Effect Of Janus Kinase Inhibitors Research Articles

JAK inhibitors in refractory juvenile rheumatic diseases: Efficacy, tolerance and type-I interferon profiling, a single center retrospective study

Objectives– Janus Kinase inhibitors (JAKi) are a new class of drugs available for pediatric rheumatic diseases.This study aimed to describe the safety and effectiveness of JAKi in these diseases, with a focus on longitudinal interferon-stimulated genes (ISG) assessment. Methods– We present a single-center retrospective study of children with refractory pediatric rheumatic diseases including connective tissue diseases, monogenic type I interferonopathies or juvenile idiopathic arthritis, receiving JAKi. According to physicians’ assessment, treatment effectiveness was classified at 12 months as a complete response in the total absence of disease activity, partial response in case of significant (>50%) but incomplete improvement or no response in the case of non-response or improvement of less than 50% of the clinical and biological parameters. ISG were monitored longitudinally using Nanostring technology. Results- 22 children were retrospectively included in this study, treated either by baricitinib or ruxolitinib. Complete response was achieved at 12 months in 9/22 (41%) patients. 6/22 (27%) patients were non-responders and treatment had been discontinued in five of them. Within the interferon (IFN)-related diseases group, ISG-score was significantly reduced 12 months after JAKi onset (p = 0.0068). At 12 months, daily glucocorticoid doses had been reduced with a median dose of 0.16 mg/kg/day (IQR 0.11; 0.33) (p = 0.0425). 7/22 (32%) patients had experienced side effects, infections being the most common. Increase of the body mass index was also recorded in children in the first 6 months of treatment. Conclusion– JAKi represent a promising treatment of immune-mediated pediatric diseases, enabling to decrease type-I IFN transcriptomic signature in responding patients, especially in the context of juvenile dermatomyositis. JAKi represent steroid-sparing drugs but they induce metabolic changes linked to weight gain, posing a concern in the treatment of young patients and teenagers. More data are required to define the efficacy and safety of JAKi in the management of refractory pediatric rheumatic diseases.

Are There Sex-Related Differences in the Effectiveness of Janus Kinase Inhibitors in Rheumatoid Arthritis Patients?

Background: There is evidence suggesting the existence of sex differences in the effectiveness of specific drug classes for rheumatoid arthritis (RA). Our study stands as the first to elucidate sex-related differences in the effectiveness of Janus kinase (JAK) inhibitors. Methods: The study involved 150 RA patients treated with tofacitinib, baricitinib, upadacitinib, or filgotinib between September 2017 and October 2023. Sex differences in achieving remission and low disease activity (LDA) were identified through logistic regression analyses. Sex disparities in treatment effectiveness survival were evaluated through the Kaplan-Meier estimate, employing the log-rank test for comparison. The Cox model was applied to analyze the variable sex as a potential factor that could influence the maintenance of the JAK inhibitor treatment effectiveness. Results: Concerning the achievement of remission and LDA, no differences were observed between sexes in terms of the 28-joint Disease Activity Score (DAS28) C-reactive protein (CRP), the Clinical Disease Activity Index (CDAI), and the Simplified Disease Activity Index (SDAI). With respect to the DAS28-erythrocyte sedimentation rate (ESR), female patients, compared to males, possessed 70% lower odds of achieving remission (p = 0.018) and 66% lower odds of achieving LDA (p = 0.023). No differences were observed in treatment effectiveness survival between sexes (p = 0.703). Sex was not found to influence the survival of JAK inhibitor treatment effectiveness (p = 0.704). Conclusions: Being a female or male patient does not entail differences in the effectiveness of the JAK inhibitor treatment. Our findings encourage the consideration of a global pool of composite indices (DAS28-ESR/CRP, CDAI, SDAI) to measure RA disease activity, thus individualizing the target value as advocated by the treat-to-target strategy.

Safety and effectiveness of Janus kinase inhibitors in the management of inflammatory bowel disease following liver transplantation.

