Effectiveness of janus kinase inhibitors in relapsing giant cell arteritis in real-world clinical practice and review of the literature.

BACKGROUND: A substantial proportion of patients with giant cell arteritis (GCA) relapse despite standard therapy with glucocorticoids, methotrexate and tocilizumab. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway is involved in the pathogenesis of GCA and JAK inhibitors (JAKi) could be a therapeutic alternative. We evaluated the effectiveness of JAKi in relapsing GCA patients in a real-world setting and reviewed available literature. METHODS: Retrospective analysis of GCA patients treated with JAKi for relapsing disease at thirteen centers in Spain and one center in United States (01/2017-12/2022). Outcomes assessed included clinical remission, complete remission and safety. Clinical remission was defined as the absence of GCA signs and symptoms regardless of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) values. Complete remission was defined as the absence of GCA signs and symptoms along with normal ESR and CRP values. A systematic literature search for other JAKi-treated GCA cases was conducted. RESULTS: Thirty-five patients (86% females, mean age 72.3) with relapsing GCA received JAKi therapy (baricitinib, n = 15; tofacitinib, n = 10; upadacitinib, n = 10). Before JAKi therapy, 22 (63%) patients had received conventional synthetic immunosuppressants (e.g., methotrexate), and 30 (86%) biologics (e.g., tocilizumab). After a median (IQR) follow-up of 11 (6-15.5) months, 20 (57%) patients achieved and maintained clinical remission, 16 (46%) patients achieved and maintained complete remission, and 15 (43%) patients discontinued the initial JAKi due to relapse (n = 11 [31%]) or serious adverse events (n = 4 [11%]). A literature search identified another 36 JAKi-treated GCA cases with clinical improvement reported for the majority of them. CONCLUSIONS: This real-world analysis and literature review suggest that JAKi could be effective in GCA, including in patients failing established glucocorticoid-sparing therapies such as tocilizumab and methotrexate. A phase III randomized controlled trial of upadacitinib is currently ongoing (ClinicalTrials.gov ID NCT03725202).

Targeting the core program of metastasis with a novel drug combination.

BACKGROUND: We previously reported that metastases are generally characterized by a core program of gene expression that activates tissue remodeling/vascularization, alters ion homeostasis, induces the oxidative metabolism, and silences extracellular matrix interactions. This core program distinguishes metastases from their originating primary tumors as well as from their destination host tissues. Therefore, the gene products involved are potential targets for anti-metastasis drug treatment. METHODS: Because the silencing of extracellular matrix interactions predisposes to anoiks in the absence of active survival mechanisms, we tested inhibitors against the other three components. RESULTS: Individually, the low-specificity VEGFR blocker pazopanib (in vivo combined with marimastat), the antioxidant dimethyl sulfoxide (or the substitute atovaquone, which is approved for internal administration), and the ionic modulators bumetanide and tetrathiomolybdate inhibited soft agar colony formation by breast and pancreatic cancer cell lines. The individual candidate agents have a record of use in humans (with limited efficacy when administered individually) and are available for repurposing. In combination, the effects of these drugs were additive or synergistic. In two mouse models of cancer (utilizing 4T1 cells or B16-F10 cells), the combination treatment with these medications, applied immediately (to prevent metastasis formation) or after a delay (to suppress established metastases), dramatically reduced the occurrence of disseminated foci. CONCLUSIONS: The combination of tissue remodeling inhibitors, suppressors of the oxidative metabolism, and ion homeostasis modulators has very strong promise for the treatment of metastases by multiple cancers.

Therapeutic Drug Monitoring of Pazopanib in Renal Cell Carcinoma and Soft Tissue Sarcoma: A Systematic Review.

