Legislative initiatives in Europe, Canada and the US for market authorization of follow-on biologics.

The formulation and application of legal and regulatory requirements for the market authorization of follow-on versions of biological drugs present challenges. This review discusses relevant regulatory guidelines and legislative initiatives related to market authorization for follow-on biologics in Europe, Canada and the US. The respective positions of these three markets is analyzed with regard to several factors: criteria for the choice of reference products; requirements for the comparability exercise between a candidate follow-on biologic and the selected reference product, with an emphasis on considerations of quality, safety and efficacy data; the interchangeability of a reference product with related follow-on drugs; data exclusivity provisions; and the application of specialized patent enforcement mechanisms to follow-on biologics.