The European Commission has finally published the draft amendment to Regulation No 847/2000 regarding the concept of “similar medicinal product” for the purposes of the Orphan Medicinal Products Regulation. A key incentive of this Regulation is the ten-year market exclusivity that protects an orphan medicinal product, whereby national competent authorities shall not accept an application for authorisation, or grant an authorisation, or accept an application to extend an existing authorisation, “for the same therapeutic indication, in respect of a similar medicinal product” as the orphan product. Regulation 847/2000 defines “similar medicinal product” in this context, and sets out a number of examples of what kind of products will be similar.

Following a consultation last year, the Commission intends to make changes to the 17-year-old text to account for the rise of cell therapies and other advanced therapy medicinal products, the nature of which do not fit neatly into the current definitions.

Advanced Therapy Medicinal Products

Under the current rules, Regulation 847/2000 defines a “similar medicinal product” as “a medicinal product containing a similar active substance or substances …, and which is intended for the same therapeutic indication”. However, the detail of what this means in practice is set out in the definition of “similar active substance”, which means “an identical active substance, or an active substance with the same principal molecular structural features … and which acts via the same mechanism”. However, researchers cannot fully identify the principal molecular structural features of advanced therapy medicinal products, such as cell-based and gene therapies, which makes using this definition difficult for these products.

To address this, the Commission wants to expand the definition of similar active substance to allow similarity to be assessed “on the basis of the biological and functional characteristics” if the principal molecular structural features are unknown or cannot be fully established. The definition will therefore be updated so the criteria for similarity will depend on whether the products are chemical, biological, advanced therapy or radiopharmaceutical medicinal products. The examples will also be updated to take into account technological progress.

Comments on the proposal are due by 27 November 2017.