Ruxolitinib treatment ameliorates clinical, immunologic, and transcriptomic aberrations in patients with STAT3 gain-of-function disease

BACKGROUND

Signal transducer and activator of transcription 3 (STAT3) gain-of-function (GOF) disease presents with lymphoproliferation, autoimmunity, and failure to thrive. Although Janus kinase inhibitors have alleviated symptoms, their effects on disease pathogenesis remain unclear.

OBJECTIVE

We prospectively investigated the clinical, immunologic, and transcriptomic responses of 4 patients with STAT3 GOF under long-term ruxolitinib treatment.

METHODS

We conducted clinical and immunologic evaluations at baseline and after ruxolitinib treatment at 3, 8, 12, and more than 12 months. Our assessments included measurement of levels of circulating T follicular helper cells, regulatory T cells, and cytokines, as well as proliferation assays. Furthermore, we investigated the transcriptomic changes with treatment and conducted T-cell receptor sequencing.

RESULTS

Ruxolitinib achieved substantial control over the clinical manifestations. Posttreatment evaluations demonstrated a notable increase in naive CD4+ and CD8+ T-cell populations, alongside a significant reduction in effector memory T-cell levels. Additionally, there was a decrease in levels of circulating T follicular helper cells and double-negative T cells. Regulatory T-cell percentages and their canonical markers, which were already reduced before treatment, declined further with ruxolitinib. The treatment did not alter the production of IL-4, IL-17A, IL-10, and IFN-γ cytokines by the CD4+ T cells. Importantly, ruxolitinib effectively normalized the previously dysregulated transcriptome profile in PBMCs, bringing it closer to that of healthy controls. This normalization was most striking in the downregulation of STAT3-targeted genes, interferon-related genes, myeloid cell activation, and cytotoxic effector CD8+ T-cell genes, with effects persisting for up to 12 months. Self-reactive T-cell indices based on T-cell receptor repertoire analysis revealed potential autoreactive cell clones in the patient samples.

CONCLUSION

Ruxolitinib reversed cellular and transcriptomic signatures, enhancing our understanding of the disease's pathophysiology and highlighting essential immunologic markers for precise monitoring.

Development and validation of an LC-MS/MS method for ruxolitinib quantification: advancing personalized therapy in hematologic malignancies

Background

Hematologic malignancies such as leukemia and lymphoma present treatment challenges due to their genetic and molecular heterogeneity. Ruxolitinib, a Janus kinase (JAK) inhibitor, has demonstrated efficacy in managing these cancers. However, optimal therapeutic outcomes are contingent upon maintaining drug levels within a therapeutic window, highlighting the necessity for precise drug monitoring.

Methods

We developed a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify ruxolitinib in human plasma, improving upon traditional methods in specificity, sensitivity, and efficiency. The process involved the use of advanced chromatographic techniques and robust mass spectrometric conditions to ensure high accuracy and minimal matrix effects. The study was conducted using samples from 20 patients undergoing treatment, with calibration standards ranging from 10 to 2000 ng/mL.

Results

The method displayed linearity (R 2 > 0.99) across the studied range and proved highly selective with no significant interference observed. The method's precision and accuracy met FDA guidelines, with recovery rates consistently exceeding 85%. Clinical application demonstrated significant variability in ruxolitinib plasma levels among patients, reinforcing the need for individualized dosing schedules.

Conclusion

The validated LC-MS/MS method offers a reliable and efficient tool for the therapeutic drug monitoring of ruxolitinib, facilitating personalized treatment approaches in hematologic malignancies. This approach promises to enhance patient outcomes by optimizing dosing to reduce toxicity and improve efficacy.

Ruxolitinib in patients with polycythemia vera resistant and/or intolerant to hydroxyurea: European observational study

BACKGROUND

Hydroxyurea (HU) is a commonly used first-line treatment in patients with polycythemia vera (PV). However, approximately 15%-24% of PV patients report intolerance and resistance to HU.

