Can peripheral blood eosinophils predict primary non-response to Infliximab therapy in pediatric Crohn's disease?

Ileocaecal resection versus infliximab for ileal Crohn's disease: retrospective 10-year follow-up of the LIR!C trial.

Intestinal tissue levels of infliximab (IFX) in patients with inflammatory bowel disease (IBD) treated with subcutaneous (SC) therapy have not been previously assessed. To compare serum and colonic tissue IFX concentrations in IBD patients receiving SC versus intravenous (IV) IFX. This observational cross-sectional study included IBD patients on stable SC or IV IFX maintenance therapy undergoing routine follow-up colonoscopy. Clinical activity required elevated CDAI or Mayo score plus ≥1 biomarker (fecal calprotectin >250μg/g or CRP >5mg/L). Blood samples and two colonic biopsies were collected for serum and tissue IFX measurements. Thirty-five patients were included. Serum and tissue IFX concentrations were significantly higher in the SC versus IV group (22μg/mL vs. 9μg/mL, p<0.001; 25μg/g vs. 10μg/g, p=0.002). Serum and colonic tissue IFX levels were positively correlated in both cohorts (IV: r=0.42; p=0.014; SC: r=0.43; p=0.001). Colonic tissue IFX concentrations were higher in patients with mild-moderate endoscopic activity than in those without active disease (p<0.001). Serum and colonic tissue IFX levels both predicted sustained clinical remission, with optimal thresholds of 14.5μg/mL (p=0.015) and 17μg/g (p<0.005), respectively. Colonic tissue IFX showed higher predictive accuracy (AUROC 0.82, p=0.01) than serum (AUROC 0.76, p=0.045). SC IFX achieved significantly higher serum and colonic tissue concentrations than IV IFX. Colonic tissue IFX levels demonstrated superior clinical relevance and may support future tissue-based therapeutic drug monitoring strategies in IBD.

The LIBERTY-CD study demonstrated superior efficacy of subcutaneous infliximab-dyyb over placebo for maintenance therapy in patients with Crohn's disease. This post hoc analysis characterised subgroups of patients with different response levels to subcutaneous infliximab. Group-based trajectory modelling was conducted to deconvolute cohort-level data into individual response trajectories based on longitudinal patient-reported outcomes. Potential predictors of subcutaneous infliximab response were explored using multivariable analyses. Subgroups were compared for clinical, endoscopic, biochemical, and health-related quality of life outcomes; comprehensive disease control (achieving composite endpoints) at week54; pre-dose serum infliximab levels; and safety. Four distinct subgroups of patients were identified: super-responders (rapid and high sustained improvement); fast responders; slow responders; and limited responders (partial improvement). In multivariable analyses, lower baseline body mass index (p = 0.022) and pre-dose serum infliximab levels ≥ 14μg/ml at week10 (p = 0.003) were associated with a super-response. At week54, super-responders showed the highest rates of clinical remission (80.3%; p = 0.002), endoscopic response (63.9%; p = 0.009), health-related quality of life remission (72.1%; p = 0.0002), corticosteroid-free remission (59.1%; p = 0.007), and comprehensive disease control achievement (27.9%; p = 0.014) versus other trajectories. Among groups, super-responders maintained the highest pre-dose serum infliximab levels from week10. Comparable overall safety profiles were observed across groups. Distinct subpopulations with varying responses to infliximab were identified by group-based trajectory modelling using longitudinal symptom data, which may support the development of personalised therapy. Super-responders with rapid and sustained improvements during infliximab therapy were more likely to achieve desirable long-term outcomes. ClinicalTrials. gov identifier, NCT03945019 (08 May2019).

