Extension Study to Evaluate Safety and Tolerability of Peginesatide for Long-Term Treatment of Anemia in Participants With CKD

The purpose of this study was to evaluate the long term safety and tolerability of peginesatide for the maintenance of hemoglobin in participants with chronic kidney disease (CKD) who had received at least 24 weeks of peginesatide treatment in an earlier study.

Anemia associated with chronic kidney disease is due to several factors, primarily the inability of the diseased kidneys to produce adequate amounts of endogenous erythropoietin. Ancillary factors include the shortened lifespan of red blood cells, iron and other nutritional deficiencies, infection, and inflammation. The presence and severity of anemia are related to the duration and extent of kidney failure. Anemia is associated with increased mortality, increased likelihood of hospitalization, reduced cognitive function, and increased left ventricular hypertrophy and heart failure.

Erythropoiesis stimulating agents have been established as a treatment for anemia in subjects with chronic kidney disease, and have improved the management of anemia over alternatives such as transfusion. Peginesatide is a parenteral formulation developed for the treatment of anemia associated with chronic kidney disease. Peginesatide binds to and activates the human erythropoietin receptor, and stimulates erythropoiesis in human red cell precursors in a manner similar to other known erythropoiesis-stimulating agents (ESAs).

Study participants had received at least 24 weeks of peginesatide dosing in a previous Affymax-sponsored study (NCT00228449) and were to receive doses of peginesatide for approximately 54 months. However, the Sponsor ended the study early.

Eligibility Criteria:
Inclusion Criteria:

* Participant is informed of the investigational nature of this study and has given written, witnessed informed consent in accordance with institutional, local, and national guidelines
* Males or females ≥ 18 years of age. Pre-menopausal females (with the exception of those who are surgically sterile) must have a negative pregnancy test at screening; those who are sexually active must practice a highly effective method of birth control for at least 4 weeks prior to study drug administration, and must be willing to continue contraception until at least 4 weeks after the last dose of study drug.
* Participant who has received at least 24 weeks of peginesatide dosing in a previous Affymax-sponsored study
* One hemoglobin value of \> 10.0 g/dL in the 4 weeks prior to study drug administration

Exclusion Criteria:

* Known intolerance to peginesatide or pegylated products
* History of antibodies to any erythropoiesis stimulating agent (ESA) or history of pure red cell aplasia (PRCA)
* High likelihood of early withdrawal or interruption of the study (e.g., participant suffers from any clinically significant medical disease or condition that may, in the Investigator's opinion, interfere with safety, assessment, or follow-up of the participant)
* Anticipated life expectancy \< 18 months
* Receipt of any ESA other than peginesatide at any time after participant enrollment in the previous Affymax-sponsored study