Photopheresis in pediatric graft-versus-host disease after allogeneic marrow transplantation: clinical practice guidelines based on field experience and review of the literature

Clinical Results of Extracorporeal Photopheresis

Extracorporeal photopheresis (ECP) is a combination of leukapheresis and photodynamic therapy in which blood is treated with photoactivable drugs which are then activated with ultraviolet light and re-infused to the patient. It has been used successfully for more than 30 years in the treatment of erythrodermic cutaneous T-cell lymphoma (CTCL) and over 20 years for chronic graft-versus-host disease (GVHD). ECP has also shown promising results in the treatment of acute GVHD and other T-cell-mediated diseases, including systemic sclerosis, treatment and prevention of solid organ rejection, and more recently Crohn's disease. The use of ECP may allow a significant reduction or even discontinuation of corticosteroids and/or other immunosuppressants, thus leading to reduced long-term morbidity and mortality and improved overall survival. ECP is a well-tolerated therapy. No significant side effects have been reported during the last 30 years. It has been shown that ECP is not associated with an increased incidence of infections, malignancies, or recurrence of underlying malignant disease, neither during short-term nor during long-term therapy.

Extracorporeal photopheresis, a therapeutic option for cutaneous T-cell lymphoma and immunological diseases: state of the art

INTRODUCTION

Extracorporeal photopheresis (ECP) has been extensively used for the treatment of immune-mediated diseases for over 20 years and has a consistent and predictable safety profile with long-term use. Documenting the efficacy of ECP as therapeutic treatment has long been a matter of importance for physicians.

AREAS COVERED

The authors reviewed publications in this field with the goal of providing an overview of this therapeutic approach.

EXPERT OPINION

ECP is efficacious in a high percentage of those cutaneous T-cell lymphoma patients who have circulating malignant T cells in the context of a still-near-normal immune competence. From the side of graft-versus-host disease (GVHD), the use of ECP showed a clinical benefit in patients with steroid-refractory acute GVHD (aGVHD) and it is believed that ECP deserves to be evaluated as part of a combination strategy in first-line therapy of aGVHD. In chronic GHVD, the published data show that ECP can be effective in extensive and long-standing disease even when treatment is initiated at an advanced stage after conventional immunosuppressive and corticosteroid therapy has failed. ECP should be considered most beneficial for patients with predominantly mucocutaneous chronic GVHD. The fields of application of the procedure could be vast, and could also include autoimmune and metabolic diseases. The most important methodological issues which affect ECP evaluation is that the large majority of data about ECP result from single-arm observational series and the significant efficacy is mainly based on small and retrospective studies. ECP has never been proved to offer any survival advantage in a context of a randomized trial and the above-mentioned limitation also affects the accuracy of many biological modifications observed during ECP. Starting from these considerations, the need of a prospective randomized study becomes increasingly urgent.

Nonpharmacologic treatment of chronic graft-versus-host disease in children and adolescents

Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for many children with life-threatening diseases. One of the most significant long-term complications of transplantation is chronic graft-versus-host disease (cGVHD). Although the rates of cGVHD after HSCT are lower in the pediatric population than in adults, cGVHD remains a significant cause of morbidity and mortality. Medicines used to prevent and treat cGVHD remain unsatisfactory, with protracted use of immune suppression necessary and high rates of first-line treatment failure. Efforts to improve salvage treatment are urgently required. Nonpharmacologic strategies attempt to modulate the cellular inflammation response and possibly allow reduction or cessation of immunosuppressive drugs. Mesenchymal stromal cells (MSC) have been shown in vitro to mediate a wide variety of immune responses. MSC have been used in the prophylaxis of acute GVHD (aGVHD) and for the treatment of established steroid refractory aGVHD and, more recently, in the management of cGVHD. Extracorporeal photochemotherapy (ECP) has shown promising efficacy in graft-versus-host disease, and may allow a significant reduction in the use of systemic steroids and other immunosuppressants, reducing long-term morbidity and mortality. The accumulated experience shows ECP to be well tolerated, with no clinically significant side effects.

Bronchiolitis obliterans after allo-SCT: clinical criteria and treatment options

Bronchiolitis obliterans (BO) following allogeneic haematopoietic SCT (HSCT) is a serious complication affecting 1.7-26% of the patients, with a reported mortality rate of 21-100%. It is considered a manifestation of chronic graft-versus-host disease, but our knowledge of aetiology and pathogenesis is still limited. Diagnostic criteria are being developed, and will allow more uniform and comparable research activities between centres. At present, no randomised controlled trials have been completed that could demonstrate an effective treatment. Steroids in combination with other immunosuppressive drugs still constitute the backbone of the treatment strategy, and results from our and other centres suggest that monthly infusions of high-dose pulse i.v. methylprednisolone (HDPM) might stabilise the disease and hinder progression. This article provides an overview of the current evidence regarding treatment options for BO and presents the treatment results with HDPM in a paediatric national HSCT-cohort.