Short- and medium-term safety profiles of anti-TNF therapies are well-established, but data on their long-term safety, especially beyond five years, remain limited. This study aims to compare the risk of adverse events (AEs) in patients on stable anti-TNF therapy for less than five years versus more than five years. A retrospective cohort study was conducted in an outpatient IBD clinic from April 2015 to November 2023. Patients were divided into short-term (less than five years) and long-term (more than five years) therapy groups. AEs were tracked across multiple systems, and time-adjusted risks were compared using multivariable Cox proportional hazards models. We identified 640 patients (785 instances) receiving stable anti-TNF therapy. A total of 82 AEs were reported over 1774 person-years. The AE incidence per 100 person-years was 5.12 in the short-term group and 3.50 in the long-term group with no significant adjusted risk between groups (aHR, 0.62; 95% CI 0.35 to 1.11). However, patients with CD on long-term infliximab therapy signaled a lower risk of AEs compared to short-term users (aHR, 0.33; 95% CI 0.11 to 1.00). Dermatologic events were the most common AEs. Long-term anti-TNF therapy appears to have a similar safety profile to short-term therapy, with no significant increase in overall AE risk. These findings may offer cautious reassurance regarding extended anti-TNF use, particularly in patients with CD on infliximab.

Crohn's disease (CD) in children poses a growing clinical challenge, with increasing incidence and variable response to biologic therapies such as infliximab (IFX). While gut bacterial dysbiosis has been extensively studied, the role of the gut virome in pediatric CD remains largely unexplored. This study provides the first longitudinal characterization of the fecal virome in children with CD undergoing IFX therapy. We reveal distinct viral community patterns, functional alterations, and virus-bacteria interactions in pediatric CD patients. Notably, integration of virome and bacteriome profiles enhances diagnostic accuracy, offering a promising avenue for predictive biomarker development. Furthermore, virome changes may be associated with the IFX treatment outcomes in children with CD. These findings highlight the gut virome as a critical but overlooked dimension of host-microbiome interactions in pediatric CD, with potential implications for personalized therapy and mechanistic understanding of treatment resistance.

Behçet's disease (BD) is a multisystem inflammatory disorder in which innate immune dysregulation has been increasingly recognised as a key pathogenic feature, and MEFV variants have also been implicated in its pathogenesis. We describe the case of a 51-year-old Japanese woman with incomplete BD who developed large-vessel vasculitis during treatment with low-dose glucocorticoids and colchicine. She had a history of recurrent abdominal pain associated with menstruation and two episodes of aseptic meningitis since childhood, but she had never experienced periodic fever. Genetic analysis revealed compound heterozygous MEFV variants (E148Q in exon 2 and M694I in exon 10). An 18F-fluorodeoxyglucose positron emission tomography/computed tomography demonstrated aneurysms of the brachiocephalic and bilateral subclavian arteries with patchy fluorodeoxyglucose uptake, indicating active vasculitis consistent with BD rather than familial Mediterranean fever. Infliximab therapy was initiated for BD-associated vasculitis, resulting in the rapid normalisation of C-reactive protein and successful tapering of prednisolone. This case suggests that MEFV variants may contribute to an autoinflammatory background that predisposing to vascular involvement in BD, even in the absence of clinical familial Mediterranean fever. The association between MEFV variants and vascular involvement in BD remains controversial, and it has not been consistently demonstrated in Japanese populations, where both the clinical features and genetic background of familial Mediterranean fever differ from those of Eastern Mediterranean patients. This case may, therefore, provide further insight into the role of MEFV variants in the pathogenesis of vascular involvement in BD, particularly in Japanese patients.

This pilot, prospective, observational two-center study evaluated the efficacy and safety of subcutaneous infliximab CT-P13 S.C. as a second-line treatment in patients with moderate-to-severe Crohn’s disease who had experienced treatment failure with previous intravenous infliximab or adalimumab therapy. Sustained therapeutic response after switching administration methods was observed in 70% of patients, while plasma infliximab concentrations during subcutaneous administration reached more than three-fold higher levels compared with baseline. Half of the patients who exhibited signs of disease activity at the time of treatment transition achieved complete clinical remission. Treatment was discontinued prematurely in 30% of patients due to lack of efficacy or adverse events.

