Search Results (217)

Background/Objectives: Immune checkpoint inhibitors (ICIs) have changed the treatment landscape for several advanced malignancies, but their use is accompanied by immune-related adverse events, including liver injury. Some cases resemble autoimmune hepatitis (AIH), although many are more accurately described as AIH-like immune-mediated hepatitis rather than classical AIH. This distinction matters, as diagnosis is often based on exclusion and management must balance hepatic recovery against interruption of potentially life-prolonging cancer therapy. This systematic review summarised the clinical phenotype, diagnostic assessment, treatment strategies, treatment response, ICI discontinuation, and rechallenge outcomes in patients with ICI-associated AIH-like liver injury. Methods: A systematic PubMed search was performed for English-language human studies reporting autoimmune hepatitis, AIH-like liver injury, or immune-mediated hepatitis following exposure to ICIs. Eligible studies included case reports, case series, retrospective cohorts, prospective cohorts, and pharmacovigilance-type studies with extractable clinical, treatment, or outcome data. Reviews, guidelines, non-original articles, animal studies, non-English publications, and reports without usable liver injury data were excluded. The review followed PRISMA principles. Risk of bias was assessed using Joanna Briggs Institute tools and summarised with ROBVIS. Given the heterogeneity of study design, diagnostic criteria, treatment definitions, and outcome reporting, formal meta-analysis was not appropriate; results were therefore synthesised descriptively. Results: Twenty-two studies were included, comprising 195 patients with ICI-associated AIH-like or immune-mediated hepatitis. Of these, 140 patients received active treatment, and 133/140 achieved clinical or biochemical recovery with varying therapies. Corticosteroids were the most frequently used first-line therapy, with recovery reported in 102/105 patients treated with corticosteroids alone. Mycophenolate mofetil was the main second-line agent for steroid-refractory disease, with response reported in 9/10 treated patients. Other therapies, including tacrolimus, azathioprine, ursodeoxycholic acid, bezafibrate, tocilizumab, basiliximab, infliximab, budesonide, and double plasma molecular adsorption system with or without plasma exchange, were described only in small numbers or isolated cases. Spontaneous recovery without pharmacological treatment was reported in 19 patients. ICI interruption or discontinuation occurred in 141 patients, and rechallenge was reported in 55 patients after recovery, with no recurrent hepatic toxicity documented in the extracted dataset. Conclusions: ICI-associated AIH-like liver injury is an important immune-related toxicity, but the available literature remains fragmented and methodologically heterogeneous. Most reported patients recovered, particularly with corticosteroids, and MMF appears to be the most consistently used escalation therapy in steroid-refractory cases. However, the strength of evidence is limited by uncontrolled designs, variable terminology, inconsistent diagnostic work-up, and non-standardised outcome definitions. Future studies should separate classical AIH from AIH-like immune-mediated hepatitis, use uniform criteria for severity and response, and report treatment denominators clearly, especially for rechallenge and steroid-refractory disease. Full article

