Helena Isoniemi

A blinded, randomized clinical trial of mycophenolate mofetil for the prevention of acute rejection in cadaveric renal transplantation

Mycopehenolate mofetil (MMF) is a powerful immunosuppressant that inhibits the proliferation of T and B lymphocytes by blocking the enzyme inosine monophosphate dehydrogenase. MMF has been shown to prevent acute graft rejection in animal experiments and may have an important role in clinical renal transplantation. We conducted a prospective, double-blind, multi-center trial to compare the efficacy and safety of MMF and azathioprine within standard immunosuppressive regimen for patients receiving a first or second cadaveric renal graft. A total of 503 patients were randomized to groups receiving MMF 3 g (n=164), MMF 2 g (n=173), or azathioprine (AZA) 100-150 mg (n=166) daily. All were treated simultaneously with equivalent doses of cyclosporine and oral corticosteroids and followed for 12 months. The primary endpoint was treatment failure, defined as the occurrence of biopsy-proven graft rejection, graft loss, patient death, or discontinuation of the study drug during the first 6 months after transplantation. Treatment failure occurred in 50.% of patients in the AZA group by 6 months after transplantation, compared with 34.8% in the MMF 3g group (P=0.0045) and 38.2 % in the MMF 2g group (P=0.0287). Biopsy-proven rejection occurred in 15.9% of patients in the MMF 3 g group and 19.7% in the MMF2 g group, compared with 35.5% in the AZA group. Rejection of histologic severity grade II or more developed in 6.1 %, 10.4% and 19.9% of patients in the MMF 3 g, MMF 2 g, and AZA groups, respectively. Patients receiving MMF required less frequent and less intensive treatment for acute rejection: 24.4% of patients on MMF 3 g and 31.0% on MMF 2 g were tested for acute rejection, compared with 47.5% on AZA. Only 4.9% on MMF 3 g and 8.8% on MMF 2 g required antilymphocyte antibodies for treatment of severe or steroid-resistant rejection, compared with 15.4% of the patients on AZA. At 1 year after transplantation, graft survival in the MMF groups was marginally superior to that in the AZA group, although this difference was not statistically significant. Gastrointestinal toxicity and tissue-invasive cytomegalovirus infection were more common in the MMF 3 g group. Noncutaneous malignancies occurred in six patients on MMF 3 g, three patients on MMF 2 g, and four patients on AZA. Lymphoproliferative disorders occurred in two patients per MMF group, compared with one patient receiving AZA. MMF appears to be an important advance in prophylaxis following renal transplantation. It is associated with a significantly lower rate of treatment failure compared with AZA during the first 6 months after renal transplantation and produces a clinically important reduction in the incidence, severity, and treatment of acute graft rejection. These differences persist throughout the first year of follow-up. Clinical benefit was greatest with a dose of MMF 3 g/day, but gastrointestinal effects, invasive cytomegalovirus infection, and malignancies were slightly more common at that dose. The appropriate dose may lie between 2 g and 3 g per day and may require individualization depending on clinical course or other factors.

Blocking VEGFR-3 suppresses angiogenic sprouting and vascular network formation

Angiogenesis, the growth of new blood vessels from pre-existing vasculature, is a key process in several pathological conditions, including tumour growth and age-related macular degeneration. Vascular endothelial growth factors (VEGFs) stimulate angiogenesis and lymphangiogenesis by activating VEGF receptor (VEGFR) tyrosine kinases in endothelial cells. VEGFR-3 (also known as FLT-4) is present in all endothelia during development, and in the adult it becomes restricted to the lymphatic endothelium. However, VEGFR-3 is upregulated in the microvasculature of tumours and wounds. Here we demonstrate that VEGFR-3 is highly expressed in angiogenic sprouts, and genetic targeting of VEGFR-3 or blocking of VEGFR-3 signalling with monoclonal antibodies results in decreased sprouting, vascular density, vessel branching and endothelial cell proliferation in mouse angiogenesis models. Stimulation of VEGFR-3 augmented VEGF-induced angiogenesis and sustained angiogenesis even in the presence of VEGFR-2 (also known as KDR or FLK-1) inhibitors, whereas antibodies against VEGFR-3 and VEGFR-2 in combination resulted in additive inhibition of angiogenesis and tumour growth. Furthermore, genetic or pharmacological disruption of the Notch signalling pathway led to widespread endothelial VEGFR-3 expression and excessive sprouting, which was inhibited by blocking VEGFR-3 signals. Our results implicate VEGFR-3 as a regulator of vascular network formation. Targeting VEGFR-3 may provide additional efficacy for anti-angiogenic therapies, especially towards vessels that are resistant to VEGF or VEGFR-2 inhibitors.

