, and over 70% of ADAs against secukinumab and brodalumab were transient. Concomitant methotrexate therapy with tumor necrosis factor-α (TNF-α) inhibitors decreased ADA levels. Lower infliximab doses and intermittent therapy with interleukin (IL)-23 p19 inhibitors increased ADA formation. Additionally, ADA formation under treatment using TNF-α inhibitors and IL-12/23 p40 inhibitors was associated with lower response rates or serum drug levels, but only high ADA titers reduced the clinical effects of IL-17 inhibitors. The occurrence of IL-23 p19 and TNF-α inhibitors has been linked to injection-site reactions.

CONCLUSIONS

Among the 11 biologics, secukinumab, etanercept, and brodalumab resulted in the lowest ADA formation rates. Immunogenicity contributes to lower biological efficacy and a higher likelihood of injection-site reactions. Low doses, intermittent treatment may increase ADA formation. An appropriate biologic should be selected based on the ADA formation rate and course of treatment.

Population PK/PD modeling of low-density lipoprotein cholesterol response in hypercholesterolemic participants following administration of bococizumab, a potent anti-PCSK9 monoclonal antibody

We sought to characterize the population pharmacokinetic/pharmacodynamic (PK/PD) relationship of bococizumab (RN316/PF-04950615), a humanized IgG2Δa monoclonal antibody that binds to secreted human proprotein convertase subtilisin kexin type 9 (PCSK9), using data derived from 16 phase I, II, and III clinical studies (36,066 bococizumab observations, 46,790 low-density lipoprotein cholesterol [LDL-C] measurements, 3499 participants). A two-compartment disposition model with parallel linear and Michaelis-Menten elimination and an indirect response model was used to characterize the population PK and LDL-C response of bococizumab. Potential model parameters and covariate relationships were explored, and visual predictive checks were used for model assessment and validation. Key covariates included the effect of anti-drug antibodies (ADAs) on exposure through impact on clearance and bioavailability; impact of statins on bococizumab elimination (maximal rate of metabolism); and impact of statins, Asian race, and male sex on LDL-C efficacy (maximum effect). ADAs and neutralizing ADAs did not have additional effects on LDL-C beyond the influence on bococizumab exposure. In conclusion, the population PK/PD model adequately describes bococizumab concentration and LDL-C efficacy. The covariate effects are consistent with the presumed mechanism of action of PCSK9 inhibitors. With increasing availability of antibody-based therapeutics, improved understanding of the effect of ADAs and statins on bococizumab PK/PD adds to the literature and enhances our pharmacological understanding of how immunogenicity and concomitant medications may impact the PK/PD of biotherapeutics.

TWEAK functions with TNF and IL-17 on keratinocytes and is a potential target for psoriasis therapy

[Figure: see text].

Immunogenicity to biological drugs in psoriasis and psoriatic arthritis

Monoclonal antibodies or fusion proteins, defined as biological drugs, have modified the natural history of numerous immune-mediated disorders, allowing the development of therapies aimed at blocking the pathophysiological pathways of the disease, providing greater efficacy and safety than conventional treatment strategies. Virtually all therapeutic proteins elicit an immune response, producing anti-drug antibodies (ADAs) against hypervariable regions of immunoglobulins. Immunogenicity against biological drugs can alter their pharmacokinetic and pharmacodynamic properties, thereby reducing the efficacy of these drugs. In more severe cases, ADAs can neutralize the therapeutic effects of the drug or cause serious adverse effects, mainly hypersensitivity reactions. The prevalence of ADAs varies widely depending on the type of test used, occurrence of false-negative results, and non-specific binding to the drug, making it difficult to accurately assess their clinical impact. Concomitant use of immunosuppressors efficiently reduces the immunogenicity in a dose-dependent manner, either by decreasing the frequency of detectable ADAs or by delaying their appearance, thereby enhancing the effectiveness of biological therapies. Among the new therapeutic strategies for the management of psoriasis, biological agents have gained increasing importance in recent years as they interrupt key inflammation pathways involved in the physiopathology of the disease. Reports regarding ADA in new biologics are still scarce, but the most recent evidence tends to show little impact on the clinical response to the drug, even with prolonged treatment. It is therefore essential to standardize laboratory tests to determine the presence and titles of ADAs to establish their administration and management guidelines that allow the determination of the real clinical impact of these drugs.