The management of inflammatory bowel disease (IBD) patients with concurrent liver transplantation is challenging, and data regarding the safety and efficacy of Janus kinase (JAK) inhibitors with anti-rejection medications are required. We report the experience of all liver transplant recipients receiving tofacitinib and/or upadacitinib for IBD across three states in Australia. All liver transplant recipients from the Australian states of Victoria, New South Wales and Tasmania who required tofacitinib or upadacitinib for the treatment of IBD were identified using prospectively maintained liver transplant databases. Patients were followed up until medication cessation or last follow up. Clinical safety and efficacy data were collected. Eight patients (median age 30 years) were included, seven of whom received first-line JAK inhibition with tofacitinib. All patients had failed one or more biologic therapies prior to commencing JAK inhibition, including six patients who had failed two or more agents. JAK inhibition was continued for a median of 17 months, with 143 patient-months of combined follow-up. The anti-rejection medication tacrolimus was prescribed in all patients. Overall, seven (88%) patients achieved clinical remission, including all three patients who were switched from tofacitinib to upadacitinib. One patient required colectomy after 1 month of treatment. There were no other cases of serious infection, venous thromboembolism or major adverse cardiovascular events during follow-up. As the largest case series to-date, these data indicate that combining JAK inhibition with transplant anti-rejection medication may be a safe and clinically effective method of treating IBD in patients with prior biologic failure.

The Effect of JAK Inhibitors on Patient-Reported Outcomes in Psoriatic Arthritis.

Psoriatic arthritis (PsA) is a chronic inflammatory disease that affects the joints and skin of patients with psoriasis. In this review we aimed to summarise the available evidence regarding the effect of Janus kinase inhibitors (JAKi) on patient-reported outcomes (PROs) when used for the management of PsA. We utilised a narrative review approach as we searched the available literature for articles to be included in our study. JAKi have been found to be effective in inducing better PRO responses compared to placebo. These findings have been consistent across various patient populations, including those with active PsA, those with an inadequate response to conventional therapies, and those with comorbidities. The evidence supporting the benefits of JAKi on PROs in PsA is compelling, demonstrating consistent improvements in pain, physical function, fatigue, and quality of life. Numerous studies have demonstrated the the efficacy of JAKi in improving PROs in patients with PsA.

Are JAKis more effective among elderly patients with RA, smokers and those with higher cardiovascular risk? A comparative effectiveness study of b/tsDMARDs in Sweden

ObjectivesTo investigate whether the relative effectiveness of janus kinase inhibitors (JAKis) versus tumour necrosis factor inhibitors (TNFi) or other biological disease-modifying antirheumatic drugs in rheumatoid arthritis differ by the presence...

Risk of major adverse cardiovascular events in patients with rheumatoid arthritis treated with conventional synthetic, biologic and targeted synthetic disease-modifying antirheumatic drugs: observational data from the German RABBIT register

ObjectiveTo estimate the effects of Janus kinase inhibitors (JAKi), tumour necrosis factor inhibitors (TNFi), other biologic(b) or conventional synthetic(cs) disease-modifying antirheumatic drugs (DMARDs) on the risk of major adverse cardiovascular...

Effect of JAK inhibitors on the three forms of bone damage in autoimmune arthritis: joint erosion, periarticular osteopenia, and systemic bone loss

