Safety and Efficacy of Infliximab Therapy in the Setting of Steroid-Refractory Acute Graft-versus-Host Disease

Fatal acute graft-versus-host disease in Sézary Syndrome treated with Mogamulizumab and hematopoietic cell transplantation

Sézary syndrome (SS) is a rare and aggressive T-cell lymphoma with a poor prognosis in advanced stages. Allogeneic hematopoietic cell transplantation (allo-HCT) offers a potential cure, but complications such as graft-versus-host disease (GvHD) remain a clinical challenge. Mogamulizumab, a humanized anti-CC chemokine receptor 4 (CCR4) antibody, is sometimes used as a bridge to transplantation, but its potential interactions with allo-HCT are unclear. This report describes the case of a 37-year-old man with advanced SS who received mogamulizumab therapy followed by allo-HCT from an HLA-identical sibling donor. The patient developed severe gastrointestinal acute GvHD, which was treated with steroids and infliximab. However, the condition rapidly progressed to severe intestinal symptoms and life-threatening haemorrhagic shock, ultimately resulting in the patient's death. This case highlights a potential link between mogamulizumab and severe acute GvHD promoted by drug-induced suppression of regulatory T cells. Further research is required to fully understand the interaction between mogamulizumab and allo-HCT and to determine whether it is an optimal approach as a bridge to transplant therapy. This paradigmatic case suggests the need of personalizing transplant strategies by selecting appropriate conditioning therapy and GvHD prophylaxis to minimize potential toxicity.

Vedolizumab plus basiliximab as second-line therapy for steroid-refractory lower gastrointestinal acute graft-versus-host disease

Background

Steroid-resistant (SR) lower gastrointestinal (LGI) tract graft-versus-host disease (GVHD) is the predominant cause of morbidity and mortality from GVHD after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The role of vedolizumab in the treatment of SR-LGI acute GVHD (aGVHD) remains uncertain. We aimed to assess the efficacy and safety of vedolizumab combined with basiliximab as second-line therapy for SR-LGI-aGVHD.

Methods

This study aimed to explore the efficacy of vedolizumab combined with basiliximab for SR-LGI-aGVHD. The primary endpoint was the overall response (OR) on day 28. Secondary and safety endpoints included durable OR at day 56, overall survival (OS), chronic GVHD (cGVHD), non-relapse mortality (NRM), failure-free survival (FFS), and adverse events.

Results

Twenty-eight patients with SR-LGI-aGVHD were included. The median time to start of combination therapy after SR-LGI-aGVHD diagnosis was 7 (range, 4-16) days. The overall response rate (ORR) at 28 days was 75.0% (95% CI: 54.8%-88.6%), and 18 achieved a complete response (CR) (64.3%, 95% CI: 44.1%-80.7%). The durable OR at day 56 was 64.3% (95% CI: 44.1%-80.7%). The 100-day, 6-month, and 12-month OS rates for the entire cohort of patients were 60.7% (95% CI: 45.1%-81.8%), 60.7% (95% CI: 45.1%-81.8%), and 47.6% (95% CI: 31.4%-72.1%), respectively. The median failure-free survival was 276 days; (95% CI: 50-not evaluable) 12-month NRM was 42.9% (95% CI: 24.1%-60.3%). The 1-year cumulative incidence of cGVHD was 35.7%. Within 180 days after study treatments, the most common grade 3 and 4 adverse events were infections. Nine (32.1%) patients developed cytomegalovirus (CMV) reactivation complicated with bacterial infections (25.0%, CMV infection; 7.1%, CMV viremia). Epstein-Barr virus (EBV) reactivation occurred in five patients (17.9%, 95% CI: 6.8%-37.6%). Only three patients (10.7%, 95% CI: 2.8%-29.4%) in our study developed pseudomembranous colitis.

Conclusions

Vedolizumab plus basiliximab demonstrated efficacy in severe SR-LGI-aGVHD and was well-tolerated. Vedolizumab plus basiliximab may be considered a potential treatment option for patients with LGI-aGVHD.

