Modelling the opportunity for cost-savings or patient access with biosimilar adalimumab and tocilizumab: a European perspective.

OBJECTIVES: Biosimilars improve patient access by providing cost-effective treatment options. This study assessed the potential for savings and expanded patient access with increased use of two biosimilar disease modifying anti-rheumatic drugs (DMARDs): (a) approved adalimumab biosimilars and (b) the first tocilizumab biosimilar, representing an established biosimilar field and a recent biosimilar entrant in France, Germany, Italy, Spain, and the United Kingdom (UK). METHODS: Separate ex-ante analyses were conducted for each country, parameterized using country-specific list prices, unit volumes annually, and market shares for each therapy. Discounting scenarios of 10%, 20%, and 30% were tested for tocilizumab. Outputs included direct cost-savings associated with drug acquisition or the incremental number of patients that could be treated if savings were redirected. Two biosimilar conversion scenarios were tested. RESULTS: Savings associated with a 100% conversion to adalimumab biosimilar ranged from €10.5 to €187 million (UK and Germany, respectively), or an additional 1,096 to 19,454 patients that could be treated using the cost-savings. Introduction of a tocilizumab biosimilar provided savings up to €29.3 million in the most conservative scenario. Exclusive use of tocilizumab biosimilars (at a 30% discount) could increase savings to €28.8 to €113 million or expand access to an additional 43% of existing tocilizumab users across countries. CONCLUSION: This study demonstrates the benefits that can be realized through increased biosimilar adoption, not only in an untapped tocilizumab market, but also through incremental increases in well-established markets such as adalimumab. As healthcare budgets continue to face downwards pressure globally, strategies to increase biosimilar market share could prove useful to help manage financial constraints.

Adalimumab induced psoriasis in a Crohn's disease patient: A case report.

Adalimumab is a human monoclonal antibody that selectively targets tumour necrosis factor-alpha (TNF- α), a cytokine involved in the pathogenesis of various inflammatory and autoimmune disorders. Adalimumab has been approved worldwide for the treatment of several chronic immune-mediated diseases, including rheumatoid arthritis, psoriasis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, and juvenile idiopathic arthritis. One of the adverse reactions caused by Adalimumab is psoriasis. This study reports the case of a 37-year-old male with palmoplantar psoriasis triggered by adalimumab for treatment of Crohn's disease. This eruption resisted complete clearance with various potent corticosteroids. The patient was referred back to the treating rheumatologist to possibly change adalimumab to another type of therapy.

The Safety Profiles of Adalimumab, Infliximab, Etanercept, Secukinumab and Ustekinumab in Psoriasis - A 30-month Observational Cohort Prospective Study of Adverse Events in Biologic Therapy.

BACKGROUND: Although biologic agents are very effective, long-term comparative studies demonstrating their safety relative to one another are still lacking. METHODS: A total of 124 patients with psoriasis were followed up for 30 months; 74 received anti-TNF-alpha inhibitors (adalimumab, etanercept, infliximab), 33 were on ustekinumab, and 17 were treated with secukinumab. The rates of adverse events in these groups were recorded and statistically analyzed. RESULTS: Infliximab-treated patients showed a high occurrence of asymptomatic, but increased liver enzymes, fatigue, and respiratory as well as dermatologic infections. Adalimumab-treated patients were more often affected by musculoskeletal disorders and infections of all types. Patients treated with secukinumab presented with higher rates of cardiovascular disorders as well as respiratory and dermatologic infections. The group receiving etanercept was more often diagnosed with musculoskeletal and reproductive disorders, specifically menstrual disorders. The rates of therapy discontinuation and serious adverse events did not reach statistically significant values. CONCLUSION: A higher incidence of adverse events was observed among adalimumab-, and infliximab-treated patients, with ustekinumab found to have the safest profile. Our results demonstrate that a personalized approach, including evaluation of a patient's risk profile, is necessary before commencing a biologic. Further research is warranted to confirm the findings of our study.

NLRP3 (rs10754558) gene polymorphism and tumor necrosis factor alpha as predictors for disease activity and response to methotrexate and adalimumab in psoriasis.