The role of photopheresis in the treatment of graft-versus-host disease

Hematopoietic stem-cell transplantation [...]

Guidelines on the use of therapeutic apheresis in clinical practice--evidence-based approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence-based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence-based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed.

CFSE flow cytometric quantification of lymphocytic proliferation in extracorporeal photopheresis: use for quality control

Quality control is essential to validate extracorporeal photopheresis (ECP) processes. There is just one protocol based on PHA-induced proliferation. Since it involves the use of radioactive thymidine, we developed another technique using CFSE labeling. We compared the two tests in a paired series including 18 procedures. The thymidine test was valid. Once proliferation was obtained (10 patients out of 13), the CFSE test was in close agreement with it. In particular, two cases of residual proliferation after ECP were simultaneously detected by both techniques. Only the CFSE test allows targeted analysis of lymphocytes, thus identifying a surviving lymphocytic sub-population.

[Rationale for the use of extracorporeal photochemotherapy in children]

The management of immune diseases in children remains challenging, although significant advances have been made. In addition to pharmacological approaches, extracorporeal photochemotherapy (ECP) is distinctive in its ability to provide immunomodulation without immune suppression or toxicity. However, in practice, this therapy is not widely used because of logistical issues and the lack of robust clinical pediatric studies. Here, we discuss the potential clinical applications of ECP in children and emphasize the need for a rigorous and specifically pediatric clinical evaluation of ECP.

Cryopreservation of mononuclear cells before extracorporeal photochemotherapy does not impair their anti-proliferative capabilities

BACKGROUND AIMS

The clinical benefits of extracorporeal photochemotherapy (ECP) are well recognized, but its clinical use is limited by logistical difficulties, especially because of the need to perform repeated aphereses. The cryopreservation of mononuclear cells could allow maintenance of the ECP schedule while reducing the number of aphereses. The aim of this work was to assess whether previous cryopreservation impairs the immunomodulatory function of ECP-treated peripheral blood mononuclear cells (PBMC).

METHODS

Fresh or previously cryopreserved PBMC were exposed to ECP and added on day 0 into a mixed leukocyte reaction. Proliferation of alloreactive lymphocytes was measured by carboxyfluorescein succinimidyl ester (CFSE) dye dilution. Apoptosis was quantified by annexin-7AAD staining.

RESULTS

ECP-induced apoptosis was slightly increased in cryopreserved cells but the kinetics of apoptosis were similar to fresh cells. Lymphocytes stimulated in the presence of ECP-treated PBMC displayed a significant decrease in proliferation. The suppression was enforced when ECP-treated cells had been activated previously by allogeneic stimulation. Cryopreservation before ECP exposure did not impact apoptosis triggering or anti-proliferative properties of ECP-treated cells.

CONCLUSIONS

Cryopreservation before ECP does not impair the immunomodulatory effects of treated cells. These data warrant investigation of the clinical use of cryopreserved PBMC for ECP.

The use of fluid boluses to safely perform extracorporeal photopheresis (ECP) in low-weight children: a novel procedure

Apheresis procedures in small children are technically challenging and require special planning with attention to extracorporeal volume. Discontinuous procedures such as extracorporeal photopheresis (ECP) require additional consideration. Alternative methods to perform ECP have been utilized in small children that require manipulation of mononuclear cells outside the standard closed-loop system. We present a safe and feasible alternative to the procedure for children who weigh less than 40 Kg, while maintaining a closed loop, sterile system utilizing the UVAR XTS device. A retrospective chart review was performed analyzing the use of fluid boluses (normal saline in those between 20 and 40 Kg, 5% albumin in those under 20 Kg) before ECP. Eleven patients underwent 334 ECP procedures for acute and chronic graft-versus-host disease (n = 9), and for prevention of graft-versus-host disease (n = 2). Volumes of fluid boluses were calculated based on the expected extracorporeal volume during the first draw cycle. Treatments consisted of at least three draw cycles using the 125 mL bowl. The median weight was 28.5 Kg (range 19 to 39); nine of 11 required red cell transfusions to maintain adequate hematocrit. Complications attributed to ECP included tachycardia, dizziness, nausea, and hypotension; these occurred either in combination or isolation in 31% of the procedures and resolved following additional fluid boluses. Only three (0.8%) required early photoactivation due to these complications. The median time to completion of treatment was 2 h and 58 min (range 1:30 to 5:03). ECP is well tolerated in low-weight pediatric patients if hematocrit and hydration are carefully maintained.