Anti-tumor necrosis factor treatments for inflammatory bowel disease face challenges like primary nonresponse and secondary loss of response, often due to antidrug antibodies that increase drug clearance. The Fc-gamma receptors type3A (FCGR3A) (rs396991) polymorphism affects infliximab pharmacokinetics and immunogenicity. This study investigates its influence on trough levels, anti-infliximab antibody development, and clinical outcomes in Iraqi ulcerative colitis (UC) patients. This single-center study involved patients on maintenance infliximab therapy who were enrolled. Serum infliximab trough levels and anti-infliximab antibodies (antibodies to infliximab) (free and total) were measured using enzyme-linked immunosorbent assay. Genotyping of the FCGR3A rs396991 polymorphism was performed via polymerase chain reaction amplification and Sanger sequencing. The partial Mayo score assessed disease activity. The significance level of statistics was P < .05. Among 43 patients, those with the CC genotype achieved target infliximab trough levels more frequently (55.6%) than AA (21.1%) or AC (0%) genotypes (P = .005). Median infliximab levels were highest in CC carriers (3.41 µg/mL, P = .022). The AC genotype had a significantly higher prevalence of total anti-infliximab antibodies (53.3%) compared to CC (22.2%) and AA (10.5%) groups (P = .02). Logistic regression confirmed the CC genotype positive association with therapeutic drug levels and lower antibody positivity, while the AC genotype correlated with increased immunogenicity. The FCGR3A rs396991 CC genotype is significantly associated with improved infliximab pharmacokinetics and reduced immunogenicity in UC patients. These findings highlight the potential of FCGR3A genotyping to guide personalized therapeutic strategies and optimize clinical outcomes in UC.

The effectiveness of infliximab in Crohn's disease is often compromised by immunogenicity. Oral low-dose methotrexate may offer a promising strategy to optimize infliximab therapy, yet its real-world effectiveness and safety remain uncertain. This study aimed to compare the effectiveness and safety of infliximab plus oral low-dose methotrexate versus infliximab monotherapy. In this single-center retrospective cohort study, 119 patients with Crohn's disease received either infliximab monotherapy (n = 99) or combination therapy with oral low-dose methotrexate (10-15mg/week; n = 20). The primary outcome was endoscopic remission (Simple Endoscopic Score for Crohn's Disease ≤ 2) at week 26. Propensity score methods, including nearest-neighbor matching and inverse probability of treatment weighting, were used to adjust for confounding. Conditional and weighted logistic regression were used to estimate treatment effects. After propensity score adjustment, combination therapy was associated with a significantly higher rate of endoscopic remission (aOR 3.70, 95% CI 1.16-11.75; P = 0.027). No significant differences were observed in endoscopic response or clinical outcomes. In a pharmacokinetic subgroup, combination therapy resulted in numerically higher infliximab trough concentrations and no detectable anti-drug antibodies (0% vs. 16.7%). Higher trough concentrations were associated with endoscopic remission (P = 0.033). The incidence of elevated liver enzymes was higher in the combination group (20.0% vs. 4.0%), but this difference was not statistically significant after adjustment (P = 0.058). In patients with Crohn's disease, oral low-dose methotrexate combined with infliximab was associated with significantly improved endoscopic remission at week 26 compared to infliximab monotherapy, without a statistically significant increase in adverse events.

