Manufacturers developing biosimilars in Europe want regulators to go back to comparing their therapies with the reference product, based on the actual amount of active ingredient in a dose, rather than a proposed standard that compares dosages and routes of administration.

When posology [i.e. the nominal dosage] is used as the standard of strength rather than the actual measure of the active ingredient, biosimilar developers may believe they are formulating their product to the true label strength, when in fact the reference product’s dosage strength may be in error, say companies commenting on an October draft guideline from the European Medicines Agency.

The concern stems from a provision in the guideline that says posology and route of administration must be the same between reference and biosimilar. Under the previous guideline, companies were required to assess similarity based on the measured amount of the active ingredient.

It is not sufficient to specify that the products should have the same posology, says Amgen. That sentiment was mirrored by trade group EuropaBio.  

In addition, commenters warn of the guideline’s continued use of the word “comparability,” which Boehringer Ingelheim and European Biopharmaceutical Enterprises believe could sew confusion by conflating the term with biosimilarity. The EMA should make clear that comparability is only in reference to manufacturing process changes between batches of the same product, rather than between the biosimilar and its reference, they say. 

Several of the 24 commenters also caution against confusing biosimilars with generic drugs. EuropaBio and Pfizer worry that the EMA has done just that with several recent products by labeling the biosimilars as if they were generic versions of the reference therapy.

In a separate announcement, the European Generics Associations’ biosimilars group said Wednesday that it strongly supports the EMA’s position on biosimilar labeling, which requires the biosimilar product’s label to be consistent with that of the reference product.

Labeling has proven a major point of contention in the U.S., where firms are awaiting how the FDA will decide on the matter. GPhA warns that requiring different labels for biosimilars would slow market acceptance of the therapies, while several brand companies argue patients and prescribers should be notified of the difference between reference and biosimilars.

The [EMA’s] October guideline focuses in large part on allowing biosimilar applicants in the EU to employ comparator data from biologics approved outside the bloc. — Bryan Koenig

Originally appeared in Drug Industry Daily, the pharmaceutical industry’s number one source for regulatory news and information. Click here for more information.