epoetin-alfa and Drug-Hypersensitivity

A "biosimilar" or "similar biological medicinal product" is a biological agent that is similar in terms of quality, safety, and efficacy to an authorized reference biological medicine. Since the expiration of the epoetin alfa patent in Europe, three agents have received marketing authorization from the European Medicines Agency: Binocrit (epoetin alfa; aka Abseamed and Epoetin Alfa Hexal), Retacrit (epoetin zeta; aka Silapo), and Eporatio (epoetin theta; aka Biopoin and Ratioepo).. Using the EMA dossiers and journal publications, this article reviews clinical safety data for these products, with emphasis on serious/severe adverse events and a special consideration of immunogenicity, venous thromboembolism, and mortality.. A review of the available safety evidence shows that all three agents discussed have similar safety profiles. None were statistically higher on safety parameters to what is known about ESA as a class, when stratified by population. As with ESAs in general, immunogenicity, venous thromboembolism, and mortality are all concerns. What is known about ESAs regarding safety can be extended to biosimilar erythropoietins. Since biosimilars are unique, complex biological molecules, safety profiles may evolve from common to differentiated, once long-term product-specific safety data are available. Large-sample, long-term, observational studies of real-world practice will provide the heterogeneity and statistical power to demonstrate product-specific effectiveness and safety profiles. Statistically, out of the commercially available formulations of the three products reviewed, no single product is less or more safe.

Topics: Animals; Biosimilar Pharmaceuticals; Drug Hypersensitivity; Drug Monitoring; Epoetin Alfa; Erythropoietin; Hematinics; Humans; Incidence; Pharmacovigilance; Recombinant Proteins; Venous Thromboembolism

Sensitivity to iron dextran is a potent obstacle to maintaining optimum iron status in patients with dialysis-associated anemia. As part of the North American clinical trials for iron sucrose injection, we examined the effect of intravenous (IV) iron sucrose in 23 hemodialysis patients with documented sensitivity to iron dextran, ongoing epoetin alfa therapy, and below-target-range hemoglobin (Hgb) levels (<11.0 g/dL). We assigned patients to treatment groups according to whether reactions they had experienced to iron dextran were judged to be mild (n = 16; group A) or severe (n = 7; group B). We prospectively examined adverse events and vital signs after administering 100 mg of IV iron sucrose in each of 10 consecutive dialysis treatment sessions and compared results with those recorded in each of three consecutive dialysis sessions without iron treatment. We administered iron sucrose by IV push over 5 minutes to group A patients and by IV push over 5 minutes or IV infusion over 15 to 30 minutes to group B patients. We did not administer a test dose. Results showed no serious adverse drug reactions after a total of 223 doses of iron sucrose (184 doses by IV push, 39 doses by IV infusion). Intradialytic blood pressure changes after IV iron sucrose injection did not differ from those recorded during dialysis sessions without treatment. An increase in values for Hgb, hematocrit, transferrin saturation, and ferritin, coupled with no significant change in epoetin dose and a decrease in total iron-binding capacity, confirmed the efficacy of iron sucrose injection in managing anemia. We conclude that iron sucrose injection is safe and effective in the management of anemia in patients sensitive to iron dextran and can be administered without a test dose by IV push or infusion.

Topics: Anemia, Iron-Deficiency; Blood Pressure; Drug Hypersensitivity; Epoetin Alfa; Erythropoietin; Ferric Compounds; Ferric Oxide, Saccharated; Glucaric Acid; Hematinics; Humans; Infusions, Intravenous; Injections, Intravenous; Iron-Dextran Complex; Middle Aged; Prospective Studies; Recombinant Proteins; Renal Dialysis

Anemia frequently complicates the treatment of chronic hepatitis C with interferon and ribavirin (RVN), requiring dose reduction and jeopardizing sustained virologic response. Increasingly, epoetin alfa is used to prevent anemia in this setting. Below, we report the first case of pure red cell aplasia (PRCA) in a patient with chronic hepatitis C who received epoetin alfa (Procrit) to manage anti-viral treatment-induced anemia. Red blood cell transfusion-dependence developed 16 wk after the patient was started on peginterferon alfa-2b and RVN for chronic hepatitis C despite the simultaneous administration of epoetin alfa and subsequent discontinuation of the antiviral medications. Bone marrow biopsy was consistent with PRCA. High-titer erythropoietin antibodies, assayed by two methods, appeared shortly after epoetin alfa was administered, and were associated with a decline in serum erythropoietin to undetectable levels. Erythropoietin antibodies directed toward epoetin alfa were shown to cross react with darbepoetin alfa (Aranesp), and a neutralization assay confirmed that they inhibited cell growth in the presence of erythropoietin. Transfusion-dependence resolved approximately 16 wk after discontinuing epoetin alfa, and 6 wk after starting danazol. PRCA caused by the development of erythropoietin antibodies is a potentially life-threatening complication of administering epoetin alfa to prevent the anemia associated with antiviral therapy in patients with chronic hepatitis C.

Topics: Antibodies; Danazol; Drug Hypersensitivity; Epoetin Alfa; Erythropoietin; Estrogen Antagonists; Follow-Up Studies; Hematinics; Hepatitis C, Chronic; Humans; Male; Middle Aged; Radioimmunoprecipitation Assay; Recombinant Proteins; Red-Cell Aplasia, Pure

Topics: Drug Hypersensitivity; Eosinophilia; Epoetin Alfa; Erythema Multiforme; Erythropoietin; Exanthema; Fever; Hematinics; Humans; Male; Middle Aged; Recombinant Proteins; Syndrome