Background/Objectives: We report a case of severe dermatomyositis demonstrating characteristic widespread extraosseous uptake on ^99mTc-methylene diphosphonate (^99mTc-MDP) bone scintigraphy. This study highlights the diagnostic value of this modality in detecting active inflammatory myopathy when conventional muscle biopsy is inconclusive and introduces its novel use for intraoperative gamma-probe-guided biopsy to precisely target metabolically active muscle. This approach may help target metabolically active muscle in heterogeneous idiopathic inflammatory myopathies (IIMs). Case Presentation: A 49-year-old man developed progressive proximal muscle weakness (Medical Research Council grade 2/5 proximally, 5/5 distally) beginning in June 2025 following influenza infection, accompanied by dysphagia, classic dermatomyositis cutaneous manifestations, back pain, and difficulty standing. Laboratory evaluation revealed elevated inflammatory markers (ESR 55 mm/hr, CRP 20 mg/L), leukocytosis (16.58 × 10⁹/L), markedly raised creatine kinase (19,937 IU/L), and troponin T levels. An initial quadriceps muscle biopsy performed on 29 July 2025 was non-diagnostic. Three-phase ^99mTc-MDP scintigraphy (~1110 MBq) demonstrated intense, diffuse extraosseous uptake involving bilateral deltoids (symmetric), biceps and triceps (patchy), paraspinal muscles (longitudinal), gluteal muscles, thighs (quadriceps and hamstrings), and gastrocnemius muscles, with relative suppression of appendicular skeletal uptake on delayed images due to soft-tissue tracer dominance—findings consistent with severe inflammatory myopathy. Following reinjection (~1100 MBq), intraoperative gamma-probe-guided biopsy targeted areas of highest uptake (left quadriceps femoris and distal triceps brachii; intraoperative counts 1300–1400 versus background ~500). Histopathology revealed histiocyte-predominant inflammation with myofibre necrosis and regeneration, sparse CD4⁺ T-cell infiltrates, and absence of fibrosis, consistent with necrotising myopathy. Positive antinuclear antibodies and strong anti-Mi-2 antibodies confirmed the diagnosis of dermatomyositis. Treatment included pulse methylprednisolone followed by oral prednisone taper, methotrexate, azathioprine, intravenous immunoglobulin, and planned rituximab therapy. Discussion: Whole-body ^99mTc-MDP scintigraphy provided a complementary whole-body functional assessment of disease extent, revealing widespread muscular involvement. The novel application of intraoperative gamma-probe-guided biopsy enabled real-time targeting of metabolically active muscle, facilitating targeted sampling after an initial non-diagnostic biopsy and yielding supportive histopathological findings. This dual diagnostic and interventional role demonstrates the technical feasibility of gamma-probe guidance in a diagnostically challenging case of dermatomyositis. Conclusions: In our case, the integration of ^99mTc-MDP scintigraphy with gamma-probe-guided biopsy enabled precise targeting of metabolically active muscle following an initial non-diagnostic biopsy. This multimodal approach may be useful in selected diagnostically challenging cases of severe inflammatory myopathy. Larger studies are needed to evaluate its reproducibility and added value. Full article

Background: Immunosuppressive drugs (ISDs) are essential for preventing organ rejection but have been reported to increase cancer risk with prolonged use. This study compares cancer risk between ISDs used for long-term maintenance after transplantation (T-ISDs) and those prescribed for non-transplant chronic conditions including cell-mediated (C-ISDs) and receptor-mediated (R-ISDs) ISDs. We hypothesized that cancer risk would differ between T-ISDs and both C-ISD and R-ISD groups. Methods: Using the TriNetX database, solid organ transplant recipients treated with tacrolimus (TAC), cyclosporine (CY), rapamycin (RAPA), or mycophenolate (MMF) were compared to propensity-matched R-ISDs (adalimumab, infliximab, etc.) or C-ISDs (methotrexate, azathioprine, etc.) for at least 24 encounters to determine risk of malignancy. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to assess the three-year cancer risk. Results: After matching, T-ISDs were associated with higher malignancy risk compared to both R-ISDs (n = 29,748; HR 2.616, 95% CI 2.427–2.820) and C-ISDs (n = 31,704; HR 1.271, 95% CI 1.195–1.351). Each individual immunosuppressant in the T-ISD cohort was associated with increased cancer risk compared to R-ISDs, while only TAC and CY showed higher risk than C-ISDs (TAC: n = 9846, HR 1.354, 95% CI 1.228–1.492; CY: n = 1801, HR 1.234, 95% CI 1.007–1.512). Organ-specific analyses showed consistent patterns across systems. Conclusions: Overall, T-ISDs are associated with increased malignancy risk compared to R-ISDs and modestly compared to C-ISDs. TAC and CY confer the greatest risk, while MMF demonstrates relatively lower relative risk. These findings underscore the need to individualize ISD regimens to minimize long-term cancer risk. Full article