BackgroundThe types of bone damage in rheumatoid arthritis (RA) include joint erosion, periarticular osteoporosis, and systemic osteoporosis. Janus kinase (JAK) inhibitors ameliorate inflammation and joint erosion in RA, but their effect on the three types of bone loss have not been reportedly explored in depth. We aimed to clarify how JAK inhibitors influence the various types of bone loss in arthritis by modulating osteoclastic bone resorption and/or osteoblastic bone formation.MethodsCollagen-induced arthritis (CIA) mice were treated with a JAK inhibitor after the onset of arthritis. Micro-computed tomography (μCT) and histological analyses (bone morphometric analyses) on the erosive calcaneocuboid joint, periarticular bone (distal femur or proximal tibia), and vertebrae were performed. The effect of four different JAK inhibitors on osteoclastogenesis under various conditions was examined in vitro.ResultsThe JAK inhibitor ameliorated joint erosion, periarticular osteopenia and systemic bone loss. It reduced the osteoclast number in all the three types of bone damage. The JAK inhibitor enhanced osteoblastic bone formation in the calcaneus distal to inflammatory synovium in the calcaneocuboid joints, periarticular region of the tibia and vertebrae, but not the inflamed calcaneocuboid joint. All the JAK inhibitors suppressed osteoclastogenesis in vitro to a similar extent in the presence of osteoblastic cells. Most of the JAK inhibitors abrogated the suppressive effect of Th1 cells on osteoclastogenesis by inhibiting IFN-γ signaling in osteoclast precursor cells, while a JAK inhibitor did not affect this effect due to less ability to inhibit IFN-γ signaling.ConclusionsThe JAK inhibitor suppressed joint erosion mainly by inhibiting osteoclastogenesis, while it ameliorated periarticular osteopenia and systemic bone loss by both inhibiting osteoclastogenesis and promoting osteoblastogenesis. These results indicate that the effect of JAK inhibitors on osteoclastogenesis and osteoblastogenesis depends on the bone damage type and the affected bone area. In vitro studies suggest that while JAK inhibitors inhibit osteoclastic bone resorption, their effects on osteoclastogenesis in inflammatory environments vary depending on the cytokine milieu, JAK selectivity and cytokine signaling specificity. The findings reported here should contribute to the strategic use of antirheumatic drugs against structural damages in RA.

Palmoplantar Pustulosis: A Systematic Review of Risk Factors and Therapies.

Palmoplantar pustulosis (PPP) is a chronic, relapsing, inflammatory disease that can occur alone or in association with arthritis. There is still controversy about whether it should be separated from psoriasis or classified as pustular psoriasis. Furthermore, drug-induced paradoxical PPP is a special variant of PPP that differs from classic PPP in several ways. Treatment of PPP is still challenging, and there are a number of treatment-resistant cases. This review summarizes the risk factors for the development of PPP and the currently available treatment modalities. Female sex, smokers or ex-smokers, obesity, thyroid dysfunction, and treatment with a tumor necrosis factor (TNF)-α inhibitor have been identified as risk factors for the disease's development, severity, and course. Topical treatments and phototherapy are effective for some patients and are used as a first-line or adjuvant treatment modality. Conventional treatments including retinoids and fumaric acid show good effects and can increase the efficacy of treatment with psoralen + ultraviolet light therapy (PUVA). Ciclosporin is fast acting, but relapse mostly occurs immediately after cessation. TNF-α inhibitors are efficient, and an even better response can be achieved with IL-17 and IL-23 blockers as well as apremilast. The effect of Janus kinase inhibitors seems to be promising according to case reports, but further investigations with larger cohorts are needed.

Efficacy of Janus kinase inhibitors in adult patients with alopecia areata

Alopecia areata (AA) is a chronic, immune-mediated disorder resulting in localized hair loss due to targeting hair follicle epithelium. The authors aimed to summarize the existing literature on patients with AA who underwent treatment with Janus kinase inhibitors (JAKis) and discuss the current evidence regarding their efficacy and safety. An extensive scientific literature search was conducted between January 1, 2017, and April 16, 2023, using a recognized medical and scientific database. The extracted data were synthesized and analyzed, focusing on the effect of JAKis in reducing hair loss in adult patients with AA. The evidence suggests that oral JAKis such as tofacitinib, ruxolitinib, and Baricitinib show promise in treating AA regarding both efficacy and safety. The group of drugs JAKis are a good treatment option even in severe clinical conditions of AA, further investigation should be taken to consideration including dosage and treatment duration.

Metabolic Profiling of Rheumatoid Arthritis Neutrophils Reveals Altered Energy Metabolism That Is Not Affected by JAK Inhibition.