METHODS

This phase IV, European, real-world, observational study assessed the efficacy and safety of ruxolitinib in PV patients who were resistant and/or intolerant to HU, with a 24-month follow-up. The primary objective was to describe the profile and disease burden of PV patients.

RESULTS

In the 350 enrolled patients, 70% were >60 years old. Most patients (59.4%) had received ≥1 phlebotomy in the 12 months prior to the first dose of ruxolitinib. Overall, 68.2% of patients achieved hematocrit control with 92.3% patients having hematocrit <45% and 35.4% achieved hematologic remission at month 24. 85.1% of patients had no phlebotomies during the study. Treatment-related adverse events were reported in 54.3% of patients and the most common event was anemia (22.6%). Of the 10 reported deaths, two were suspected to be study drug-related.

CONCLUSION

This study demonstrates that ruxolitinib treatment in PV maintains durable hematocrit control with a decrease in the number of phlebotomies in the majority of patients and was generally well tolerated.

Efficacy and safety of combination therapies vs monotherapy of hypomethylating agents in accelerated or blast phase of Philadelphia negative myeloproliferative neoplasms: a systematic review and meta-analysis

BACKGROUND

There is a lack of evidence regarding whether combination therapy of hypomethylating agents (HMAs) has better outcomes than HMA monotherapy in patients with Philadelphia chromosome-negative accelerated or blast phase myeloproliferative neoplasms (MPN-AP/BP).

MATERIALS AND METHODS

Pubmed, Embase, Web of Science and Cochrane library databases were searched for studies from inception of each database until 31 December 2021. Data extraction and synthesis were conducted following the PRISMA reporting guideline.

RESULTS

It was found that HMAs plus venetoclax therapy yielded a higher CR/CRi rate than HMAs alone [36% vs 19%, p = .0204] and a higher CR rate than HMAs plus ruxolitinib [22% vs 8%, p = .0313]. HMAs plus ruxolitinib combination showed a higher ORR than HMA monotherapy [45% vs 30%, p = .0395], but there was no improvement in CR/CRi. The one-year and two-year OS rate for patients treated with HMAs plus venetoclx/ruxolitinib demonstrated a trend towards prolonged survival than HMAs alone [HMAs plus venetoclax: 24% vs 11%, p = .1295 and 12% vs 3%, p = .2357; HMAs plus ruxolitinib: 25% vs 11%, p = .0774 and 33% vs 3%, p = .051].

CONCLUSION

It was confirmed that HMA in combination with venetoclax is an effective and well-tolerated option in MPN-AP/BP patients in pre- as well as post-haematopoietic stem cell transplantation settings. HMA plus ruxolitinib therapy was revealed to be effective in patients with MPN-AP.Key MessagesCombination therapy with HMAs and venetoclax/ruxolitinib was associated with improved outcomes than HMAs alone in MPN-AP/BP patients.Further large-scale randomized controlled trials are needed to confirm regarding to the optimal treatment for this patient population.

Addition of ruxolitinib in Graft-versus-Host disease prophylaxis for pediatric β-Thalassemia major patients after allogeneic stem cell transplantation: A retrospective cohort study

BACKGROUND

To evaluate the effect of addition of ruxolitinib in Graft-versus-Host Disease (GVHD) prophylaxis on pediatric patients with β-thalassemia major after allogeneic hematopoietic stem cell transplantation(HSCT).

METHODS

This retrospective study reviewed 49 consecutive β-thalassemia major pediatric patients who underwent HSCT from unrelated or haploidentical donors from February 2018 to October 2022. All transplantation recipients received cyclosporine A (CsA), mycophenolate mofetil (MMF), and short-term methotrexate (MTX) as GVHD prophylaxis; while 27 of them in the ruxolitinib group had added ruxolitinib oral to GVHD prophylaxis regimen at 2.5 mg twice daily once successful engraftment after January 2020.