Background/Objectives: Idiopathic inflammatory myopathies (IIMs) are chronic immune-mediated disorders, causing striated muscle weakness and extramuscular symptoms. Real-world, single-centre data are needed to interpret phenotype patterns and evolving therapies. Methods: A single-centre, retrospective cohort study was conducted at the Rheumatology Clinic of the National Institute of Geriatrics, Rheumatology and Rehabilitation, Warsaw, Poland from 1 January 2022 to 31 December 2025. Data included demographics, IIM subtypes, extramuscular involvement, co-existing Sjögren disease (SD), biopsy results, autoantibodies, and treatment. Due to sample size, descriptive analysis was used. Results: The study included 35 patients (31.4% men). Mean age was 50.7 years; mean body mass index (BMI) was 26.0 kg/m². The cohort consisted of 10 dermatomyositis (DM), one polymyositis (PM), two immune-mediated necrotising myopathy (IMNM), one inclusion body myositis (IBM), 16 anti-synthetase syndrome (ASyS), four juvenile dermatomyositis (JDM), and one clinically amyopathic dermatomyositis (CADM). SD co-occurred in eight cases, including six cases of ASyS. Anti-Jo1 was observed in 13 ASyS cases and one DM. Glucocorticoids (GCSs) were administered in all patients for induction in addition to cyclophosphamide (28.6%), mycophenolate mofetil (MMF) (51.4%), and methotrexate (MTX) (17.1%). Maintenance therapy included MTX (20%), MMF (31.4%), rituximab (34.3%), azathioprine (AZA) (42.9%), and others. Two DM, two JDM, and one ASyS patient received JAK inhibitors, one DM and one JDM anifrolumab, one IBM sirolimus, and four patients with interstitial lung disease (ILD) nintedanib. Conclusions: This Polish single-centre cohort shows effective use of novel therapies for IIM. Sirolimus, JAK inhibitors, and nintedanib were effective. Co-occurrence of SD in ASyS patients requires further research. Full article

Background and Objectives: While interleukin-1 inhibitors represent the standard of care for refractory idiopathic recurrent acute pericarditis, current guidelines also endorse conventional immunosuppressive (IS) agents as potential alternatives. The use of conventional IS agents is particularly relevant in specific clinical scenarios, such as systemic immune-mediated disease (SID)-associated pericarditis. However, existing evidence regarding their efficacy and safety for pericarditis treatment remains fragmented, deriving exclusively from case reports, case series, and small monocentric observational studies. Our aims are: To characterize the clinical and diagnostic profiles of patients with pericarditis treated with conventional IS agents and to evaluate the therapeutic efficacy and safety of such agents. Materials and Methods: A systematic review was conducted in accordance with PRISMA guidelines. Major electronic databases were searched from January 1970 to March 2026 for case reports, case series, and observational studies detailing the use of conventional IS therapies for pericarditis. Clinical and therapeutic data, including specific IS indications and dosing regimens, were systematically extracted. Results: The final analysis included 39 reports comprising 75 patients (60% female; median age 36.0 years). The underlying pericarditis aetiology was predominantly SID-related (53%, n = 40) or idiopathic/presumed viral recurrent disease (40%, n = 30). The most frequently prescribed first-line IS agents were azathioprine (44%) and methotrexate (25%). Across published reports, IS therapy was described as achieving pericarditis clinical resolution in all cases and facilitated corticosteroid withdrawal in 72% of patients. Overall, pericarditis recurrence while on IS therapy occurred in only 10% of the cohort. Adverse events requiring IS withdrawal were rare (n = 2, 3%). Conclusions: Conventional IS agents appear effective and generally well tolerated in the published literature on SID-associated and isolated recurrent pericarditis. These findings reinforce the clinical utility of conventional IS therapies as a viable, steroid-sparing strategy when targeted biologic therapies lack sufficient investigation. Full article