ObjectiveAcute severe lower gastrointestinal bleeding (SLGIB) is one of the life-threatening complications of Crohn’s disease (CD) whose therapy is being optimized constantly. We aim to evaluate the therapeutic efficacies and economic benefits of different treatments for acute SLGIB in CD.MethodA multicenter retrospective cohort study was conducted in Hunan Province of China on CD patients with acute SLGIB; here, we analyzed the clinical (hemostatic effects, hemoglobin improvement, rebleeding risk, anti-inflammatory influence, and complications) and economic (duration and cost of hospital stay) characteristics of infliximab, surgical, and traditional hemostatic therapies.ResultsAll three groups showed no obvious signs of bleeding in the first week. The negative conversion rates of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in the infliximab therapy group were significantly higher than those in the other two groups (adjusted-p < 0.05 for both CRP and ESR), while the increase in hemoglobin did not differ significantly among the three groups (p = 0.298). The incidence of post-treatment complications was significantly higher in the surgery (resection) group than the other two groups (adjusted-p < 0.05). Cumulative rebleeding risk was lowest in the infliximab therapy group (p = 0.001 vs. surgery and p = 0.032 vs. traditional therapy). The multivariate COX regression also revealed that surgery [hazard ratio (HR) = 7.270, 95% confidence interval (CI): (1.574, 33.592), p = 0.011] and traditional therapy [HR = 4.395, 95% CI: (1.011, 19.113), p = 0.048] were independently related to higher rebleeding risk than infliximab therapy. The duration and cost of hospital stay of the infliximab therapy group were significantly lower than those of the surgery group (adjusted-p < 0.05) and similar to those of the traditional therapy group (adjusted-p > 0.05).ConclusionCompared to surgery and traditional therapy (such as somatostatins or octreotide), infliximab therapy could control acute SLGIB in CD as well as achieve similar improvement in hemoglobin level with additional anti-inflammatory effects and lower rebleeding risk. Furthermore, infliximab therapy was found to be more economical than surgery.

Inflammatory bowel disease, encompassing ulcerative colitis (UC) and Crohn's disease, is increasing in prevalence in Western populations. Infliximab (IFX) is a standard treatment for severe UC. Evidence suggests combination therapy with IFX and azathioprine (AZA) improves clinical outcomes. However, AZA increases non-Hodgkin lymphoma (NHL) risk. We modeled the cost-effectiveness of combination therapy with IFX and AZA versus IFX monotherapy. We used a Markov model to simulate 25-year-old patients with UC over a 5-year time horizon in eight-week cycles. Patients received monotherapy, combination therapy for all 5years ("continuous combination therapy"), or combination therapy for 1year followed by monotherapy ("one-year combination therapy"). We measured quality-adjusted life years (QALYs) and costs of drug therapy, complications, and NHL. With monotherapy, patients experienced 3.263 QALYs and 6.84 flares; with 1-year combination therapy, 3.349 QALYs and 5.73 flares; and with continuous combination therapy, 3.351 QALYs and 5.67 flares. After 5years, NHL incidence was 0.188% with monotherapy; 0.207% with 1-year combination therapy; and 1.121% with continuous combination therapy. Healthcare costs were $312,500 for monotherapy, $264,700 for 1-year combination therapy, and $265,400 for continuous combination therapy. Results were robust across sensitivity analyses. Combination therapy with IFX and AZA is a cost-saving strategy for moderate-to-severe UC, providing superior outcomes and lower costs compared to IFX monotherapy. Both 1-year and continuous combination therapy achieve comparable health outcomes. Short-term combination therapy may be preferable, as it captures the benefits of improved UC management while avoiding the deleterious effects of long-term exposure to thiopurines.