Advantage of First-Line Therapeutic Drug Monitoring-Driven Use of Infliximab for Treating Acute Intestinal and Liver GVHD in Children: A Prospective, Single-Center Study

The high serum concentrations of TNF-α characterize acute graft-versus-host disease (aGVHD), for which infliximab treatment may be beneficial. In 28 pediatric patients, four doses of 10 mg/kg infliximab every seven days were administered after steroid failure (Standard Group, n = 14) or as a first-line therapy (Early Group, n = 14). Population pharmacokinetic analyses and evaluation of serum cytokines were performed. After two months of treatment, complete response in gastrointestinal and liver aGVHD was achieved in 43% and 100% of patients in the Standard and Early groups, respectively. During follow-up, four patients in the Standard Group (but none in the Early Group) experienced an aGVHD recurrence. Viral infections occurred more frequently in the Standard Group after the fifth dose. Infliximab clearance did not differ between groups or according to treatment outcome for each organ involved in aGVHD, whereas serum levels of cytokines significantly differed. Therefore, present findings show that use of first-line, TDM-driven infliximab to treat aGVHD in children may result in better clinical outcomes and tolerability, with a different pattern of cytokines generated according to the moment of beginning of treatment.

[Diagnosis, prophylaxis and therapeutic management of acute GVH: Guidelines from the SFGM-TC]

Acute GVHD is a potentially severe complication of hematopoietic stem cell transplantation, responsible for morbidity and mortality that can affect the prognosis after transplantation. Within the framework of the 12th workshop of practice harmonization of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), diagnostic modalities of acute GVHD are updated. The conventional prevention (depending on donor, conditioning, and stem cell source) and treatment schemes (depending on affected organ and intensity) of aGVHD are clarified, and new therapeutic options are discussed.

A biomarker signature to predict complete response to itacitinib and corticosteroids in acute graft-versus-host disease

A broad proteomic analysis was conducted to identify and evaluate candidate biomarkers potentially predictive of response to treatment with an oral selective Janus kinase 1 (JAK1) inhibitor, itacitinib, in acute graft‐versus‐host disease (GVHD). Plasma samples from 25 participants (identification cohort; NCT02614612) were used to identify novel biomarkers that were tested in a validation cohort from a placebo‐controlled, randomised trial (n = 210; NCT03139604). The identification cohort received corticosteroids plus 200 or 300 mg itacitinib once daily. The validation cohort received corticosteroids plus 200 mg itacitinib once daily or placebo. A broad proteomic analysis was conducted using a proximity extension assay. Baseline and longitudinal comparisons were performed with unpaired t‐test and one‐way analysis of variance used to evaluate biomarker level changes. Seven candidate biomarkers were identified. Monocyte‐chemotactic protein (MCP)3, pro‐calcitonin/calcitonin (ProCALCA/CALCA), together with a previously identified prognostic acute GVHD biomarker, regenerating islet‐derived protein (REG)3A, stratified complete responders from non‐responders (participants with progressive disease) to itacitinib, but not placebo, potentially representing predictive biomarkers of itacitinib in acute GVHD. ProCALCA/CALCA, suppressor of tumorigenicity (ST)2, and tumour necrosis factor receptor (TNFR)1 were significantly reduced over time by itacitinib in responders, potentially representing response‐to‐treatment biomarkers. Novel biomarkers have the potential to identify patients with acute GVHD that may respond to itacitinib plus corticosteroid treatment (NCT02614612; NCT03139604).

Steroid sensitive acute GVHD, but not steroid dependent or steroid resistant, results in similar infection risk as no GVHD following allogeneic hematopoietic cell transplantation

Patients with acute GVHD (aGVHD) have an increased risk for infectious complications after allogeneic hematopoietic cell transplantation (HCT), but the risk according to response to therapy is not well studied. We performed a retrospective analysis of the infectious complications for 1 year following allogeneic HCT at the University of Minnesota for 1143 pediatric and adult patients with and without aGVHD. Patients with aGVHD were classified into treatment response groups based on response to corticosteroids as first-line therapy: steroid sensitive (SS, n=114), steroid resistant (SR, n=103) and steroid dependent (SD, n=168) aGVHD. We observed that the cumulative incidence and density of infections for patients with SS aGVHD parallels those having no GVHD. Infection density (the number of infections that occurred per 100 days at risk) was greater for aGVHD than patients with no GVHD over both early and later post-transplant periods. For GVHD patients, among the infections developed from onset of aGVHD through 80 days of treatment, and until 1-year following transplantation, SS and SD patients had fewer bacterial and viral infections than SR patients. The overlap of non-relapse mortality between SS and SD GVHD patients is a function of SD GVHD being responsive to steroid therapy, even if continued therapy is required. In summary, while valid goals may include reducing unneeded antibacterial antibiotic therapy and preserving microbiome diversity, these data suggest that anti-infective therapy is justified by the density of infections observed during active GVHD treatment.