Background and Objectives: Despite surgical intervention for remission, recurrence is nearly inevitable in patients with Crohn’s disease (CD). While several maintenance therapies are available, the optimal strategy for preventing postoperative recurrence remains uncertain. Materials and Methods: This systematic review and network meta-analysis included placebo-controlled or head-to-head randomized controlled trials (RCTs) from MEDLINE, Embase, and Cochrane Central up to 4 July 2024. Studies assessed maintenance therapies for CD after curative resection. Data were extracted from intention-to-treat (ITT) and per-protocol (PP) analyses separately. The primary outcomes were endoscopic and clinical relapse. A Bayesian network meta-analysis provided risk ratios (RRs) and 95% confidence intervals (CIs). This study is registered with PROSPERO (CRD42024629013). Results: From 1492 screened records, 45 randomized controlled trials met the inclusion criteria. Compared with placebo, clinically significant prevention of clinical recurrence was achieved with adalimumab (RR = 0.17; GRADE High), nitroimidazoles (RR = 0.35; High), infliximab (RR = 0.59; Moderate), thiopurine analogs (RR = 0.41; Moderate), and high-dose mesalamine (RR = 0.74; High), while azathioprine-metronidazole combination therapy demonstrated superior efficacy to azathioprine monotherapy. For endoscopic recurrence mitigation, therapeutic efficacy was confirmed for adalimumab (RR = 0.24; Low), infliximab (RR = 0.32; Moderate), vedolizumab (RR = 0.36; Low), and thiopurine analogs (RR = 0.64; Moderate). Conclusions: This network meta-analysis establishes pharmacological hierarchies for preventing postoperative Crohn’s disease recurrence. Adalimumab is the most effective monotherapy for clinical recurrence prevention, while combination therapies of adalimumab/azathioprine plus nitroimidazole show superior efficacy. For endoscopic recurrence prevention, adalimumab also ranks as the most effective intervention. These findings guide therapy selection but require validation for newer agents through randomized trials. Full article

Rheumatoid arthritis (RA) is a systemic autoimmune disease that can involve the ocular surface and deeper ocular tissues, leading to a spectrum of ophthalmic manifestations ranging from dry eye disease to vision-threatening inflammation, such as scleritis and peripheral ulcerative keratitis (PUK). This paper presents the results of a narrative review conducted using PubMed and Google Scholar from database inception to March 2026. Eligible publications describing clinical features and management of RA-associated ocular disease were synthesized, and no unpublished data were included. According to the literature, dry eye disease (DED) is the most frequent ocular manifestation of RA, and it is primarily managed with lubrication and topical anti-inflammatory therapies, including cyclosporine and lifitegrast. Additional options for refractory disease include neurostimulation and evaporation-targeted therapy. Scleritis and PUK are less common but represent severe inflammatory complications that generally require systemic immunosuppression. Conventional management includes systemic corticosteroids and steroid-sparing agents such as methotrexate (MTX), azathioprine (AZA), cyclophosphamide (CYC), and mycophenolate mofetil (MMF) in aggressive cases. Escalation to biologic disease-modifying antirheumatic drugs (bDMARDs), specifically tumor necrosis factor-alpha (TNF-α) inhibitors and rituximab (RTX), is supported for refractory scleritis and corneal melt, although evidence is largely observational. Among anti-TNF agents, monoclonal antibodies, such as infliximab and adalimumab, appear more effective than etanercept for ocular inflammation. Rituximab is preferred for vasculitis-associated or refractory disease, and Janus Kinase (JAK) inhibitors represent an emerging option requiring careful safety monitoring. Evidence for DED therapies includes randomized controlled trials (RCTs), whereas data for RA-associated scleritis and PUK are largely derived from registries, case series, and case reports. Prospective studies with standardized ocular outcomes are needed to refine treatment algorithms and compare the effectiveness of biologic versus targeted synthetic agents. Full article