We retrospectively reviewed 895 patients with Kawasaki disease treated at two Japanese pediatric centers between 2015 and 2024 to assess whether N-terminal pro-brain natriuretic peptide (NT-pro BNP) levels at diagnosis can predict the need for infliximab (IFX) therapy. Patients were divided into (1) the IFX group (n = 35), including patients who received IFX as third-line therapy due to resistance to first- and second-line treatments, including intravenous immunoglobulin, and (2) the non-IFX group (n = 860), including patients who responded to initial therapies. Clinical and laboratory variables were compared between the groups, and predictors of IFX use were analyzed using multivariate logistic regression and receiver operating characteristic (ROC) curves. Multivariate analysis comparing the IFX and non-IFX groups identified older age, lower hemoglobin levels, and higher NT-pro BNP Z-score at diagnosis as independent predictors of later IFX requirement. Additionally, the incidence of coronary arterial lesions did not differ significantly between the groups. ROC analysis demonstrated NT-pro BNP Z-score as a significant predictor (AUC 0.66, p < 0.001), with a cutoff of 2.2 yielding 71.4% sensitivity, 63.3% specificity, 7.3% positive predictive value, and 98.2% negative predictive value. Elevated serum NT-pro BNP Z-score at diagnosis was associated with later IFX use, whereas a low Z-score reliably identified patients unlikely to require IFX. Early assessment incorporating NT-pro BNP may optimize Kawasaki disease therapy and guide the appropriate timing of IFX administration.

Specific human leukocyte antigen (HLA) genotypes, particularly HLA-DQA1*05, have been proposed as predictors for infliximab (IFX) treatment response and immunogenicity in Western populations. However, the evidence regarding the effect of HLA-DQA1*05 remains limited in East Asian populations, including in Japan. Moreover, HLA-DQA1*05 frequency differs substantially from those in Western populations. Comprehensive analyses of the association between HLA alleles and IFX treatment outcomes may contribute to the identification of novel prognostic markers for IFX therapies. We retrospectively analyzed 301 biologic-naïve Japanese patients with inflammatory bowel disease (IBD). IFX persistence was assessed at both 2-digit and 4-digit HLA allele resolutions, and associations with anti-drug antibody levels at 1year after the initiation of IFX therapy were evaluated. At the 2-digit resolution analysis, HLA-DQB1*03 (hazard ratio [HR] = 2.39, p = 1.89E-06) and HLA-DQA1*05 (HR = 1.99, p = 3.91E-04) were significantly associated with early IFX discontinuation. At the 4-digit resolution analysis, HLA-DQB1*03:01 (HR = 2.03, p = 9.42E-05) and HLA-DQA1*05:05 (HR = 2.18, p = 4.42E-05) showed similar associations. All HLA-DQA1*05:05 alleles formed haplotypes with HLA-DQB1*03:01. Importantly, HLA-DQB1*03:01 was also associated with early discontinuation of IFX even when it formed haplotypes with alleles other than HLA-DQA1*05:05. Both HLA-DQB1*03:01 and HLA-DQA1*05:05 were significantly associated with elevated anti-drug antibody levels (p = 3.23E-03 and 3.54E-03, respectively). HLA-DQB1*03:01 encompasses the information of HLA-DQA1*05:05 and serves as a strong genetic predictor of IFX treatment persistence and immunogenicity in Japanese patients with IBD, offering a potential biomarker for personalized therapy.

The prevalence of inflammatory bowel diseases is increasing among the elderly. Older patients with inflammatory bowel disease represent a vulnerable population whose treatment strategies are significantly impacted by comorbidities and frailty. We present the case of a 69-year-old, Hungarian, nonsmoker female patient with a history of elderly-onset inflammatory bowel disease. The patient has longstanding type 2 diabetes (on insulin since 2011) and is being treated for hypertension and hyperlipidemia. In 2011, a diagnosis of left-sided ulcerative colitis was made, presenting with symptoms of fever and bloody diarrhea. Following the ineffectiveness of several conservative treatment modalities, the patient initially underwent adalimumab therapy, exhibiting primary nonresponse. Subsequently, the treatment was switched to vedolizumab, but she later developed secondary loss of response. She was diagnosed with end-stage renal disease and was started on hemodialysis in January 2022. In May 2023, because of severe endoscopic and symptomatic disease activity (endoscopic Mayo score 3, partial Mayo score 6, C-reactive protein 26.0mg/L, hemoglobin 111g/L, albumin 39g/L), infliximab therapy was initiated. We measured serial serum drug and anti-drug antibody concentrations to monitor the efficacy of the therapy and the effect of hemodialysis on drug concentrations. The patient responded to infliximab therapy, leading to clinical remission. Infliximab serum drug concentrations remained unaffected by hemodialysis. This case clearly illustrates the impact of comorbidities and the importance of a multidisciplinary approach in the management of elderly patients with inflammatory bowel disease. We demonstrated that infliximab therapy is effective and safe in the presence of concomitant severe inflammatory bowel disease and end-stage renal disease requiring hemodialysis.