Chronic Allograft Rejection

The short-term results of organ transplantation have significantly improved during the past few years. However, long-term success has remained on the same level as in the pre-cyclosporine era, with the half-life of a renal transplant being 7 years or more (Cho & Terasaki 1988). Although chronic rejection may not be the sole reason for transplants being lost during subsequent years, there is good recent evidence indicating that it is a leading cause in late graft failure (Kirkman et al. 1982, Mahony & Sheil 1987, Dennis et al. 1989). There are several recent publications (Paul & Solez 1991, Paul & Fellstrom 1992, Foegh 1990, Tilney et al. 1991, Adams & Tilney 1989, Fellstrom et al. 1989a) that give good overviews on different clinical and biological parameters of chronic allograft rejection. In this communication we will primarily concentrate on our own experience.

Histological chronic allograft damage index accurately predicts chronic renal allograft rejection.

Chronic rejection has emerged as a major problem in renal transplantation, and clinical trials for prophylaxis and therapy are underway. Use of graft and patient survival as endpoints in prophylactic studies requires long follow-ups to read the endpoint. There is also an obvious need for a starting point for intervention studies. Previously, we formed a histological chronic allograft damage index (CADI), based on numerical scoring of histological alterations compatible with chronic rejection. Using protocol core needle biopsies of 89 functioning grafts 2 years after transplantation and a follow-up of 6 years, we demonstrate now that (a) the CADI at 2 years correlates significantly (r=0.717, P=0.0001) with transplant function at 6 years, and (b) that the CADI at 2 years reliably (P=0.001) predicts the patients who will proceed to clinical chronic rejection later. As protocol core biopsy is an early predictive parameter for chronic rejection, our results suggest that a protocol core biopsy (at 2 years or possibly even earlier) should be included in all clinical investigative protocols dealing with chronic renal allograft rejection.

Safety and efficacy of a single bolus administration of recombinant factor VIIa in liver transplantation due to chronic liver disease

Orthotopic liver transplantation (OLT) can be associated with excessive blood loss. As a result, there may be increased risk of adverse outcomes. Activated recombinant factor VII (rFVIIa) has demonstrated the ability to improve hemostasis in a variety of disorders; however, there has been a limited amount of research into its use in OLT. The purpose of this dose‐finding study was to examine the efficacy and safety of rFVIIa in the reduction of bleeding in patients undergoing OLT. In this double‐blind trial, patients with end‐stage liver disease scheduled for OLT were randomized to 1 of 4 parallel study groups. They received a single intravenous bolus of rFVIIa (20, 40, or 80 μg/kg) or placebo prior to surgery. The primary assessment endpoint was the total number of red blood cell (RBC) units transfused perioperatively. Safety was evaluated by adverse events reported. Eighty‐three comparable patients were randomized to receive study product, with 82 ultimately undergoing OLT. There were no significant differences in required RBC units between the placebo and rFVIIa study groups. The number of adverse events was comparable between study groups. In conclusion, rFVIIa has a good safety profile in patients undergoing OLT. However, the doses studied did not have any effect on the number of RBC transfusions required. (Liver Transpl 2005;11:895–900.)

A randomized multicenter trial of the anti-ICAM-1 monoclonal antibody (enlimomab) for the prevention of acute rejection and delayed onset of graft function in cadaveric renal transplantation: a report of the European Anti-ICAM-1 Renal Transplant Study Group.

