Affymax, Inc. (Nasdaq:AFFY) and Takeda Pharmaceuticals U.S.A., Inc. (TPUSA) today announced the presentation of post-hoc sub-group analyses of the EMERALD Phase 3 studies that evaluated OMONTYS® (peginesatide) Injection, an erythropoiesis-stimulating agent (ESA), for the treatment of anemia due to chronic kidney disease (CKD) in adult dialysis patients. The analyses, which explore intravenous (IV) iron utilization in U.S. patients in the EMERALD Phase 3 studies, were presented in an oral session at the 2012 American Society of Nephrology (ASN) Kidney Week meeting.
In these exploratory post-hoc analyses, investigators pooled data on IV iron dose, along with measures of iron deficiency -- serum ferritin and transferrin saturation (TSAT), from U.S. patients enrolled in the EMERALD 1 and 2 studies (approximately 80 percent of study population).
In the full analysis population (randomized patients receiving ≥1 study drug dose; n=853 OMONTYS, n=436 epoetin) over a 60-week period, patients in the OMONTYS group received an average of 148.8 mg of IV iron per month and patients in the epoetin group received 168.5 mg per month. In the completer population (≥60 weeks’ drug exposure; ferritin, TSAT measured at same visit; n=604 OMONTYS; n=336 epoetin), patients in the OMONTYS group received an average of 152.9 mg per month and patients in the epoetin group received an average of 171.8 mg per month. TSAT at baseline was 30.2% and 29.4% in the OMONTYS and epoetin groups, respectively. Beginning at the first time point (week 12), TSAT for the full analysis population was 37.9% and 30.7% for OMONTYS and epoetin, respectively, and TSAT for the completer analysis population was 37.9% and 30.9% for OMONTYS and epoetin, respectively. Serum ferritin levels at baseline were 686 ng/mL and 674 ng/mL in the OMONTYS and epoetin groups, respectively. At week 60, serum ferritin levels for the full analysis population were 742 ng/mL and 768 ng/mL in the OMONTYS and epoetin groups, respectively, and serum ferritin levels for the completer analysis population were 733 ng/mL and 752 ng/mL in the OMONTYS and epoetin groups, respectively. The clinical significance of these analyses is unknown.
"Anemia management is multi-faceted and given the interdependence of irons and ESAs in red blood cell production, it's important to evaluate utilization of these agents in dialysis patients who are being treated for the condition," said Robert Provenzano, MD, Chair, Division of Nephrology, St. John Hospital & Medical Center, Detroit, and presenter of these EMERALD analyses. "The observations of these post-hoc analyses from the EMERALD studies may warrant further scientific evaluation."
According to the OMONTYS prescribing information, healthcare professionals should correct or exclude other causes of anemia, including iron deficiency, before initiating treatment. The majority of patients with CKD will require supplemental iron during the course of ESA therapy. Evaluate transferrin saturation and serum ferritin prior to and during treatment, and administer supplemental iron when serum ferritin is less than 100 mcg/L or when serum ferritin saturation is less than 20%. For lack or loss of response to OMONTYS, initiate a search for causative factors, including iron deficiency.