Tonsillar tuberculosis as a manifestation of miliary tuberculosis in a patient with ulcerative colitis on infliximab therapy

Infliximab therapy in a child with Kawasaki disease 2 weeks after receiving rotavirus vaccination.

Abstract Background Acquired hemophilia A (AHA) has never been reported in patients with pediatric inflammatory bowel disease (IBD). Aims We describe a case of AHA occurring in an adolescent with ulcerative colitis treated with infliximab. We hypothesize that in rare circumstances, anti-TNF therapy can trigger factor VIII inhibitor development in patients with IBD. Methods We reviewed the disease course of an adolescent with ulcerative colitis who developed AHA after 3 years of infliximab therapy. A focused literature review was performed to assess reports of inflammatory bowel disease and AHA. Results The patient presented at 14 years of age with a 3-month history of bloody diarrhea and raised serum and fecal biomarkers. His colonoscopy showed a Mayo 2 pancolitis. After a course of oral prednisone, he was commenced on infliximab monotherapy in September 2022. He achieved sustained clinical remission with normal serum and fecal biomarkers. Repeat scope in July 2024 showed endoscopic and histologic remission. Intestinal ultrasound in July 2025 showed transmural remission. In July 2025, he presented with spontaneous bruising and palpable purpura on his legs. Laboratory investigations revealed a prolonged aPTT, factor VIII activity &amp;lt;0.01 IU/mL, and a high-titer inhibitor (49 BU), consistent with AHA. Malignancy, infection, and systemic autoimmune disease were excluded. He was treated with recombinant activated factor VII, emicizumab, high dose prednisone plus rituximab. Infliximab was discontinued. Over four weeks he had no further bruising episodes, factor VIII levels improved (to 0.16 U/mL) and inhibitor titer decreased (to 1 BU). He remains on emicizumab, continues to wean prednisone, and will commence an alternate pathway advanced therapy in the next month. He remains in clinical, serum and fecal biomarker remission with transmural remission on intestinal ultrasound. A Literature review confirmed four adalimumab-associated AHA cases. Infliximab has not previously been associated with AHA. Moreover, there have been no prior pediatric IBD reports of AHA. Conclusions This case represents the first pediatric report of infliximab-associated AHA in ulcerative colitis. It expands the spectrum of paradoxical autoimmune complications of anti-TNF therapy in IBD. Gastroenterologists should suspect AHA in IBD patients presenting with unexplained bleeding and prolonged aPTT, even in the context of disease remission. Early recognition and multidisciplinary management are essential to avoid morbidity and guide safe transition to alternate pathway advanced IBD therapies. Funding Agencies None