BACKGROUND T-cell activation through T-cell receptor engagement requires co-stimulatory molecules and also adhesion molecules such as ICAM-1. Moreover ICAM-1 mediates leukocyte invasion from the blood into tissue during inflammatory processes. In animal studies using mouse monoclonal antibodies against ICAM-1 (enlimomab), renal allograft survival has been improved and reperfusion damage from ischemia reduced. The European Anti-ICAM-1 Renal Transplant Study (EARTS) was a randomized, double-blind, parallel-group, placebo-controlled study lastingl year and performed in 10 transplant centers in Europe. METHODS A total of 262 recipients of cadaveric kidneys were given either enlimomab or a placebo for 6 days and were given triple immunosuppressive therapy of cyclosporine, azathioprine, and prednisolone. The primary efficacy endpoint was the incidence of the first acute rejection within 3 months, and each event was assessed by a committee including investigators and independent pathologists. RESULTS There was no significant difference in the incidences of first acute rejection at 3 months between the placebo and enlimomab groups (39% vs. 45%), and enlimomab did not reduce the risk of delayed onset of graft function (DGF) (26% vs. 31%). Neither was there a difference in patient survival (95% vs. 91%) or graft survival (89% vs. 84%) at 1 year. Fatal events occurred in 19 (7%) patients (7 placebo, 12 enlimomab). Clinically, the most important non-fatal adverse events were infections; however, there was no statistically significant difference between the incidences in the two groups (70% vs. 79%). CONCLUSION Short term enlimomab induction therapy after renal transplantation did not reduce the rate of acute rejection or DGF.

Risk of Malignant Neoplasms After Liver Transplantation: A Population-Based Study

Posttransplant malignancies have become a serious long‐term complication after liver transplantation. Our aim was to compare the incidence of posttransplant cancers with national cancer incidence rates. The study included all Finnish liver transplant patients transplanted at the Helsinki University Central Hospital between 1982 and 2005. The cohort was linked with the nationwide Finnish Cancer Registry. Observed numbers of cancers were compared to site‐specific expected numbers based on national cancer incidence rates stratified by age, sex, and calendar time. The standardized incidence ratios (SIRs) were calculated as observed‐to‐expected ratios. Thirty‐nine posttransplant de novo cancers and 11 basal cell carcinomas were found in the cohort of 540 patients during 3222 person years of follow‐up. The overall SIR was 2.59 (95% confidence interval 1.84‐3.53). SIR was higher for males (SIR 4.16) than for females (SIR 1.74), higher among children (SIR 18.1) than among adults (SIR 5.77 for ages of 17‐39 years and 2.27 for ages ≥ 40 years), and more elevated in the immediate posttransplant period (SIR 3.71 at < 2 years) compared to later periods (SIR 2.46 at 2‐10 years and 1.53 at >10 years). The most common cancer types were nonmelanoma skin cancer (SIR 38.5) and non‐Hodgkin lymphoma (SIR 13.9). Non‐Hodgkin lymphoma was associated with male gender, young age, and the immediate posttransplant period, whereas old age and antibody induction therapy increased skin cancer risk. In conclusion, cancer incidence is increased among liver transplant patients compared to the general population. This study points out the importance of cancer surveillance after liver transplantation. Liver Transpl 14:1428–1436, 2008.

High-volume plasma exchange in patients with acute liver failure: An open randomised controlled trial.

BACKGROUND & AIMS Acute liver failure (ALF) often results in cardiovascular instability, renal failure, brain oedema and death either due to irreversible shock, cerebral herniation or development of multiple organ failure. High-volume plasma exchange (HVP), defined as exchange of 8-12 or 15% of ideal body weight with fresh frozen plasma in case series improves systemic, cerebral and splanchnic parameters. METHODS In this prospective, randomised, controlled, multicentre trial we randomly assigned 182 patients with ALF to receive either standard medical therapy (SMT; 90 patients) or SMT plus HVP for three days (92 patients). The baseline characteristics of the groups were similar. The primary endpoint was liver transplantation-free survival during hospital stay. Secondary-endpoints included survival after liver transplantation with or without HVP with intention-to-treat analysis. A proof-of-principle study evaluating the effect of HVP on the immune cell function was also undertaken. RESULTS For the entire patient population, overall hospital survival was 58.7% for patients treated with HVP vs. 47.8% for the control group (hazard ratio (HR), with stratification for liver transplantation: 0.56; 95% confidence interval (CI), 0.36-0.86; p=0.0083). HVP prior to transplantation did not improve survival compared with patients who received SMT alone (CI 0.37 to 3.98; p=0.75). The incidence of severe adverse events was similar in the two groups. Systemic inflammatory response syndrome (SIRS) and sequential organ failure assessment (SOFA) scores fell in the treated group compared to control group, over the study period (p<0.001). CONCLUSIONS Treatment with HVP improves outcome in patients with ALF by increasing liver transplant-free survival. This is attributable to attenuation of innate immune activation and amelioration of multi-organ dysfunction.

