Comparison of three oral selenium compounds in cancer patients: Evaluation of differential pharmacodynamic effects in normal and malignant cells.

BACKGROUND: Selenium (Se) compounds have demonstrated therapeutic synergism in combination with anticancer treatments whilst reducing normal tissue toxicities in a range of experimental models. While reduction in some toxicities of chemotherapy and radiation has been confirmed in randomised clinical trials, they have not been powered to evaluate improved anticancer efficacy. A lack of data on the clinical potencies of the main nutritionally-relevant forms of Se and the relationship between their pharmacokinetic (PK) profiles and pharmacodynamic (PD) effects in cancer patients has hampered progress to date. The primary objective of this study was to determine the dose and form of Se that can be most safely and effectively used in clinical trials in combination with anti-cancer therapies. STUDY METHODS: In a phase I randomised double-blinded study, the PD profile of sodium selenite (SS), Se-methylselenocysteine (MSC) and seleno-l-methionine (SLM) were compared in two cohorts of 12 patients, one cohort with chronic lymphocytic leukaemia (CLL) and the other with solid malignancies. All 24 patients were randomised to receive 400 µg of elemental Se as either SS, MSC or SLM, taken orally daily for 8 weeks. PD parameters were assessed before, during and 4 weeks after Se compound exposure in plasma and peripheral blood mononuclear cells (PBMCs). RESULTS: No significant sustained changes were observed in plasma concentrations of vascular endothelial growth factor-α (VEGF-α), expression of proteins associated with endoplasmic reticulum stress (the unfolded protein response) or in intracellular total glutathione in PBMCs, in either disease cohort or when grouped by Se compound. CONCLUSIONS: At the 400 µg dose level no substantial changes in PD parameters were noted. Extrapolating from pre-clinical data, the dose examined in this cohort was too low to achieve the Se plasma concentration (≥ 5 µM) expected to elicit significant PD effects. Recruitment of a subsequent cohort at higher doses to exceed this PK threshold is planned.

Comparative Safety and Pharmacokinetic Evaluation of Three Oral Selenium Compounds in Cancer Patients.

Selenium (Se) compounds have demonstrated anticancer properties in both preclinical and clinical studies, with particular promise in combination therapy where the optimal form and dose of selenium has yet to be established. In a phase I randomised double-blinded study, the safety, tolerability and pharmacokinetic (PK) profiles of sodium selenite (SS), Se-methylselenocysteine (MSC) and seleno-l-methionine (SLM) were compared in patients with chronic lymphocytic leukaemia and a cohort of patients with solid malignancies. Twenty-four patients received 400 µg of elemental Se as either SS, MSC or SLM for 8 weeks. None of the Se compounds were associated with any significant toxicities, and the total plasma Se AUC of SLM was markedly raised in comparison to MSC and SS. DNA damage assessment revealed negligible genotoxicity, and some minor reductions in lymphocyte counts were observed. At the dose level used, all three Se compounds are well-tolerated and non-genotoxic. Further analyses of the pharmacodynamic effects of Se on healthy and malignant peripheral blood mononuclear cells will inform the future evaluation of higher doses of these Se compounds. The study is registered under the Australian and New Zealand Clinical Trials Registry No: ACTRN12613000118707.

Sustained pharmacological depletion of serum amyloid P component in patients with systemic amyloidosis.

Serum amyloid P component (SAP) is a universal constituent of amyloid deposits and contributes to their formation and/or persistence. We therefore developed CPHPC ((R)-1-[6-[(R)-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexa-noyl]pyrrolidine-2 carboxylic acid), a novel bis(D-proline) drug, to specifically target SAP and report here a first, exploratory, open label proof of principle study in systemic amyloidosis. CPHPC produced sustained, >95% depletion of circulating SAP in all patients and c. 90% reduction in the SAP content of the two amyloidotic organs that became available. There were no significant adverse effects of either SAP depletion or CPHPC itself. No accumulation of amyloid was demonstrable by SAP scintigraphy in any patient on the drug. In hereditary fibrinogen amyloidosis, which is inexorably progressive, proteinuria was reduced in four of five patients receiving CPHPC and renal survival was prolonged compared to a historical control group. These promising clinical observations merit further study.