Monoclonal antibodies used for the management of haematological disorders

INTRODUCTION

Monoclonal antibodies Ab (MoAb) are increasingly becoming part of therapeutic armamentarium for haematologists and haemato-oncologists. This review brings together commonly used antibodies in one place for brevity and novel understanding.

AREAS COVERED

Pubmed and Scopus databases were explored focusing on MoAb in clinical haematological practice. Emphasis was given to current review articles. The data base was searched from 1997 till present. 24 different antibodies, most of which are in use were discussed. Antibodies are used for diverse conditions i.e. malignant and benign haematological conditions, treatment at various phases of stem cell transplantation. These antibodies were used both alone or in combination with various chemotherapy, targeted small molecules or as immunoconjugates. Some of the side effect profiles of these antibodies were common and some were unique. Unusual infections or organ dysfunctions were noted. Improved function of antibodies by protein engineering is also advancing rapidly. Dosage, frequency and route of administration depended on the convenience and condition for which the antibody is used.

EXPERT OPINION

: MoAbs are increasingly used in haematology practice either alone or in combination with other types of therapy for improved out come in various haematological conditions.

Established and Emerging Treatments of Skin GvHD

Graft-versus-host disease (GvHD) of the skin is a severe allo-immune reaction and complication following allogeneic stem cell transplantation. Over the past years, intensive pre-clinical research has led to an improved understanding of the pathophysiology of acute and to a lesser extend chronic GvHD. This has translated into the approval of several new agents for the treatment of both forms of GvHD. This review summarizes the most recent advances in underlying pathomechanisms, clinical trials and newly approved agents for GvHD, with a special focus on skin involvement.

Hematopoietic Cell Transplantation, Version 2.2020, NCCN Clinical Practice Guidelines in Oncology

Hematopoietic cell transplantation (HCT) involves the infusion of hematopoietic progenitor cells into patients with hematologic disorders with the goal of re-establishing normal hematopoietic and immune function. HCT is classified as autologous or allogeneic based on the origin of hematopoietic cells. Autologous HCT uses the patient's own cells while allogeneic HCT uses hematopoietic cells from a human leukocyte antigen-compatible donor. Allogeneic HCT is a potentially curative treatment option for patients with certain types of hematologic malignancies, and autologous HCT is primarily used to support patients undergoing high-dose chemotherapy. Advances in HCT methods and supportive care in recent decades have led to improved survival after HCT; however, disease relapse and posttransplant complications still commonly occur in both autologous and allogeneic HCT recipients. Allogeneic HCT recipients may also develop acute and/or chronic graft-versus-host disease (GVHD), which results in immune-mediated cellular injury of several organs. The NCCN Guidelines for Hematopoietic Cell Transplantation focus on recommendations for pretransplant recipient evaluation and the management of GVHD in adult patients with malignant disease.

A phase 1 trial of itacitinib, a selective JAK1 inhibitor, in patients with acute graft-versus-host disease

Acute graft-versus-host disease (aGVHD) following allogeneic hematopoietic cell transplantation (HCT) is a primary cause of nonrelapse mortality and a major barrier to successful transplant outcomes. Itacitinib is a Janus kinase (JAK)1-selective inhibitor that has demonstrated efficacy in preclinical models of aGVHD. We report results from the first registered study of a JAK inhibitor in patients with aGVHD. This was an open-label phase 1 study enrolling patients aged ≥18 years with first HCT from any source who developed grade IIB to IVD aGVHD. Patients with steroid-naive or steroid-refractory aGVHD were randomized 1:1 to itacitinib 200 mg or 300 mg once daily plus corticosteroids. The primary endpoint was safety and tolerability; day 28 overall response rate (ORR) was the main secondary endpoint. Twenty-nine patients (200 mg, n = 14; 300 mg, n = 15) received ≥1 dose of itacitinib and were included in safety and efficacy assessments. One dose-limiting toxicity was reported (grade 3 thrombocytopenia attributed to GVHD progression in a patient receiving 300 mg itacitinib with preexisting thrombocytopenia). The most common nonhematologic treatment-emergent adverse event was diarrhea (48.3%, n = 14); anemia occurred in 11 patients (38%). ORR on day 28 for all patients in the 200-mg and 300-mg groups was 78.6% and 66.7%, respectively. Day 28 ORR was 75.0% for patients with treatment-naive aGVHD and 70.6% in those with steroid-refractory aGVHD. All patients receiving itacitinib decreased corticosteroid use over time. In summary, itacitinib was well tolerated and demonstrated encouraging efficacy in patients with steroid-naive or steroid-refractory aGVHD, warranting continued clinical investigations. This trial was registered at www.clinicaltrials.gov as #NCT02614612.