RESULTS

The outcome showed that the ruxolitinib group had a lower cumulative incidence than the control group regardless of acute GVHD (22.2% vs.40.9%; p = .153) or chronic GVHD (18.5% vs.40.9%; p = .072); especially, the incidence of grade III-IV acute GVHD was reported significantly less frequently in ruxolitinib group than that of the control group (0 vs. 27.3%, p = .005). No significant difference was detected between the two groups in EBV (Epstein-Barr virus)/CMV (cytomegalovirus) reactivation and BKV (BK virus) infection (p = .703, 1.000, and .436, respectively). Twenty-six patients (96.3%) in the ruxolitinib group were alive, while two patients (9.1%) in the control group died of intestinal acute GVHD. The 2-year overall survival (OS) and thalassemia-free survival (TFS) were both 96.296% in the ruxolitinib group, while both 90.909% in the control group.

CONCLUSION

This study reveals that ruxolitinib prophylaxis is a promising option to decrease the incidence of grade III-IV acute GVHD in pediatric patients with β-thalassemia major.

Combination of azacitidine, venetoclax and ruxolitinib in blast phase myeloproliferative neoplasms

Myeloproliferative neoplasms in blastic phase (MPN-BP) have a dreadful prognosis. We report the characteristics and outcomes of five MPN-BP patients treated with a never-before-described combination of azacytidine and venetoclax (to control BP transformation), added to ruxolitinib (needed to control constitutional symptoms). Median age was 76 years (range 72-84), and worst performance status was 2. The overall response rate was 80%, and the complete remission rate was 40%. With median follow-up of 10.0 months (range 4.2-13.4), median overall survival was 13.4 months (95% CI 4.2-13.4). We did not detect any unexpected treatment-related toxicity, and quality of life was improved.

Review of Ruxolitinib for Treatment of Non-Segmental Vitiligo

OBJECTIVE

To review the pharmacokinetics, efficacy, and safety of topical ruxolitinib for treatment of nonsegmental vitiligo.

DATA SOURCES

Literature published between January 1983 and October 2022 was reviewed from MEDLINE and ClinicalTrials.gov.

STUDY SELECTION AND DATA EXTRACTION

Relevant articles in English and data from clinical trials were included.

DATA SYNTHESIS

In 2 phase II trials, treatment with ruxolitinib cream showed significant improvements in Vitiligo Area Scoring Index (VASI) scores compared with controls. The 1.5% concentration applied twice daily showed the best results after 52 weeks, with 50% VASI improvement in 58% of patients, 75% VASI improvement in 52% of patients, and 90% VASI improvement in 33% of patients. In 2 phase III trials, more patients achieved at least 75% improvement in facial VASI at 24 weeks (primary endpoint; trial 1: 29.9%, trial 2: 29.9%) than controls (trial 1: 7.5% [P < 0.0001], trial 2: 12.9% [P < 0.01]). Common adverse effects were erythema, pruritus, and acne; all events were mild.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING DRUGS

This review summarizes the pharmacokinetics, efficacy, and safety data regarding topical ruxolitinib for vitiligo. Ruxolitinib is associated with significant clinical improvements with low bioavailability and minimal adverse effects compared with conventional topical steroids, calcineurin inhibitors, phototherapy, and depigmentation agents.

CONCLUSIONS

Ruxolitinib cream is the first therapy approved by the Food and Drug Administration for repigmentation of nonsegmental vitiligo. Clinicians should consider these benefits when recommending treatment as conventional therapies may be time-intensive and carry greater risks of adverse effects.