BACKGROUND: Pazopanib, an anti-angiogenic multitarget tyrosine kinase inhibitor, has been approved for the treatment of metastatic renal cell carcinoma and soft tissue sarcoma. However, its recommended dose does not always produce consistent outcomes, with some patients experiencing adverse effects or toxicity. This variability is due to differences in the systemic exposure to pazopanib. This review aimed to establish whether sufficient evidence exists for the routine or selective therapeutic drug monitoring of pazopanib in adult patients with approved indications. METHODS: A systematic search of the PubMed and Web of Science databases using search terms related to pazopanib and therapeutic drug monitoring yielded 186 and 275 articles, respectively. Ten articles associated with treatment outcomes or toxicity due to drug exposure were selected for review. RESULTS: The included studies were evaluated to determine the significance of the relationship between drug exposure/Ctrough and treatment outcomes and between drug exposure and toxicity. A relationship between exposure and treatment outcomes was observed in 5 studies, whereas the trend was nonsignificant in 4 studies. A relationship between exposure and toxicity was observed in 6 studies, whereas 2 studies did not find a significant relationship; significance was not reported in 3 studies. CONCLUSIONS: Sufficient evidence supports the therapeutic drug monitoring of pazopanib in adult patients to improve its efficacy and/or safety in the approved indications.

Efficacy and safety of venetoclax-based combination therapy for previously untreated acute myeloid leukemia: a meta-analysis.

PURPOSE: To explore the efficacy and safety of venetoclax-based combination therapy for older patients with newly diagnosed acute myeloid leukemia (AML). METHODS: We performed a systematic review and meta-analysis of clinical trials comparing venetoclax plus hypomethylating agents (HMAs) or low-dose cytarabine (LDAC) with mono-HMAs or LDAC. The random or fixed effects model was applied to the studies based on heterogeneity. Dichotomous data were summarized using the risk ratio (RR) and 95% confidence interval (CI). Continuous variable data were reported as weighted mean differences (WMDs). RESULTS: Nine studies, including a total of 1232 patients, were included in this meta-analysis. Thec complete remission (CR)/complete remission with incomplete hematological recovery (CRi) rate of the venetoclax (Ven) + azacytidine (Aza) group was significantly greater than that of the Aza monotherapy group (RR: 2.42; 95% CI: 1.85-3.15; P < 0.001). Similarly, the CR/CRi rate of the Ven + LDAC group was also significantly greater than that of the LDAC monotherapy group (RR: 2.57; 95% CI: 1.58-4.17; P = 0.00). The same results were observed for OS among these groups. However, the incidence of febrile neutropenia was greater in the Ven + Aza group than in the Ven + Decitabine (Dec) or monotherapy Aza group (RR: 0.69; 95% CI: 0.53-0.90; P = 0.006 and RR: 2.19; 95% CI: 1.58-3.03; P < 0.001, respectively). In addition, the Ven + LDAC group had significantly greater rates of constipation, diarrhea, nausea, and vomiting than the LDAC monotherapy group, with RRs and CIs of 0.61 (95% CI 0.44-0.83, P = 0.002), 1.81 (95% CI 1.22-2.67, P = 0.003), 1.39 (95% CI 1.06-1.82, P = 0.016), and 1.80 (95% CI 1.19-2.72, P = 0.005), respectively. CONCLUSION: Venetoclax combined with azacitidine, decitabine, or LDAC significantly improved the CR/CRi and OS of patients with previously untreated AML. However, venetoclax plus azacitidine or LDAC was more likely to lead to increased febrile neutropenia and gastrointestinal toxicity.

Gastrointestinal Conditions: Peptic Ulcer Disease.