Experimental Pharmaceuticals for Steroid-Refractory Acute Graft-versus-Host Disease

Acute GVHD (aGVHD) is a significant complication after allogeneic hematopoietic cell transplantation (HCT), occurring in up to 70% of HCT recipients. Steroid-refractory aGVHD represents a subset of patients failing initial therapy and is particularly morbid, with only 30% of patients surviving long term. Better therapies are urgently required for these patients. Here, we discuss recent advancements in the management of SR-aGVHD. We review the currently available therapies for SR-aGVHD including the results of the REACH1 and REACH2 trials, which provide the basis for the use of ruxolitinib for the treatment of SR-aGVHD. We additionally discuss newer agents under clinical investigation and will highlight the niche these agents may fill to further improve outcomes in aGVHD patient care.

Cutaneous manifestations of acute and chronic graft-versus-host disease

Graft-versus-host disease (GvHD) is a commonly occurring immunological reaction and frequent complication following allogeneic hematopoietic stem cell transplantation. Its highly diverse manifestations including skin involvement as the most common appearance of GvHD, can dramatically influence patient's quality of life, in particular in the chronic stage, in addition to patient's decreased survival outcome. Hence, the role of the dermatologist has become very crucial in an interdisciplinary setting, particularly since appearances of GvHD in the skin can be multifaceted and challenging. Clinical manifestation of the acute GvHD (aGvHD) is limited to erythematous maculopapular rash and oral mucosal lesions while the chronic form manifests in a wider range in a localized area or disseminated including involvement of nail, scalp and genital area. This article aims to provide a comprehensive overview on the variable cutaneous presentations of acute and chronic GvHD for a proper and early diagnosis on the one hand, and to discuss updated therapeutic options for both acute and chronic GvHD on the other hand, to initiate an adequate treatment to obtain the most beneficial clinical outcome.

Ruxolitinib in children with steroid-refractory acute graft-versus-host disease: A retrospective multicenter study of the pediatric group of SFGM-TC

BACKGROUND

We conducted a national multicenter retrospective study in France to evaluate the efficacy and tolerance of ruxolitinib in children with steroid-refractory acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplant.

PROCEDURE

Patients were recruited from the 15 pediatric transplantation centers. Transplanted patients were eligible if they met the following criteria: aged ≤ 18 years at transplantation, receiving a myeloablative allogeneic hematopoietic stem cell transplant, having an aGVHD of grade ≥2, and treated with ruxolitinib for steroid-refractory aGVHD.

RESULTS

Twenty-nine patients received ruxolitinib for steroid-refractory aGVHD. Six patients achieved a complete response at day 28 after the start of treatment but finally 19 patients (65.5%) achieved a complete response (CR) with a median delay of 41 days (5-93 days). Two patients had a partial response. All patients who achieved CR or partial response discontinued corticosteroid treatment. Eight patients showed treatment failure. The overall response rate was 72.4%. Twenty-three of 29 patients were alive at a median follow-up of 685 days (177-1042 days) after the hematopoietic stem cell transplantation. Viral replication was observed in 41.4% of cases. We did not observe severe hematological adverse events and cytopenia requiring a modification of ruxolitinib doses always resolved. The median initial dose of ruxolitinib was 12.6 mg/m² /day with an important range. We could not demonstrate any relationship between initial dose and effectiveness.

CONCLUSION

Ruxolitinib may constitute a promising second-line treatment for children with steroid-refractory aGVHD that should be validated in a prospective large-scale pharmacokinetic and efficacy trial.

Use of unapproved or off-label drugs in Japan for the treatment of graft-versus-host disease and post-transplant viral infection

Many drugs are used for unapproved indications in Japan for post hematopoietic stem cell transplant (HCT) complications. To investigate unapproved or off-label drug usage for graft-versus-host disease (GVHD) and virus infections after allogeneic HCT, we analyzed the data of Japanese HCT registry. Between 2006 and 2017, 39,941 adults and children received HCT for a variety of disease and their transplant data were captured in the registry. Among them, 14,687 and 8914 patients receiving treatment for acute and/or chronic GVHD, 24,828 patients with cytomegalovirus (CMV) infection or receiving therapies for CMV, and 4943 who received treatment for other viral infections were included in the analyses of off-label or unapproved drugs. For GVHD, mycophenolate mofetil was the most frequently used off-label drug, followed by beclomethasone, infliximab, and etanercept. For viral infections other than CMV, foscarnet was the most frequently used off-label drug. Cidofovir, which is not approved for use in Japan, was mainly used for adenovirus infection. This study demonstrated that numerous off-label and unapproved drugs have been used as key drugs for GVHD and post-transplant viral infection, and the real world date in the transplant registry may serve as an important asset to regulatory purposes.