BACKGROUND: Psoriasis has a global prevalence of 1-3%, with variations observed across different ethnic groups and geographical areas. Disease susceptibility and response to anti-tumor necrosis factor-α (TNFα) drugs suggest different genetic regulatory mechanisms which may include NLR family pyrin domain containing 3 (NLRP3) polymorphism. Evaluation of the NLRP3 gene polymorphism, the serum level of CRP and TNFα in psoriasis patients and assessment of the NLRP3 (rs10754558) gene polymorphism, CRP and TNFα with disease severity and their role as biomarkers for response to Methotrexate and Adalimumab in psoriasis. The study had a total of 75 patients diagnosed with psoriasis vulgaris, who were compared to a control group of 75 healthy individuals. RESULTS: There was a highly significant difference in NLRP3 genotypes and alleles distribution between psoriasis patients and controls (P = 0.002,0.004). The heterozygote genotype GC (OR = 3.67,95%CI:1.75-7.68, P = 0.0006), was linked with increased risk of psoriasis. Additionally, The GC genotype was significantly associated with nonresponse to psoriasis therapy (OR = 11.7,95%CI:3.24-42.28, P = 0.0002). Regarding serum CRP and TNFα levels, there was a highly statistically significant difference between psoriasis patients and controls (P < 0.0001), and there was also a highly statistically significant difference between responders and non-responders in psoriasis patients regarding PASI 50 (P < 0.0001). CONCLUSIONS: The NLRP3 (rs10754558) genotypes GC was associated with the severe form of psoriasis and with nonresponse to psoriasis medication. Therefore, NLRP3 (rs10754558) gene polymorphism is an important prognostic biomarker in psoriasis patients. The serum TNFα can be used as a predictor for response to therapy in psoriasis patients. More research for evaluation of role of the NLRP3 gene polymorphism in the genetic risks and treatment outcomes associated with psoriasis is still required.

Merkel cell carcinoma associated with TNF inhibitor therapy: a systematic review of case reports.

A rare neuroendocrine skin cancer called Merkel cell carcinoma (MCC) primarily affects elderly people. The objective of this study is to comprehensively review the impact of immunosuppressive medications, particularly TNF inhibitors, on the emergence of MCC. METHODS: PubMed, Web of Science, Science Direct, and Cochrane Library were searched. Study articles were screened by title and abstract at Rayyan Qatar Computing Research Institute, then a full-text assessment was implemented. RESULTS: A total of eight case reports with 9 patients were included. Of the total population, seven were women and only two were men. Their age ranged from 31 to 73 years. More than half the population (5 cases) were being treated for rheumatoid arthritis. All received TNF inhibitors that were associated with the induction of MCC. CONCLUSION: We found that it is essential for physicians to explain potential cancer risks to patients before starting long-term immunosuppressive therapy and to conduct routine checks for MCC and other side effects. TNF inhibitors (infliximab, adalimumab, etanercept, and golimumab) were all associated with MCC development. Women constituted the majority of cases and most were elderly.

Impact of a Patient Support Program on time to discontinuation of adalimumab in Australian adult patients with immune-mediated inflammatory diseases-an observational study.

This observational study evaluated the impact of a sponsor company-provided Patient Support Program (PSP) on discontinuation of adalimumab in adult Australian patients eligible for Pharmaceutical Benefit Scheme (PBS)-reimbursed adalimumab for Rheumatoid Arthritis (RA), Ankylosing Spondylitis (AS), Psoriatic Arthritis (PsA), Crohn's Disease (CD), Ulcerative Colitis (UC), or Hidradenitis Suppurativa (HS). Patients initiating adalimumab between May 2018 and September 2019 were enrolled into two prospective cohorts based on their decision to opt for or decline the PSP (PSP or non-PSP cohorts). In addition, a historical, retrospective Non-PSP cohort was established from the Services Australia 10% PBS dataset by extracting data of patients initiating adalimumab prior to the introduction of adalimumab PSPs and based on adalimumab PBS listing dates (AS: April 2007 to March 2009; PsA/RA: January 2007 to December 2008; CD: January 2009 to December 2010; HS and UC indications not included). Follow-up for all cohorts was 12 months. The primary endpoint was the time to discontinuation, compared between the prospective PSP cohort and the prospective or retrospective Non-PSP cohort. Inverse probability of treatment weighting was used to balance the cohorts. A Cox proportional hazards model indicated no difference in time to discontinuation between the prospective PSP (n = 162) and non-PSP (n = 65) cohorts (HR [95% CI] = 1.256 [0.616-2.563], p = 0.5304). The 12-month adalimumab persistence rates (95% CI) were 78% (69%, 84%) and 82% (67%, 90%), respectively. In contrast, discontinuation was less likely in the prospective PSP (n = 151) compared with the retrospective non-PSP (n = 297) cohort (HR [95% CI] = 0.44 [0.28-0.68], p<0.001). The 12-month persistence rates (95% CI) were 81% (76%, 90%) and 61% (56%, 67%), respectively. Overall, this study suggests that optimal adalimumab persistence can be achieved with either a structured PSP or healthcare support from other sources, but this was not the case more than a decade ago.