Neutrophils play a key role in the pathophysiology of rheumatoid arthritis (RA) where release of ROS and proteases directly causes damage to joints and tissues. Neutrophil function can be modulated by Janus Kinase (JAK) inhibitor drugs, including tofacitinib and baricitinib, which are clinically effective treatments for RA. However, clinical trials have reported increased infection rates and transient neutropenia during therapy. The subtle differences in the mode of action, efficacy and safety of JAK inhibitors have been the primary research topic of many clinical trials and systematic reviews, to provide a more precise and targeted treatment to patients. The aim of this study was to determine both the differences in the metabolome of neutrophils from healthy controls and people with RA, and the effect of different JAK inhibitors on the metabolome of healthy and RA neutrophils. Isolated neutrophils from healthy controls (HC) (n = 6) and people with RA (n = 7) were incubated with baricitinib, tofacitinib or a pan-JAK inhibitor (all 200 ng/mL) for 2 h. Metabolites were extracted, and 1H nuclear magnetic resonance (NMR) was applied to study the metabolic changes. Multivariate analyses and machine learning models showed a divergent metabolic pattern in RA neutrophils compared to HC at 0 h (F1 score = 86.7%) driven by energy metabolites (ATP, ADP, GTP and glucose). No difference was observed in the neutrophil metabolome when treated with JAK inhibitors. However, JAK inhibitors significantly inhibited ROS production and baricitinib decreased NET production (p < 0.05). Bacterial killing was not impaired by JAK inhibitors, indicating that the effect of JAK inhibitors on neutrophils can inhibit joint damage in RA without impairing host defence. This study highlights altered energy metabolism in RA neutrophils which may explain the cause of their dysregulation in inflammatory disease.

Stimulatory Effect of Tofacitinib on Bone Marrow Adipocytes Differentiation.

BackgroundSystemic inflammation is the main factor underlying secondary osteoporosis in patients with rheumatoid arthritis (RA). Janus kinase inhibitors (JAKi), such as tofacitinib (Tofa), can control systemic inflammation and may have beneficial effects on bone in various models. This might be due to direct effects on the bone microenvironment and not exclusively based on their anti-inflammatory function. Bone marrow adipocytes (BMAds) are abundant in the bone microenvironment. The effect of JAKi on BMAds is unknown, but evidence suggests that there is competition between human bone marrow-derived stromal cell (hBMSC) differentiation routes towards BMAds and osteoblasts (Ob) in osteoporosis.ObjectivesThe aims of the study are to determine whether Tofa influences BMAds and Ob derived from hBMSCs and to investigate the potential effects of Tofa on bone marrow adiposity in RA patients.MethodsTo determine the effect of Tofa on cellular commitment, hBMSCs were differentiated to BMAds or OBs for 3 days together with Tofa at 200, 400, or 800 nM and TNFα. This study was also conducted using differentiated BMAds. The impact of Tofa was determined by gene and protein expression analysis and cell density monitoring. In parallel, in a pilot study of 9 RA patients treated with Tofa 5 mg twice a day (NCT04175886), the proton density fat fraction (PDFF) was measured using MRI at the lumbar spine at baseline and at 6 months.ResultsIn non-inflammatory conditions, the gene expression of Runx2 and Dlx5 decreased in Ob treated with Tofa (p <0.05). The gene expression of PPARγ2, C/EBPα, and Perilipin 1 were increased compared to controls (p <0.05) in BMAds treated with Tofa. Under inflammatory conditions, Tofa did not change the expression profiles of Ob compared to TNFα controls. In contrast, Tofa limited the negative effect of TNFα on BMAd differentiation (p <0.05). An increase in the density of differentiated BMAds treated with Tofa under TNFα was noted (p <0.001). These findings were consolidated by an increase in PDFF at 6 months of treatment with Tofa in RA patients (46.3 ± 7.0% versus 53.2 ± 9.2% p <0.01).ConclusionTogether, these results suggest a stimulatory effect of Tofa on BMAd commitment and differentiation, which does not support a positive effect of Tofa on bone.

Effect of Janus kinase inhibitors on T cell responses to herpes zoster in rheumatoid arthritis patients.