Sensitive Quantitative In Vivo Assay for Evaluating the Effects of Biomolecules on Hair Growth and Coloring Using Direct Microinjections into Mouse Whisker Follicles

Many people suffer from hair loss and abnormal skin pigmentation, highlighting the need for simple assays to support drug discovery research. Current assays have various limitations, such as being in vitro only, not sensitive enough, or unquantifiable. We took advantage of the bilateral symmetry and large size of mouse whisker follicles to develop a novel in vivo assay called "whisker follicle microinjection assay". In this assay, we plucked mouse whiskers and then injected molecules directly into one side of the whisker follicles using microneedles that were a similar size to the whiskers, and we injected solvent on the other side as a control. Once the whiskers grew out again, we quantitatively measured their length and color intensity to evaluate the effects of the molecules on hair growth and coloring. Several chemicals and proteins were used to test this assay. The chemicals minoxidil and ruxolitinib, as well as the protein RSPO1, promoted hair growth. The effect of the clinical drug minoxidil could be detected at a concentration as low as 0.001%. The chemical deoxyarbutin inhibited melanin production. The protein Nbl1 was identified as a novel hair-growth inhibitor. In conclusion, we successfully established a sensitive and quantitative in vivo assay to evaluate the effects of chemicals and proteins on hair growth and coloring and identified a novel regulator by using this assay. This whisker follicle microinjection assay will be useful when investigating protein functions and when developing drugs to treat hair loss and abnormal skin pigmentation.

Head and Neck Reconstruction in Patients with Polycythemia Vera: Case Series and Literature Review

Background  Polycythemia vera (PV) is a myeloproliferative disease with overproduction of erythrocytes, leukocytes, and platelets causing an increased risk of both thrombosis and hemorrhage. There are limited reports and no established guidelines for managing such patients undergoing reconstructive surgery. Methods  We present four patients with PV and head and neck cancer who required reconstruction after resection and provide a review of the current literature. Results  Preoperatively, patients on cytoreductive therapy continued with their treatment throughout their hospital course and had hematologic parameters normalized with phlebotomy or transfusions if needed. Two patients who underwent free flap surgery (cases 1 and 2) had postoperative courses complicated by hematoma formation and persistent anemia, requiring multiple transfusions. Cases 3 and 4 (JAK2+ PV and JAK2- PV, respectively) underwent locoregional flap without postoperative complications. Conclusion  Concomitant presentation of PV and head and neck cancer is uncommon and presents unique challenges for the reconstructive surgeon. Overall, we recommend that patients should have hematologic parameters optimized prior to surgery, continue ruxolitinib or hydroxyurea, and hold antiplatelet/anticoagulation per established department protocols. It is essential to engage a multidisciplinary team involving hematology, head and neck and reconstructive surgery, anesthesia, and critical care to develop a standardized approach for managing this unique subset of patients.

Breaking the storm: ruxolitinib as a lifeline in refractory hemophagocytic lymphohistiocytosis with macrophage activation syndrome

This case report presents the management of a 25-year-old woman with refractory hemophagocytic lymphohistiocytosis (HLH) secondary to adult-onset Still's disease. Despite initial treatment with corticosteroids and biologic therapies, including anakinra and tocilizumab, her condition continued to deteriorate, necessitating intensive care unit admission. Following multidisciplinary consultation, ruxolitinib therapy, a Janus kinase (JAK) inhibitor targeting hyperinflammation, was initiated. Remarkably, the patient exhibited significant clinical improvement with resolution of fever, normalization of inflammatory markers, and organ function recovery. This case underscores the potential of ruxolitinib as a therapeutic option in refractory cases of HLH or macrophage activation syndrome, highlighting the importance of exploring novel therapies in refractory and challenging clinical scenarios.

Treatment Strategies Used in Treating Myelofibrosis: State of the Art

BACKGROUND

Current drug therapy for myelofibrosis does not alter the natural course of the disease or prolong survival, and allogeneic stem cell transplantation is the only curative treatment modality. For over a decade, the Janus kinase (JAK) inhibitor ruxolitinib has been the standard of care. More recently, newer-generation JAK inhibitors have joined the ranks of accepted treatment options.

OBJECTIVES

The primary goal of treatment is to reduce spleen size and minimize disease-related symptoms. Prognostic scoring systems are used to designate patients as being at lower or higher risk. For transplant-eligible patients, transplant is offered to those with a bridge of a JAK inhibitor; patients who are not eligible for transplant are usually offered long-term therapy with a JAK inhibitor. Limited disease-modifying activity, dose-limiting cytopenias, and other adverse effects have contributed to discontinuation of JAK inhibitor treatment.

