- Nine out of 10 U.S. physicians polled in a recently released survey said they would consider switching a patient from an originator biologic to a biosimilar, although uncertainty over several key aspects of the approval process suggest a degree of unfamiliarity with the copycat biologics.
- Created by the pharma-backed Biosimilars Forum, the survey asked questions of 1,201 doctors in the U.S. who actively prescribed biologic drugs on their perception of biosimilars. While the survey was released this week, the doctors were polled between November 20, 2015 and January 4, 2016.
- Four biosimilars are currently approved in the U.S., although only Novartis' Zarxio (filgrastim-sndz) has been sold on the market. Biosimilars promise to reduce prescription drug costs for some of the best-selling biologic drugs, such as J&J's Remicade (infliximab) and Amgen's Enbrel (etanercept).
While 91% of polled physicians indicated their willingness to prescribe biosimilars, there was a fair degree of uncertainty regarding the safety and efficacy of biosimilars.
Only 45% of doctors agreed that biosimilars would be "safe and appropriate for use in naive and existing patients," suggesting some discomfort with biosimilars or a lack of awareness over the approval standards of the Food and Drug Administration.
In order to win approval, a biosimilar has to not only be highly similar to its reference product but also demonstrate no clinically meaningful differences in safety or effectiveness.
Generally, physicians were not knowledgeable about several key concepts involved in the regulatory process for biosimilars. Unlike innovator drugs, biosimilars are assessed based on analytical data designed to answer whether a biosimilar is highly similar to its reference product.
Based on the totality of evidence, the FDA can extrapolate from evidence data comparing a biosimilar to its reference product and approve a biosimilar for use in all indications for which the original biologic drug is approved.
Yet only 12% of respondents were comfortable with the idea of extrapolation, the survey showed.
While most physicians surveyed understood the meaning of "interchangeable," a third thought FDA approval meant a biosimilar could be swapped for a biologic by a pharmacist. All four biosimilars approved to date have been approved only as a biosimilar, not as an interchangeable, meaning pharmacists cannot switch prescriptions.
The Biosimilars Forum did note one limitation which could undermine some of the survey's findings. At the time physicians were polled, only Novartis' Zarxio was approved. Doctors may be more knowledgeable now that three other drugs have joined Zarxio.
A number of large pharmas and biosimilars drugmakers, including Amgen, Novartis, Pfizer and Samsung Bioepis, make up the BioSimilars Forum. The group intends to conduct the survey two to three years from now to get a sense of how perceptions have changed over time.