Immunogenicity of biologic therapies in psoriasis: Myths, facts and a suggested approach

With biologic drugs dominating the therapeutic space for severe immune-mediated inflammatory disease, it is critical for clinicians to be familiar with the concept of drug immunogenicity, with the potential for our patients to develop antidrug antibodies (ADA) of clinical relevance. Whilst there are clear differences between different therapeutic biologics in terms of reported ADA rates, there is no accepted dermatology guideline or grouping of drugs by risk of clinically relevant ADA, nor a consensus on approach to ADA management. This is partly because making valid comparisons of immunogenicity across drugs is fundamentally flawed: the differing types of ADA assay, trial design and included patient population - as well as the molecular structure of the biologic molecules themselves - are all highly influential on reported ADA prevalence and impact on clinical response. Therefore, the first part of this article aims to give an overview of ADA that also clarifies common misconceptions on the subject, whilst the second part of this article outlines Phase III immunogenicity data on commonly used biologics for psoriasis, the most common dermatological indication. Based on this, and acknowledging current limitations in available evidence, we propose a working categorization of biologics together with a broad approach to management: Group 1 - biologics with higher risk of clinically relevant ADA; Group 2 - biologics with lower risk of clinically relevant ADA; and Group 3 - biologics with no established risk of clinically relevant ADA. However, these groupings represent a working concept only; more research is required, using comparable ADA assays and consistent reporting of related outcomes. Finally, there is an urgent need for better characterization of individuals at particular risk of developing ADA to inform future clinical decision-making.

TCPro: an In Silico Risk Assessment Tool for Biotherapeutic Protein Immunogenicity

Most immune responses to biotherapeutic proteins involve the development of anti-drug antibodies (ADAs). New drugs must undergo immunogenicity assessments to identify potential risks at early stages in the drug development process. This immune response is T cell-dependent. Ex vivo assays that monitor T cell proliferation often are used to assess immunogenicity risk. Such assays can be expensive and time-consuming to carry out. Furthermore, T cell proliferation requires presentation of the immunogenic epitope by major histocompatibility complex class II (MHCII) proteins on antigen-presenting cells. The MHC proteins are the most diverse in the human genome. Thus, obtaining cells from subjects that reflect the distribution of the different MHCII proteins in the human population can be challenging. The allelic frequencies of MHCII proteins differ among subpopulations, and understanding the potential immunogenicity risks would thus require generation of datasets for specific subpopulations involving complex subject recruitment. We developed TCPro, a computational tool that predicts the temporal dynamics of T cell counts in common ex vivo assays for drug immunogenicity. Using TCPro, we can test virtual pools of subjects based on MHCII frequencies and estimate immunogenicity risks for different populations. It also provides rapid and inexpensive initial screens for new biotherapeutics and can be used to determine the potential immunogenicity risk of new sequences introduced while bioengineering proteins. We validated TCPro using an experimental immunogenicity dataset, making predictions on the population-based immunogenicity risk of 15 protein-based biotherapeutics. Immunogenicity rankings generated using TCPro are consistent with the reported clinical experience with these therapeutics.

Secondary failure of TNF-α inhibitors in clinical practice

Tumor necrosis factor alpha (TNF-α) is a leading inflammatory cytokine that plays a pivotal role in the pathogenesis of psoriasis. In case of a severe course of psoriasis and moderate-to-severe disease in which traditional systemic treatments are ineffective or contraindicated, TNF-α inhibitors (iTNF-α) are used. This class of drugs includes monoclonal antibodies and a fusion protein (etanercept) and can induce a humoral or cell-mediated immune response, leading to formation of anti-drug antibodies (ADAs). The immunogenicity may affect iTNF-α drug pharmacokinetics, which would lead to hampering the clinical response (secondary drug failure), so a need to increase the drug dose arises. Antibodies against monoclonal antibodies (adalimumab, infliximab) have been associated with diminished clinical response, while against etanercept are non-neutralizing and appear to have no significant effect on clinical response and treatment safety. Switching of biologic agents may be one strategy in ADA-associated secondary failure of iTNF-α. However researches are needed to identify risk factors for ADA development and investigate management strategies for optimized treatment response. The authors reviewed the literature on the effectiveness of iTNF-α and pointed out the prevention of secondary failure in clinical practice.