The Addition of Sirolimus to GVHD Prophylaxis After Allogeneic Hematopoietic Stem Cell Transplantation: A Meta-Analysis of Efficacy and Safety

Thrombotic microangiopathy after kidney transplantation: Expanding etiologic and pathogenetic spectra

Thrombotic microangiopathy (TMA) is an uncommon but serious complication that not only affects native kidneys but also transplanted kidneys. This review is specifically focused on post-transplant TMA (PT-TMA) involving kidney transplant recipients. Its reported prevalence in the latter population varies from 0.8% to 14% with adverse impacts on both graft and patient survival. It has many causes and associations, and the list of etiologic agents and associations is growing constantly. The pathogenesis is equally varied and a variety of patho genetic pathways lead to the development of microvascular injury as the final common pathway. PT-TMA is categorized in many ways in order to facilitate its management. Ironically, more than one causes are contributory in PT-TMA and it is often difficult to pinpoint one particular cause in an individual case. Pathologically, the hallmark lesions are endothelial cell injury and intravascular thrombi affecting the microvasculature. Early diagnosis and classification of PT-TMA are imperative for optimal outcomes but are challenging for both clinicians and pathologists. The Banff classification has addressed this issue and has developed minimum diagnostic criteria for pathologic diagnosis of PT-TMA in the first phase. Management of the condition is also challenging and still largely empirical. It varies from simple maneuvers, such as plasmapheresis, drug withdrawal or modification, or dose reduction, to lifelong complement blockade, which is very expensive. A thorough understanding of the condition is imperative for an early diagnosis and quick treatment when the treatment is potentially effective. This review aims to increase the awareness of relevant stakeholders regarding this important, potentially treatable but under-recognized cause of kidney allograft dysfunction.

Janus kinase inhibition in the treatment and prevention of graft-versus-host disease

Graft-versus-host disease (GVHD) is a significant cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). For many years, corticosteroids have been the mainstay treatment for GVHD, but cases of steroid-refractory GVHD and the severe adverse effects of high-dose corticosteroids have increased the need for preventative and therapeutic strategies for GVHD. Due to the nature of alloreactive T cells, GVHD is inherently linked to the graft-versus-leukemia (GVL) effect, the therapeutic driving force behind stem cell transplantation. A considerable clinical challenge is to preserve GVL while suppressing GVHD. The field of GVHD research has greatly expanded over the past decades, including advancements in T cell modulation and depletion, antibody therapies, chemotherapeutics, cellular therapies, and Janus kinase inhibition. In this review, we discuss current approaches and advances in the prophylaxis and treatment of GVHD with a focus on new emerging advancements in Janus kinase inhibitor therapy.

Optimizing the therapeutic window of sirolimus by monitoring blood concentration for the treatment of immune thrombocytopenia

Previous studies have demonstrated that sirolimus (SRL) is an effective agent for the treatment of refractory/relapsed (R/R) ITP. However, the therapeutic window of sirolimus in the treatment of ITP has not been established. As the toxicity of sirolimus increases with higher blood concentrations, it is crucial to determine the optimal therapeutic concentration of SRL for the treatment of ITP. Thus, in this study, we used a retrospective cohort of ITP patients treated with sirolimus to propose the therapeutic dosage window for sirolimus. A total of 275 laboratory results of SRL blood concentration from 63 ITP patients treated with SRL were analyzed retrospectively. The ITP patients were divided into five groups based on their SRL blood concentration: 0-4 ng/ml, 4-8 ng/ml, 8-12 ng/ml, 12-16 ng/ml and ≥16 ng/ml. In addition to the SRL blood concentration, platelet counts and adverse events that occurred during the first 6 weeks of SRL treatment were analyzed. These findings were then used to establish the decision matrix tables and ROC curves, which helped identify the therapeutic window of SRL. Based on the values and trends of true-positive rate (TPR) and false-positive rate (FPR) in the ROC curve, patients who achieved a SRL blood concentration of 4-12 ng/ml displayed a higher response rate compared to those with a SRL concentration of 0-4 ng/ml or ≥16ng/ml. Additionally, the response rate was better for patients with a SRL concentration of 8-12 ng/ml compared to 4-8 ng/ml. Adverse events were related to the concentration of SRL; however, there was no significant difference in the incidence of adverse events between the concentrations of 4-8 ng/ml and 8-12 ng/ml (P > .05). Regression analysis suggested that the concentration of SRL correlated with the patient's age, PLT count at the start of SRL administration, and the dose of SRL. It is suggested that the optimal blood concentration of SRL monotherapy for managing ITP is 8-12 ng/ml. This range may achieve a favorable balance between clinical efficacy and the severity of adverse events.

[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.

Recent advances in graft-versus-host disease

Acute and chronic graft-versus-host disease (GVHD) continue to present a significant challenge to physicians, accounting for considerable haematopoietic stem cell transplant (HSCT)-related morbidity and mortality, particularly those patients with steroid-refractory disease. In this review, we discuss recent advances in understanding the underlying pathophysiology, prevention and management of acute and chronic GVHD. Barriers to progress include the difficulty in obtaining high-quality evidence with sufficient patient numbers to identify optimal preventative and treatment strategies, with the heterogeneity of multiple patient, donor, graft and transplant-related factors, in addition to limited availability of human tissue to study the underlying pathophysiology, particularly in steroid-refractory disease. Continued collaborative efforts to improve our understanding of the pathophysiology involved, particularly in steroid-refractory disease, identification of biomarkers to permit risk stratification, and further well-designed randomised clinical trials are essential to help physicians determine optimal GVHD preventative and treatment strategies for each individual patient.

Predicting the effect of sirolimus on disease activity in patients with systemic lupus erythematosus using machine learning

WHAT IS KNOWN AND OBJECTIVES

The present study aimed to predict the effect of sirolimus on disease activity in patients with systemic lupus erythematosus (SLE) using machine learning and to recommend appropriate sirolimus dosage regimen for patients with SLE.

METHODS

The E_max model was selected for machine learning, where the evaluation indicator was the change rate of systemic lupus erythematosus disease activity index from baseline value.

RESULTS

A total 103 patients with SLE were included for modelling, where the E_max , ET₅₀ were -53.9%, 1.53 months in the final model respectively, and the evaluation of the final model was good. Further simulation found that the follow-up time to achieve 25%, 50%, 75% and 80% (plateau) E_max of sirolimus effecting on disease activity in patients with SLE were 0.51, 1.53, 4.59 and 6.12 months, respectively. In addition, the sirolimus dosage was flexible and adjusted according to drug concentration, where the intersection of sirolimus concentration range included in this study was about 8-10 ng/ml.

WHAT IS NEW AND CONCLUSIONS

This study was the first time to predict the effect of sirolimus on disease activity in patients with SLE and in order to achieve better therapeutic effect maintaining a concentration of 8-10 ng/ml sirolimus for at least 6.12 months was necessary.