Fungal infection risks associated with the use of cytokine antagonists and immune checkpoint inhibitors

IMPACT STATEMENT

The risk of opportunistic infections due to fungi is relatively less well addressed in patients receiving biologic agents, compared with other opportunistic bacterial and viral infections. There is a lack of consensus guideline on the screening, prophylaxis, and management of fungal infection in patients anticipated to receive or actively receiving biologic therapy. In addition, invasive mycosis in immunocompromised patients is associated with high mortality and morbidity. This review highlighted the risk of fungal infection in patients receiving cytokine antagonists and immune checkpoint inhibitors, two big categories of biologic agents that are widely used in the treatment of various autoimmune and malignant conditions, often in combination with other immunomodulatory or immunosuppressive agents but also as standalone therapy. The adverse outcomes of opportunistic fungal infection in these patients can be reduced by heightened awareness, active case finding, and prompt treatment.

Can we use interleukin-6 (IL-6) blockade for coronavirus disease 2019 (COVID-19)-induced cytokine release syndrome (CRS)?

The emergent outbreak of coronavirus disease 2019 (COVID-19) has caused a global pandemic. Acute respiratory distress syndrome (ARDS) and multiorgan dysfunction are among the leading causes of death in critically ill patients with COVID-19. The elevated inflammatory cytokines suggest that a cytokine storm, also known as cytokine release syndrome (CRS), may play a major role in the pathology of COVID-19. However, the efficacy of corticosteroids, commonly utilized antiinflammatory agents, to treat COVID-19-induced CRS is controversial. There is an urgent need for novel therapies to treat COVID-19-induced CRS. Here, we discuss the pathogenesis of severe acute respiratory syndrome (SARS)-induced CRS, compare the CRS in COVID-19 with that in SARS and Middle East respiratory syndrome (MERS), and summarize the existing therapies for CRS. We propose to utilize interleukin-6 (IL-6) blockade to manage COVID-19-induced CRS and discuss several factors that should be taken into consideration for its clinical application.

Biosimilar infliximab administration for the management of acute graft-versus-host disease

INTRODUCTION

Acute graft-versus-host disease (aGVHD) is a significant immune-mediated complication of allogeneic hematopoietic stem cell transplant (HSCT). Despite prophylactic immunosuppression, the incidence of grades II-IV aGVHD post-HSCT varies from 20 to 80%. Tumor necrosis factor (TNF) is an important cytokine involved in the pathogenesis of GVHD, and medications such as infliximab (Remicade®) have been utilized as second-line treatment options in patients with steroid-refractory GHVD. Infliximab-dyyb (Inflectra®) and infliximab-qbtx (Ixifi®) are biosimilars approved by the FDA for a variety of autoimmune disorders. This is the first case report documenting the utility of infliximab-dyyb and -qbtx for the management of steroid-refractory aGVHD.

CASE REPORT

We report the post-transplant course of three patients treated with infliximab biosimilars as a part of therapy for management of steroid-refractory aGVHD.

MANAGEMENT AND OUTCOME

Steroid-refractory aGVHD is associated with poor prognosis and its management, as highlighted in our three patient cases, and can be very diverse often requiring different therapeutic modalities which overlap in administration.

DISCUSSION

In these patients with steroid-refractory aGVHD, we were able to show that infliximab biosimilars could be used in lieu of the reference infliximab product. Although we had important limitations, this case report supports the use of anti-TNF agents in highly mortal steroid-refractory acute GI GVHD and that replacement of infliximab with its biosimilars is feasible.

Treatment and unmet needs in steroid-refractory acute graft-versus-host disease

Acute graft-versus-host disease (aGVHD) is a common complication of allogeneic hematopoietic stem cell transplantation (alloHCT) and is a major cause of morbidity and mortality. Systemic steroid therapy is the first-line treatment for aGVHD, although about half of patients will become refractory to treatment. As the number of patients undergoing alloHCT increases, developing safe and effective treatments for aGVHD will become increasingly important, especially for those whose disease becomes refractory to systemic steroid therapy. This paper reviews current treatment options for patients with steroid-refractory aGVHD and discusses data from recently published clinical studies to outline emerging therapeutic strategies.