The incidence of herpes zoster (HZ) in rheumatoid arthritis (RA) patients is greater than that in healthy controls (HC), particularly in RA patients treated with Janus kinase inhibitors (JAKi). Here, we examined the effect of JAKi on CD4+/CD8+ T cells, cytokine production, and regulation of transcriptional factors in RA patients and HC. Peripheral blood mononuclear cells (PBMCs) obtained from RA patients (n=14) and HCs (n=7) were stimulated with varicella zoster virus lysates and exposed to three JAKi inhibitors (ruxolitinib [JAK1/2 inhibitor]; AG490 [JAK2 inhibitor]; and WHI-P154 [JAK3 inhibitor]) in the presence/absence of methotrexate. The CD4+ and CD8+ T cell populations were measured by flow cytometry. Cytokine levels in culture medium were measured by ELISA. Transcription factor expression was examined by RT-qPCR. There was a reduction in the CD4+IFN-γ+, CD4+CD69+IFN-γ+, CD8+IFN-γ+, and CD8+CD69+IFN-γ+ populations, and an increase in the CD4+CD25highFoxp3+ cell population, in PBMCs from RA patients and HCs after exposure to the three JAKi. ELISA revealed a reduction in IFN-γ and granzyme B levels in the presence of JAKi. JAKi reduced expression of mRNA encoding STAT1 and T-bet, but increased that of mRNA encoding STAT5 and Foxp3. Methotrexate plus the highest dose of each JAKi did not affect the Th1, cytotoxic T cell, or Treg populations, the levels of IFN-γ and granzyme B, or expression of transcription factors, significantly. JAKi reduce the Th1/cytotoxic T cell population and increase the Treg population in both RA patients and HC patients.

Effect of JAK inhibitors on high- and low-density lipoprotein in patients with rheumatoid arthritis: a systematic review and network meta-analysis.

Janus kinase (JAK) inhibitors are a new class of medication for treatment of rheumatoid arthritis (RA), and such inhibitors alter levels of high-density lipoprotein (HDL) and low-density lipoprotein (LDL) in RA patients. However, the extent of such changes has not been systematically reviewed. A systematic review and network meta-analysis was performed on randomized trials in RA patients in response to JAKi identified from Pubmed, Medline, Embase, and Cochrane Controlled Trials Register. The primary outcome was mean change of HDL-C and LDL-C from baseline. Mean treatment differences and the rank of the effect of various JAKi on HDL-C and LDL-C were estimated. Based on data from 18 unique studies involving five approved JAK inhibitors and 6697 RA patients (JAKi = 3341, placebo = 3356), such inhibitors led to a mean increase of 8.11mg/dl (95% CI 6.65-9.58, I2 = 82%) in HDL levels from baseline, and a mean increase of 11.37mg/dl (95% CI 7.84-14.91, I2 = 88%) in LDL levels from baseline. Cardiovascular disease risk did not differ significantly between patients who received JAK inhibitors or those who received placebo or active agents. Our analysis suggests that, at their recommended doses, all five JAK inhibitors lead to an increase in HDL and LDL levels in RA patients. Further long-term research is required to extend these results and understand whether changes in lipid levels in RA patients can affect cardiovascular risk. Key Points • This is the first systematic review and NMA examining the effect of all five clinically approved JAK inhibitors on lipid levels in RA patients. • Recommended doses of JAK inhibitors used for the treatment of RA patients can induce a significant increase in HDL and LDL levels. • Indirect pairwise comparisons suggest that only upadacitinib and peficitinib have significantly different ability to induce LDL change in RA patients.

Nocebo effects of Janus kinase inhibitors in the treatment of active ankylosing spondylitis.

Nocebo effects of Janus kinase inhibitors in the treatment of active ankylosing spondylitis.