Abstract BACKGROUND Sustaining therapeutic exposure aligned with disease control is essential for the long-term success of infliximab (IFX) in inflammatory bowel disease (IBD). The Bayesian Estimate Sustaining Trough (BEST) study evaluated the clinical utility of a precision-guided dosing (PGD) tool and pharmacokinetic (PK) metrics, specifically IFX concentration and clearance (CL), to inform individualized dosing strategies. METHODS Patients with IBD receiving maintenance IFX therapy were prospectively enrolled from November 2023 to January 2025 across three North American centers, representing two academic medical centers and one community-based gastroenterology practice. The PGD tool (PredictrPK IFX Maintenance test) measured current IFX and anti-drug antibody levels, estimated trough concentrations, calculated IFX CL (L/day), and proposed dosing regimens to achieve target exposure. Serum samples were processed by an accredited clinical pharmacokinetics laboratory (Prometheus Laboratories, San Diego, CA). Outcomes included changes in IFX dosing and PRO2-based clinical remission, assessed at each treatment cycle. Statistical analyses included Kruskal-Wallis, Fisher test, and logistic regression. RESULTS Ninety-seven patients were enrolled (Table 1), with 296 specimens analyzed (93% proactively). Most patients were in clinical remission (82%), with 90% of cycles showing trough IFX concentrations ≥10 μg/mL and a low incidence of immunization (3%). Following PGD reporting, IFX therapy was reduced (17 cycles, 82% in remission), continued (238 cycles, 84% in remission), intensified (37 cycles, 70% in remission), or discontinued (4 cycles, 25% in remission). Dose intensification was associated with significantly lower concentrations, while dose continuation and reduction correlated with lower CL (Table 2). Clinical remission was associated with lower CL (median 0.244 L/day [IQR: 0.180-0.308 L/day] vs. 0.279 [IQR: 0.231-0.327 L/day], p = 0.005), with no significant difference in trough concentrations. Patients with CL &amp;lt; 0.248 L/day were 2.7 times more likely to be in remission (95% CI: 1.4–5.2, p &amp;lt; 0.01), with a similar trend for those with concentrations &amp;gt;20 μg/mL (OR = 2.1, p = 0.08). CONCLUSION PGD demonstrated clinical utility in informing individualized IFX therapy for IBD, with dosing decisions aligned to pharmacokinetic profiles and clinical outcomes. CL was a strong predictor of clinical remission, reinforcing its role as a key parameter in therapeutic monitoring. PGD guided adjustments, whether intensification, continuation, or reduction, were associated with distinct PK patterns and remission rates, supporting its value in treatment optimization. Importantly, elevated CL identified a subgroup of patients with adequate drug exposure but suboptimal disease control, likely reflecting persistent inflammatory burden.

Background: Inflammatory activity in rheumatoid arthritis can be determined by normal blood count ratios such as Neutrophil Lymphocyte Ratio (NLR), Platelet Lymphocyte Ratio (PLR), Systemic Immune Inflammation Index (SII), and C-reactive Protein (CRP). Objective: The aim of this research is to determine how these markers change after therapy and whether their pre- and post-treatment differences follow patterns that allow for simple parametric analyses. Methods: A prospective cohort of 52 RA patients (30 females and 22 males) was examined. The patients' blood samples were tested at baseline and at the end of their 6-month Infliximab treatment. Hematologic markers such as NLR, PLR, and SII were calculated from the complete blood count (CBC), and CRP levels were measured. The statistical methods of Shapiro-Wilk (SW), Kolmogorov-Smirnov (KS), and Anderson-Darling (AD) were used, and later, paired t-tests were used to generate statistics where necessary. Results: Post-treatment measurements were consistently lower for all four biomarkers. QQ-plots and formal tests revealed that the differences between findings were essentially normal, allowing for paired t-tests. The mean decreases were as follows: NLR -1.10 (95% CI -1.48 to -0.71), PLR -43.0 (-55.4 to -30.7), SII -299 (-388 to -211), and CRP -11.36 (-13.18 to -9.54), all p < 0.001. CRP showed the greatest drop, with significant decreases in PLR and SII and a moderate decline in NLR, indicating therapy-related attenuation of systemic inflammation. Conclusions: The study shows that six months of infliximab therapy results in a consistent post-treatment decrease in all four biomarkers: NLR, PLR, SII, and CRP. Because the pre-post differences were roughly normal, CRP revealed the greatest decrease, with significant decreases in PLR and SII and a moderate decrease in NLR, consistent with systemic inflammation reduction. When combined, the CBC-derived indices track with CRP and can serve as practical, low-cost markers for monitoring therapy response in RA, despite the single-arm design.