AL amyloidosis associated with IgM paraproteinemia: clinical profile and treatment outcome.

AL amyloidosis associated with immunoglobulin M (IgM) paraproteinemia is rare. We report 103 consecutive such patients evaluated at the National Amyloidosis Centre (London, United Kingdom) between 1988 and 2006. Renal, cardiac, and lymph node amyloid was present in 53%, 35%, and 21% of patients, respectively, at presentation and 2 or more organs were involved in 54%. Seventy-three percent had an abnormal bone marrow infiltrate (lymphoid in 87%). The median IgM paraprotein was 8 g/L and serum free light chain (FLC) ratio was abnormal in 77 (88%) of 87. The abnormal FLC component was more than 100 mg/L in only 31% cases. Thirty-two percent achieved a partial hematologic response to treatment with no complete responders, and there appeared to be a greater response to combination regimens than single-agent oral alkylators (59% vs 20%, respectively; P = .003). Four achieved amyloidotic organ responses; organ function remained stable in 68%. None with lymph node involvement showed nodal improvement. Median overall survival was 49 months. AL amyloidosis with IgM paraproteinemia represents a distinctive subset of patients with AL amyloidosis who have a wider variety of underlying clonal disorders (often lymphoid) than AL in general, have low-level FLC abnormality, and should be treated with appropriately tailored chemotherapeutic regimens for the underlying clonal disorder.

Natural history and outcome in systemic AA amyloidosis.

BACKGROUND: Deposition of amyloid fibrils derived from circulating acute-phase reactant serum amyloid A protein (SAA) causes systemic AA amyloidosis, a serious complication of many chronic inflammatory disorders. Little is known about the natural history of AA amyloidosis or its response to treatment. METHODS: We evaluated clinical features, organ function, and survival among 374 patients with AA amyloidosis who were followed for a median of 86 months. The SAA concentration was measured serially, and the amyloid burden was estimated with the use of whole-body serum amyloid P component scintigraphy. Therapy for inflammatory diseases was administered to suppress the production of SAA. RESULTS: Median survival after diagnosis was 133 months; renal dysfunction was the predominant disease manifestation. Mortality, amyloid burden, and renal prognosis all significantly correlated with the SAA concentration during follow-up. The risk of death was 17.7 times as high among patients with SAA concentrations in the highest eighth, or octile, (>or=155 mg per liter) as among those with concentrations in the lowest octile (<4 mg per liter); and the risk of death was four times as high in the next-to-lowest octile (4 to 9 mg per liter). The median SAA concentration during follow-up was 6 mg per liter in patients in whom renal function improved and 28 mg per liter in those in whom it deteriorated (P<0.001). Amyloid deposits regressed in 60% of patients who had a median SAA concentration of less than 10 mg per liter, and survival among these patients was superior to survival among those in whom amyloid deposits did not regress (P=0.04). CONCLUSIONS: The effects of renal dysfunction dominate the course of AA amyloidosis, which is associated with a relatively favorable outcome in patients with SAA concentrations that remain in the low-normal range (<4 mg per liter).

Safety and efficacy of risk-adapted cyclophosphamide, thalidomide, and dexamethasone in systemic AL amyloidosis.

High-dose melphalan with stem-cell transplantation is believed to be the most effective treatment for systemic light-chain (AL) amyloidosis, but many patients are ineligible because of the extent of their disease, and treatment-related mortality (TRM) remains substantial. We report the use of a risk-adapted oral regimen of cyclophosphamide, thalidomide, and dexamethasone (CTD) or attenuated CTD (CTDa) in 75 patients with advanced AL amyloidosis, including 44 patients with clonal relapse after prior therapy. Fifty-one (68%) patients received CTD and 24 (32%) received CTDa. A hematologic response occurred in 48 (74%) of 65 evaluable patients, including complete responses in 14 (21%) and partial responses in 34 (53%) cases. Median estimated overall survival (OS) from commencement of treatment was 41 months, and from diagnosis median was not reached with a median follow-up of 22 months. Three-year estimated OS was 100% and 82% among complete and partial hematologic responders, respectively. Toxicity necessitating cessation of therapy occurred in 8% and was at least grade 2 in 52% of patients. TRM was 4%. The clonal response rates to CTD reported here are higher than any previously reported nontransplantation regimen in AL amyloidosis, and risk adaptation allows its use in poorer risk patients. CTD merits prospective randomized study.