Hypertension and overall survival in metastatic colorectal cancer patients treated with bevacizumab-containing chemotherapy

Background:Hypertension (HTN) is a common toxicity of anti-VEGF (vascular endothelial growth factor) antibody treatment. It may be a marker of VEGF signalling pathway inhibition and therefore represent a cancer biomarker in metastatic colorectal cancer (mCRC) patients treated with chemotherapy and bevacizumab.Methods:A total of 101 consecutive patients with mCRC were treated with standard chemotherapy combined with bevacizumab at dose of 2.5 mg kg−1 per week in a single centre. The median follow-up time of the patients alive was 64 months. Blood pressure was measured before each bevacizumab infusion, and HTN was graded according to common toxicity criteria for adverse events version 3.0.Results:Overall, 57 patients (56%) developed ⩾grade 1 HTN (median blood pressure 168/97 mm Hg), whereas 44 (44%) remained normotensive when treated with bevacizumab-containing chemotherapy regimen. Overall response rate was higher among patients with HTN (30 vs 20%; P=0.025). Hypertension was associated with improved progression-free survival (10.5 vs 5.3 months; P=0.008) and overall survival (25.8 vs 11.7 months; P<0.001), and development of HTN within 3 months had an independent, prognostic influence in a multivariate landmark survival analysis together with other known mCRC prognostic factors (P=0.007). There was no association between HTN and development of thromboembolic complications.Conclusion:Hypertension may predict outcome of bevacizumab-containing chemotherapy in mCRC. These data require confirmation in prospective studies including pharmacodynamic and pharmacokinetic analyses.

Health-Related Quality of Life and Employment Status of Liver Transplant Patients

Health‐related quality of life (HRQoL) is one preferable outcome measure of medical interventions such as liver transplantation (LT). The aim of this study was to compare HRQoL of LT patients with that of the general population and to assess the employment status of LT patients. HRQoL was measured with the 15D instrument, a validated, non–disease‐specific, 15‐dimensional, self‐administered HRQoL instrument. The questionnaire was sent to all adult LT patients in Finland (401 patients) alive in June 2007. The response rate was 89% (353 patients). The results were compared to those of 6050 age‐standardized and gender‐standardized controls from the general population. LT patients (mean age, 55 years; range, 20‐82) had slightly worse HRQoL scores than the general population (mean 15D score, 0.889 versus 0.907; P < 0.002). Survival time and retransplantation did not affect HRQoL significantly in age‐adjusted and gender‐adjusted analyses. HRQoL decreased with increasing age (P < 0.0001). Patients transplanted for acute liver failure (ALF) or chronic liver disease (CLD) had significantly worse HRQoL than the general population (P = 0.014 and P = 0.040). Forty‐four percent of working‐age patients were employed at the time of the study. Persons that were employed had significantly better HRQoL than those unemployed (15D scores, 0.934 versus 0.859; P < 0.0001). Eighty‐seven percent of patients experienced improved working capacity after LT. Early retirement was the most common cause of unemployment (56% of unemployed patients), and those patients presented with worse HRQoL than patients unemployed for other reasons. In conclusion, HRQoL of LT patients is very close to that of the general population. Older age, CLD, and ALF impair HRQoL. Employment is an indicator of HRQoL. Liver Transpl 15:64–72, 2009.