Ruxolitinib: a potential treatment for corticosteroid refractory acute graft-versus-host disease

INTRODUCTION

Allogeneic transplantation represents a potentially curative procedure for various lethal conditions; however, it is associated with serious immune mediated complications. The most serious complication is graft-versus-host disease (GVHD). Acute GVHD (aGVHD) is unresponsive to initial corticosteroid therapy in ~40% of cases. Corticosteroid-refractory aGVHD (CR-aGVHD) represents a significant unmet need with nearly 60% mortality in patients developing this state.

AREAS COVERED

We review landmark trials which led to the US FDA approval of Ruxolitinb for the treatment of CR-aGVHD. Ruxolitinib phosphate is a Janus Kinase 1 and 2 inhibitor which inhibits pro-inflammatory signaling, and modulates T-cell subsets to an anti-inflammatory phenotype. Ruxolitinib was recently prospectively studied for the treatment of CR-aGVHD in the REACH1 trial, which added Ruxolitinib to corticosteroid therapy. This trial demonstrated favorable results with 73% of patients ultimately responding. Among responders, over 70% remained alive at 6 months. These results led to the US FDA to approve ruxolitinib as treatment for CR-aGVHD, the first approval of its kind.

EXPERT OPINION

Ruxolitinib represents the standard option for CR-aGVHD. Future studies should identify patients less likely to respond to ruxolitinib and/or focus on a more targeted approaches to reduce infectious complications and cytopenias seen with this drug.

Therapeutic options for steroid-refractory acute and chronic GVHD: an evolving landscape

Introduction: The traditional therapeutic modalities to manage SR-acute GVHD have focused on the inhibition of the alloreactive T-cell response, while in the setting of SR-chronic GVHD the focus has been on a combination of T-cell and B-cell targeting strategies. However, new therapeutic modalities have shown promise. The purpose of this review is to summarize the current treatment landscape of SR-acute and chronic GVHD.Areas covered: A systematic search of MEDLINE, EMBASE, and clinicaltrials.gov databases for published articles, abstracts, and clinical trials pertaining to available therapeutic modalities for SR-acute and SR-chronic GVHD was conducted. Also highlighted is a number of ongoing clinical trials in both SR-acute and SR-chronic GVHD with strategies targeting the JAK-1/2 pathway, the Treg:Tcon ratio, the immunomodulation mediated by mesenchymal stem cells, and the gut microbiome, among others. Expert opinion: Ruxolitinib has emerged as the preferred therapeutic modality for SR-acute GVHD, with alpha-1-antitrypsin and extracorporeal photophoresis (ECP) being reasonable alternatives. Ruxolitinib and Ibrutinib are among the preferred options for SR-chronic GVHD, with ECP being a viable alternative particularly if the skin is involved. A number of novel therapeutic modalities, including those enhancing the activity of regulatory T-cells have shown great promise in early phase trials of SR-chronic GVHD.

Ruxolitinib add-on in corticosteroid-refractory graft-vs-host disease after allogeneic stem cell transplantation: Results from a retrospective study on 38 Chinese patients

BACKGROUND

Graft-vs-host disease (GVHD) is a major cause of mortality after allogeneic hematopoietic stem cell transplantation. Some patients have steroid-refractory (SR) GVHD.

AIM

To evaluate the effect and safety of ruxolitinib add-on in the treatment of patients with SR acute (a) and chronic (c) GVHD.

METHODS

We retrospectively analyzed 38 patients administered ruxolitinib add-on to standard immunosuppressive therapy for SR-aGVHD or SR-cGVHD following allogeneic hematopoietic stem cell transplantation. Ruxolitinib was administered 5-10 mg/d depending on disease severity, patient status, and the use of anti-fungal drugs. Overall response rate, time to best response, malignancy relapse rate, infection rate, and treatment-related adverse events were assessed.

RESULTS

The analysis included 10 patients with SR-aGVHD (grade III/IV, n = 9) and 28 patients with SR-cGVHD (moderate/severe, n = 24). For the SR-aGVHD and SR-cGVHD groups, respectively: Median number of previous GVHD therapies was 2 (range: 1-3) and 2 (1-4); median follow-up was 2.5 (1.5-4) and 5 (1.5-10) mo; median time to best response was 1 (0.5-2.5) and 3 (1-9.5) mo; and overall response rate was 100% (complete response: 80%) and 82.1% (complete response: 10.7%) with a response observed in all GVHD-affected organs. The malignancy relapse rates for the SR-aGVHD and SR-cGVHD groups were 10.0% and 10.7%, respectively. Reactivation rates for cytomegalovirus, Epstein-Barr virus, and varicella-zoster virus, respectively, were 30.0%, 10.0%, and 0% for the SR-aGVHD group and 0%, 14.3%, and 7.1% for the SR-cGVHD group.