Reduction of biologic pricing following biosimilar introduction: Analysis across 57 countries and regions, 2012-19.

OBJECTIVE: To evaluate the impact of the entry of biosimilars on the pricing of eight biologic products in 57 countries and regions. METHODS: We utilized an interrupted time series design and IQVIA MIDAS® data to analyze the annual sales data of eight biologic products (adalimumab, bevacizumab, epoetin, etanercept, filgrastim, infliximab, pegfilgrastim, and trastuzumab) across 57 countries and regions from January 1, 2012, to December 31, 2019. We examined the immediate and long-term changes in biologics ex-manufacturer pricing following the entry of biosimilars to the market. RESULTS: Following the entry of biosimilars, the average price per dose of biologic product was immediately reduced by $438 for trastuzumab, $112 for infliximab, and $110 for bevacizumab. The persistent effect of biosimilars' market entry led to further reductions in price per dose every year: by $49 for adalimumab, $290 for filgrastim, $21 for infliximab, and $189 for trastuzumab. Similarly, we analyzed the impact of biosimilars on four biologics' prices in the US, where the prices of three biologics significantly decreased every year, with filgrastim, pegfilgrastim, and infliximab decreasing by $955, $753, and $104, respectively. CONCLUSIONS: The introduction of biosimilars has significantly reduced the prices of biologics both globally and in the US. These findings not only demonstrate the economic benefits of increasing biosimilar utilization, but also emphasize the importance of biosimilars in controlling healthcare costs. Policies should aim to expand the availability of biosimilars to counteract the exponential growth of medical spending caused by the use of biologics.

Case Report: Effective management of adalimumab-induced acquired hemophilia A with the CyDRI protocol.

Introduction: Acquired Hemophilia A (AHA) is a rare autoimmune disorder characterized by the emergence of inhibitors that specifically target coagulation Factor VIII, frequently resulting in severe bleeding episodes. Methods: We conducted a retrospective analysis of the medical records of a 68-year-old male patient who presented with adalimumab-induced AHA. Results: The patient received adalimumab, a tumor necrosis factor inhibitor antibody, as part of his treatment for rheumatoid arthritis. The patient's clinical journey, characterized by intense bleeding and coagulopathy, was effectively managed with the application of recombinant Factor VIIa (rFVIIa) and the CyDRi protocol. Discussion: The case emphasizes the importance of prompt coagulation assessment in patients with bleeding symptoms receiving disease-modifying therapy for rheumatoid arthritis that includes adalimumab therapy, considering the rare yet life-threatening nature of AHA. Additionally, this report provides an extensive review of the existing literature on drug-induced AHA, with a special emphasis on cases linked to immunomodulatory medications. Through this two-pronged approach, our report aims to enhance understanding and awareness of this severe complication among healthcare providers, promoting timely diagnosis and intervention.

Predictive factors and adalimumab efficacy in managing chronic recurrence Vogt-Koyanagi-Harada disease.

BACKGROUND: This study explores prognostic factors influencing Vogt-Koyanagi-Harada (VKH) disease and observes the efficacy and safety of Adalimumab (ADA) in treating recurrence in Vogt-Koyanagi-Harada (VKH) patients. METHODS: A retrospective study was conducted on all patients diagnosed with VKH disease at Beijing Tongren Hospital between 2020 and 2023. Clinical data included initial and final visual acuity, age, gender, ocular complications, treatment modalities, disease duration, and recurrence frequency. RESULTS: A total of 62 VKH patients were included, comprising 34 in the acute-resolved group and 28 in the chronic-recurrent group. The mean age of patients in the acute-resolved group was 38.29 ± 15.46 years, while the mean age of chronic-recurrent group had a 49.00 ± 16.43 years. Initial best-corrected visual acuity (BCVA) examination at the first visit showed an average BCVA of 0.64 ± 0.29 logMAR in the acute-resolved group and 1.38 ± 0.54 logMAR in the chronic-recurrent group (p = 0.002). During follow-up, ocular complications were observed in 29.4% of the acute-resolved group patients and 41.7% of the chronic-recurrent group patients (P = 0.006). "Sunset glow fundus" was observed in 23.5% of the acute-resolved group and 64.3% of the chronic-recurrent group patients (P = 0.001). Poor initial BCVA (P = 0.046) and the occurrence of "sunset glow fundus" (P = 0.040) were significantly associated with progression to the chronic recurrent phase. Logistic regression analysis revealed that older age at onset (P = 0.042) and the occurrence of "sunset glow fundus" (P = 0.037) were significant predictors for progression to the chronic recurrent phase. ADA significantly reduced anterior chamber inflammatory cells (P = 0.000) and vitreous cavity inflammatory cells (P = 0.001) in the chronic-recurrent group, and markedly decreased the recurrence rate in VKH patients (P = 0.009). CONCLUSION: In comparison to acute-resolved patients, chronic-recurrent patients exhibited poorer initial BCVA and a significantly increased incidence of "sunset glow fundus." Older age at onset and the occurrence of "sunset glow fundus" at diagnosis are crucial predictive factors for VKH patients progressing to the chronic recurrent phase. ADA effectively alleviates refractory VKH disease and is generally well-tolerated.