Peptic ulcer disease (PUD) involves ulceration of the mucosa in the stomach and/or proximal duodenum. The main causes are Helicobacter pylori infection and nonsteroidal anti-inflammatory drug (NSAID) use. PUD occurs in 5% to 10% of people worldwide, but rates have decreased by more than half during the past 20 years. This reduction is thought to be because of H pylori management, more conservative use of NSAIDs, and/or widespread use of proton pump inhibitors (PPIs). Common symptoms include postprandial abdominal pain, nausea, vomiting, and weight loss. These symptoms have broad overlap with those of other conditions, making clinical diagnosis difficult. Endoscopy is the gold standard for diagnosis, especially in older patients and those with alarm symptoms, but a test-and-treat strategy (noninvasive test for H pylori and treat if positive) can be used for younger patients with no alarm symptoms. Numerous treatment regimens are available, all of which include PPIs plus antibiotics. As an alternative to PPIs, a new triple therapy with vonoprazan (which blocks acid production) plus antibiotics has been approved and appears to be superior to conventional therapy with PPIs plus antibiotics. At least 4 weeks after treatment, repeat testing for H pylori should be obtained to confirm cure. When possible, NSAIDs should be discontinued; when not possible, antisecretory cotherapy should be considered.

Feasibility, safety, efficacy and potential scaling-up of sofosbuvir-based HCV treatment in Central and West Africa: (TAC ANRS 12311 trial).

Access to Hepatis C treatment in Sub-Saharan Africa is a clinical, public health and ethical concern. The multi-country open-label trial TAC ANRS 12311 allowed assessing the feasibility, safety, efficacy of a specific care model of HCV treatment and retreatment in patients with hepatitis C in Sub Saharan Africa. Between November 2015 and March 2017, with follow-up until mid 2019, treatment-naïve patients with HCV without decompensated cirrhosis or liver cancer were recruited to receive 12 week-treatment with either sofosbuvir + ribavirin (HCV genotype 2) or sofosbuvir + ledipasvir (genotype 1 or 4) and retreatment with sofosbuvir + velpatasvir + voxilaprevir in case of virological failure. The primary outcome was sustained virological response at 12 weeks after end of treatment (SVR12). Secondary outcomes included treatment adherence, safety and SVR12 in patients who were retreated due to non-response to first-line treatment. The model of care relied on both viral load assessment and educational sessions to increase patient awareness, adherence and health literacy. The study recruited 120 participants, 36 HIV-co-infected, and 14 cirrhotic. Only one patient discontinued treatment because of return to home country. Neither death nor severe adverse event occurred. SVR12 was reached in 107 patients (89%): (90%) in genotype 1 or 2, and 88% in GT-4. All retreated patients (n = 13) reached SVR12. HCV treatment is highly acceptable, safe and effective under this model of care. Implementation research is now needed to scale up point-of-care HCV testing and SVR assessment, along with community involvement in patient education, to achieve HCV elimination in Sub-Saharan Africa.

Vonoprazan-based therapies versus PPI-based therapies in patients with H. pylori infection: Systematic review and meta-analyses of randomized controlled trials.

BACKGROUND: This study aims to evaluate the efficacy and safety of vonoprazan-amoxicillin (VA), vonoprazan-amoxicillin-clarithromycin (VAC), vonoprazan-based bismuth-containing quadruple therapy (VBQT), and PPI-based triple (PAC) or quadruple therapy (PBQT) for H. pylori infection with the consideration of duration of therapy and amoxicillin dose (H: high; L: low). MATERIALS AND METHODS: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched for eligible randomized controlled trials (RCTs) up to December 15, 2023. The efficacy outcome was eradication rate, and safety outcomes included the rates of adverse events and treatment discontinuation. RESULTS: Twenty-seven RCTs were included. The pooled eradication rates were 82.8% for VA, 89.1% for VAC, and 91.8% for VBQT, which increased with the higher amoxicillin frequency of administration and extended duration of therapy within each regimen. There were no significant differences in eradication rate when comparing 7-VA versus 7-VAC and 14-VA versus 14-VAC. VA was at least comparable to PAC. The eradication rate did not differ significantly between 10-H-VA or 14-H-VA versus 14-PBQT. 7-L-VAC demonstrated higher eradication rate versus 7-PAC and comparable rate to 14-PAC. 14-VBQT showed higher eradication rates versus 14-PBQT. The adverse events rate was 19.3% for VA, 30.6% for VAC, and 38.4% for VBQT. VA had similar risk of adverse events versus VAC and significantly fewer adverse events compared to PBQT. The treatment discontinuation rate did not differ significantly between treatments. CONCLUSIONS: The eradication rate of VBQT was the highest at above 90% followed by VAC and VA. VA was as effective as VAC and superior to PPI-based therapies with favorable safety, highlighting the potential of VA therapy as a promising alternative to traditional PPI-based therapies. VPZ-based triple or quadruple therapies was more effective than PPI-based therapies. Further studies are needed to establish the optimal treatment regimen especially in the western countries.

