The FDA has accepted for review Mylan’s (and Mylan’s biosimilars partner Biocon’s) Biologics License Application (BLA) for the proposed biosimilar to Amgen’s Neulasta (pegfilgrastim), currently called MYL-1401H. The proposed biosimilar to Neulasta is used to reduce the duration of neutropenia and the incidence of fever associated with neutropenia, in adults treated with chemotherapy for certain cancers. The FDA’s goal for a decision on the application, based on the User Fee Act, is October 9, 2017.
Pegfilgrastim is a long-acting version of Amgen’s Neupogen (filgrastim). Biosimilars of Amgen’s filgrastim have been on the European market for years, and Sandoz’s biosimilar of Neupogen (Zarxio) is the first US biosimilar to have been approved and marketed. However, Neulasta is a bigger and more complex biologic than Neupogen, and biosimilar makers have not yet been successful in gaining FDA or European Medicines Agency (EMA) approval for proposed biosimilars to Neulasta.1
The complexity of Neulasta is largely due to the presence of the polyethylene glycol (PEG) molecule, which is bonded to filgrastim. The presence of PEG on filgrastim slows the rate at which the molecule is metabolized and eliminated from the body, which reduces the frequency of dosing. PEG is what makes Neulasta long acting. However, the presence of PEG also makes it more difficult to develop a biosimilar to Neulasta. Other companies have experienced rejections of their applications for Neulasta biosimilars in the United States and in Europe. The FDA rejected Sandoz’s application for its Neulasta biosimilar in July 2016; Sandoz may be submitting additional data to the FDA in support of the application in 2018. The company has also had difficulties in its European submission for a Neulasta biosimilar, and withdrew its application to the EMA for a Neulasta biosimilar. Sandoz will not be able to provide additional data to the EMA within that agency’s permitted time frame.
Other drug makers have faced similar problems gaining approvals of their Neulasta biosimilars, including Gedeon Richter, which withdrew its application to the EMA in 2016, and Apotex, which is still waiting for an FDA advisory committee meeting on its Neulasta biosimilar, although its application was accepted for review in December 2014. Several other Neulasta biosimilars are also being reviewed by the EMA and FDA, and it remains to be seen how the products will fare.