Cost-Effectiveness of Biosimilars vs Leflunomide in Patients With Rheumatoid Arthritis.

Importance: Among patients with rheumatoid arthritis (RA) who had an inadequate response to methotrexate, a treatment sequence initiated with biosimilar disease-modifying antirheumatic drugs (DMARDs) provides better clinical efficacy compared with conventional synthetic DMARDs recommended by current treatment guidelines; but its cost-effectiveness evidence remains unclear. Objective: To evaluate the cost-effectiveness of the treatment sequence initiated with biosimilar DMARDs after failure with methotrexate vs leflunomide and inform formulary listing decisions. Design, Setting, and Participants: This economic evaluation's cost-effectiveness analysis was performed at a Hong Kong public institution using the Markov disease transition model to simulate the lifetime disease progression and cost for patients with RA, using monetary value in 2022. Scenario and sensitivity analyses were performed to test the internal validity of the modeling conclusion. Participants included patients diagnosed with RA from 2000 to 2021 who were retrieved retrospectively from local electronic medical records to generate model input parameters. Statistical analysis was performed from January 2023 to March 2024. Interventions: The model assesses 3 competing treatment sequences initiated with biosimilar infliximab (CT-P13), biosimilar adalimumab (ABP-501), and leflunomide; all used in combination with methotrexate. Main Outcomes and Measures: Lifetime health care cost and quality-adjusted life-years (QALYs) of the simulated cohort. Results: In total, 25 099 patients with RA were identified (mean [SD] age, 56 [17] years; 19 469 [72.7%] women). In the base-case analysis, the lifetime health care cost and QALYs for the treatment sequence initiated with leflunomide were US $154 632 and 14.82 QALYs, respectively; for biosimilar infliximab, they were US $152 326 and 15.35 QALYs, respectively; and for biosimilar adalimumab, they were US $145 419 and 15.55 QALYs, respectively. Both biosimilar sequences presented lower costs and greater QALYs than the leflunomide sequence. In the deterministic sensitivity analysis, the incremental cost-effectiveness ratio (US$/QALY) comparing biosimilar infliximab sequence vs leflunomide sequence and biosimilar adalimumab sequence vs leflunomide sequence ranged from -15 797 to -8615 and -9088 to 10 238, respectively, all below the predefined willingness-to-pay threshold (US $48 555/QALY gain). In the probabilistic sensitivity analysis, the probability of treatment sequence initiated with leflunomide, biosimilar infliximab, and biosmilar adalimumab being cost-effective out of 10 000 iterations was 0%, 9%, and 91%, respectively. Conclusions and Relevance: In this economic evaluation study, the treatment sequences initiated with biosimilar DMARDs were cost-effective compared with the treatment sequence initiated with leflunomide in managing patients with RA who experienced failure with the initial methotrexate treatment. These results suggest the need to update clinical treatment guidelines for initiating biosimilars immediately after the failure of methotrexate for patients with RA.

Outcomes after anti-tumour necrosis factor originator to biosimilar switching in children and young people with juvenile idiopathic arthritis in the UK: a national cohort study.