PERFECTRA: a pragmatic, multicentre, real-life study comparing treat-to-target strategies with baricitinib versus TNF inhibitors in patients with active rheumatoid arthritis after failure on csDMARDs.

OBJECTIVE: To compare the effectiveness of a strategy administering baricitinib versus one using TNF-inhibitors (TNFi) in patients with rheumatoid arthritis (RA) after conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) failure in a real-life treat-to-target (T2T) setting. METHODS: Patients with biological and targeted synthetic DMARD (b/tsDMARD) naïve RA with disease duration ≤5 years without contraindications to b/tsDMARD were randomised to either TNFi or baricitinib when csDMARD failed to achieve disease control in a T2T setting. Changes in clinical and patient-reported outcome measures (PROMs) were assessed at 12-week intervals for 48 weeks. The primary endpoint was non-inferiority, with testing for superiority if non-inferiority is demonstrated, of baricitinib strategy in the number of patients achieving American College of Rheumatology 50 (ACR50) response at 12 weeks. Secondary endpoints included 28-joint count Disease Activity Score with C reactive protein (DAS28-CRP) <2.6, changes in PROMs and radiographic progression. RESULTS: A total of 199 patients (TNFi, n=102; baricitinib, n=97) were studied. Both study groups were similar. Baricitinib was both non-inferior and superior in achieving ACR50 response at week 12 (42% vs 20%). Moreover, 75% of baricitinib patients achieved DAS28-CRP <2.6 at week 12 compared with 46% of TNFi patients. On secondary outcomes throughout the duration of the study, the baricitinib strategy demonstrated comparable or better outcomes than TNFi strategy. Although not powered for safety, no unexpected safety signals were seen in this relatively small group of patients. CONCLUSION: Up to present, in a T2T setting, patients with RA failing csDMARDs have two main strategies to consider, Janus Kinases inhibitor versus bDMARDs (in clinical practice, predominantly TNFi). The PERFECTRA study suggested that starting with baricitinib was superior over TNFi in achieving response at 12 weeks and resulted in improved outcomes across all studied clinical measures and PROMs throughout the study duration in these patients.

Programmed cell death-1 is involved with peripheral blood immune cell profiles in patients with hepatitis C virus antiviral therapy.

Mutations in the non-structural protein regions of hepatitis C virus (HCV) are a cause of a non-sustained virological response (SVR) to treatment with direct-acting antivirals (DAAs) for chronic hepatitis; however, there are non-SVR cases without these mutations. In this study, we examined immune cell profiles in peripheral blood before and after ombitasvir/paritaprevir/ritonavir treatment and screened for genes that could be used to predict the therapeutic effects of DAAs. Fluorescence-activated cell sorting analysis indicated that the median frequencies of programmed cell death-1-positive (PD-1+) effector regulatory T cells (eTregs), PD-1+CD8+ T cells, and PD-1+Helper T cells were decreased significantly in SVR cases, but without significant changes in non-SVR cases. The frequency of PD-1+ naïve Tregs was significantly higher in the SVR group than in the non-SVR group before and after treatment. Similar results were found in patients treated with other DAAs (e.g., daclatasvir plus asunaprevir) and supported an immune response after HCV therapy. RNA-sequencing analysis indicated a significant increase in the expression of genes associated with the immune response in the SVR group, while genes related to intracellular and extracellular signal transduction were highly expressed in the non-SVR group. Therefore, we searched for genes associated with PD-1+ eTregs and CD8+ T cells that were significantly different between the SVR and non-SVR groups and found that T-box transcription factor 21 was associated with the non-SVR state. These results indicate that PD-1-related signaling pathways are associated with a non-SVR mechanism after DAAs treatment separate from mutation-related drug resistance.

