Continuous erythropoietin receptor activator (C.E.R.A.) is a modified recombinant human erythropoietin which has been designed inhibitor bulk to have a longer half-life than other ESA preparations [32]. As a result, correction of anemia can be achieved with dosing every two weeks in hemodialysis patients and once a month in nondialysis CKD patients, while during the maintenance phase, all patients require only once-monthly dosing [33], offering greater convenience for patients and healthcare staff. The current multicenter, prospective, observational study was designed to evaluate the efficacy and safety of C.E.R.A. in anemic kidney transplant recipients, either administered de novo or following conversion from more frequently administered ESA therapies. The study design was developed with several points in mind.

First, results from the CHOIR [23] and CREATE [24] studies raised doubts about Hb targets in patients with CKD, leading to revised recommendations [33]. However, Hb levels in routine practice are largely undocumented in kidney transplantation. Second, recent Phase III trials of C.E.R.A. targeted an Hb level of not more than 13g/dL [34, 35], but the extent to which this upper threshold is maintained in kidney transplant patients during routine management was unknown. Lastly, interventional studies typically report mean Hb values, and data relating to Hb fluctuation in individual kidney transplant patients are lacking. 2. Methods 2.1. Study Design and Conduct This was a prospective, noninterventional, single-arm study of kidney transplant patients receiving C.E.R.A.

therapy at 37 German transplant centers, which took place during the period from September 2007 to November 2011. The initial observation period of nine months was extended to 15 months, as permitted in the study protocol, in order to gather longer-term data, especially with regard to the phenomenon of Hb cycling. The study was undertaken in accordance with the principles laid down in the Declaration of Helsinki and Good Clinical Practice. The study protocol was approved by the ethics committee at the Medizinische Hochschule Hannover, Hannover, Germany. All participants provided written informed consent. 2.2. Patient Population Patients were eligible for inclusion if they had received a kidney transplant at least three months prior to study entry and had stable graft function (defined as ��25% loss of function in the previous three months) and their physicians had decided to administer C.

E.R.A. therapy prior to study entry. All patients were required to have a life expectancy of at least nine months Carfilzomib (the initial planned duration of the study period), with no active malignant disease or acute infection and no acute blood loss or decrease in Hb level, in the four weeks prior to inclusion. Patients on dialysis were excluded.