Biologic therapies for the treatment of ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disease predominantly affecting the axial skeleton. AS treatment aims to reduce pain and inflammation and maintain functional capacity. Nonsteroidal anti-inflammatory drugs are the first-line treatment for those with active AS. While for peripheral arthritis, sulfasalazine or local glucocorticoid injection can be used, these are not recommended for axial symptoms. Twenty years ago, biological products that target the tumor necrosis factor (TNF) were developed. These have been approved for use in rheumatoid arthritis and AS. Since the introduction of these TNF inhibitors, the control of disease activity in AS has improved markedly. TNF inhibitors, including both anti-TNF-alpha monoclonal antibodies and recombinant TNF soluble receptors, can be considered for patients with persistently active disease despite nonsteroidal anti-inflammatory drug treatment. Recently, interleukin-17 inhibitors have also been approved for use in AS patients with insufficient responses to TNF inhibitors. Ongoing clinical trials are exploring the effect of Janus kinase inhibitors against AS. This review summarizes the current pharmaceutical treatment for AS, focusing on the biological products. Recommendations for AS management are also discussed in this review.

JAK Inhibitors and Modulation of B Cell Immune Responses in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic, systemic immune-mediated inflammatory disease that can lead to joint destruction, functional disability and substantial comorbidity due to the involvement of multiple organs and systems. B cells have several important roles in RA pathogenesis, namely through autoantibody production, antigen presentation, T cell activation, cytokine release and ectopic lymphoid neogenesis. The success of B cell depletion therapy with rituximab, a monoclonal antibody directed against CD20 expressed by B cells, has further supported B cell intervention in RA development. Despite the efficacy of synthetic and biologic disease modifying anti-rheumatic drugs (DMARDs) in the treatment of RA, few patients reach sustained remission and refractory disease is a concern that needs critical evaluation and close monitoring. Janus kinase (JAK) inhibitors or JAKi are a new class of oral medications recently approved for the treatment of RA. JAK inhibitors suppress the activity of one or more of the JAK family of tyrosine kinases, thus interfering with the JAK-Signal Transducer and Activator of Transcription (STAT) signaling pathway. To date, there are five JAK inhibitors (tofacitinib, baricitinib, upadacitinib, peficitinib and filgotinib) approved in the USA, Europe and/ or Japan for RA treatment. Evidence from the literature indicates that JAK inhibitors interfere with B cell functions. In this review, the main results obtained in clinical trials, pharmacokinetic, in vitro and in vivo studies concerning the effects of JAK inhibitors on B cell immune responses in RA are summarized.

Влияние селективных блокаторов янус-киназ и фосфодиэстеразы 4-го типа на концентрацию цитокинов в коже и крови больных псориазом

Влияние селективных блокаторов янус-киназ и фосфодиэстеразы 4-го типа на концентрацию цитокинов в коже и крови больных псориазом

Update on the Safety Profile of Tofacitinib in Rheumatoid Arthritis from Clinical Trials to Real-World Studies: A Narrative Review.

Tofacitinib is approved for the treatment of moderate to severe active rheumatoid arthritis (RA) in adult patients who do not respond adequately or are intolerant to one or more disease-modifying anti-rheumatic drugs. The tofacitinib RA clinical development program included randomized controlled trials of 6–24-month duration and long-term extension studies with > 7061 patients and 22,875 patient-years of exposure. To date, there are no data from other randomized studies in patients with cardiovascular risk factors comparing the long-term safety of a JAK inhibitor versus an anti-TNF. Real-world studies are necessary to complete the body of evidence supporting the effectiveness and safety of a therapeutic agent. In the case of tofacitinib, real-world data derive from health insurance claims databases, registries (US Corrona Registry, Swiss Registry, and others), national pharmacovigilance programs, and hospital databases (case series). The present article provides complete and up-to-date information on the safety profile of tofacitinib in RA, from clinical trials to real-world studies. Tofacitinib has demonstrated a consistent safety profile during up to 9.5 years of experience in randomized controlled trials and long-term extension studies. Real-world evidence has not added new safety issues with respect to those found in the clinical program. In general, the safety profile of tofacitinib is consistent with that of biologic disease-modifying anti-rheumatic drugs, with an increased risk of herpes zoster that seems to be a class effect of Janus kinase inhibitors. The continuous follow-up of therapeutic agents to treat rheumatoid arthritis is needed to adequately establish the safety profile for new mechanisms of action and potential risks associated with their longer term use.