Evaluating zanubrutinib for the treatment of adults with chronic lymphocytic leukemia or small lymphocytic lymphoma.

INTRODUCTION: This review evaluates zanubrutinib as a treatment option for adults with chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). Zanubrutinib, a covalent BTK (Bruton's tyrosine kinase) inhibitor, was recently approved by the US FDA based in part on head-to-head data demonstrating improved efficacy and safety compared to ibrutinib. AREAS COVERED: The review discusses the efficacy, safety, and comparative advantages of zanubrutinib, highlighting its safety profile compared to other BTK inhibitors. It also addresses the unmet needs of current therapies in CLL/SLL and provides an overview of competitor compounds and ongoing research in BTK inhibition. EXPERT OPINION: Zanubrutinib, the first BTK inhibitor to demonstrate superior efficacy and safety compared to another BTK inhibitor in CLL, is likely to be widely adopted due to its high-quality data and ease of use. Looking ahead, pirtobrutinib, a novel non-covalent BTK inhibitor, has shown promise in heavily pretreated CLL patients, including those unresponsive to covalent inhibitors, with ongoing phase 3 trials comparing it against ibrutinib. The field is also exploring time-limited therapies like the combination of ibrutinib and venetoclax, with ongoing trials evaluating different combinations to optimize efficacy and minimize toxicity, indicating a promising future for combination therapies in CLL treatment.

Camrelizumab plus famitinib in previously chemo-immunotherapy treated patients with advanced NSCLC: results from an open-label multicenter phase 2 basket study.

BACKGROUND: The combination of immune checkpoint inhibitors and antiangiogenic agents has been effective in treating multiple cancers. This was further explored in an open-label, multicenter phase 2 basket study (NCT04346381), which evaluated the antitumor activity and safety of camrelizumab (an anti-PD-1 antibody) plus famitinib (a receptor tyrosine kinase inhibitor) in patients with advanced solid tumors. We herein report the findings from the cohort of advanced NSCLC patients who progressed after treatment with platinum-doublet chemotherapy and immunotherapy. METHODS: Eligible patients were enrolled and treated with camrelizumab (200 mg once every 3 weeks via intravenous infusion) and oral famitinib (20 mg once daily). The primary endpoint was the objective response rate (ORR). Secondary endpoints included the disease control rate (DCR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Forty patients were enrolled in this cohort, with a median follow-up duration of 11.5 months. Three patients (7.5%) achieved a partial response, and 29 patients (72.5%) achieved stable disease. The ORR and DCR with this combination regimen were 7.5% (95% CI, 1.6-20.4) and 80.0% (95% CI, 64.4-90.9), respectively. The median DoR was 12.1 months (95% CI, 10.3-not reached). The median PFS was 5.4 months (95% CI, 4.1-7.5), and the median OS was 12.1 months (95% CI, 9.1-16.7). The estimated 12-month OS rate was 51.5% (95% CI, 34.9-65.9). The most frequent grade 3 or higher treatment-related adverse events occurring in more than 5% of patients included hypertension (27.5%), palmar-plantar erythrodysesthesia syndrome (10%), decreased neutrophil count (10%), and proteinuria (7.5%). CONCLUSION: Camrelizumab plus famitinib demonstrated favorable benefits in PFS and OS, along with manageable safety profiles, in patients with advanced NSCLC who progressed after platinum-doublet chemotherapy and immunotherapy. This finding warrants further exploration.

