Hypovitaminosis D Is Prevalent in Patients With Renal AL Amyloidosis and Associated With Renal Outcome.

Introduction: Vitamin D deficiency is common, but no data have been reported on vitamin D levels in light chain (AL) amyloidosis. Patients and Methods: In this exploratory study, stored serum samples from 173 patients with newly diagnosed AL amyloidosis were analyzed for vitamin studies which included 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2D] and vitamin D binding protein (DBP). Measurements were made by liquid chromatography-tandem mass spectrometry. Kidney survival and overall survival (OS) were assessed in association to vitamin D status. Results: Cardiac and kidney involvement occurred in 69% and 63% of patients, respectively. 25(OH)D deficiency (<20 ng/mL) was seen in 56.6% of the patients and was notably found among patients with heavy proteinuria (96%), hypoalbuminemia (84.3%) and morbidly obese patients (68.3%). Heavy proteinuria (>5 gr/24-h) and vitamin D supplementation were independent predictors of 25(OH)D level on nominal multivariate regression analysis. 1,25(0H)2D deficiency was noted in 37.6% of patients and was independently associated with low eGFR and hypoalbuminemia. Progression to ESRD occurred in 23.7% of evaluable patients. Patients who progressed to ESRD had lower serum 25(OH)D and 1,25(OH)2D levels compared to those who did not progress to ESRD. On a multivariate analysis, severe 25(OH)D deficiency was an independent predictor of progression to ESRD as was renal stage, while 1,25(OH)2D deficiency was not. Conclusions: Hypovitaminosis D is common in AL amyloidosis, particularly among patients with heavy proteinuria. Severe 25(OH)D deficiency at time of diagnosis predicts progression to ESRD.

Systemic immunoglobulin light chain amyloidosis.

Systemic immunoglobulin light chain amyloidosis is a protein misfolding disease caused by the conversion of immunoglobulin light chains from their soluble functional states into highly organized amyloid fibrillar aggregates that lead to organ dysfunction. The disease is progressive and, accordingly, early diagnosis is vital to prevent irreversible organ damage, of which cardiac damage and renal damage predominate. The development of novel sensitive biomarkers and imaging technologies for the detection and quantification of organ involvement and damage is facilitating earlier diagnosis and improved evaluation of the efficacy of new and existing therapies. Treatment is guided by risk assessment, which is based on levels of cardiac biomarkers; close monitoring of clonal and organ responses guides duration of therapy and changes in regimen. Several new classes of drugs, such as proteasome inhibitors and immunomodulatory drugs, along with high-dose chemotherapy and autologous haematopoietic stem cell transplantation, have led to rapid and deep suppression of amyloid light chain production in the majority of patients. However, effective therapies for patients with advanced cardiac involvement are an unmet need. Passive immunotherapies targeting clonal plasma cells and directly accelerating removal of amyloid deposits promise to further improve the overall outlook of this increasingly treatable disease.

Clinical trials evaluating potential therapies for light chain (AL) amyloidosis.

INTRODUCTION: The field of systemic amyloidosis is experiencing major advances in diagnostic and prognostic methods coupled with a growing availability in treatment options. AREAS COVERED: Treatment of AL amyloidosis traditionally targeted the clonal plasma cells, in order to block further production of amyloidogenic light chains. Currently, a research focus is placed on targeting the already formed amyloid deposits using monoclonal antibodies against epitopes on such deposits. Encouraging results were obtained from the three investigated antibodies: NEOD001, 11-1F4 and anti-SAP, but further validation is required before these antibodies can be commercialized. In this paper, we review the current active clinical research in AL amyloidosis, which includes the monoclonal antibodies targeting amyloid deposits, daratumumab, Venetoclax, doxycycline, green tea, pomalidomide, carfilzomib and ixazomib. EXPERT OPINION: Monoclonal antibodies, targeting either the amyloid deposits or the plasma cell compartment will likely be integrated into routine treatment practice given their encouraging results and minimal toxicity in the fragile population of AL amyloidosis. Other therapeutic options hold promise to the field as well, but toxicity will likely challenge their routine use. Early recognition remains the best option for outcome enhancement.

A practical review on carfilzomib in multiple myeloma.

Carfilzomib, a second-generation proteasome inhibitor, has been increasingly used in relapsed/refractory multiple myeloma (MM) since its approval by the American food and drug administration (FDA) in the summer of 2012. The drug is active as a single agent and in combination with other antimyeloma agents. As a result of its efficacy and safety in the relapsed/refractory setting, carfilzomib is being evaluated in patients with newly diagnosed MM as well as in high-risk smoldering MM. This review will give a comprehensive summary of the drug, including its mechanism of action, the evaluated doses and schedules as well as a summary of the main clinical trials in the relapsed/refractory and newly diagnosed settings. A focus will be placed upon certain subgroups of interest as well as a description of the toxicity associated with carfilzomib use and a clinical perspective on toxicity management.

Ibrutinib for the treatment of Waldenström macroglobulinemia.

Waldenström macroglobulinemia (WM) is a B-cell non-Hodgkin lymphoma (NHL) characterized by IgM monoclonal gammopathy and bone marrow infiltration by lymphoplasmacytic cells. Until recently, there was no drug specifically approved for WM by the US FDA, leading to wide variations in therapeutic strategies across the globe. Ibrutinib, an oral Bruton tyrosine kinase (BTK) inhibitor, is the first drug approved specifically for WM by the FDA after a clinical trial showed impressive response in previously treated WM. Ibrutinib is a non-stem cell toxic and non-neurotoxic option and suitable for long-term oral maintenance therapy, with the potential of improving survival in WM. With identification of novel genetic mutations impacting response to ibrutinib, it would be possible to individualize therapy based on MYD88 and CXCR4 genotypes. However, long-term safety and efficacy data are required, and cost-effectiveness needs to be addressed before ibrutinib can gain widespread acceptance for front-line therapy of WM.