Autoimmune hepatitis (AIH) is a chronic immune-mediated liver disorder that, without treatment, can advance to fibrosis and cirrhosis. Although standard regimens with corticosteroids and thiopurines have significantly improved survival, many patients still experience relapses and drug-related toxicity, highlighting the urgent need for alternative strategies. Recent studies underscore AIH’s multifactorial nature, revealing intricate interactions among genetic susceptibility, environmental triggers, and dysregulated immune responses. Next-generation diagnostics, ranging from novel biomarkers to high-resolution imaging, are enhancing early detection and more precise disease classification. At the same time, multi-omics analyses and artificial-intelligence-based models are refining predictions of disease trajectory and therapeutic response. On the treatment horizon, investigational options such as targeted immunomodulators, B-cell–depleting therapies, and cell-based interventions aim to achieve durable remission while minimizing adverse effects. This review critically appraises these advances and explores how integrating epidemiological insights with cutting-edge research in pathogenesis, diagnostics, and therapy could pave the way for more personalized and effective management of AIH. Full article

Background/Objectives: Growing evidence suggests that disruption of circadian rhythms contributes to the pathogenesis of inflammation and inflammatory bowel disease; however, clinical data linking circadian gene variants to ulcerative colitis remain limited. In this study, we aimed to investigate associations between key circadian rhythm gene polymorphisms and clinical and treatment-related characteristics in ulcerative colitis. Methods: A total of 107 patients with ulcerative colitis and 80 healthy controls were included in this single-center cross-sectional study. The BMAL1 rs7950226, CLOCK rs1801260, and CRY1 rs2287161 polymorphisms were analyzed using the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method. Genotype and allele frequency distributions were compared between patients and controls, and associations with clinical characteristics were evaluated within the ulcerative colitis cohort. Results: Genotype distributions of BMAL1 rs7950226 and CLOCK rs1801260 were similar between patients with ulcerative colitis and healthy controls; however, the G allele of BMAL1 was more frequent in patients (p = 0.028). Within the ulcerative colitis cohort, CLOCK rs1801260 genotypes were significantly associated with inflammatory and treatment-related characteristics, with the CC genotype linked to higher C-reactive protein levels (p = 0.021) and the TT genotype associated with increased azathioprine use (p = 0.006). Conclusions: These findings suggest a potential association between circadian rhythm gene variants and clinical features of ulcerative colitis, particularly in relation to inflammatory activity and treatment requirements, and provide preliminary clinical insight that warrants further investigation in larger and longitudinal studies. Full article

Background. Autoimmune sclerosing cholangitis (ASC) is a rare clinical entity characterized by overlapping features of autoimmune hepatitis and primary sclerosing cholangitis. It predominantly affects pediatric patients. Therapeutic management is often complex, requiring a multidisciplinary and individualized approach, especially in the context of associated autoimmune diseases. Case presentation. We present the case of a female patient diagnosed at the age of 10 with ASC, for which immunosuppressive therapy with prednisone, azathioprine (AZA), and ursodeoxycholic acid (UDCA) was initiated, with an initially favorable course. One year later, following a Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection, the patient experienced reactivation of liver disease and subsequently developed ulcerative pancolitis (UC), for which 5-aminosalicylic acid (5-ASA) therapy was initiated. Due to repeated hepatic flares and/or colitis relapses, therapy was escalated successively to mycophenolate mofetil, tacrolimus, and eventually infliximab (IFX). Despite treatment, the liver disease progressed, culminating in liver cirrhosis. Our patient developed portal hypertension and esophageal varices, with two episodes of upper gastrointestinal bleeding requiring endoscopic band ligation. At the age of 14, the patient developed recurrent episodes of non-infectious ulcerative stomatitis. Biopsy of the lesions revealed non-specific chronic inflammation, unrelated to colitis activity (confirmed microscopic remission of UC). By exclusion, an adverse drug reaction was suspected, with AZA being the most likely cause. Following its discontinuation, the lesions resolved. Beyond the physiological and therapeutic aspects, the patient displays marked emotional fragility due to prolonged and repeated hospitalizations (18 out of 60 months), which have impacted treatment adherence. Conclusions. This case highlights the complexity of managing pediatric patients with multiple autoimmune diseases. The necessary combination of immunosuppressive therapies may lead to significant adverse effects and further complicate disease progression. Moreover, psychological components play a crucial role in treatment compliance and therapeutic success, emphasizing the need for an integrated approach that includes specialized psychological support. Full article