The beneficial effects of neutrophil elastase inhibitor on gastrointestinal dysfunction in sepsis.

To investigate the effects of neutrophil elastase inhibitor (sivelestat sodium) on gastrointestinal function in sepsis. A reanalysis of the data from previous clinical trials conducted at our center was performed. Septic patients were divided into either the sivelestat group or the non-sivelestat group. The gastrointestinal dysfunction score (GIDS), feeding intolerance (FI) incidence, serum levels of intestinal barrier function and inflammatory biomarkers were recorded. The clinical severity and outcome variables were also documented. A total of 163 septic patients were included. The proportion of patients with GIDS ≥2 in the sivelestat group was reduced relative to that in the non-sivelestat group (9.6% vs. 22.5%, p = 0.047) on the 7th day of intensive care unit (ICU) admission. The FI incidence was also remarkably reduced in the sivelestat group in contrast to that in the non-sivelestat group (21.2% vs. 37.8%, p = 0.034). Furthermore, the sivelestat group had fewer days of FI [4 (3, 4) vs. 5 (4-6), p = 0.008]. The serum levels of d-lactate (p = 0.033), intestinal fatty acid-binding protein (p = 0.005), interleukin-6 (p = 0.001), white blood cells (p = 0.007), C-reactive protein (p = 0.001), and procalcitonin (p < 0.001) of the sivelestat group were lower than those of the non-sivelestat group. The sivelestat group also demonstrated longer ICU-free days [18 (0-22) vs. 13 (0-17), p = 0.004] and ventilator-free days [22 (1-24) vs. 16 (1-19), p = 0.002] compared with the non-sivelestat group. In conclusion, sivelestat sodium administration appears to improve gastrointestinal dysfunction, mitigate dysregulated inflammation, and reduce disease severity in septic patients.

Vonoprazan causes symptomatic improvement in non-erosive gastroesophageal reflux disease: A systematic review and meta-analysis.

OBJECTIVE: To evaluate the efficacy and safety of vonoprazan therapy as compared to conventional proton pump inhibitors (PPIs) or no vonoprazan for non-erosive esophagitis. METHODS: A thorough search was conducted across databases. The primary outcome was to determine the mean variance in the gastroesophageal reflux disease (GERD) score after vonoprazan treatment. Secondary outcomes comprised alterations in the scores for epigastric pain and post-prandial distress, the proportion of patients displaying improvement, and the occurrence of adverse events. Pooled mean differences and relative risks were determined utilizing random effects models. RESULTS: A total of 1,944 articles were screened and nine of them were included. As compared to PPI or no vonoprazan therapy, vonoprazan treatment led to a significant reduction in the GERD score [mean difference: -3.88 (95 % CI: -5.48, -2.28), p < 0.01, i2=95 %]. As compared to PPI or no vonoprazan therapy, vonoprazan treatment led to a significant reduction in the epigastric pain score [mean difference: -3.02 (95 % CI: -5.41, -0.63), p = 0.01, i2=75 %] and post-prandial distress score [mean difference: -2.82 (95 % CI: -3.51, -2.12), p < 0.01, i2=0 %] (all moderate GRADE evidence). Vonoprazan therapy was found to be safe. CONCLUSION: Treatment with vonoprazan could significantly improve symptoms in patients with non-erosive esophagitis or non-erosive GERD.

Pronounced benefits of JAK inhibition with baricitinib in COVID-19 pneumonia in obese but not lean subjects.