CONCLUSIONS

Novel JAK inhibitors and combination approaches are currently being explored to overcome these shortcomings. Further research will be essential to establish optimal therapeutic approaches in first-line and subsequent treatments.

Novel strategies for challenging scenarios encountered in managing myelofibrosis

Given its rarity, multi-faceted clinical presentation and the relative paucity of approved therapies, the management of myeloproliferative neoplasm (MPN)-associated myelofibrosis (MF) can be challenging. Janus kinase (JAK) inhibitors, the only approved agents at present, have brought many clinical benefits to patients, with prolongation of survival also demonstrated for ruxolitinib. However, these agents have clear limitations. Optimal management of anemia in MF remains a major unmet need. Neither ruxolitinib nor fedratinib is recommended for use in patients with severe thrombocytopenia, i.e. platelets <50 × 109/L, who have a particularly poor prognosis. The search for the optimal partner for JAK inhibitors to address some of the shortcomings of these agents (e.g. limited ability to improve bone marrow fibrosis, cytopenias and induce molecular responses) and achieve meaningful 'disease modification' continues. This has led to the development of a number of rational, preclinically synergistic combinations for use either upfront or in the setting of sub-optimal response to JAK inhibition. Finally, the outlook for patients whose disease progresses on JAK inhibitor therapy continues to be grim, and agents with alternative mechanisms of action may be needed in this setting. In this article, we use a case-based approach to illustrate challenges commonly encountered in clinical practice and our management of the same. Fortunately, there has been enormous growth in drug development efforts in the MF space in the last few years, some of which appear poised to bear fruit in the very near future.

Vitiligo Exchange: An Expert Panel Discussion of Two Clinical Cases

This article is based on a roundtable discussion in which three panelists review clinically relevant insights about vitiligo and discuss two cases that illustrate the multiple challenges faced by both patients and clinicians in managing this complex disease. The first is a 32-year-old White female patient with Fitzpatrick Skin Type III/IV with extensive depigmentation in the trunk area. The patient achieved 90-percent repigmentation with a combination therapy approach. Treatment included systemic corticosteroids, oral antioxidants, narrowband ultraviolet B phototherapy, and topical therapy initially with tacrolimus ointment followed by topical ruxolitinib cream. Patient counseling around variable rates of progressive repigmentation over time, the significance of combining therapeutic approaches, and the importance of treatment consistency are discussed. The second case is that of a White pediatric female patient with vitiligo, who was treated from the ages of 5 to 11 years, with a break in treatment due to the patient's desire to discontinue treatment. Once treatment recommenced, the patient ultimately achieved 75-percent repigmentation within six months using a combination of narrowband ultraviolet B phototherapy, topical corticosteroids, and topical calcineurin inhibitors. The emotional burden of pediatric vitiligo for patients and their caregivers are discussed, along with joint decision making with this patient and her parents. This was followed by a discussion of the significance of the patient's anti-nuclear antibody positivity and how this affects treatment approach in patients with vitiligo.

Real-world treatment patterns and health outcomes for patients with myelofibrosis treated with fedratinib

AIM

Assess real-world fedratinib (FEDR) treatment patterns and clinical outcomes in patients with primary or secondary myelofibrosis following discontinuation of ruxolitinib (RUX).

PATIENTS & METHODS

This study was a retrospective, noninterventional medical record review of patients in Canada, Germany, and the United Kingdom (UK). A total of 70 physicians (primarily hematologist-oncologists [78.6%]) provided data for 196 eligible patients.