CONCLUSION

Ruxolitinib add-on was effective and safe as salvage therapy for SR-GVHD.

CD4+FOXP3+ Regulatory T Cell Therapies in HLA Haploidentical Hematopoietic Transplantation

Since their discovery CD4⁺FOXP3⁺ regulatory T cells (Tregs) represented a promising tool to induce tolerance in allogeneic hematopoietic cell transplantation. Preclinical models proved that adoptive transfer of Tregs or the use of compounds that can favor their function in vivo are effective for prevention and treatment of graft-vs.-host disease (GvHD). Following these findings, Treg-based therapies have been employed in clinical trials. Adoptive immunotherapy with Tregs effectively prevents GvHD induced by alloreactive T cells in the setting of one HLA haplotype mismatched hematopoietic transplantation. The absence of post transplant pharmacologic immunosuppression unleashes T-cell mediated graft-vs.-tumor (GvT) effect, which results in an unprecedented, almost complete control of leukemia relapse in this setting. In the present review, we will report preclinical studies and clinical trials that demonstrate Treg ability to promote donor engraftment, protect from GvHD and improve GvT effect. We will also discuss new strategies to further enhance in vivo efficacy of Treg-based therapies.

Resolution of acute intestinal graft-versus-host disease

Allogeneic transplantation of hematopoietic stem cells (allo-HCT) represents an increasingly employed therapeutic approach to potentially cure patients suffering from life-threatening malignant and autoimmune disorders. Despite its lifesaving potential, immune-mediated allo-reactivity inherent to the allogeneic transplantation can be observed within up to 50% of all allo-HCT patients regularly resulting in the manifestation of acute and/or chronic graft-versus-host disease (GvHD). Mechanistically, especially donor T cells are assumed to chiefly drive inflammation that can occur in virtually all organs, with the skin, liver, and gut representing as the most frequently affected anatomic sites. Especially in the presence of intestinal manifestations of GvHD, the risk that the disease takes a life-threatening, potentially fatal course is significantly increased. In the light of a rapid gain of knowledge in respect to decode innate and adaptive immunity related mechanisms as, e.g., cytokine networks, intracellular signaling pathways or environmental triggers as, e.g., the intestinal microbiota and the development of novel therapeutic approaches, detailed insight into endogenous mechanisms seeking to counterbalance the proinflammatory machinery or to proactively foster signals promoting the resolution of allo-driven intestinal inflammation is emerging. Here, we seek to highlight the key aspects of those mechanisms involved in and contributing to the resolution of GvHD-associated intestinal inflammation. Concomitantly, we would like to briefly outline and discuss promising future experimental targets suitable to be therapeutically employed to directionally deflect the tissue response from a proinflammatory to an inflammation-resolving type of intestinal GvHD after allo-HCT.

Worldwide Network for Blood and Marrow Transplantation (WBMT) perspective: the role of biosimilars in hematopoietic cell transplant: current opportunities and challenges in low- and lower-middle income countries

Health care costs attributed to biologics have increased exponentially in the recent years, thus biosimilars offer a possible solution to limit costs while maintaining safety and efficacy. Reducing expenditure is vital to health care especially in developing countries where affordability and access to health care is a major challenge. We discuss the opportunities and the challenges of biosimilars in the field of hematopoietic cell transplantation (HCT) in low- and lower-middle income countries. Developing countries can potentially invest in the forecasted costs reduction by utilizing biosimilars. This can be used to decrease the costs of procedures such as HCT, which is a rapidly growing field in many developing regions. The introduction of biosimilars in the developing regions faces many challenges which include, but are not limited to: legal and regulatory issues, lack of research infrastructure, and the presence of educational barriers. Thus, collaborative efforts are needed to ensure an effective and safe introduction of biosimilars into low- and lower-middle income countries.