Novel Concepts of Treatment for Patients with Myelofibrosis and Related Neoplasms.

Simple SummaryMyelofibrosis (MF) is an advanced form of a group of rare, related bone marrow cancers termed myeloproliferative neoplasms (MPNs). Some patients develop myelofibrosis from the outset, while in others, it occurs as a complication of the more indolent MPNs, polycythemia vera (PV) or essential thrombocythemia (ET). Patients with PV or ET who require drug treatment are typically treated with the chemotherapy drug hydroxyurea, while in MF, the targeted therapies termed Janus kinase (JAK) inhibitors form the mainstay of treatment. However, these and other drugs (e.g., interferons) have important limitations. No drug has been shown to reliably prevent the progression of PV or ET to MF or transformation of MPNs to acute myeloid leukemia. In PV, it is not conclusively known if JAK inhibitors reduce the risk of blood clots, and in MF, these drugs do not improve low blood counts. New approaches to treating MF and related MPNs are, therefore, necessary.Janus kinase (JAK) inhibition forms the cornerstone of the treatment of myelofibrosis (MF), and the JAK inhibitor ruxolitinib is often used as a second-line agent in patients with polycythemia vera (PV) who fail hydroxyurea (HU). In addition, ruxolitinib continues to be studied in patients with essential thrombocythemia (ET). The benefits of JAK inhibition in terms of splenomegaly and symptoms in patients with MF are undeniable, and ruxolitinib prolongs the survival of persons with higher risk MF. Despite this, however, “disease-modifying” effects of JAK inhibitors in MF, i.e., bone marrow fibrosis and mutant allele burden reduction, are limited. Similarly, in HU-resistant/intolerant PV, while ruxolitinib provides excellent control of the hematocrit, symptoms and splenomegaly, reduction in the rate of thromboembolic events has not been convincingly demonstrated. Furthermore, JAK inhibitors do not prevent disease evolution to MF or acute myeloid leukemia (AML). Frontline cytoreductive therapy for PV generally comprises HU and interferons, which have their own limitations. Numerous novel agents, representing diverse mechanisms of action, are in development for the treatment of these three classic myeloproliferative neoplasms (MPNs). JAK inhibitor-based combinations, all of which are currently under study for MF, have been covered elsewhere in this issue. In this article, we focus on agents that have been studied as monotherapy in patients with MF, generally after JAK inhibitor resistance/intolerance, as well as several novel compounds in development for PV/ET.

The effectiveness of Janus kinase inhibitors in treating atopic dermatitis: A systematic review and meta-analysis.

Primary studies have presented conflicting results on the efficacy of Janus kinase (JAK) inhibitors in treating atopic dermatitis. Hence, it is important to determine the summary effect of JAK inhibitors in order to guide the clinical application of this potentially beneficial drug. To determine the efficacy of JAK inhibitors in treating atopic dermatitis in all age groups. A systematic review with meta-analyses of randomized controlled trials (RCTs) reporting on the effect of JAK inhibitors on the signs and symptoms of atopic dermatitis were conducted. Six electronic databases, registries, and search engines (PubMed, Cochrane Central Register of Controlled Trials [CENTRAL], Google Scholar, ScienceDirect, Clinical.gov, and WHO ICTRP) were searched from inception to September, 2019. The search terms include "atopic dermatitis," "eczema," and "Janus kinase inhibitor." The search was restricted to humans. A total of 413 studies were identified through the database search and hand-searching. After the selection process, five RCTs were included in this systematic review. A meta-analysis of three studies showed that JAK inhibitors were effective in reducing Eczema Area and Severity Index (P = .0001) and pruritus scores (P = .0001). JAK inhibitors appear to be effective in treating atopic dermatitis. Future studies should aim to evaluate its cost-effectiveness and availability to patients especially in developing countries.