Facial vascularized composite allotransplantation (fVCA) is one of the most complex forms of vascularized composite allotransplantation and requires lifelong immunosuppression to ensure graft survival. Despite significant advances in surgical techniques and postoperative care over the past two decades, the true incidence of cutaneous malignancies in fVCA recipients remains poorly characterized due to the limited number of procedures, heterogeneous immunosuppressive protocols, and relatively short follow-up. This narrative review summarizes current evidence on oncologic risk in facial VCA, focusing on the effects of different immunosuppressive regimens and the challenges posed by the high immunogenicity of skin and mucosa. Available data indicate that malignancies, including cutaneous and other neoplasms, occur in approximately 10% of recipients, based on heterogeneous case-series data with immunosuppressive therapies largely extrapolated from solid organ transplantation. Calcineurin inhibitors, corticosteroids, and azathioprine are associated with increased oncologic risk, whereas mycophenolate mofetil and mTOR inhibitors may confer a more favorable profile. Overall, fVCA, unlike solid organ transplantation, is a life-enhancing procedure, highlighting the need for tailored immunosuppressive strategies, rigorous dermatologic surveillance, and further research supported by dedicated registries to better define long-term malignancy risk. Full article

Hepatitis A virus (HAV) infection can occasionally cause acute severe hepatitis. Patients with this disease sometimes need to undergo liver transplantation with immunosuppressants. Although rare, breakthrough HAV infections, despite vaccination, appear to be more common among immunocompromised populations. The effect of immunosuppressants on HAV replication is unclear. In this study, we examined the effects of immunosuppressants on HAV HA11-1299 genotype IIIA replication in human hepatocytes, finding that azathioprine inhibited HAV replication with a half-maximal inhibitory concentration of 0.967 μmol/L. We further examined the effect of azathioprine on the replication of HAV HM175 18f genotype IB using replication-competent or replication-incompetent subgenomic replicon in HuhT7 cells. Azathioprine had significant inhibitory effects on the HAV replication-competent subgenomic replicon compared to the replication-incompetent subgenomic replicon. The effect of azathioprine on the activity of the HAV HM175 18f genotype IB-internal ribosomal entry site (IRES) was investigated in COS7-HAV-IRES cells using a reporter assay. Azathioprine at 1 μmol/L had a significant inhibitory effect on HAV IRES activity but at 0.5 μmol/L had no inhibitory effect. Azathioprine appears to inhibit HAV replication as well as HAV translation. In conclusion, we found that azathioprine inhibits HAV replication in human hepatocytes, meaning that it may be useful for patients with a HAV infection who need to use immunosuppressants. Full article

Background/Objectives: Interstitial pneumonia with autoimmune features (IPAF) is a recently defined entity characterized by interstitial lung disease (ILD) with clinical, serological, and radiological features suggestive of autoimmunity that do not fulfil the criteria for a defined connective tissue disease (CTD). This study aimed to evaluate the clinical characteristics, treatment modalities, and outcomes of patients with IPAF in a tertiary referral center. Methods: We retrospectively analyzed 72 patients who fulfilled the IPAF classification criteria. Demographic, clinical, serological, radiological, pulmonary function, treatment, and survival data were collected and evaluated. Logistic regression analysis was performed to identify factors associated with mortality. Results: The cohort consisted of 62.5% female patients, with a mean age of 62.7 (SD, 10.4) years at diagnosis. The most frequent radiological pattern was nonspecific interstitial pneumonia (83.3%). Raynaud’s phenomenon (6.9%) and arthritis (2.8%) were the most common rheumatological manifestations. Antinuclear antibodies positivity at titers ≥1:320 was observed in 27.8% of patients. Azathioprine was the most frequently prescribed agent (20.8%), followed by mycophenolate mofetil (11.1%). After a median follow-up of 30.1 months (IQR, 52.8), 16 patients (22.22%) died, with a 5-year survival rate of 70%. Glucocorticoid therapy at doses ≥20 mg/day was independently associated with increased mortality (OR 6.13 (95% CI 1.17–32.21). Conclusions: IPAF predominantly affects middle-aged females. Glucocorticoid use at doses ≥20 mg/day was associated with mortality; however, this observational association may reflect underlying disease severity rather than a causal effect of high-dose treatment. Further prospective studies are needed to optimize management strategies in patients with IPAF. Full article