BACKGROUND: For cost-saving purposes, children and young people with juvenile idiopathic arthritis (JIA) are being switched (for non-medical reasons) from biological originators to biosimilars. Here, we aimed to investigate those who switched from an anti-tumour necrosis factor (TNF) originator to a biosimilar, regarding drug survival and disease activity, compared with a matched cohort who continued the originator. METHODS: This analysis included all patients in the UK JIA Biologics Register switching directly from an anti-TNF originator to a biosimilar of the same product. All patients were matched (age, sex, disease duration, calendar year of when patients started originator therapy, line of therapy, and International League of Associations for Rheumatology [ILAR] category) to patients continuing the originator. For those matched successfully, a Cox proportional hazard model assessed whether drug persistence differed between those who switched compared with those who continued the originator. Overall change in the 71-joint juvenile arthritis disease activity score and the proportion of patients with a clinically important worsening score (by ≥1·7 units) after 6 months was compared between cohorts. This analysis was designed to address a priority research area set by our patient partners. FINDINGS: There were 224 children and young people with non-systemic JIA (139 [62%] were female, and 85 [38%] were male) identified as switching from a biological originator to a biosimilar of the same product from Jan 1, 2017, to July 7, 2023. 143 (64%) patients were originally on adalimumab, 56 (25%) on etanercept, and 25 (11%) on infliximab. Of these, 164 patients were matched successfully to those continuing the originator. There was no evidence that patients switching were more likely to stop treatment compared with those continuing the originator, with a hazard ratio of 1·46 (95% CI 0·93-2·30). Of the 51 patients in the biosimilar group who stopped treatment, 18 (35%) switched back to the originator (14 in the first year), 28 (55%) started a different biological drug, and five (10%) discontinued all treatment by the last follow-up. Of the 87 matched patients with available disease activity, there was no evidence that JADAS-71 worsened more after 6 months, with an odds ratio of 0·71 (95% CI 0·34-1·51; p=0·38). INTERPRETATION: In this matched comparative effectiveness analysis, children and young people with JIA switched from originators to biosimilars. Disease activity was similar between patients switching compared with those continuing the originator. Three quarters of patients were still receiving their biosimilar after 1 year, with switching back to originator uncommon, at only 9% after 1 year, suggesting good tolerability of non-medical switching in this patient population. This information is reassuring to clinicians and patients regarding the effect of non-medical biological switching. FUNDING: British Society for Rheumatology, Versus Arthritis, and National Institutes for Health Research Manchester Biomedical Research Centre.

Sustaining competition for biosimilars on the pharmacy benefit: Use it or lose it.

Congress passed the Biologic Price Competition and Innovation Act of 2009, specifically to offer market competition as a counterweight to the rising costs of biologic medicines. As of April 15, 2024, 49 biosimilars have been approved by the US Food and Drug Administration in 15 biologic categories. Biosimilar competition has been undeniably successful: Through 2022, biosimilars have saved the US health system $23.6 billion, without significant care disruption or reduced quality. Through 2023, adalimumab biosimilar competition has added an additional $6.5 billion to this total, primarily through greater rebates from the reference manufacturer. Despite launching at discounts as great as 85%, adalimumab biosimilars have not been given preferred formulary positioning in the vast majority of cases and have thus gained only 3% of market share through 2023, largely because of payers' and pharmacy benefit managers' preference for rebates over discounts. This situation may negatively influence future biosimilar development, posing a threat to a biosimilar pipeline that represents hundreds of billions in savings over the next 10 years.

Formulary Coverage of Brand-Name Adalimumab and Biosimilars Across Medicare Part D Plans.

This study examines formulary coverage of brand-name adalimumab and biosimilars across Medicare Part D plans.

Fistulising skin metastases in Crohn's disease: a case report and review of the literature.

BACKGROUND: Metastatic Crohn's disease is a rare disorder characterized by various granulomatous skin lesions that occur independently of gastrointestinal tract involvement. However, currently there is no standardized care or specific treatment. Therapeutic approaches include immunosuppressive agents, such as corticosteroids, azathioprine, and monoclonal antibodies targeting inflammatory cytokines like tumor necrosis factor (TNF). CASE PRESENTATION: We present a case of a 29-year-old western European woman with significant blind ending abdominal subcutaneous fistulas and abscesses, who sought evaluation in the dermatology department. Histological examination revealed multiple epithelioid cell granulomas. There was no evidence of infectious or rheumatologic diseases such as sarcoidosis. The tentative diagnosis was metastatic Crohn's disease, which was not related to an intestinal manifestation of the disease. The patient responded to infliximab but had to discontinue it due to an allergic reaction. Subsequent adalimumab treatment failed to induce clinical remission; thus, therapy was switched to ustekinumab, resulting in a positive response. Written informed consent for publication of their clinical details and clinical images was obtained from the patient. For our study more than 1600 publications were screened for cases of metastatic Crohn's disease on PubMed database. 59 case reports with 171 patients were included in the analysis and evaluated for localization, diagnostic and therapeutic approaches, and complications and were summarized in this review. CONCLUSION: The successful ustekinumab treatment of a patient with metastatic Crohn's disease underscores the potential of this minimally investigated therapeutic option, highlighting the need for future treatment guidelines given the increasing prevalence of such cases.