TNFR2 signaling modulates immunity after allogeneic hematopoietic cell transplantation

Tumor necrosis factor-α (TNF-α) signaling through TNF receptor 2 (TNFR2) plays a complex immune regulatory role in allogeneic hematopoietic cell transplantation (HCT). TNF-α is rapidly released in the circulation after the conditioning regimen with chemotherapy and/or radiotherapy. It activates the function of donor alloreactive T cells and donor Natural Killer cells and promotes graft versus tumor effects. However, donor alloreactive T cells also attack host tissues and cause graft versus host disease (GVHD), a life-threatening complication of HCT. Indeed, anti-TNF-α therapy has been used to treat steroid-refractory GVHD. Recent studies have highlighted another role for TNFR2 signaling, as it enhances the function of immune cells with suppressive properties, in particular CD4⁺Foxp3⁺ regulatory T cells (Tregs). Various clinical trials are employing Treg-based treatments to prevent or treat GVHD. The present review will discuss the effects of TNFR2 signaling in the setting of allogeneic HCT, the implications for the use of anti-TNF-α therapy to treat GVHD and the clinical perspectives of strategies that specifically target this pathway.

Safety and Effectiveness of Vedolizumab in Patients with Steroid-Refractory Gastrointestinal Acute Graft-versus-Host Disease: A Retrospective Record Review

Allogeneic hematopoietic cell transplantation (allo-HCT) can be curative in patients with hematologic malignancies but carries a significant risk of graft-versus-host disease (GVHD). There are no standard treatments for steroid-refractory (SR) gastrointestinal (GI) acute GVHD (aGVHD). This multicenter, international, retrospective medical record review aimed to evaluate the off-label use of vedolizumab, a gut-selective immunomodulator, for treating SR GI aGVHD. Data were collected from patients' medical records; criteria for extraction included no more than 1 allo-HCT and at least 1 dose of vedolizumab as treatment for SR GI aGVHD (ie, stage 1 to 4 GI aGVHD following ≥1 previous treatment regimen(s) containing ≥1 mg/kg methylprednisolone or equivalent). Descriptive analyses of response rate, overall survival (OS), and serious adverse effects (SAEs) were performed. Twenty-nine patients were identified from 7 sites who had received 1 to 10 doses of vedolizumab 300 mg i.v. (median 3 doses) as treatment for SR GI aGVHD. The overall response rate at 6 to 10 weeks after vedolizumab initiation was 64%, and OS at 6 months was 54%. There were 29 SAEs, including 12 infections; 3 SAEs were considered possibly related to vedolizumab, 2 of which were infections. Thirteen SAEs were fatal, 1 of which was possibly vedolizumab-related. There were 8 nonserious infections and 1 serious infection with confirmed GI origin in 8 patients; there was no apparent pattern in the timing of these infections relative to the initiation of vedolizumab treatment. Further data on the efficacy and safety of vedolizumab in this setting from prospective trials are needed.

Tumor Necrosis Factor α and Regulatory T Cells in Oncoimmunology

Tumor necrosis factor α (TNF) is a potent pro-inflammatory cytokine that has deleterious effect in some autoimmune diseases, which led to the use of anti-TNF drugs in some of these diseases. However, some rare patients treated with these drugs paradoxically develop an aggravation of their disease or new onset autoimmunity, revealing an immunosuppressive facet of TNF. A possible mechanism of this observation is the direct and positive effect of TNF on regulatory T cells (Tregs) through its binding to the TNF receptor type 2 (TNFR2). Indeed, TNF is able to increase expansion, stability, and possibly function of Tregs via TNFR2. In this review, we discuss the role of TNF in graft-versus-host disease as an example of the ambivalence of this cytokine in the pathophysiology of an immunopathology, highlighting the therapeutic potential of triggering TNFR2 to boost Treg expansion. We also describe new targets in immunotherapy of cancer, emphasizing on the putative suppressive effect of TNF in antitumor immunity and of the interest of blocking TNFR2 to regulate the Treg compartment.

The Effect of TNF-α on Regulatory T Cell Function in Graft-versus-Host Disease

FoxP3⁺ regulatory T cells (Tregs) are a subset of CD4⁺ T cells that can suppress proliferation and effector functions of T cells, B cells, NK cells, and antigen-presenting cells. Treg deficiency causes dramatic immunologic disease in both animal models and humans. As they are capable to suppress the function and the proliferation of conventional CD4⁺ and CD8⁺ T cells, Treg-based cell therapies are under evaluation for the treatment of various autoimmune diseases and are currently employed to prevent graft-versus-host disease (GvHD) in clinical trials of hematopoietic stem cell transplantation. Even though tumor necrosis factor-α (TNF-α) is well known for its pro-inflammatory role, recent studies show that it promotes Treg activation and suppressive function. In the present review, we discuss the role of TNF-α in Treg function and the possible implications on the actual treatments for immune-mediated diseases, with a particular attention to GvHD.