RESULTS

Patients were mostly male (62.8%) with primary myelofibrosis (76.5%) and initiated FEDR at a mean age of 67.7 years. Median treatment duration was 11.5 months (median follow-up, 13.8 months), and nearly half (49.5%) of patients initiated FEDR at the label-indicated dose of 400 mg daily. Six months post-initiation, 77.7% and 66.8% of patients experienced symptom and spleen response, respectively. Kaplan-Meier estimates of median progression-free and overall survival from initiation were 23.8 months (95% CI, 21.1-27.6) and 29.8 months (95% CI, 23.9-NE), respectively.

CONCLUSION

These findings demonstrate real-world FEDR effectiveness among patients with myelofibrosis who discontinued RUX.

5-azacitidine reversing "spent" phase polycythemia vera back to proliferative phase and need for phlebotomy

INTRODUCTION

Polycythemia vera is a myeloproliferative neoplasm (MPN) characterized by increased red blood cell mass. The natural evolution of this MPN is to progress to an anemic/cytopenic phase also known as "spent" phase prior to transformation into an accelerated and/or an overt leukemic phase.

CASE REPORT

Herein, we describe a case of a patient with polycythemia vera transitioning though a "spent" phase to an MPN in accelerated phase (MPN-AP). The patient had anemia, thrombocytopenia, neutrophilia and increased blasts in the bone marrow. Management and outcome: Upon treatment with four cycles of 5-azacitidine, the patient's polycythemia vera reversed back to the proliferative phase. Serial phlebotomies were again required.

DISCUSSION

Reversal of a "spent" phase by 5-azacitidine back to a proliferative polycythemia vera phase requiring phlebotomies has not been previously reported in the scientific literature. We might witness similar cases in the literature in the future years, which could lead to yet another therapeutic indication of this important pharmacologic agent.

Case Report: Avelumab and ruxolitinib to manage polycythemia vera and secondary metastatic Merkel cell carcinoma: a possible successful combination

We describe a case of second primary malignancy in a 65-year-old patient affected by polycythemia vera treated with the JAK 1/2 inhibitor ruxolitinib. The latter is recognized as a risk factor for the onset of non-melanoma skin cancers in many retrospective and perspective studies, but the concomitant use of ruxolitinib with new immunotherapies is very rarely reported, and the safety of this association is still not clear. In our case, ruxolitinib combined with the anti-PD-L1 avelumab demonstrated both safety and efficacy for hematological disease control and underlying carcinoma remission.

Successful ruxolitinib administration for a patient with steroid-refractory idiopathic pneumonia syndrome following hematopoietic stem cell transplantation: A case report and literature review

Idiopathic pneumonia syndrome (IPS) is an acute lung complication observed after the early posthematopoietic stem cell transplantation (HSCT) period. Ruxolitinib was effective for a patient with myelodysplastic syndrome who developed severe IPS after second HSCT. No severe adverse effects were observed. Ruxolitinib may be an alternative choice for HSCT-related IPS.

Rapid Hepatomegaly From Ruxolitinib Discontinuation Syndrome

Introduction

Ruxolitinib (RUX) is a Food and Drug Administration-approved Janus Kinase (JAK) inhibitor shown to be effective in improving hypercatabolic symptoms and splenomegaly in patients with myelofibrosis (MF). RUX therapy provides symptomatic benefits for MF patients but is often discontinued for various reasons including worsening cytopenias. Ruxolitinib Discontinuation Syndrome (RDS) involves an acute cytokine-storm rebound phenomenon that can manifest as an acute relapse of symptoms, worsening splenomegaly, respiratory distress, systemic inflammatory response syndrome, or disseminated intravascular coagulopathy.

Case Presentation

We present the case of a patient with JAK2-positive post-polycythemia vera MF, whose RUX therapy was discontinued due to an active gastrointestinal (GI) bleed and worsening cytopenias. The patient had recently started azacitidine and was on the drug combination prior to hospitalization. The patient developed what appears to be the first case of acute onset accelerated massive hepatomegaly, a previously undescribed clinical manifestation of RDS.

Conclusion

Although rare, medical professionals should maintain a high suspicion of RDS in hospitalized patients following the discontinuation of RUX.