Use of biologics in Chinese pregnant patients with deficiency of interleukin-36 receptor antagonist (DITRA): A case series.

OBJECTIVE: Impetigo herpetiformis (IH) is a rare form of pustular psoriasis which may result in maternal and fetal morbidity and even mortality. Deficiency of interleukin-36 receptor antagonist (DITRA) is the most frequently identified genetic defect of IH. Currently there are no biologics approved for IH despite the revolutionary role of biologics in the treatment of plaque and pustular psoriasis. Anecdotal reports of biologics use in DITRA patients with IH are also limited. CASE REPORTS: We present herein a case series of 6 Chinese IH patients harboring IL36RN gene c.115+6T>C mutation during 8 pregnancies, treated with various biologics, including adalimumab, etanercept and secukinumab. CONCLUSION: Most pregnancy courses were uneventful, except for one woman who had recurrent episodes of decreased fetal heart rate variability after adalimumab injections, which subsided after switching to etanercept. The treatment effectiveness and safety demonstrated in our cases suggested the role of biologics for the treatment of IH in patients with DITRA.

The use of biologics and JAK inhibitors in the management of moderate to severe Hidradenitis Suppurativa treatment: a scoping review.

This scoping review aims to characterize the use of biologics and Janus Kinase inhibitors (JAKi) in the treatment of Hidradenitis Suppurativa (HS), which is a chronic inflammatory condition. A comprehensive literature search was conducted in PubMed/NCBI, Embase, Web of Science databases, and the Clinicaltrials.gov register. The search included interventional trials assessing the use of biologics or JAKi in HS, with no geographic or time restrictions. Secukinumab and adalimumab were identified as the only two drugs approved by the FDA for treating moderate to severe HS in adults. Several other drug classes showed promising results based on clinical studies reviewed. IL-12/23 inhibitor ustekinumab demonstrated improvements in disease severity scores and HiSCR rates in small trials. IL-17 inhibitors such as brodalumab, bimekizumab, and CJM112 showed preliminary positive responses in early-phase clinical studies and case reports. While evidence was mixed, some TNF-α inhibitors such as infliximab provided benefits according to a randomized controlled trial, though etanercept trials yielded non-significant or inconsistent findings. Larger, well-designed studies are required to further establish their efficacy and safety, but biologics and JAKis show potential as alternative treatment options for moderate to severe HS. The findings of this review contribute to the growing interest among patients and to enhancing the understanding of physician's regarding potential alternative therapeutic options for HS and provide a basis for further research in this field.

Hematologic Abnormalities in Patients With Hidradenitis Suppurativa Receiving Adalimumab.

This post hoc analysis of PIONEER I and II randomized clinical trials assesses whether receiving adalimumab is associated with decreased hematologic abnormalities and increased clinical improvement in patients with hidradenitis suppurativa.

Biomarkers predicting the effect of anti-TNF treatment in paediatric and adult inflammatory bowel disease.

OBJECTIVES: Paediatric and adult inflammatory bowel disease (pIBD, aIBD) patients may lose response to anti-tumour necrosis factor (TNF) treatment within the first year. Adult-extrapolated weight-based dosing is incorrect in children, due to age-related pharmacokinetic differences. We investigated biomarkers for initial and maintenance of response to infliximab (IFX) or adalimumab (ADA), comparing pIBD and aIBD patients. METHODS: In this prospective, observational study, pIBD (n = 24) and aIBD (n = 21) patients were included when initiating anti-TNF. Escalation from standard dosing and continued anti-TNF at 12 and 18 months were assessed. Biomarkers included clinical laboratory parameters, faecal calprotectin (FCP) and IFX trough levels (TLs). Plasma proteomics was performed in pIBD. RESULTS: During our study, treatment escalation (in clinical loss of response) occurred more common in pIBD versus aIBD (p = 0.02). We established that IFX therapy escalation in pIBD patients was not due to low infliximab levels. We identified 9 pro-inflammatory proteins that were elevated in patients losing response. CONCLUSION: Anti-TNF exposure-response relationship may be different in pIBD versus aIBD. No biomarkers for maintained response were identified, but 9 inflammatory proteins were of interest as potential predictors for loss of response in pIBD.