The effect of neutralizing antibodies on the sustainable efficacy of biologic therapies: what’s in it for African and Middle Eastern rheumatologists

Characteristic analysis of adverse reactions of five anti-TNFɑ agents: a descriptive analysis from WHO-VigiAccess

Introduction: Tumor necrosis factor (TNF) inhibitors (adalimumab, infliximab, etanercept, golimumab, and certolizumab pegol) have revolutionized the treatment of severe immune-mediated inflammatory diseases, including rheumatoid arthritis, Crohn's disease, psoriatic arthritis, ankylosing spondylitis, and ulcerative colitis. This study assessed adverse drug reactions (ADRs) after the use of TNFα inhibitors in VigiAccess of the World Health Organization (WHO) and compared the adverse reaction characteristics of five inhibitors to select the drug with the least risk for individualized patient use. Methods: The study was a retrospective descriptive analysis method in design. We sorted out five marketed anti-TNFα drugs, and their ADR reports were obtained from WHO-VigiAccess. Data collection included data on the age groups, sex, and regions of patients worldwide covered by ADR reports, as well as data on disease systems and symptoms caused by ADRs recorded in annual ADR reports and reports received by the WHO. By calculating the proportion of adverse reactions reported for each drug, we compared the similarities and differences in adverse reactions for the five drugs. Results: Overall, 1,403,273 adverse events (AEs) related to the five anti-TNFα agents had been reported in VigiAccess at the time of the search. The results show that the 10 most commonly reported AE manifestations were rash, arthralgia, rheumatoid arthritis, headache, pneumonia, psoriasis, nausea, diarrhea, pruritus, and dyspnea. The top five commonly reported AE types of anti-TNFα drugs were as follows: infections and infestations (184,909, 23.0%), musculoskeletal and connective tissue disorders (704,657, 28.6%), gastrointestinal disorders (122,373, 15.3%), skin and subcutaneous tissue disorders (108,259, 13.5%), and nervous system disorders (88,498, 11.0%). The preferred terms of myelosuppression and acromegaly were obvious in golimumab. Infliximab showed a significantly higher ADR report ratio in the infusion-related reaction compared to the other four inhibitors. The rate of ADR reports for lower respiratory tract infection and other infections was the highest for golimumab. Conclusion: No causal associations could be established between the TNFα inhibitors and the ADRs. Current comparative observational studies of these inhibitors revealed common and specific adverse reactions in the ADR reports of the WHO received for these drugs. Clinicians should improve the rational use of these high-priced drugs according to the characteristics of ADRs.

Anti-adalimumab Antibodies in Patients with Non-infectious Ocular Inflammatory Disease: A Case Series

PURPOSE

To report the clinical course of patients with ocular inflammatory disease treated with adalimumab in whom anti-adalimumab antibodies (AAA) were detected.

METHODS

Single center case series.

RESULTS

Eight patients with initial response to adalimumab developed a disease flare associated with positive AAA testing after 5 to 76 months of therapy. Six patients were receiving no concurrent antimetabolite therapy at the time of AAA diagnosis and four had a temporary lapse in adalimumab therapy prior to AAA discovery. AAA resulted in undetectable drug levels in five of the seven patients for whom data were available, and adalimumab was discontinued in six of the eight patients. Of two patients continued on adalimumab, one maintained detectable serum adalimumab despite AAA and one had a low AAA titer.

CONCLUSIONS

For patients receiving adalimumab for ocular inflammatory disease, a disease flare in the setting of previously well-controlled disease should prompt consideration of AAA testing.

A novel anti-TNF scFv constructed with human antibody frameworks and antagonistic peptides

The introduction of TNF inhibitors has revolutionized the treatment of some chronic inflammatory diseases, e.g., rheumatoid arthritis and Crohn's disease. However, immunogenicity is one of the important mechanisms behind treatment failure, and generally, switching to another TNF inhibitor will be the first choice for patients and doctors, which results in unmet need for novel anti-TNF agents. Small antibody molecules with less number of epitope may be valuable in less immunogenicity. In this study, with the help of computer-guided molecular design, single-chain variable fragment (scFv) TSA2 was designed using consensus frameworks of human antibody variable region as scaffold to display anti-TNF antagonistic peptides. TSA2 showed evidently improved bioactivity over TSA1 (anti-TNF scFv explored before) and almost similar activity as S-Remicade (the scFv form of Remicade, anti-TNF antibody approved by FDA), especially in inhibiting TNF-induced cytotoxicity and NF-κB activation. Human antibody consensus frameworks with less immunogenicity have been used in the designing of VH domain antibody, scFv TSA1 and TSA2. A serial of TNF-related works convinced us that the novel design strategy was feasible and could be used to design inhibitors targeting more other molecules than TNF-α. More importantly, these designed inhibitors derived from computer modeling may form a virtual antibody library whose size depends on the number of candidate antagonistic peptides. It will be molecular-targeted virtual antibody library because of the specific antagonistic peptides and the potential antibodies could be determined by virtual screening and then confirmed by biologic experiments.