Predictors of Response to Hydroxyurea and Switch to Ruxolitinib in HU-Resistant Polycythaemia VERA Patients: A Real-World PV-NET Study

In polycythemia vera (PV), the prognostic relevance of an ELN-defined complete response (CR) to hydroxyurea (HU), the predictors of response, and patients' triggers for switching to ruxolitinib are uncertain. In a real-world analysis, we evaluated the predictors of response, their impact on the clinical outcomes of CR to HU, and the correlations between partial or no response (PR/NR) and a patient switching to ruxolitinib. Among 563 PV patients receiving HU for ≥12 months, 166 (29.5%) achieved CR, 264 achieved PR, and 133 achieved NR. In a multivariate analysis, the absence of splenomegaly (p = 0.03), pruritus (p = 0.002), and a median HU dose of ≥1 g/day (p < 0.001) remained associated with CR. Adverse events were more frequent with a median HU dose of ≥1 g/day. Overall, 283 PR/NR patients (71.3%) continued HU, and 114 switched to ruxolitinib. In the 449 patients receiving only HU, rates of thrombosis, hemorrhages, progression, and overall survival were comparable among the CR, PR, and NR groups. Many PV patients received underdosed HU, leading to lower CR and toxicity rates. In addition, many patients continued HU despite a PR/NR; however, splenomegaly and other symptoms were the main drivers of an early switch. Better HU management, standardization of the criteria for and timing of responses to HU, and adequate intervention in poor responders should be advised.

Cord blood T regulatory cells synergize with ruxolitinib to improve GVHD outcomes

Background

Adoptive therapy with umbilical cord blood (UCB) T-regulatory (Treg) cells can prevent graft vs. host disease (GVHD). We hypothesize that UCB Tregs can treat GVHD and synergize with ruxolitinib, Jak2 inhibitor, to improve outcomes.

Methods

UCB Treg potency and efficacy was examined using cell suppression assay and xenogeneic GVHD model, respectively. Ruxolitinib was fed continuously in presence or absence of CellTraceViolet tagged UCB Tregs on days +4, +7, +11, +18. Mice were followed for survival, GVHD score, hematology parameters and inflammation.

Results

Addition of ruxolitinib to UCB Tregs exerted synergistic suppressor function in vitro and improved persistence of UCB Tregs in vivo. Lower GVHD score, improved survival, increased hemoglobin level and platelet count, decreased inflammatory cytokines and decrease in CD3+ T cell lung infiltrate was observed in UCB Tregs+ruxolitinib recipients.

Conclusion

UCB Treg+Ruxolitinib combination improves outcomes in xenogeneic GVHD and should be explored in a clinical setting.

JAK inhibitors in vitiligo: what they hit and what they miss - an immunopathogenesis based exposition of existing evidence

INTRODUCTION

Vitiligo is an autoimmune disorder which presents as depigmented macules due to selective loss of melanocytes. Heightened expression of Janus Kinase Signal transducers and activators of transcription (JAK STAT) pathway, which mediate cytokines action, suggest that targeting this signaling pathway may be an effective option.

AREAS COVERED

A PubMed search was carried out with the broad key words 'JAK,' 'vitiligo' from 2016 to 2023. We also analyzed papers where tissue-based JAK expression was studied, with or without concomitant treatment with JAK inhibitors. We address the role of JAK inhibitors in vitiligo and their effect on repigmentation of lesions.

EXPERT OPINION

While JAK inhibitors help in cessation of disease progression, they have no in vivo action on melanocyte proliferation and hence cannot result in re-pigmentation as a monotherapy. There is a need for tissue-based JAK and cytokine-based studies with post-treatment expression data to validate the role of this class of drugs in vitiligo. There is as yet no data to suggest that selective JAK inhibitors are superior to pan JAK inhibitors for vitiligo. JAK inhibitors are useful in active disease and effectively modulate the cytokine mediated autoimmune dammage and makes them singularly superior to oral glucocorticosteroids.