Outcome of autologous stem cell transplantation for AL amyloidosis in the UK.

High-dose chemotherapy with autologous stem cell transplantation (SCT) is widely used as a treatment for systemic AL amyloidosis, but its efficacy has not been proved and it has substantial toxicity in this setting. We report here the outcome of 92 patients evaluated at the UK National Amyloidosis Centre who underwent SCT for AL amyloidosis between 1994 and 2004 in various British centres. Median age was 53 years and median of two organs were affected by amyloidosis. All-cause day 100 mortality [treatment-related mortality (TRM)] was 23% for the entire cohort, although this was substantially greater for patients treated from 1994 to 1998 (15/47, 32%) than subsequently (6/45, 13%). Independent factors significantly associated with TRM on multivariate analysis were: number of affected organs, performance status, serum albumin and age. Response of the underlying clonal disease, defined by > or = 50% reduction in the aberrant serum-free light chain concentration, occurred in 83% of evaluable patients. Overall median survival was 5.3 years, and was 8.5 years among patients who survived beyond day 100. Despite recent refinements in patient selection, TRM remains substantial during SCT for systemic AL amyloidosis, and its place in the therapeutic armamentarium for this disease needs to be defined in randomised controlled clinical studies.

AA amyloidosis complicating hyperimmunoglobulinemia D with periodic fever syndrome: a report of two cases.

AA amyloidosis is the most serious potential complication of the inherited autoinflammatory syndromes and frequently results in end-stage renal failure. Although this complication is well recognized in familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome, and Muckle-Wells syndrome, there is only 1 previous published report of its occurrence in hyperimmunoglobulinemia D with periodic fever syndrome (HIDS). We report 2 further cases of patients with AA amyloidosis in HIDS, both of whom developed dialysis-dependent renal failure, and we describe the outcome of the first renal transplant in this setting.

Implantation of a cardioverter-defibrillator in a patient with cardiac amyloidosis.

BACKGROUND: A 49-year-old woman presented with chest pain of 10 days' duration. Initial physical examinations and laboratory investigations were normal. The patient received symptomatic treatment with beta-blockers, which continued following normal findings on coronary angiogram. About 7 months later the patient developed ventricular arrhythmias, with clinical evidence of left ventricular heart failure. Her arrhythmia symptoms persisted despite pharmacological therapy with atenolol, carvedilol and amiodarone. INVESTIGATIONS: Physical examination, electrocardiography, laboratory testing, serologic testing, exercise-tolerance testing, coronary angiography, chest radiography, cardiac MRI, tongue biopsy, bone-marrow biopsy, CT scan, iodine-123-labeled serum-amyloid-P-component scintigraphy. DIAGNOSIS: Systemic primary amyloidosis (AL amyloidosis), with predominant cardiac involvement. MANAGEMENT: Pharmacological antiarrhythmic therapy and cardioverter-defibrillator implantation. Chemotherapy was planned but, despite intervention, the patient died before this treatment could begin.

Sequential heart and autologous stem cell transplantation for systemic AL amyloidosis.

Extensive cardiac amyloid deposition in systemic AL amyloidosis is associated with a grave prognosis. Heart transplantation is rarely performed because of the systemic and progressive nature of the disease. Patients with severe cardiac amyloid infiltration are ineligible for the preferred treatment of melphalan chemotherapy with stem cell transplantation (SCT) rescue because of the high risk for treatment-related mortality. Heart transplantation followed by SCT was performed in 5 patients with AL amyloidosis and predominant cardiomyopathy. Patients were followed up for a median of 95 months (range, 37-118 months) from diagnosis. At censor, 3 of 5 patients were well without evidence of intracardiac or extracardiac amyloid accumulation, and median overall survival by Kaplan-Meier estimate was not reached. Two patients died of progressive amyloidosis 33 and 90 months after heart transplantation after relapse of their underlying plasma cell dyscrasia. Heart transplantation followed by SCT is feasible in selected patients with cardiac AL amyloidosis and may confer substantial survival benefit.