OBJECTIVE: Obesity and age are strongly linked to severe COVID-19 pneumonia where immunomodulatory agents including Janus kinase inhibitors have shown benefits but the efficacy of such therapy in viral pneumonia is not well understood. We evaluated the impact of obesity and age on survival following baricitinib therapy for severe COVID-19. METHODS: A post hoc analysis of the COV-BARRIER multicentre double-blind randomised study of baricitinib versus placebo (PBO) with an assessment of 28-day mortality was performed. All-cause mortality by day 28 was evaluated in a Cox regression analysis (adjusted to age) in three different groups according to body mass index (BMI) (<25 kg/m2, 25-30 kg/m2 and >30 kg/m2) and age <65 years and ≥65 years. RESULTS: In the high BMI group (>25 kg/m2), baricitinib therapy showed a significant survival advantage compared with PBO (incidence rate ratio (IRR) for mortality by day 28 0.53 (95% CI 0.32 to 0.87)) and 0.66 (95% CI 0.46 to 0.94) for the respective <65 years and ≥65 years, respectively. The 28-day all-cause-mortality rates for BMI over 30 were 5.62% for baricitinib and 9.22% for PBO (HR=0.6, p<0.05). For BMI under 25 kg/m2, irrespective of age, baricitinib therapy conferred no survival advantage (IRR of 1.89 (95% CI 0.49 to 7.28) and 0.95 (95% CI 0.46 to 1.99) for <65 years and ≥65 years, respectively) ((mortality 6.6% baricitinib vs 8.1 in PBO), p>0.05). CONCLUSION: The efficacy of baricitinib in COVID-19 pneumonia is linked to obesity suggesting that immunomodulatory therapy benefit is associated with obesity-associated inflammation.

Janus kinase inhibitors in the treatment of pyoderma gangrenosum: case report and review.

Pyoderma gangrenosum (PG) is a rare inflammatory dermatologic condition with neutrophilic infiltration of the skin that causes pustules and ulcerations. Janus kinase (JAK) inhibitors are immunomodulating agents that have been recently described in the literature as an effective treatment for PG. We describe a patient with PG on the lower extremities successfully treated with baricitinib. We also conducted a narrative review of the literature of PG patients treated with JAK inhibitors who were refractory to other treatments.

Higher infection risk for JAK inhibitors tofacitinib and baricitinib compared to subcutaneous biological DMARDs.

INTRODUCTION: Rheumatoid arthritis (RA) is usually treated with disease modifying antirheumatic drugs (DMARDs), including biological DMARDs (bDMARDs) and more recently, Janus kinase inhibitors (JAKi). Randomized trials suggest similar infection risks for JAKi and bDMARDs, but real-world data are scarce. METHODS: From a nationally representative prescription database, adult RA patients starting a new JAKi or bDMARD between August 1st, 2018, and January 31st, 2021, were included. Prescriptions of antibiotic, antiviral or antifungal medication were used as proxy for infections. Infection incidence rates (IR) were compared between JAKi and bDMARDs and infection risks were estimated using multilevel Poisson regression adjusted for follow-up time and potential confounders and stratified for age < 65 and ≥ 65 years. RESULTS: In 14,989 patients, we identified 20,050 treatment episodes with either JAKi or bDMARDs. The infection IR was significantly higher in JAKi (48/100 patient years) compared bDMARDs (35/100 patient years, adjusted incidence rate ratio (IRR) 1.22, 95% CI 1.12-1.33). More herpes zoster infections were seen in JAKi compared to bDMARDs (adjusted IRR 2.65, 95% CI 1.94-3.60). No significant differences in infection IRs were found comparing JAKi baricitinib and tofacitinib. In older patients, infection IRs were higher, but IRRs were similar between age groups. CONCLUSION: In comparison to bDMARDs, JAKi are associated with a slightly higher infection risk and a higher risk of herpes zoster specifically. In older patients, infection IRs are higher but similar infection risks for JAKi and bDMARDs are observed. No differences in infection risk between tofacitinib and baricitinib were found. Key Points • Compared to bDMARDs, JAKi are associated with a slightly higher infection risk for all ages • An increased risk of herpes zoster in patients who use JAK inhibitors was confirmed • No significant differences in infection incidence were found between tofacitinib and baricitinib.