Missense variants in the TNFA epitopes and their effects on interaction with therapeutic antibodies—in silico analysis

Background Tumor necrosis factor alpha (TNFA) is an important cytokine that influences multiple biological processes. It is one of the key mediators of acute and chronic systemic inflammatory reactions and plays a central role in several autoimmune diseases. A number of approved monoclonal antibodies (mAbs) are widely used to subside these autoimmune diseases. However, there is a high rate of non-responsiveness to treatments with these mAbs. Therefore, it is important to be able to predict responses of the patients in an individualistic manner to these therapeutic antibodies before administration. In the present study, we used in silico tools to explore the effects of missense variants in the respective epitopes of four therapeutic anti-TNFA mAbs—adalimumab (ADA), certolizumab pegol (CZP), golimumab (GLM), and infliximab (IFX)—on their interactions with TNFA. Results The binding affinities of CZP and ADA to corresponding epitopes appear to be reduced by four (TNFAR131Q, TNFAE135G, TNFAR138Q, and TNFAR138W) and two (TNFAG66C and TNFAG66S) variants, respectively. The binding of GLM and IFX appears to be affected by TNFAR141S and TNFAR138W, respectively. TNFAG66C and TNFAG66S may be associated with autoimmune diseases, whereas TNFAE135G, TNFAR138W, and TNFAR141S may be pathogenic per se. Conclusion These variants may contribute to the observed inter-individual variability in response to anti-TNFA mAbs treatments and be used as markers to predict responses, and thus optimize therapeutic benefits to the patients.

Certolizumab-induced lichenoid eruption in a patient with rheumatoid arthritis

Certolizumab is a monoclonal antibody against tumour necrosis factor-alpha (TNF-α) commonly used in rheumatologic conditions such as rheumatoid arthritis. Skin rashes are an uncommon side effect with few cases of lichenoid drug eruption reported in the literature. We describe a patient with rheumatoid arthritis who presented 6 weeks after initiating certolizumab pegol. Physical examination showed pink-to-violaceous papules on her upper and lower extremities. Biopsy confirmed a lichenoid drug eruption. The medication was discontinued and she was treated with topical steroids and a calcineurin inhibitor, with resolution of her lesions. Clinicians should be cognizant of such adverse reactions to TNF-α inhibitors and keep drug-induced lichenoid eruptions on the differential. Lichenoid eruptions induced by certolizumab pegol may affect the skin and/or mucous membranes. While most cases occur within weeks to months of starting therapy, eruptions may occur years after treatment initiation, underscoring the importance of a thorough review of medications.

Impact of Non-Persistence on Healthcare Resource Utilization and Costs in Patients With Immune-Mediated Rheumatic Diseases Initiating Subcutaneous TNF-Alpha Inhibitors: A Before-and-After Study

Rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis are chronic progressive immune-mediated rheumatic diseases (IMRD) that can cause a progressive disability and joint deformation and thus can impact in healthcare resource utilization (HCRU) and costs. The main outcome of the study was to assess the effect of non-persistence to treatment with subcutaneous tumor necrosis factor-alpha inhibitors (SC-TNFis) on HCRU costs in naïve patients with IMRD who started treatment with adalimumab, etanercept, golimumab or certolizumab pegol during 12 months after initiation of treatment. The impact of persistence and non-persistence of SC-TNFis on HCRU costs was compared between 12 months before and 12 months after initiating SC-TNFis. Persistence was defined as the duration of time from initiation to discontinuation of therapy. The study was conducted in an acute care teaching hospital in Barcelona, Spain. Data for the period between 2015 and 2018 were extracted from the hospital cost management control database. HCRU costs comprised outpatient care, outpatient specialized rheumatology care, in-patient care, emergency care, laboratory testing and other non-biological therapies. The study population included 110 naïve SC-TNFis patients, divided into the cohorts of persistent (n = 85) and non-persistent (n = 25) patients. Fifty-six percent of patients were women, with a mean (standard deviation) age of 47.6 (14.8) years. Baseline clinical features and HCRU costs over the 12 months before the index prescription were similar in the two study groups. Before-and-after differences in mean (standard deviation) HCRU costs were significantly higher in the non-persistence group as compared to the persistence group for outpatient rheumatology care (€110.90 [234.56] vs. €20.80 [129.59], p = 0.023), laboratory testing (−€193.99 [195.88] vs. −€241.3 [217.88], p = 0.025), other non-biological drugs (€3849.03 [4046.14] vs. −€10.90 [157.42], p < 0.001) and total costs (€3268.90 [4821.55] vs. −€334.67 (905.44), p < 0.001). Treatment persistence with SC-TNFis may be associated with HCRU cost savings in naïve IMRD patients. Prescribing SC-TNFis with the best long-term persistence is beneficial.