© Sandoz Inc. 2015
The leukocyte growth factor Zarxio (filgrastim-sndz), the first biosimilar product to gain approval from the US Food and Drug Administration (FDA), is now available in the US.
Zarxio was approved by the FDA on March 6. The product, made by Sandoz, Inc., is biosimilar to Amgen Inc.’s Neupogen, which was originally licensed in 1991.
Zarxio is marketed as Zarzio outside the US. The biosimilar is available in more than 60 countries worldwide.
In the US, Zarxio is approved for the same indications as Neupogen. So Zarxio can be prescribed for the following 5 indications.
Patients with cancer receiving myelosuppressive chemotherapy: to decrease the incidence of infection, as manifested by febrile neutropenia, in patients with nonmyeloid malignancies receiving myelosuppressive anticancer drugs associated with a significant incidence of severe neutropenia with fever.
Patients with acute myeloid leukemia receiving induction or consolidation chemotherapy: to reduce the time to neutrophil recovery and the duration of fever, following induction or consolidation chemotherapy.
Patients with cancer undergoing bone marrow transplant: to reduce the duration of neutropenia and neutropenia-related clinical sequelae—eg, febrile neutropenia—in patients with nonmyeloid malignancies undergoing myeloablative chemotherapy followed by bone marrow transplant.
Patients undergoing autologous peripheral blood progenitor cell collection and therapy: for the mobilization of autologous hematopoietic progenitor cells into the peripheral blood for collection by leukapheresis.
Patients with severe chronic neutropenia: for chronic administration to reduce the incidence and duration of sequelae of neutropenia—eg, fever, infections, oropharyngeal ulcers—in symptomatic patients with congenital neutropenia, cyclic neutropenia, or idiopathic neutropenia.
PIONEER trial
The FDA’s approval of Zarxio was based on data showing that Zarxio is highly similar to Neupogen, with no clinically meaningful differences between the products.
The head-to-head PIONEER study was the final piece of evidence the FDA used to approve Zarxio as biosimilar to Neupogen. Results of the trial were presented at ASH 2014.
Zarxio and Neupogen both produced the expected reduction in the duration of severe neutropenia in breast cancer patients undergoing myelosuppressive chemotherapy—1.17 ± 1.11 and 1.20 ±1.02 days, respectively.
The mean time to absolute neutrophil count recovery in cycle 1 was also similar—1.8 ± 0.97 days in the Zarxio arm and 1.7 ± 0.81 days in the Neupogen arm. No immunogenicity or antibodies against rhG-CSF were detected throughout the study.
The researchers said there were no obvious differences between Zarxio and Neupogen with regard to treatment-emergent adverse events.
The most common side effects observed with Zarxio are aching bones/muscles and redness, swelling, or itching at the injection site. Serious side effects may include spleen rupture; serious allergic reactions that may cause rash, shortness of breath, wheezing and/or swelling around the mouth and eyes; fast pulse and sweating; and acute respiratory distress syndrome.
For more details on Zarxio, see the full prescribing information or visit www.zarxio.com.