Background/Objectives: Given the clinical limitations of azathioprine (AZA) in treating inflammatory bowel disease, this study developed an AZA-loaded microbiota-modulating and colon-targeted nanoparticle constructed from pectin, Zein, and Eudragit^®S100 (APZE), which was hypothesized to enhance efficacy while reducing toxicity. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established to simultaneously quantify AZA and its metabolites, enabling the investigation of the pharmacokinetic and microbial metabolism differences between APZE and AZA suspension (AZAS). Methods: APZE was characterized, and an LC-MS/MS method was developed for quantifying AZA and its metabolites in multiple matrices. Given the potential of APZE for colon targeting and modulation of the microbiota, which may affect drug absorption, distribution, and microbiota-mediated metabolism, we determined analyte concentrations in rat plasma, tissues, and microbial cultures at different time points following administration of APZE or AZAS. Results: AZA, 6-mercaptopurine (6-MP), 6-methylmercaptopurine (6-MMP), and 6-thioguanine (6-TG) were quantified in positive ion mode, and 6-thiouric acid (6-TU) in negative ion mode. The assay demonstrated excellent accuracy, precision, and stability over the concentration range of 5–1000 ng/mL. Orally administered APZE exhibited higher bioavailability, improved intestinal absorption, and reduced formation of the inactive metabolite 6-TU compared to AZAS. In microbial cultures, AZA was metabolized primarily to 6-MP, and APZE underwent more extensive metabolism to 6-MP than AZAS. Conclusions: This method provides accurate and precise quantification of physiologically relevant concentrations of AZA and its metabolites (6-MP, 6-MMP, 6-TG, and 6-TU), offering a bioanalytical tool for the pharmacokinetic and gut microbiota metabolism studies of AZA formulations. These findings suggest that APZE is a promising drug delivery formulation. Full article

Background/Objectives: Predicting treatment persistence in inflammatory bowel disease (IBD) remains challenging despite a broadened therapeutic arsenal. This study used longitudinal data to assess drug persistence across four biologics for IBD prior to Interleukin (IL)-23 blocker approval. Methods: We retrospectively analyzed IBD outpatients at Goethe University Hospital. Laboratory data and treatment adherence were collected to determine how many patients continued each biological therapy after induction and at 1 year. Results: Of 587 patients, those on azathioprine or mercaptopurine were excluded (focusing on biologics). Four biologicals were analyzed: 280 patients received one of them; 312 (53.2%) had Crohn’s disease and 275 (46.8%) had Ulcerative Colitis. Infliximab (IFX) was given to 93 patients (median 912 days; range 20–5273); at endpoint, 39 (42.4%) remained on IFX. Adalimumab (ADA) was used by 165 patients (median 1051 days; range 48–4458); 87 (52.4%) remained at endpoint. Vedolizumab (VDZ) included 116 patients (median 717 days; range 0–2204); 75 (64.4%) remained at endpoint. Ustekinumab (UST) was given to 62 patients (median 660 days; range 50–1399); 51 (83.6%) remained at endpoint. Some patients were exposed to multiple biologicals, contributing to smaller numbers for newer drugs. When evaluated as a first-line biological, UST (median 787 days) and VDZ (median 756.5 days) had the shortest durations, while TNF-α blockers (ADA, IFX) showed the greatest resistance as first-line therapy. Conclusions: Most patients stayed on their initial therapy after induction and at 1 year. These findings support the sustained use of established biological therapies as cost-effective, steroid-sparing options even after IL-23 approval and may inform patient counseling and long-term pharmacoeconomic considerations. Full article