Consensus conference on clinical practice in chronic graft-versus-host disease (GVHD): first-line and topical treatment of chronic GVHD

Chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation is still associated with significant morbidity and mortality. First-line treatment of cGVHD is based on steroids of 1 mg/kg/day of prednisone. The role of calcineurin inhibitors remains controversial, especially in patients with low risk for mortality (normal platelets counts), whereas patients with low platelets at diagnosis and/or high risk for steroid toxicity may be treated upfront with the combination of prednisone and a calcineurin inhibitor. Additional systemic immunosuppressive agents, like thalidomide, mycophenolic acid, and azathioprine, failed to improve treatment results in the primary treatment of cGVHD and are in part associated with higher morbidity, and in the case of azathioprine, with higher mortality. Despite advances in diagnosis of cGVHD as well as supportive care, half of the patients fail to achieve a long-lasting response to first-line treatment, and infectious morbidity continues to be significant. Therefore, immunomodulatory interventions with low infectious morbidity and mortality such as photopheresis need urgent evaluation in clinical trials. Beside systemic immunosuppression, the use of topical immunosuppressive interventions may improve local response rates and may be used as the only treatment in mild localized organ manifestations of cGVHD.

Consensus Conference on Clinical Practice in Chronic GVHD: Second-Line Treatment of Chronic Graft-versus-Host Disease

Steroid refractory chronic graft-versus-host disease (cGVHD) is associated with a significant morbidity and mortality. Although first-line treatment of cGVHD is based on controlled trials, second-line treatment is almost solely based on phase II trials or retrospective analyses. The consensus conference on clinical practice in cGVHD held in Regensburg aimed to achieve a consensus on the current evidence of treatment options as well as to provide guidelines for daily clinical practice. Treatment modalities are the use of steroids and calcineurin inhibitors as well as immunomodulating modalities (photopheresis, mTOR-inhibitors, thalidomide, hydroxychloroquine, vitamin A analogs, clofazimine), and cytostatic agents (mycophenolate mofetil, methotrexate, cyclophosphamide, pentostatin). Recent reports showed some efficacy of rituximab, alemtuzumab, and etanercept in selected patients. Moreover, tyrosine kinase inihibitors such as imatinib came into the field because of their ability to interfere with the platelet-derived growth factor (PDGF-R) pathway involved in fibrosis. An other treatment option is low-dose thoracoabdominal irradiation. Although different treatment options are available, the "trial-and-error system" remains the only way to identify the drug effective in the individual patient, and valid biomarkers are eagerly needed to identify the likelihood of response to a drug in advance. Moreover, the sparse evidence for most treatment entities indicates the urgent need for systematic evaluation of second-line treatment options in cGVHD.

Evaluation of pentostatin in corticosteroid-refractory chronic graft-versus-host disease in children: a Pediatric Blood and Marrow Transplant Consortium study

There is no standard therapy for steroid-refractory chronic graft-versus-host disease (GVHD). This problem is particularly daunting in children with chronic GVHD, whereby the effects of the disease and its treatment may impair normal growth and development. Children are also particularly vulnerable to failure and/or toxicity of therapy; for example, joint contractures or joint damage may result in life-long disability. The Pediatric Blood and Marrow Transplant Consortium performed a phase 2 trial of pentostatin for steroid-refractory chronic GVHD in 51 children (median age, 9.8 years) from 24 institutions. Overall response was 53% (95% confidence interval, 40%-64%), with a response of 59% (95% confidence interval, 42%-75%) in sclerosis. Thirteen subjects (25%) had toxicity requiring them to stop pentostatin. The drug had a significant steroid-sparing effect in those that responded. A trend was also observed toward increased survival at 3 years in responders versus nonresponders (69% vs 50%; P = .06). The intravenous administration of the drug ensures compliance in a patient group in which oral therapy is difficult to monitor. Pentostatin has activity in refractory chronic GVHD in children, and future studies, including treatment of children newly diagnosed with high-risk chronic GVHD, are warranted. The trial was registered at www.Clinicaltrials.gov as #NCT00144430.

Photopheresis in pediatric patients with low-body weight using the UVAR XTS system

BACKGROUND

Photopheresis (ECP) with the UVAR XTS system has been limited to patients with a body weight > 40 kg, because extracorporeal blood volumes (ECV) may exceed 15% of the total blood volumes in low-body-weight patients. Because of these instrument characteristics, the use of ECP is limited in pediatric patients.

PATIENTS AND METHODS

In 5 patients (age 4 to 15 years) with graft-versus-host disease and with a body weight between 13 and 34 kilograms, photopheresis was performed using the UVAR XTS system. In 3 patients ECP could be performed by balancing the ECV with saline infusions. In 2 patients the system was modified in that the instrument was primed with packed red cells. During the treatment, fluid balance was guaranteed by a reservoir from a transfusion bag connected in parallel.

RESULTS

Together 223 procedures were performed, among them 28 with the modification of the system. The treatments were well tolerated, and no episodes of hypotension were observed.

CONCLUSIONS

It is possible to run ECP in low-body weight patients with the UVAR XTS system.