PhRMA has spoken out against FDA plans to allow biosimilar manufacturers flexibility in delivery device and formulation choice.
Since the US Food and Drug Administration (FDA) outlined its plans in biosimilar draft guidance several firms have criticised its thinking. Now the collective might of the US drug industry, the Pharmaceutical Research and Manufacturers of America (PhRMA), has joined the debate.
“Intentionally introducing differences to the molecule or the finished product will increase the level of uncertainty regarding the proposed biosimilar’s similarity to the reference product”, Jeffrey Francer, assistant general counsel at PhRMA, wrote in feedback to the FDA.
Francer and his co-authors fear that giving biosimilar manufacturers choice adds to the “risk of unintended or unanticipated clinically meaningful differences”. As well as raising health risks the authors claim the flexibility goes against the law which led to creation of the biosimilar pathway.
“The statute imposes a scientifically rigorous standard that each product must be highly similar to its reference product. Statutory considerations therefore counsel that FDA guidance should recommend that applicants minimise controllable process and design differences”, Francer wrote.
Several big biopharma companies reference the PhRMA comments in their own feedback to the FDA. Novo Nordisk and BIO (Biotechnology Industry Organization) have also expressed concerns.
Know your limits
Assessments of biosimilarity rely on analytical characterisation. However, Francer writes, these tools have limitations and a “thorough understanding” of these the weaknesses is needed to identify uncertainties which need checking in preclinical or clinical studies.
“Because the statutory standard for biosimilarity rests in the negative - in establishing the absence of clinically meaningful differences - recognising an analytical programme’s limitations is equally important as, if not more important than, recognising its strengths”, Francer wrote.