For a second straight day, the US Food and Drug Administration’s (FDA) Arthritis Advisory Committee unanimously pushed for the approval of a new biosimilar, this time for Sandoz’s biosimilar for Amgen’s blockbuster Enbrel (etanercept).
Wednesday’s vote – 20-0, with no abstentions – comes on the heels of Tuesday’s 26-0 vote in favor of approving Amgen’s biosimilar for AbbVie’s blockbuster Humira (adalimumab).
The discussion of Sandoz’s biosimilar was also less focused (than Tuesday's discussion) on the basics of what biosimilarity means and how FDA approves these new products. Wednesday's discussion focused more on extrapolation and postmarket surveillance to ensure that the biosimilar is effective in all of the indications it is likely to be approved for.
Jennifer Horonjeff, PhD, a consumer representative on the panel and a research fellow at the Center for Immune Disease with Onset in Childhood, Division of Rheumatology, Department of Medicine at Columbia University in New York, said Wednesday’s decision was “much easier” than Tuesday’s because of FDA’s explanation that the extrapolation is between products and not between indications.
And like at Tuesday’s meeting, the idea of “non-medical switching” was also raised. David Solomon, MD, PhD, professor of medicine at Harvard Medical School, said non-medical switching “is a major concern” and FDA needs to offer more clarification. FDA’s spokesman did not offer an immediate response when questioned.
A couple of other panelists also raised concerns about the idea of insurers forcing a switch from reference biologic to biosimilar without the consent of patients and doctors because of cost savings.
Solomon added that he thinks postmarket surveillance of biosimilars will be key in understanding the validity of the extrapolation.
The unanimously positive panel vote on Wednesday (FDA does not have to follow the advice of its outside panels but usually does) follows FDA staff’s positive take on Sandoz’s application, noting: “In considering the totality of the evidence submitted, the data submitted by the Applicant [Sandoz] show that GP2015 is highly similar to US-licensed Enbrel, notwithstanding minor differences in clinically inactive components, and that there are no clinically meaningful differences between GP2015 and US-licensed Enbrel in terms of the safety, purity, and potency of the product.”